update from upstream

11 files changed, 1624 insertions, 308 deletions

diff --git a/hypervideo_dl/postprocessor/__init__.py b/hypervideo_dl/postprocessor/__init__.py
index 3ea5183..07c87b7 100644
--- a/hypervideo_dl/postprocessor/__init__.py
+++ b/hypervideo_dl/postprocessor/__init__.py
@@ -1,40 +1,43 @@
-from __future__ import unicode_literals
+# flake8: noqa: F401
+
+from ..utils import load_plugins
 
 from .embedthumbnail import EmbedThumbnailPP
+from .exec import ExecPP, ExecAfterDownloadPP
 from .ffmpeg import (
     FFmpegPostProcessor,
     FFmpegEmbedSubtitlePP,
     FFmpegExtractAudioPP,
+    FFmpegFixupDurationPP,
     FFmpegFixupStretchedPP,
+    FFmpegFixupTimestampPP,
     FFmpegFixupM3u8PP,
     FFmpegFixupM4aPP,
     FFmpegMergerPP,
     FFmpegMetadataPP,
-    FFmpegVideoConvertorPP,
     FFmpegSubtitlesConvertorPP,
+    FFmpegThumbnailsConvertorPP,
+    FFmpegSplitChaptersPP,
+    FFmpegVideoConvertorPP,
+    FFmpegVideoRemuxerPP,
 )
+from .metadataparser import (
+    MetadataFromFieldPP,
+    MetadataFromTitlePP,
+    MetadataParserPP,
+)
+from .modify_chapters import ModifyChaptersPP
+from .movefilesafterdownload import MoveFilesAfterDownloadPP
+from .sponskrub import SponSkrubPP
+from .sponsorblock import SponsorBlockPP
 from .xattrpp import XAttrMetadataPP
-from .execafterdownload import ExecAfterDownloadPP
-from .metadatafromtitle import MetadataFromTitlePP
+
+_PLUGIN_CLASSES = load_plugins('postprocessor', 'PP', globals())
 
 
 def get_postprocessor(key):
     return globals()[key + 'PP']
 
 
-__all__ = [
-    'EmbedThumbnailPP',
-    'ExecAfterDownloadPP',
-    'FFmpegEmbedSubtitlePP',
-    'FFmpegExtractAudioPP',
-    'FFmpegFixupM3u8PP',
-    'FFmpegFixupM4aPP',
-    'FFmpegFixupStretchedPP',
-    'FFmpegMergerPP',
-    'FFmpegMetadataPP',
-    'FFmpegPostProcessor',
-    'FFmpegSubtitlesConvertorPP',
-    'FFmpegVideoConvertorPP',
-    'MetadataFromTitlePP',
-    'XAttrMetadataPP',
-]
+__all__ = [name for name in globals().keys() if name.endswith('IE')]
+__all__.append('FFmpegPostProcessor')
diff --git a/hypervideo_dl/postprocessor/common.py b/hypervideo_dl/postprocessor/common.py
index 599dd1d..b491afb 100644
--- a/hypervideo_dl/postprocessor/common.py
+++ b/hypervideo_dl/postprocessor/common.py
@@ -1,15 +1,38 @@
 from __future__ import unicode_literals
 
+import copy
+import functools
 import os
 
+from ..compat import compat_str
 from ..utils import (
-    PostProcessingError,
-    cli_configuration_args,
+    _configuration_args,
     encodeFilename,
+    PostProcessingError,
 )
 
 
-class PostProcessor(object):
+class PostProcessorMetaClass(type):
+    @staticmethod
+    def run_wrapper(func):
+        @functools.wraps(func)
+        def run(self, info, *args, **kwargs):
+            info_copy = copy.deepcopy(self._copy_infodict(info))
+            self._hook_progress({'status': 'started'}, info_copy)
+            ret = func(self, info, *args, **kwargs)
+            if ret is not None:
+                _, info = ret
+            self._hook_progress({'status': 'finished'}, info_copy)
+            return ret
+        return run
+
+    def __new__(cls, name, bases, attrs):
+        if 'run' in attrs:
+            attrs['run'] = cls.run_wrapper(attrs['run'])
+        return type.__new__(cls, name, bases, attrs)
+
+
+class PostProcessor(metaclass=PostProcessorMetaClass):
     """Post Processor class.
 
     PostProcessor objects can be added to downloaders with their
@@ -32,11 +55,66 @@ class PostProcessor(object):
     _downloader = None
 
     def __init__(self, downloader=None):
-        self._downloader = downloader
+        self._progress_hooks = []
+        self.add_progress_hook(self.report_progress)
+        self.set_downloader(downloader)
+        self.PP_NAME = self.pp_key()
+
+    @classmethod
+    def pp_key(cls):
+        name = cls.__name__[:-2]
+        return compat_str(name[6:]) if name[:6].lower() == 'ffmpeg' else name
+
+    def to_screen(self, text, prefix=True, *args, **kwargs):
+        tag = '[%s] ' % self.PP_NAME if prefix else ''
+        if self._downloader:
+            return self._downloader.to_screen('%s%s' % (tag, text), *args, **kwargs)
+
+    def report_warning(self, text, *args, **kwargs):
+        if self._downloader:
+            return self._downloader.report_warning(text, *args, **kwargs)
+
+    def report_error(self, text, *args, **kwargs):
+        # Exists only for compatibility. Do not use
+        if self._downloader:
+            return self._downloader.report_error(text, *args, **kwargs)
+
+    def write_debug(self, text, *args, **kwargs):
+        if self._downloader:
+            return self._downloader.write_debug(text, *args, **kwargs)
+
+    def get_param(self, name, default=None, *args, **kwargs):
+        if self._downloader:
+            return self._downloader.params.get(name, default, *args, **kwargs)
+        return default
 
     def set_downloader(self, downloader):
         """Sets the downloader for this PP."""
         self._downloader = downloader
+        for ph in getattr(downloader, '_postprocessor_hooks', []):
+            self.add_progress_hook(ph)
+
+    def _copy_infodict(self, info_dict):
+        return getattr(self._downloader, '_copy_infodict', dict)(info_dict)
+
+    @staticmethod
+    def _restrict_to(*, video=True, audio=True, images=True):
+        allowed = {'video': video, 'audio': audio, 'images': images}
+
+        def decorator(func):
+            @functools.wraps(func)
+            def wrapper(self, info):
+                format_type = (
+                    'video' if info.get('vcodec') != 'none'
+                    else 'audio' if info.get('acodec') != 'none'
+                    else 'images')
+                if allowed[format_type]:
+                    return func(self, info)
+                else:
+                    self.to_screen('Skipping %s' % format_type)
+                    return [], info
+            return wrapper
+        return decorator
 
     def run(self, information):
         """Run the PostProcessor.
@@ -59,10 +137,41 @@ class PostProcessor(object):
         try:
             os.utime(encodeFilename(path), (atime, mtime))
         except Exception:
-            self._downloader.report_warning(errnote)
-
-    def _configuration_args(self, default=[]):
-        return cli_configuration_args(self._downloader.params, 'postprocessor_args', default)
+            self.report_warning(errnote)
+
+    def _configuration_args(self, exe, *args, **kwargs):
+        return _configuration_args(
+            self.pp_key(), self.get_param('postprocessor_args'), exe, *args, **kwargs)
+
+    def _hook_progress(self, status, info_dict):
+        if not self._progress_hooks:
+            return
+        status.update({
+            'info_dict': info_dict,
+            'postprocessor': self.pp_key(),
+        })
+        for ph in self._progress_hooks:
+            ph(status)
+
+    def add_progress_hook(self, ph):
+        # See YoutubeDl.py (search for postprocessor_hooks) for a description of this interface
+        self._progress_hooks.append(ph)
+
+    def report_progress(self, s):
+        s['_default_template'] = '%(postprocessor)s %(status)s' % s
+
+        progress_dict = s.copy()
+        progress_dict.pop('info_dict')
+        progress_dict = {'info': s['info_dict'], 'progress': progress_dict}
+
+        progress_template = self.get_param('progress_template', {})
+        tmpl = progress_template.get('postprocess')
+        if tmpl:
+            self._downloader.to_stdout(self._downloader.evaluate_outtmpl(tmpl, progress_dict))
+
+        self._downloader.to_console_title(self._downloader.evaluate_outtmpl(
+            progress_template.get('postprocess-title') or 'hypervideo %(progress._default_template)s',
+            progress_dict))
 
 
 class AudioConversionError(PostProcessingError):
diff --git a/hypervideo_dl/postprocessor/embedthumbnail.py b/hypervideo_dl/postprocessor/embedthumbnail.py
index 3990908..3139a63 100644
--- a/hypervideo_dl/postprocessor/embedthumbnail.py
+++ b/hypervideo_dl/postprocessor/embedthumbnail.py
@@ -1,20 +1,35 @@
 # coding: utf-8
 from __future__ import unicode_literals
 
-
+import base64
+import imghdr
 import os
 import subprocess
-
-from .ffmpeg import FFmpegPostProcessor
-
+import re
+
+try:
+    from mutagen.flac import Picture, FLAC
+    from mutagen.mp4 import MP4, MP4Cover
+    from mutagen.oggopus import OggOpus
+    from mutagen.oggvorbis import OggVorbis
+    has_mutagen = True
+except ImportError:
+    has_mutagen = False
+
+from .common import PostProcessor
+from .ffmpeg import (
+    FFmpegPostProcessor,
+    FFmpegThumbnailsConvertorPP,
+)
 from ..utils import (
     check_executable,
     encodeArgument,
     encodeFilename,
+    error_to_compat_str,
     PostProcessingError,
     prepend_extension,
-    replace_extension,
-    shell_quote
+    process_communicate_or_kill,
+    shell_quote,
 )
 
 
@@ -23,108 +38,198 @@ class EmbedThumbnailPPError(PostProcessingError):
 
 
 class EmbedThumbnailPP(FFmpegPostProcessor):
+
     def __init__(self, downloader=None, already_have_thumbnail=False):
-        super(EmbedThumbnailPP, self).__init__(downloader)
+        FFmpegPostProcessor.__init__(self, downloader)
         self._already_have_thumbnail = already_have_thumbnail
 
+    def _get_thumbnail_resolution(self, filename, thumbnail_dict):
+        def guess():
+            width, height = thumbnail_dict.get('width'), thumbnail_dict.get('height')
+            if width and height:
+                return width, height
+
+        try:
+            size_regex = r',\s*(?P<w>\d+)x(?P<h>\d+)\s*[,\[]'
+            size_result = self.run_ffmpeg(filename, None, ['-hide_banner'], expected_retcodes=(1,))
+            mobj = re.search(size_regex, size_result)
+            if mobj is None:
+                return guess()
+        except PostProcessingError as err:
+            self.report_warning('unable to find the thumbnail resolution; %s' % error_to_compat_str(err))
+            return guess()
+        return int(mobj.group('w')), int(mobj.group('h'))
+
+    def _report_run(self, exe, filename):
+        self.to_screen('%s: Adding thumbnail to "%s"' % (exe, filename))
+
+    @PostProcessor._restrict_to(images=False)
     def run(self, info):
         filename = info['filepath']
         temp_filename = prepend_extension(filename, 'temp')
 
         if not info.get('thumbnails'):
-            self._downloader.to_screen('[embedthumbnail] There aren\'t any thumbnails to embed')
+            self.to_screen('There aren\'t any thumbnails to embed')
             return [], info
 
-        thumbnail_filename = info['thumbnails'][-1]['filename']
-
+        idx = next((-i for i, t in enumerate(info['thumbnails'][::-1], 1) if t.get('filepath')), None)
+        if idx is None:
+            self.to_screen('There are no thumbnails on disk')
+            return [], info
+        thumbnail_filename = info['thumbnails'][idx]['filepath']
         if not os.path.exists(encodeFilename(thumbnail_filename)):
-            self._downloader.report_warning(
-                'Skipping embedding the thumbnail because the file is missing.')
+            self.report_warning('Skipping embedding the thumbnail because the file is missing.')
             return [], info
 
-        def is_webp(path):
-            with open(encodeFilename(path), 'rb') as f:
-                b = f.read(12)
-            return b[0:4] == b'RIFF' and b[8:] == b'WEBP'
-
         # Correct extension for WebP file with wrong extension (see #25687, #25717)
-        _, thumbnail_ext = os.path.splitext(thumbnail_filename)
-        if thumbnail_ext:
-            thumbnail_ext = thumbnail_ext[1:].lower()
-            if thumbnail_ext != 'webp' and is_webp(thumbnail_filename):
-                self._downloader.to_screen(
-                    '[ffmpeg] Correcting extension to webp and escaping path for thumbnail "%s"' % thumbnail_filename)
-                thumbnail_webp_filename = replace_extension(thumbnail_filename, 'webp')
-                os.rename(encodeFilename(thumbnail_filename), encodeFilename(thumbnail_webp_filename))
-                thumbnail_filename = thumbnail_webp_filename
-                thumbnail_ext = 'webp'
-
-        # Convert unsupported thumbnail formats to JPEG (see #25687, #25717)
-        if thumbnail_ext not in ['jpg', 'png']:
-            # NB: % is supposed to be escaped with %% but this does not work
-            # for input files so working around with standard substitution
-            escaped_thumbnail_filename = thumbnail_filename.replace('%', '#')
-            os.rename(encodeFilename(thumbnail_filename), encodeFilename(escaped_thumbnail_filename))
-            escaped_thumbnail_jpg_filename = replace_extension(escaped_thumbnail_filename, 'jpg')
-            self._downloader.to_screen('[ffmpeg] Converting thumbnail "%s" to JPEG' % escaped_thumbnail_filename)
-            self.run_ffmpeg(escaped_thumbnail_filename, escaped_thumbnail_jpg_filename, ['-bsf:v', 'mjpeg2jpeg'])
-            os.remove(encodeFilename(escaped_thumbnail_filename))
-            thumbnail_jpg_filename = replace_extension(thumbnail_filename, 'jpg')
-            # Rename back to unescaped for further processing
-            os.rename(encodeFilename(escaped_thumbnail_jpg_filename), encodeFilename(thumbnail_jpg_filename))
-            thumbnail_filename = thumbnail_jpg_filename
-
-        if info['ext'] == 'mp3':
-            options = [
-                '-c', 'copy', '-map', '0', '-map', '1',
-                '-metadata:s:v', 'title="Album cover"', '-metadata:s:v', 'comment="Cover (Front)"']
+        convertor = FFmpegThumbnailsConvertorPP(self._downloader)
+        convertor.fixup_webp(info, idx)
 
-            self._downloader.to_screen('[ffmpeg] Adding thumbnail to "%s"' % filename)
+        original_thumbnail = thumbnail_filename = info['thumbnails'][idx]['filepath']
 
-            self.run_ffmpeg_multiple_files([filename, thumbnail_filename], temp_filename, options)
-
-            if not self._already_have_thumbnail:
-                os.remove(encodeFilename(thumbnail_filename))
-            os.remove(encodeFilename(filename))
-            os.rename(encodeFilename(temp_filename), encodeFilename(filename))
-
-        elif info['ext'] in ['m4a', 'mp4']:
-            atomicparsley = next((x
-                                  for x in ['AtomicParsley', 'atomicparsley']
-                                  if check_executable(x, ['-v'])), None)
+        # Convert unsupported thumbnail formats to PNG (see #25687, #25717)
+        # Original behavior was to convert to JPG, but since JPG is a lossy
+        # format, there will be some additional data loss.
+        # PNG, on the other hand, is lossless.
+        thumbnail_ext = os.path.splitext(thumbnail_filename)[1][1:]
+        if thumbnail_ext not in ('jpg', 'jpeg', 'png'):
+            thumbnail_filename = convertor.convert_thumbnail(thumbnail_filename, 'png')
+            thumbnail_ext = 'png'
 
-            if atomicparsley is None:
-                raise EmbedThumbnailPPError('AtomicParsley was not found. Please install.')
+        mtime = os.stat(encodeFilename(filename)).st_mtime
 
-            cmd = [encodeFilename(atomicparsley, True),
-                   encodeFilename(filename, True),
-                   encodeArgument('--artwork'),
-                   encodeFilename(thumbnail_filename, True),
-                   encodeArgument('-o'),
-                   encodeFilename(temp_filename, True)]
+        success = True
+        if info['ext'] == 'mp3':
+            options = [
+                '-c', 'copy', '-map', '0:0', '-map', '1:0', '-id3v2_version', '3',
+                '-metadata:s:v', 'title="Album cover"', '-metadata:s:v', 'comment="Cover (front)"']
 
-            self._downloader.to_screen('[atomicparsley] Adding thumbnail to "%s"' % filename)
+            self._report_run('ffmpeg', filename)
+            self.run_ffmpeg_multiple_files([filename, thumbnail_filename], temp_filename, options)
 
-            if self._downloader.params.get('verbose', False):
-                self._downloader.to_screen('[debug] AtomicParsley command line: %s' % shell_quote(cmd))
+        elif info['ext'] in ['mkv', 'mka']:
+            options = ['-c', 'copy', '-map', '0', '-dn']
+
+            mimetype = 'image/%s' % ('png' if thumbnail_ext == 'png' else 'jpeg')
+            old_stream, new_stream = self.get_stream_number(
+                filename, ('tags', 'mimetype'), mimetype)
+            if old_stream is not None:
+                options.extend(['-map', '-0:%d' % old_stream])
+                new_stream -= 1
+            options.extend([
+                '-attach', thumbnail_filename,
+                '-metadata:s:%d' % new_stream, 'mimetype=%s' % mimetype,
+                '-metadata:s:%d' % new_stream, 'filename=cover.%s' % thumbnail_ext])
+
+            self._report_run('ffmpeg', filename)
+            self.run_ffmpeg(filename, temp_filename, options)
+
+        elif info['ext'] in ['m4a', 'mp4', 'mov']:
+            prefer_atomicparsley = 'embed-thumbnail-atomicparsley' in self.get_param('compat_opts', [])
+            # Method 1: Use mutagen
+            if not has_mutagen or prefer_atomicparsley:
+                success = False
+            else:
+                try:
+                    self._report_run('mutagen', filename)
+                    meta = MP4(filename)
+                    # NOTE: the 'covr' atom is a non-standard MPEG-4 atom,
+                    # Apple iTunes 'M4A' files include the 'moov.udta.meta.ilst' atom.
+                    f = {'jpeg': MP4Cover.FORMAT_JPEG, 'png': MP4Cover.FORMAT_PNG}[imghdr.what(thumbnail_filename)]
+                    with open(thumbnail_filename, 'rb') as thumbfile:
+                        thumb_data = thumbfile.read()
+                    meta.tags['covr'] = [MP4Cover(data=thumb_data, imageformat=f)]
+                    meta.save()
+                    temp_filename = filename
+                except Exception as err:
+                    self.report_warning('unable to embed using mutagen; %s' % error_to_compat_str(err))
+                    success = False
+
+            # Method 2: Use ffmpeg+ffprobe
+            if not success and not prefer_atomicparsley:
+                success = True
+                try:
+                    options = ['-c', 'copy', '-map', '0', '-dn', '-map', '1']
+
+                    old_stream, new_stream = self.get_stream_number(
+                        filename, ('disposition', 'attached_pic'), 1)
+                    if old_stream is not None:
+                        options.extend(['-map', '-0:%d' % old_stream])
+                        new_stream -= 1
+                    options.extend(['-disposition:%s' % new_stream, 'attached_pic'])
+
+                    self._report_run('ffmpeg', filename)
+                    self.run_ffmpeg_multiple_files([filename, thumbnail_filename], temp_filename, options)
+                except PostProcessingError as err:
+                    self.report_warning('unable to embed using ffprobe & ffmpeg; %s' % error_to_compat_str(err))
+                    success = False
+
+            # Method 3: Use AtomicParsley
+            if not success:
+                success = True
+                atomicparsley = next((
+                    x for x in ['AtomicParsley', 'atomicparsley']
+                    if check_executable(x, ['-v'])), None)
+                if atomicparsley is None:
+                    raise EmbedThumbnailPPError('AtomicParsley was not found. Please install')
+
+                cmd = [encodeFilename(atomicparsley, True),
+                       encodeFilename(filename, True),
+                       encodeArgument('--artwork'),
+                       encodeFilename(thumbnail_filename, True),
+                       encodeArgument('-o'),
+                       encodeFilename(temp_filename, True)]
+                cmd += [encodeArgument(o) for o in self._configuration_args('AtomicParsley')]
+
+                self._report_run('atomicparsley', filename)
+                self.write_debug('AtomicParsley command line: %s' % shell_quote(cmd))
+                p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+                stdout, stderr = process_communicate_or_kill(p)
+                if p.returncode != 0:
+                    msg = stderr.decode('utf-8', 'replace').strip()
+                    raise EmbedThumbnailPPError(msg)
+                # for formats that don't support thumbnails (like 3gp) AtomicParsley
+                # won't create to the temporary file
+                if b'No changes' in stdout:
+                    self.report_warning('The file format doesn\'t support embedding a thumbnail')
+                    success = False
+
+        elif info['ext'] in ['ogg', 'opus', 'flac']:
+            if not has_mutagen:
+                raise EmbedThumbnailPPError('module mutagen was not found. Please install using `python -m pip install mutagen`')
+
+            self._report_run('mutagen', filename)
+            f = {'opus': OggOpus, 'flac': FLAC, 'ogg': OggVorbis}[info['ext']](filename)
+
+            pic = Picture()
+            pic.mime = 'image/%s' % imghdr.what(thumbnail_filename)
+            with open(thumbnail_filename, 'rb') as thumbfile:
+                pic.data = thumbfile.read()
+            pic.type = 3  # front cover
+            res = self._get_thumbnail_resolution(thumbnail_filename, info['thumbnails'][idx])
+            if res is not None:
+                pic.width, pic.height = res
+
+            if info['ext'] == 'flac':
+                f.add_picture(pic)
+            else:
+                # https://wiki.xiph.org/VorbisComment#METADATA_BLOCK_PICTURE
+                f['METADATA_BLOCK_PICTURE'] = base64.b64encode(pic.write()).decode('ascii')
+            f.save()
+            temp_filename = filename
 
-            p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-            stdout, stderr = p.communicate()
+        else:
+            raise EmbedThumbnailPPError('Supported filetypes for thumbnail embedding are: mp3, mkv/mka, ogg/opus/flac, m4a/mp4/mov')
 
-            if p.returncode != 0:
-                msg = stderr.decode('utf-8', 'replace').strip()
-                raise EmbedThumbnailPPError(msg)
+        if success and temp_filename != filename:
+            os.replace(temp_filename, filename)
 
-            if not self._already_have_thumbnail:
-                os.remove(encodeFilename(thumbnail_filename))
-            # for formats that don't support thumbnails (like 3gp) AtomicParsley
-            # won't create to the temporary file
-            if b'No changes' in stdout:
-                self._downloader.report_warning('The file format doesn\'t support embedding a thumbnail')
-            else:
-                os.remove(encodeFilename(filename))
-                os.rename(encodeFilename(temp_filename), encodeFilename(filename))
-        else:
-            raise EmbedThumbnailPPError('Only mp3 and m4a/mp4 are supported for thumbnail embedding for now.')
+        self.try_utime(filename, mtime, mtime)
 
-        return [], info
+        files_to_delete = [thumbnail_filename]
+        if self._already_have_thumbnail:
+            if original_thumbnail == thumbnail_filename:
+                files_to_delete = []
+        elif original_thumbnail != thumbnail_filename:
+            files_to_delete.append(original_thumbnail)
+        return files_to_delete, info
diff --git a/hypervideo_dl/postprocessor/exec.py b/hypervideo_dl/postprocessor/exec.py
new file mode 100644
index 0000000..7a3cb49
--- /dev/null
+++ b/hypervideo_dl/postprocessor/exec.py
@@ -0,0 +1,42 @@
+from __future__ import unicode_literals
+
+import subprocess
+
+from .common import PostProcessor
+from ..compat import compat_shlex_quote
+from ..utils import (
+    encodeArgument,
+    PostProcessingError,
+    variadic,
+)
+
+
+class ExecPP(PostProcessor):
+
+    def __init__(self, downloader, exec_cmd):
+        PostProcessor.__init__(self, downloader)
+        self.exec_cmd = variadic(exec_cmd)
+
+    def parse_cmd(self, cmd, info):
+        tmpl, tmpl_dict = self._downloader.prepare_outtmpl(cmd, info)
+        if tmpl_dict:  # if there are no replacements, tmpl_dict = {}
+            return self._downloader.escape_outtmpl(tmpl) % tmpl_dict
+
+        # If no replacements are found, replace {} for backard compatibility
+        if '{}' not in cmd:
+            cmd += ' {}'
+        return cmd.replace('{}', compat_shlex_quote(
+            info.get('filepath') or info['_filename']))
+
+    def run(self, info):
+        for tmpl in self.exec_cmd:
+            cmd = self.parse_cmd(tmpl, info)
+            self.to_screen('Executing command: %s' % cmd)
+            retCode = subprocess.call(encodeArgument(cmd), shell=True)
+            if retCode != 0:
+                raise PostProcessingError('Command returned error code %d' % retCode)
+        return [], info
+
+
+class ExecAfterDownloadPP(ExecPP):  # for backward compatibility
+    pass
diff --git a/hypervideo_dl/postprocessor/ffmpeg.py b/hypervideo_dl/postprocessor/ffmpeg.py
index 3078329..a6d6d78 100644
--- a/hypervideo_dl/postprocessor/ffmpeg.py
+++ b/hypervideo_dl/postprocessor/ffmpeg.py
@@ -1,26 +1,32 @@
 from __future__ import unicode_literals
 
 import io
+import itertools
 import os
 import subprocess
 import time
 import re
-
+import json
 
 from .common import AudioConversionError, PostProcessor
 
+from ..compat import compat_str
 from ..utils import (
+    dfxp2srt,
     encodeArgument,
     encodeFilename,
+    float_or_none,
     get_exe_version,
     is_outdated_version,
+    ISO639Utils,
+    orderedSet,
     PostProcessingError,
     prepend_extension,
-    shell_quote,
-    subtitles_filename,
-    dfxp2srt,
-    ISO639Utils,
+    process_communicate_or_kill,
     replace_extension,
+    shell_quote,
+    traverse_obj,
+    variadic,
 )
 
 
@@ -58,15 +64,14 @@ class FFmpegPostProcessor(PostProcessor):
 
     def check_version(self):
         if not self.available:
-            raise FFmpegPostProcessorError('ffmpeg or avconv not found. Please install one.')
+            raise FFmpegPostProcessorError('ffmpeg not found. Please install or provide the path using --ffmpeg-location')
 
         required_version = '10-0' if self.basename == 'avconv' else '1.0'
         if is_outdated_version(
                 self._versions[self.basename], required_version):
             warning = 'Your copy of %s is outdated, update %s to version %s or newer if you encounter any errors.' % (
                 self.basename, self.basename, required_version)
-            if self._downloader:
-                self._downloader.report_warning(warning)
+            self.report_warning(warning)
 
     @staticmethod
     def get_versions(downloader=None):
@@ -96,30 +101,28 @@ class FFmpegPostProcessor(PostProcessor):
         self._paths = None
         self._versions = None
         if self._downloader:
-            prefer_ffmpeg = self._downloader.params.get('prefer_ffmpeg', True)
-            location = self._downloader.params.get('ffmpeg_location')
+            prefer_ffmpeg = self.get_param('prefer_ffmpeg', True)
+            location = self.get_param('ffmpeg_location')
             if location is not None:
                 if not os.path.exists(location):
-                    self._downloader.report_warning(
+                    self.report_warning(
                         'ffmpeg-location %s does not exist! '
-                        'Continuing without avconv/ffmpeg.' % (location))
+                        'Continuing without ffmpeg.' % (location))
                     self._versions = {}
                     return
-                elif not os.path.isdir(location):
+                elif os.path.isdir(location):
+                    dirname, basename = location, None
+                else:
                     basename = os.path.splitext(os.path.basename(location))[0]
-                    if basename not in programs:
-                        self._downloader.report_warning(
-                            'Cannot identify executable %s, its basename should be one of %s. '
-                            'Continuing without avconv/ffmpeg.' %
-                            (location, ', '.join(programs)))
-                        self._versions = {}
-                        return None
-                    location = os.path.dirname(os.path.abspath(location))
+                    basename = next((p for p in programs if basename.startswith(p)), 'ffmpeg')
+                    dirname = os.path.dirname(os.path.abspath(location))
                     if basename in ('ffmpeg', 'ffprobe'):
                         prefer_ffmpeg = True
 
                 self._paths = dict(
-                    (p, os.path.join(location, p)) for p in programs)
+                    (p, os.path.join(dirname, p)) for p in programs)
+                if basename:
+                    self._paths[basename] = location
                 self._versions = dict(
                     (p, get_ffmpeg_version(self._paths[p])) for p in programs)
         if self._versions is None:
@@ -163,7 +166,7 @@ class FFmpegPostProcessor(PostProcessor):
 
     def get_audio_codec(self, path):
         if not self.probe_available and not self.available:
-            raise PostProcessingError('ffprobe/avprobe and ffmpeg/avconv not found. Please install one.')
+            raise PostProcessingError('ffprobe and ffmpeg not found. Please install or provide the path using --ffmpeg-location')
         try:
             if self.probe_available:
                 cmd = [
@@ -174,13 +177,11 @@ class FFmpegPostProcessor(PostProcessor):
                     encodeFilename(self.executable, True),
                     encodeArgument('-i')]
             cmd.append(encodeFilename(self._ffmpeg_filename_argument(path), True))
-            if self._downloader.params.get('verbose', False):
-                self._downloader.to_screen(
-                    '[debug] %s command line: %s' % (self.basename, shell_quote(cmd)))
+            self.write_debug('%s command line: %s' % (self.basename, shell_quote(cmd)))
             handle = subprocess.Popen(
                 cmd, stderr=subprocess.PIPE,
                 stdout=subprocess.PIPE, stdin=subprocess.PIPE)
-            stdout_data, stderr_data = handle.communicate()
+            stdout_data, stderr_data = process_communicate_or_kill(handle)
             expected_ret = 0 if self.probe_available else 1
             if handle.wait() != expected_ret:
                 return None
@@ -203,55 +204,174 @@ class FFmpegPostProcessor(PostProcessor):
                 return mobj.group(1)
         return None
 
-    def run_ffmpeg_multiple_files(self, input_paths, out_path, opts):
+    def get_metadata_object(self, path, opts=[]):
+        if self.probe_basename != 'ffprobe':
+            if self.probe_available:
+                self.report_warning('Only ffprobe is supported for metadata extraction')
+            raise PostProcessingError('ffprobe not found. Please install or provide the path using --ffmpeg-location')
         self.check_version()
 
-        oldest_mtime = min(
-            os.stat(encodeFilename(path)).st_mtime for path in input_paths)
+        cmd = [
+            encodeFilename(self.probe_executable, True),
+            encodeArgument('-hide_banner'),
+            encodeArgument('-show_format'),
+            encodeArgument('-show_streams'),
+            encodeArgument('-print_format'),
+            encodeArgument('json'),
+        ]
+
+        cmd += opts
+        cmd.append(encodeFilename(self._ffmpeg_filename_argument(path), True))
+        self.write_debug('ffprobe command line: %s' % shell_quote(cmd))
+        p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, stdin=subprocess.PIPE)
+        stdout, stderr = p.communicate()
+        return json.loads(stdout.decode('utf-8', 'replace'))
+
+    def get_stream_number(self, path, keys, value):
+        streams = self.get_metadata_object(path)['streams']
+        num = next(
+            (i for i, stream in enumerate(streams) if traverse_obj(stream, keys, casesense=False) == value),
+            None)
+        return num, len(streams)
 
-        opts += self._configuration_args()
+    def _get_real_video_duration(self, info, fatal=True):
+        try:
+            if '_real_duration' not in info:
+                info['_real_duration'] = float_or_none(
+                    traverse_obj(self.get_metadata_object(info['filepath']), ('format', 'duration')))
+            if not info['_real_duration']:
+                raise PostProcessingError('ffprobe returned empty duration')
+        except PostProcessingError as e:
+            if fatal:
+                raise PostProcessingError(f'Unable to determine video duration; {e}')
+        return info.setdefault('_real_duration', None)
+
+    def _duration_mismatch(self, d1, d2):
+        if not d1 or not d2:
+            return None
+        return abs(d1 - d2) > 1
+
+    def run_ffmpeg_multiple_files(self, input_paths, out_path, opts, **kwargs):
+        return self.real_run_ffmpeg(
+            [(path, []) for path in input_paths],
+            [(out_path, opts)], **kwargs)
+
+    def real_run_ffmpeg(self, input_path_opts, output_path_opts, *, expected_retcodes=(0,)):
+        self.check_version()
+
+        oldest_mtime = min(
+            os.stat(encodeFilename(path)).st_mtime for path, _ in input_path_opts if path)
 
-        files_cmd = []
-        for path in input_paths:
-            files_cmd.extend([
-                encodeArgument('-i'),
-                encodeFilename(self._ffmpeg_filename_argument(path), True)
-            ])
         cmd = [encodeFilename(self.executable, True), encodeArgument('-y')]
         # avconv does not have repeat option
         if self.basename == 'ffmpeg':
             cmd += [encodeArgument('-loglevel'), encodeArgument('repeat+info')]
-        cmd += (files_cmd
-                + [encodeArgument(o) for o in opts]
-                + [encodeFilename(self._ffmpeg_filename_argument(out_path), True)])
 
-        if self._downloader.params.get('verbose', False):
-            self._downloader.to_screen('[debug] ffmpeg command line: %s' % shell_quote(cmd))
+        def make_args(file, args, name, number):
+            keys = ['_%s%d' % (name, number), '_%s' % name]
+            if name == 'o' and number == 1:
+                keys.append('')
+            args += self._configuration_args(self.basename, keys)
+            if name == 'i':
+                args.append('-i')
+            return (
+                [encodeArgument(arg) for arg in args]
+                + [encodeFilename(self._ffmpeg_filename_argument(file), True)])
+
+        for arg_type, path_opts in (('i', input_path_opts), ('o', output_path_opts)):
+            cmd += itertools.chain.from_iterable(
+                make_args(path, list(opts), arg_type, i + 1)
+                for i, (path, opts) in enumerate(path_opts) if path)
+
+        self.write_debug('ffmpeg command line: %s' % shell_quote(cmd))
         p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, stdin=subprocess.PIPE)
-        stdout, stderr = p.communicate()
-        if p.returncode != 0:
-            stderr = stderr.decode('utf-8', 'replace')
-            msg = stderr.strip().split('\n')[-1]
-            raise FFmpegPostProcessorError(msg)
-        self.try_utime(out_path, oldest_mtime, oldest_mtime)
+        stdout, stderr = process_communicate_or_kill(p)
+        if p.returncode not in variadic(expected_retcodes):
+            stderr = stderr.decode('utf-8', 'replace').strip()
+            self.write_debug(stderr)
+            raise FFmpegPostProcessorError(stderr.split('\n')[-1])
+        for out_path, _ in output_path_opts:
+            if out_path:
+                self.try_utime(out_path, oldest_mtime, oldest_mtime)
+        return stderr.decode('utf-8', 'replace')
+
+    def run_ffmpeg(self, path, out_path, opts, **kwargs):
+        return self.run_ffmpeg_multiple_files([path], out_path, opts, **kwargs)
 
-    def run_ffmpeg(self, path, out_path, opts):
-        self.run_ffmpeg_multiple_files([path], out_path, opts)
-
-    def _ffmpeg_filename_argument(self, fn):
+    @staticmethod
+    def _ffmpeg_filename_argument(fn):
         # Always use 'file:' because the filename may contain ':' (ffmpeg
         # interprets that as a protocol) or can start with '-' (-- is broken in
         # ffmpeg, see https://ffmpeg.org/trac/ffmpeg/ticket/2127 for details)
         # Also leave '-' intact in order not to break streaming to stdout.
+        if fn.startswith(('http://', 'https://')):
+            return fn
         return 'file:' + fn if fn != '-' else fn
 
+    @staticmethod
+    def _quote_for_ffmpeg(string):
+        # See https://ffmpeg.org/ffmpeg-utils.html#toc-Quoting-and-escaping
+        # A sequence of '' produces '\'''\'';
+        # final replace removes the empty '' between \' \'.
+        string = string.replace("'", r"'\''").replace("'''", "'")
+        # Handle potential ' at string boundaries.
+        string = string[1:] if string[0] == "'" else "'" + string
+        return string[:-1] if string[-1] == "'" else string + "'"
+
+    def force_keyframes(self, filename, timestamps):
+        timestamps = orderedSet(timestamps)
+        if timestamps[0] == 0:
+            timestamps = timestamps[1:]
+        keyframe_file = prepend_extension(filename, 'keyframes.temp')
+        self.to_screen(f'Re-encoding "{filename}" with appropriate keyframes')
+        self.run_ffmpeg(filename, keyframe_file, ['-force_key_frames', ','.join(
+            f'{t:.6f}' for t in timestamps)])
+        return keyframe_file
+
+    def concat_files(self, in_files, out_file, concat_opts=None):
+        """
+        Use concat demuxer to concatenate multiple files having identical streams.
+
+        Only inpoint, outpoint, and duration concat options are supported.
+        See https://ffmpeg.org/ffmpeg-formats.html#concat-1 for details
+        """
+        concat_file = f'{out_file}.concat'
+        self.write_debug(f'Writing concat spec to {concat_file}')
+        with open(concat_file, 'wt', encoding='utf-8') as f:
+            f.writelines(self._concat_spec(in_files, concat_opts))
+
+        out_flags = ['-c', 'copy']
+        if out_file.rpartition('.')[-1] in ('mp4', 'mov'):
+            # For some reason, '-c copy' is not enough to copy subtitles
+            out_flags.extend(['-c:s', 'mov_text', '-movflags', '+faststart'])
+
+        try:
+            self.real_run_ffmpeg(
+                [(concat_file, ['-hide_banner', '-nostdin', '-f', 'concat', '-safe', '0'])],
+                [(out_file, out_flags)])
+        finally:
+            os.remove(concat_file)
+
+    @classmethod
+    def _concat_spec(cls, in_files, concat_opts=None):
+        if concat_opts is None:
+            concat_opts = [{}] * len(in_files)
+        yield 'ffconcat version 1.0\n'
+        for file, opts in zip(in_files, concat_opts):
+            yield f'file {cls._quote_for_ffmpeg(cls._ffmpeg_filename_argument(file))}\n'
+            # Iterate explicitly to yield the following directives in order, ignoring the rest.
+            for directive in 'inpoint', 'outpoint', 'duration':
+                if directive in opts:
+                    yield f'{directive} {opts[directive]}\n'
+
 
 class FFmpegExtractAudioPP(FFmpegPostProcessor):
+    COMMON_AUDIO_EXTS = ('wav', 'flac', 'm4a', 'aiff', 'mp3', 'ogg', 'mka', 'opus', 'wma')
+    SUPPORTED_EXTS = ('best', 'aac', 'flac', 'mp3', 'm4a', 'opus', 'vorbis', 'wav')
+
     def __init__(self, downloader=None, preferredcodec=None, preferredquality=None, nopostoverwrites=False):
         FFmpegPostProcessor.__init__(self, downloader)
-        if preferredcodec is None:
-            preferredcodec = 'best'
-        self._preferredcodec = preferredcodec
+        self._preferredcodec = preferredcodec or 'best'
         self._preferredquality = preferredquality
         self._nopostoverwrites = nopostoverwrites
 
@@ -266,8 +386,14 @@ class FFmpegExtractAudioPP(FFmpegPostProcessor):
         except FFmpegPostProcessorError as err:
             raise AudioConversionError(err.msg)
 
+    @PostProcessor._restrict_to(images=False)
     def run(self, information):
         path = information['filepath']
+        orig_ext = information['ext']
+
+        if self._preferredcodec == 'best' and orig_ext in self.COMMON_AUDIO_EXTS:
+            self.to_screen('Skipping audio extraction since the file is already in a common audio format')
+            return [], information
 
         filecodec = self.get_audio_codec(path)
         if filecodec is None:
@@ -328,11 +454,11 @@ class FFmpegExtractAudioPP(FFmpegPostProcessor):
         # If we download foo.mp3 and convert it to... foo.mp3, then don't delete foo.mp3, silly.
         if (new_path == path
                 or (self._nopostoverwrites and os.path.exists(encodeFilename(new_path)))):
-            self._downloader.to_screen('[ffmpeg] Post-process file %s exists, skipping' % new_path)
+            self.to_screen('Post-process file %s exists, skipping' % new_path)
             return [], information
 
         try:
-            self._downloader.to_screen('[ffmpeg] Destination: ' + new_path)
+            self.to_screen('Destination: ' + new_path)
             self.run_ffmpeg(path, new_path, acodec, more_opts)
         except AudioConversionError as e:
             raise PostProcessingError(
@@ -350,54 +476,102 @@ class FFmpegExtractAudioPP(FFmpegPostProcessor):
 
 
 class FFmpegVideoConvertorPP(FFmpegPostProcessor):
+    SUPPORTED_EXTS = ('mp4', 'mkv', 'flv', 'webm', 'mov', 'avi', 'mp3', 'mka', 'm4a', 'ogg', 'opus')
+    FORMAT_RE = re.compile(r'{0}(?:/{0})*$'.format(r'(?:\w+>)?(?:%s)' % '|'.join(SUPPORTED_EXTS)))
+    _ACTION = 'converting'
+
     def __init__(self, downloader=None, preferedformat=None):
         super(FFmpegVideoConvertorPP, self).__init__(downloader)
-        self._preferedformat = preferedformat
+        self._preferedformats = preferedformat.lower().split('/')
 
-    def run(self, information):
-        path = information['filepath']
-        if information['ext'] == self._preferedformat:
-            self._downloader.to_screen('[ffmpeg] Not converting video file %s - already is in target format %s' % (path, self._preferedformat))
-            return [], information
-        options = []
-        if self._preferedformat == 'avi':
-            options.extend(['-c:v', 'libxvid', '-vtag', 'XVID'])
-        prefix, sep, ext = path.rpartition('.')
-        outpath = prefix + sep + self._preferedformat
-        self._downloader.to_screen('[' + 'ffmpeg' + '] Converting video from %s to %s, Destination: ' % (information['ext'], self._preferedformat) + outpath)
-        self.run_ffmpeg(path, outpath, options)
-        information['filepath'] = outpath
-        information['format'] = self._preferedformat
-        information['ext'] = self._preferedformat
-        return [path], information
+    def _target_ext(self, source_ext):
+        for pair in self._preferedformats:
+            kv = pair.split('>')
+            if len(kv) == 1 or kv[0].strip() == source_ext:
+                return kv[-1].strip()
+
+    @staticmethod
+    def _options(target_ext):
+        if target_ext == 'avi':
+            return ['-c:v', 'libxvid', '-vtag', 'XVID']
+        return []
+
+    @PostProcessor._restrict_to(images=False)
+    def run(self, info):
+        filename, source_ext = info['filepath'], info['ext'].lower()
+        target_ext = self._target_ext(source_ext)
+        _skip_msg = (
+            f'could not find a mapping for {source_ext}' if not target_ext
+            else f'already is in target format {source_ext}' if source_ext == target_ext
+            else None)
+        if _skip_msg:
+            self.to_screen(f'Not {self._ACTION} media file {filename!r}; {_skip_msg}')
+            return [], info
+
+        outpath = replace_extension(filename, target_ext, source_ext)
+        self.to_screen(f'{self._ACTION.title()} video from {source_ext} to {target_ext}; Destination: {outpath}')
+        self.run_ffmpeg(filename, outpath, self._options(target_ext))
+
+        info['filepath'] = outpath
+        info['format'] = info['ext'] = target_ext
+        return [filename], info
+
+
+class FFmpegVideoRemuxerPP(FFmpegVideoConvertorPP):
+    _ACTION = 'remuxing'
+
+    @staticmethod
+    def _options(target_ext):
+        options = ['-c', 'copy', '-map', '0', '-dn']
+        if target_ext in ['mp4', 'm4a', 'mov']:
+            options.extend(['-movflags', '+faststart'])
+        return options
 
 
 class FFmpegEmbedSubtitlePP(FFmpegPostProcessor):
+    def __init__(self, downloader=None, already_have_subtitle=False):
+        super(FFmpegEmbedSubtitlePP, self).__init__(downloader)
+        self._already_have_subtitle = already_have_subtitle
+
+    @PostProcessor._restrict_to(images=False)
     def run(self, information):
         if information['ext'] not in ('mp4', 'webm', 'mkv'):
-            self._downloader.to_screen('[ffmpeg] Subtitles can only be embedded in mp4, webm or mkv files')
+            self.to_screen('Subtitles can only be embedded in mp4, webm or mkv files')
             return [], information
         subtitles = information.get('requested_subtitles')
         if not subtitles:
-            self._downloader.to_screen('[ffmpeg] There aren\'t any subtitles to embed')
+            self.to_screen('There aren\'t any subtitles to embed')
             return [], information
 
         filename = information['filepath']
+        if information.get('duration') and self._duration_mismatch(
+                self._get_real_video_duration(information, False), information['duration']):
+            self.to_screen(f'Skipping {self.pp_key()} since the real and expected durations mismatch')
+            return [], information
 
         ext = information['ext']
-        sub_langs = []
-        sub_filenames = []
+        sub_langs, sub_names, sub_filenames = [], [], []
         webm_vtt_warn = False
+        mp4_ass_warn = False
 
         for lang, sub_info in subtitles.items():
+            if not os.path.exists(sub_info.get('filepath', '')):
+                self.report_warning(f'Skipping embedding {lang} subtitle because the file is missing')
+                continue
             sub_ext = sub_info['ext']
-            if ext != 'webm' or ext == 'webm' and sub_ext == 'vtt':
+            if sub_ext == 'json':
+                self.report_warning('JSON subtitles cannot be embedded')
+            elif ext != 'webm' or ext == 'webm' and sub_ext == 'vtt':
                 sub_langs.append(lang)
-                sub_filenames.append(subtitles_filename(filename, lang, sub_ext, ext))
+                sub_names.append(sub_info.get('name'))
+                sub_filenames.append(sub_info['filepath'])
             else:
                 if not webm_vtt_warn and ext == 'webm' and sub_ext != 'vtt':
                     webm_vtt_warn = True
-                    self._downloader.to_screen('[ffmpeg] Only WebVTT subtitles can be embedded in webm files')
+                    self.report_warning('Only WebVTT subtitles can be embedded in webm files')
+            if not mp4_ass_warn and ext == 'mp4' and sub_ext == 'ass':
+                mp4_ass_warn = True
+                self.report_warning('ASS subtitles cannot be properly embedded in mp4 files; expect issues')
 
         if not sub_langs:
             return [], information
@@ -405,8 +579,7 @@ class FFmpegEmbedSubtitlePP(FFmpegPostProcessor):
         input_files = [filename] + sub_filenames
 
         opts = [
-            '-map', '0',
-            '-c', 'copy',
+            '-c', 'copy', '-map', '0', '-dn',
             # Don't copy the existing subtitles, we may be running the
             # postprocessor a second time
             '-map', '-0:s',
@@ -416,48 +589,100 @@ class FFmpegEmbedSubtitlePP(FFmpegPostProcessor):
         ]
         if information['ext'] == 'mp4':
             opts += ['-c:s', 'mov_text']
-        for (i, lang) in enumerate(sub_langs):
+        for i, (lang, name) in enumerate(zip(sub_langs, sub_names)):
             opts.extend(['-map', '%d:0' % (i + 1)])
             lang_code = ISO639Utils.short2long(lang) or lang
             opts.extend(['-metadata:s:s:%d' % i, 'language=%s' % lang_code])
+            if name:
+                opts.extend(['-metadata:s:s:%d' % i, 'handler_name=%s' % name,
+                             '-metadata:s:s:%d' % i, 'title=%s' % name])
 
         temp_filename = prepend_extension(filename, 'temp')
-        self._downloader.to_screen('[ffmpeg] Embedding subtitles in \'%s\'' % filename)
+        self.to_screen('Embedding subtitles in "%s"' % filename)
         self.run_ffmpeg_multiple_files(input_files, temp_filename, opts)
-        os.remove(encodeFilename(filename))
-        os.rename(encodeFilename(temp_filename), encodeFilename(filename))
+        os.replace(temp_filename, filename)
 
-        return sub_filenames, information
+        files_to_delete = [] if self._already_have_subtitle else sub_filenames
+        return files_to_delete, information
 
 
 class FFmpegMetadataPP(FFmpegPostProcessor):
+
+    def __init__(self, downloader, add_metadata=True, add_chapters=True):
+        FFmpegPostProcessor.__init__(self, downloader)
+        self._add_metadata = add_metadata
+        self._add_chapters = add_chapters
+
+    @staticmethod
+    def _options(target_ext):
+        yield from ('-map', '0', '-dn')
+        if target_ext == 'm4a':
+            yield from ('-vn', '-acodec', 'copy')
+        else:
+            yield from ('-c', 'copy')
+
+    @PostProcessor._restrict_to(images=False)
     def run(self, info):
+        filename, metadata_filename = info['filepath'], None
+        options = []
+        if self._add_chapters and info.get('chapters'):
+            metadata_filename = replace_extension(filename, 'meta')
+            options.extend(self._get_chapter_opts(info['chapters'], metadata_filename))
+        if self._add_metadata:
+            options.extend(self._get_metadata_opts(info))
+
+        if not options:
+            self.to_screen('There isn\'t any metadata to add')
+            return [], info
+
+        temp_filename = prepend_extension(filename, 'temp')
+        self.to_screen('Adding metadata to "%s"' % filename)
+        self.run_ffmpeg_multiple_files(
+            (filename, metadata_filename), temp_filename,
+            itertools.chain(self._options(info['ext']), *options))
+        if metadata_filename:
+            os.remove(metadata_filename)
+        os.replace(temp_filename, filename)
+        return [], info
+
+    @staticmethod
+    def _get_chapter_opts(chapters, metadata_filename):
+        with io.open(metadata_filename, 'wt', encoding='utf-8') as f:
+            def ffmpeg_escape(text):
+                return re.sub(r'([\\=;#\n])', r'\\\1', text)
+
+            metadata_file_content = ';FFMETADATA1\n'
+            for chapter in chapters:
+                metadata_file_content += '[CHAPTER]\nTIMEBASE=1/1000\n'
+                metadata_file_content += 'START=%d\n' % (chapter['start_time'] * 1000)
+                metadata_file_content += 'END=%d\n' % (chapter['end_time'] * 1000)
+                chapter_title = chapter.get('title')
+                if chapter_title:
+                    metadata_file_content += 'title=%s\n' % ffmpeg_escape(chapter_title)
+            f.write(metadata_file_content)
+        yield ('-map_metadata', '1')
+
+    def _get_metadata_opts(self, info):
         metadata = {}
+        meta_prefix = 'meta_'
 
         def add(meta_list, info_list=None):
-            if not info_list:
-                info_list = meta_list
-            if not isinstance(meta_list, (list, tuple)):
-                meta_list = (meta_list,)
-            if not isinstance(info_list, (list, tuple)):
-                info_list = (info_list,)
-            for info_f in info_list:
-                if info.get(info_f) is not None:
-                    for meta_f in meta_list:
-                        metadata[meta_f] = info[info_f]
-                    break
+            value = next((
+                str(info[key]) for key in [meta_prefix] + list(variadic(info_list or meta_list))
+                if info.get(key) is not None), None)
+            if value not in ('', None):
+                metadata.update({meta_f: value for meta_f in variadic(meta_list)})
 
         # See [1-4] for some info on media metadata/metadata supported
         # by ffmpeg.
         # 1. https://kdenlive.org/en/project/adding-meta-data-to-mp4-video/
         # 2. https://wiki.multimedia.cx/index.php/FFmpeg_Metadata
         # 3. https://kodi.wiki/view/Video_file_tagging
-        # 4. http://atomicparsley.sourceforge.net/mpeg-4files.html
 
         add('title', ('track', 'title'))
         add('date', 'upload_date')
-        add(('description', 'comment'), 'description')
-        add('purl', 'webpage_url')
+        add(('description', 'synopsis'), 'description')
+        add(('purl', 'comment'), 'webpage_url')
         add('track', 'track_number')
         add('artist', ('artist', 'creator', 'uploader', 'uploader_id'))
         add('genre')
@@ -469,57 +694,50 @@ class FFmpegMetadataPP(FFmpegPostProcessor):
         add('episode_id', ('episode', 'episode_id'))
         add('episode_sort', 'episode_number')
 
-        if not metadata:
-            self._downloader.to_screen('[ffmpeg] There isn\'t any metadata to add')
-            return [], info
+        for key, value in info.items():
+            if value is not None and key != meta_prefix and key.startswith(meta_prefix):
+                metadata[key[len(meta_prefix):]] = value
 
-        filename = info['filepath']
-        temp_filename = prepend_extension(filename, 'temp')
-        in_filenames = [filename]
-        options = []
+        for name, value in metadata.items():
+            yield ('-metadata', f'{name}={value}')
 
-        if info['ext'] == 'm4a':
-            options.extend(['-vn', '-acodec', 'copy'])
-        else:
-            options.extend(['-c', 'copy'])
+        stream_idx = 0
+        for fmt in info.get('requested_formats') or []:
+            stream_count = 2 if 'none' not in (fmt.get('vcodec'), fmt.get('acodec')) else 1
+            if fmt.get('language'):
+                lang = ISO639Utils.short2long(fmt['language']) or fmt['language']
+                for i in range(stream_count):
+                    yield ('-metadata:s:%d' % (stream_idx + i), 'language=%s' % lang)
+            stream_idx += stream_count
 
-        for (name, value) in metadata.items():
-            options.extend(['-metadata', '%s=%s' % (name, value)])
+        if ('no-attach-info-json' not in self.get_param('compat_opts', [])
+                and '__infojson_filename' in info and info['ext'] in ('mkv', 'mka')):
+            old_stream, new_stream = self.get_stream_number(info['filepath'], ('tags', 'mimetype'), 'application/json')
+            if old_stream is not None:
+                yield ('-map', '-0:%d' % old_stream)
+                new_stream -= 1
 
-        chapters = info.get('chapters', [])
-        if chapters:
-            metadata_filename = replace_extension(filename, 'meta')
-            with io.open(metadata_filename, 'wt', encoding='utf-8') as f:
-                def ffmpeg_escape(text):
-                    return re.sub(r'(=|;|#|\\|\n)', r'\\\1', text)
-
-                metadata_file_content = ';FFMETADATA1\n'
-                for chapter in chapters:
-                    metadata_file_content += '[CHAPTER]\nTIMEBASE=1/1000\n'
-                    metadata_file_content += 'START=%d\n' % (chapter['start_time'] * 1000)
-                    metadata_file_content += 'END=%d\n' % (chapter['end_time'] * 1000)
-                    chapter_title = chapter.get('title')
-                    if chapter_title:
-                        metadata_file_content += 'title=%s\n' % ffmpeg_escape(chapter_title)
-                f.write(metadata_file_content)
-                in_filenames.append(metadata_filename)
-                options.extend(['-map_metadata', '1'])
-
-        self._downloader.to_screen('[ffmpeg] Adding metadata to \'%s\'' % filename)
-        self.run_ffmpeg_multiple_files(in_filenames, temp_filename, options)
-        if chapters:
-            os.remove(metadata_filename)
-        os.remove(encodeFilename(filename))
-        os.rename(encodeFilename(temp_filename), encodeFilename(filename))
-        return [], info
+            yield ('-attach', info['__infojson_filename'],
+                   '-metadata:s:%d' % new_stream, 'mimetype=application/json')
 
 
 class FFmpegMergerPP(FFmpegPostProcessor):
+    @PostProcessor._restrict_to(images=False)
     def run(self, info):
         filename = info['filepath']
         temp_filename = prepend_extension(filename, 'temp')
-        args = ['-c', 'copy', '-map', '0:v:0', '-map', '1:a:0']
-        self._downloader.to_screen('[ffmpeg] Merging formats into "%s"' % filename)
+        args = ['-c', 'copy']
+        audio_streams = 0
+        for (i, fmt) in enumerate(info['requested_formats']):
+            if fmt.get('acodec') != 'none':
+                args.extend(['-map', f'{i}:a:0'])
+                aac_fixup = fmt['protocol'].startswith('m3u8') and self.get_audio_codec(fmt['filepath']) == 'aac'
+                if aac_fixup:
+                    args.extend([f'-bsf:a:{audio_streams}', 'aac_adtstoasc'])
+                audio_streams += 1
+            if fmt.get('vcodec') != 'none':
+                args.extend(['-map', '%u:v:0' % (i)])
+        self.to_screen('Merging formats into "%s"' % filename)
         self.run_ffmpeg_multiple_files(info['__files_to_merge'], temp_filename, args)
         os.rename(encodeFilename(temp_filename), encodeFilename(filename))
         return info['__files_to_merge'], info
@@ -536,98 +754,120 @@ class FFmpegMergerPP(FFmpegPostProcessor):
                        'hypervideo will download single file media. '
                        'Update %s to version %s or newer to fix this.') % (
                            self.basename, self.basename, required_version)
-            if self._downloader:
-                self._downloader.report_warning(warning)
+            self.report_warning(warning)
             return False
         return True
 
 
-class FFmpegFixupStretchedPP(FFmpegPostProcessor):
-    def run(self, info):
-        stretched_ratio = info.get('stretched_ratio')
-        if stretched_ratio is None or stretched_ratio == 1:
-            return [], info
-
-        filename = info['filepath']
+class FFmpegFixupPostProcessor(FFmpegPostProcessor):
+    def _fixup(self, msg, filename, options):
         temp_filename = prepend_extension(filename, 'temp')
 
-        options = ['-c', 'copy', '-aspect', '%f' % stretched_ratio]
-        self._downloader.to_screen('[ffmpeg] Fixing aspect ratio in "%s"' % filename)
+        self.to_screen(f'{msg} of "{filename}"')
         self.run_ffmpeg(filename, temp_filename, options)
 
-        os.remove(encodeFilename(filename))
-        os.rename(encodeFilename(temp_filename), encodeFilename(filename))
+        os.replace(temp_filename, filename)
 
+
+class FFmpegFixupStretchedPP(FFmpegFixupPostProcessor):
+    @PostProcessor._restrict_to(images=False, audio=False)
+    def run(self, info):
+        stretched_ratio = info.get('stretched_ratio')
+        if stretched_ratio not in (None, 1):
+            self._fixup('Fixing aspect ratio', info['filepath'], [
+                '-c', 'copy', '-map', '0', '-dn', '-aspect', '%f' % stretched_ratio])
         return [], info
 
 
-class FFmpegFixupM4aPP(FFmpegPostProcessor):
+class FFmpegFixupM4aPP(FFmpegFixupPostProcessor):
+    @PostProcessor._restrict_to(images=False, video=False)
     def run(self, info):
-        if info.get('container') != 'm4a_dash':
-            return [], info
+        if info.get('container') == 'm4a_dash':
+            self._fixup('Correcting container', info['filepath'], [
+                '-c', 'copy', '-map', '0', '-dn', '-f', 'mp4'])
+        return [], info
 
-        filename = info['filepath']
-        temp_filename = prepend_extension(filename, 'temp')
 
-        options = ['-c', 'copy', '-f', 'mp4']
-        self._downloader.to_screen('[ffmpeg] Correcting container in "%s"' % filename)
-        self.run_ffmpeg(filename, temp_filename, options)
+class FFmpegFixupM3u8PP(FFmpegFixupPostProcessor):
+    @PostProcessor._restrict_to(images=False)
+    def run(self, info):
+        if self.get_audio_codec(info['filepath']) == 'aac':
+            self._fixup('Fixing malformed AAC bitstream', info['filepath'], [
+                '-c', 'copy', '-map', '0', '-dn', '-f', 'mp4', '-bsf:a', 'aac_adtstoasc'])
+        return [], info
 
-        os.remove(encodeFilename(filename))
-        os.rename(encodeFilename(temp_filename), encodeFilename(filename))
 
-        return [], info
+class FFmpegFixupTimestampPP(FFmpegFixupPostProcessor):
 
+    def __init__(self, downloader=None, trim=0.001):
+        # "trim" should be used when the video contains unintended packets
+        super(FFmpegFixupTimestampPP, self).__init__(downloader)
+        assert isinstance(trim, (int, float))
+        self.trim = str(trim)
 
-class FFmpegFixupM3u8PP(FFmpegPostProcessor):
+    @PostProcessor._restrict_to(images=False)
     def run(self, info):
-        filename = info['filepath']
-        if self.get_audio_codec(filename) == 'aac':
-            temp_filename = prepend_extension(filename, 'temp')
+        required_version = '4.4'
+        if is_outdated_version(self._versions[self.basename], required_version):
+            self.report_warning(
+                'A re-encode is needed to fix timestamps in older versions of ffmpeg. '
+                f'Please install ffmpeg {required_version} or later to fixup without re-encoding')
+            opts = ['-vf', 'setpts=PTS-STARTPTS']
+        else:
+            opts = ['-c', 'copy', '-bsf', 'setts=ts=TS-STARTPTS']
+        self._fixup('Fixing frame timestamp', info['filepath'], opts + ['-map', '0', '-dn', '-ss', self.trim])
+        return [], info
 
-            options = ['-c', 'copy', '-f', 'mp4', '-bsf:a', 'aac_adtstoasc']
-            self._downloader.to_screen('[ffmpeg] Fixing malformed AAC bitstream in "%s"' % filename)
-            self.run_ffmpeg(filename, temp_filename, options)
 
-            os.remove(encodeFilename(filename))
-            os.rename(encodeFilename(temp_filename), encodeFilename(filename))
+class FFmpegFixupDurationPP(FFmpegFixupPostProcessor):
+    @PostProcessor._restrict_to(images=False)
+    def run(self, info):
+        self._fixup('Fixing video duration', info['filepath'], ['-c', 'copy', '-map', '0', '-dn'])
         return [], info
 
 
 class FFmpegSubtitlesConvertorPP(FFmpegPostProcessor):
+    SUPPORTED_EXTS = ('srt', 'vtt', 'ass', 'lrc')
+
     def __init__(self, downloader=None, format=None):
         super(FFmpegSubtitlesConvertorPP, self).__init__(downloader)
         self.format = format
 
     def run(self, info):
         subs = info.get('requested_subtitles')
-        filename = info['filepath']
         new_ext = self.format
         new_format = new_ext
         if new_format == 'vtt':
             new_format = 'webvtt'
         if subs is None:
-            self._downloader.to_screen('[ffmpeg] There aren\'t any subtitles to convert')
+            self.to_screen('There aren\'t any subtitles to convert')
             return [], info
-        self._downloader.to_screen('[ffmpeg] Converting subtitles')
+        self.to_screen('Converting subtitles')
         sub_filenames = []
         for lang, sub in subs.items():
+            if not os.path.exists(sub.get('filepath', '')):
+                self.report_warning(f'Skipping embedding {lang} subtitle because the file is missing')
+                continue
             ext = sub['ext']
             if ext == new_ext:
-                self._downloader.to_screen(
-                    '[ffmpeg] Subtitle file for %s is already in the requested format' % new_ext)
+                self.to_screen('Subtitle file for %s is already in the requested format' % new_ext)
+                continue
+            elif ext == 'json':
+                self.to_screen(
+                    'You have requested to convert json subtitles into another format, '
+                    'which is currently not possible')
                 continue
-            old_file = subtitles_filename(filename, lang, ext, info.get('ext'))
+            old_file = sub['filepath']
             sub_filenames.append(old_file)
-            new_file = subtitles_filename(filename, lang, new_ext, info.get('ext'))
+            new_file = replace_extension(old_file, new_ext)
 
             if ext in ('dfxp', 'ttml', 'tt'):
-                self._downloader.report_warning(
+                self.report_warning(
                     'You have requested to convert dfxp (TTML) subtitles into another format, '
                     'which results in style information loss')
 
                 dfxp_file = old_file
-                srt_file = subtitles_filename(filename, lang, 'srt', info.get('ext'))
+                srt_file = replace_extension(old_file, 'srt')
 
                 with open(dfxp_file, 'rb') as f:
                     srt_data = dfxp2srt(f.read())
@@ -638,7 +878,8 @@ class FFmpegSubtitlesConvertorPP(FFmpegPostProcessor):
 
                 subs[lang] = {
                     'ext': 'srt',
-                    'data': srt_data
+                    'data': srt_data,
+                    'filepath': srt_file,
                 }
 
                 if new_ext == 'srt':
@@ -652,6 +893,125 @@ class FFmpegSubtitlesConvertorPP(FFmpegPostProcessor):
                 subs[lang] = {
                     'ext': new_ext,
                     'data': f.read(),
+                    'filepath': new_file,
                 }
 
+            info['__files_to_move'][new_file] = replace_extension(
+                info['__files_to_move'][sub['filepath']], new_ext)
+
         return sub_filenames, info
+
+
+class FFmpegSplitChaptersPP(FFmpegPostProcessor):
+    def __init__(self, downloader, force_keyframes=False):
+        FFmpegPostProcessor.__init__(self, downloader)
+        self._force_keyframes = force_keyframes
+
+    def _prepare_filename(self, number, chapter, info):
+        info = info.copy()
+        info.update({
+            'section_number': number,
+            'section_title': chapter.get('title'),
+            'section_start': chapter.get('start_time'),
+            'section_end': chapter.get('end_time'),
+        })
+        return self._downloader.prepare_filename(info, 'chapter')
+
+    def _ffmpeg_args_for_chapter(self, number, chapter, info):
+        destination = self._prepare_filename(number, chapter, info)
+        if not self._downloader._ensure_dir_exists(encodeFilename(destination)):
+            return
+
+        chapter['filepath'] = destination
+        self.to_screen('Chapter %03d; Destination: %s' % (number, destination))
+        return (
+            destination,
+            ['-ss', compat_str(chapter['start_time']),
+             '-t', compat_str(chapter['end_time'] - chapter['start_time'])])
+
+    @PostProcessor._restrict_to(images=False)
+    def run(self, info):
+        chapters = info.get('chapters') or []
+        if not chapters:
+            self.to_screen('Chapter information is unavailable')
+            return [], info
+
+        in_file = info['filepath']
+        if self._force_keyframes and len(chapters) > 1:
+            in_file = self.force_keyframes(in_file, (c['start_time'] for c in chapters))
+        self.to_screen('Splitting video by chapters; %d chapters found' % len(chapters))
+        for idx, chapter in enumerate(chapters):
+            destination, opts = self._ffmpeg_args_for_chapter(idx + 1, chapter, info)
+            self.real_run_ffmpeg([(in_file, opts)], [(destination, ['-c', 'copy'])])
+        if in_file != info['filepath']:
+            os.remove(in_file)
+        return [], info
+
+
+class FFmpegThumbnailsConvertorPP(FFmpegPostProcessor):
+    SUPPORTED_EXTS = ('jpg', 'png')
+
+    def __init__(self, downloader=None, format=None):
+        super(FFmpegThumbnailsConvertorPP, self).__init__(downloader)
+        self.format = format
+
+    @staticmethod
+    def is_webp(path):
+        with open(encodeFilename(path), 'rb') as f:
+            b = f.read(12)
+        return b[0:4] == b'RIFF' and b[8:] == b'WEBP'
+
+    def fixup_webp(self, info, idx=-1):
+        thumbnail_filename = info['thumbnails'][idx]['filepath']
+        _, thumbnail_ext = os.path.splitext(thumbnail_filename)
+        if thumbnail_ext:
+            thumbnail_ext = thumbnail_ext[1:].lower()
+            if thumbnail_ext != 'webp' and self.is_webp(thumbnail_filename):
+                self.to_screen('Correcting thumbnail "%s" extension to webp' % thumbnail_filename)
+                webp_filename = replace_extension(thumbnail_filename, 'webp')
+                os.replace(thumbnail_filename, webp_filename)
+                info['thumbnails'][idx]['filepath'] = webp_filename
+                info['__files_to_move'][webp_filename] = replace_extension(
+                    info['__files_to_move'].pop(thumbnail_filename), 'webp')
+
+    @staticmethod
+    def _options(target_ext):
+        if target_ext == 'jpg':
+            return ['-bsf:v', 'mjpeg2jpeg']
+        return []
+
+    def convert_thumbnail(self, thumbnail_filename, target_ext):
+        thumbnail_conv_filename = replace_extension(thumbnail_filename, target_ext)
+
+        self.to_screen('Converting thumbnail "%s" to %s' % (thumbnail_filename, target_ext))
+        self.real_run_ffmpeg(
+            [(thumbnail_filename, ['-f', 'image2', '-pattern_type', 'none'])],
+            [(thumbnail_conv_filename.replace('%', '%%'), self._options(target_ext))])
+        return thumbnail_conv_filename
+
+    def run(self, info):
+        files_to_delete = []
+        has_thumbnail = False
+
+        for idx, thumbnail_dict in enumerate(info['thumbnails']):
+            if 'filepath' not in thumbnail_dict:
+                continue
+            has_thumbnail = True
+            self.fixup_webp(info, idx)
+            original_thumbnail = thumbnail_dict['filepath']
+            _, thumbnail_ext = os.path.splitext(original_thumbnail)
+            if thumbnail_ext:
+                thumbnail_ext = thumbnail_ext[1:].lower()
+            if thumbnail_ext == 'jpeg':
+                thumbnail_ext = 'jpg'
+            if thumbnail_ext == self.format:
+                self.to_screen('Thumbnail "%s" is already in the requested format' % original_thumbnail)
+                continue
+            thumbnail_dict['filepath'] = self.convert_thumbnail(original_thumbnail, self.format)
+            files_to_delete.append(original_thumbnail)
+            info['__files_to_move'][thumbnail_dict['filepath']] = replace_extension(
+                info['__files_to_move'][original_thumbnail], self.format)
+
+        if not has_thumbnail:
+            self.to_screen('There aren\'t any thumbnails to convert')
+        return files_to_delete, info
diff --git a/hypervideo_dl/postprocessor/metadataparser.py b/hypervideo_dl/postprocessor/metadataparser.py
new file mode 100644
index 0000000..96aac9b
--- /dev/null
+++ b/hypervideo_dl/postprocessor/metadataparser.py
@@ -0,0 +1,116 @@
+import re
+
+from enum import Enum
+
+from .common import PostProcessor
+
+
+class MetadataParserPP(PostProcessor):
+    class Actions(Enum):
+        INTERPRET = 'interpretter'
+        REPLACE = 'replacer'
+
+    def __init__(self, downloader, actions):
+        PostProcessor.__init__(self, downloader)
+        self._actions = []
+        for f in actions:
+            action = f[0]
+            assert isinstance(action, self.Actions)
+            self._actions.append(getattr(self, action._value_)(*f[1:]))
+
+    @classmethod
+    def validate_action(cls, action, *data):
+        ''' Each action can be:
+                (Actions.INTERPRET, from, to) OR
+                (Actions.REPLACE, field, search, replace)
+        '''
+        if not isinstance(action, cls.Actions):
+            raise ValueError(f'{action!r} is not a valid action')
+        getattr(cls, action._value_)(cls, *data)
+
+    @staticmethod
+    def field_to_template(tmpl):
+        if re.match(r'[a-zA-Z_]+$', tmpl):
+            return f'%({tmpl})s'
+        return tmpl
+
+    @staticmethod
+    def format_to_regex(fmt):
+        r"""
+        Converts a string like
+           '%(title)s - %(artist)s'
+        to a regex like
+           '(?P<title>.+)\ \-\ (?P<artist>.+)'
+        """
+        if not re.search(r'%\(\w+\)s', fmt):
+            return fmt
+        lastpos = 0
+        regex = ''
+        # replace %(..)s with regex group and escape other string parts
+        for match in re.finditer(r'%\((\w+)\)s', fmt):
+            regex += re.escape(fmt[lastpos:match.start()])
+            regex += rf'(?P<{match.group(1)}>.+)'
+            lastpos = match.end()
+        if lastpos < len(fmt):
+            regex += re.escape(fmt[lastpos:])
+        return regex
+
+    def run(self, info):
+        for f in self._actions:
+            f(info)
+        return [], info
+
+    def interpretter(self, inp, out):
+        def f(info):
+            data_to_parse = self._downloader.evaluate_outtmpl(template, info)
+            self.write_debug(f'Searching for {out_re.pattern!r} in {template!r}')
+            match = out_re.search(data_to_parse)
+            if match is None:
+                self.report_warning(f'Could not interpret {inp!r} as {out!r}')
+                return
+            for attribute, value in match.groupdict().items():
+                info[attribute] = value
+                self.to_screen('Parsed %s from %r: %r' % (attribute, template, value if value is not None else 'NA'))
+
+        template = self.field_to_template(inp)
+        out_re = re.compile(self.format_to_regex(out))
+        return f
+
+    def replacer(self, field, search, replace):
+        def f(info):
+            val = info.get(field)
+            if val is None:
+                self.report_warning(f'Video does not have a {field}')
+                return
+            elif not isinstance(val, str):
+                self.report_warning(f'Cannot replace in field {field} since it is a {type(val).__name__}')
+                return
+            self.write_debug(f'Replacing all {search!r} in {field} with {replace!r}')
+            info[field], n = search_re.subn(replace, val)
+            if n:
+                self.to_screen(f'Changed {field} to: {info[field]}')
+            else:
+                self.to_screen(f'Did not find {search!r} in {field}')
+
+        search_re = re.compile(search)
+        return f
+
+
+class MetadataFromFieldPP(MetadataParserPP):
+    @classmethod
+    def to_action(cls, f):
+        match = re.match(r'(?P<in>.*?)(?<!\\):(?P<out>.+)$', f)
+        if match is None:
+            raise ValueError(f'it should be FROM:TO, not {f!r}')
+        return (
+            cls.Actions.INTERPRET,
+            match.group('in').replace('\\:', ':'),
+            match.group('out'))
+
+    def __init__(self, downloader, formats):
+        MetadataParserPP.__init__(self, downloader, [self.to_action(f) for f in formats])
+
+
+class MetadataFromTitlePP(MetadataParserPP):  # for backward compatibility
+    def __init__(self, downloader, titleformat):
+        MetadataParserPP.__init__(self, downloader, [(self.Actions.INTERPRET, 'title', titleformat)])
diff --git a/hypervideo_dl/postprocessor/modify_chapters.py b/hypervideo_dl/postprocessor/modify_chapters.py
new file mode 100644
index 0000000..a0818c4
--- /dev/null
+++ b/hypervideo_dl/postprocessor/modify_chapters.py
@@ -0,0 +1,336 @@
+import copy
+import heapq
+import os
+
+from .common import PostProcessor
+from .ffmpeg import (
+    FFmpegPostProcessor,
+    FFmpegSubtitlesConvertorPP
+)
+from .sponsorblock import SponsorBlockPP
+from ..utils import (
+    orderedSet,
+    PostProcessingError,
+    prepend_extension,
+)
+
+
+_TINY_CHAPTER_DURATION = 1
+DEFAULT_SPONSORBLOCK_CHAPTER_TITLE = '[SponsorBlock]: %(category_names)l'
+
+
+class ModifyChaptersPP(FFmpegPostProcessor):
+    def __init__(self, downloader, remove_chapters_patterns=None, remove_sponsor_segments=None, remove_ranges=None,
+                 *, sponsorblock_chapter_title=DEFAULT_SPONSORBLOCK_CHAPTER_TITLE, force_keyframes=False):
+        FFmpegPostProcessor.__init__(self, downloader)
+        self._remove_chapters_patterns = set(remove_chapters_patterns or [])
+        self._remove_sponsor_segments = set(remove_sponsor_segments or [])
+        self._ranges_to_remove = set(remove_ranges or [])
+        self._sponsorblock_chapter_title = sponsorblock_chapter_title
+        self._force_keyframes = force_keyframes
+
+    @PostProcessor._restrict_to(images=False)
+    def run(self, info):
+        chapters, sponsor_chapters = self._mark_chapters_to_remove(
+            info.get('chapters') or [], info.get('sponsorblock_chapters') or [])
+        if not chapters and not sponsor_chapters:
+            return [], info
+
+        real_duration = self._get_real_video_duration(info)
+        if not chapters:
+            chapters = [{'start_time': 0, 'end_time': real_duration, 'title': info['title']}]
+
+        info['chapters'], cuts = self._remove_marked_arrange_sponsors(chapters + sponsor_chapters)
+        if not cuts:
+            return [], info
+
+        if self._duration_mismatch(real_duration, info.get('duration')):
+            if not self._duration_mismatch(real_duration, info['chapters'][-1]['end_time']):
+                self.to_screen(f'Skipping {self.pp_key()} since the video appears to be already cut')
+                return [], info
+            if not info.get('__real_download'):
+                raise PostProcessingError('Cannot cut video since the real and expected durations mismatch. '
+                                          'Different chapters may have already been removed')
+            else:
+                self.write_debug('Expected and actual durations mismatch')
+
+        concat_opts = self._make_concat_opts(cuts, real_duration)
+
+        def remove_chapters(file, is_sub):
+            return file, self.remove_chapters(file, cuts, concat_opts, self._force_keyframes and not is_sub)
+
+        in_out_files = [remove_chapters(info['filepath'], False)]
+        in_out_files.extend(remove_chapters(in_file, True) for in_file in self._get_supported_subs(info))
+
+        # Renaming should only happen after all files are processed
+        files_to_remove = []
+        for in_file, out_file in in_out_files:
+            uncut_file = prepend_extension(in_file, 'uncut')
+            os.replace(in_file, uncut_file)
+            os.replace(out_file, in_file)
+            files_to_remove.append(uncut_file)
+
+        info['_real_duration'] = info['chapters'][-1]['end_time']
+        return files_to_remove, info
+
+    def _mark_chapters_to_remove(self, chapters, sponsor_chapters):
+        if self._remove_chapters_patterns:
+            warn_no_chapter_to_remove = True
+            if not chapters:
+                self.to_screen('Chapter information is unavailable')
+                warn_no_chapter_to_remove = False
+            for c in chapters:
+                if any(regex.search(c['title']) for regex in self._remove_chapters_patterns):
+                    c['remove'] = True
+                    warn_no_chapter_to_remove = False
+            if warn_no_chapter_to_remove:
+                self.to_screen('There are no chapters matching the regex')
+
+        if self._remove_sponsor_segments:
+            warn_no_chapter_to_remove = True
+            if not sponsor_chapters:
+                self.to_screen('SponsorBlock information is unavailable')
+                warn_no_chapter_to_remove = False
+            for c in sponsor_chapters:
+                if c['category'] in self._remove_sponsor_segments:
+                    c['remove'] = True
+                    warn_no_chapter_to_remove = False
+            if warn_no_chapter_to_remove:
+                self.to_screen('There are no matching SponsorBlock chapters')
+
+        sponsor_chapters.extend({
+            'start_time': start,
+            'end_time': end,
+            'category': 'manually_removed',
+            '_categories': [('manually_removed', start, end)],
+            'remove': True,
+        } for start, end in self._ranges_to_remove)
+
+        return chapters, sponsor_chapters
+
+    def _get_supported_subs(self, info):
+        for sub in (info.get('requested_subtitles') or {}).values():
+            sub_file = sub.get('filepath')
+            # The file might have been removed by --embed-subs
+            if not sub_file or not os.path.exists(sub_file):
+                continue
+            ext = sub['ext']
+            if ext not in FFmpegSubtitlesConvertorPP.SUPPORTED_EXTS:
+                self.report_warning(f'Cannot remove chapters from external {ext} subtitles; "{sub_file}" is now out of sync')
+                continue
+            # TODO: create __real_download for subs?
+            yield sub_file
+
+    def _remove_marked_arrange_sponsors(self, chapters):
+        # Store cuts separately, since adjacent and overlapping cuts must be merged.
+        cuts = []
+
+        def append_cut(c):
+            assert 'remove' in c
+            last_to_cut = cuts[-1] if cuts else None
+            if last_to_cut and last_to_cut['end_time'] >= c['start_time']:
+                last_to_cut['end_time'] = max(last_to_cut['end_time'], c['end_time'])
+            else:
+                cuts.append(c)
+            return len(cuts) - 1
+
+        def excess_duration(c):
+            # Cuts that are completely within the chapter reduce chapters' duration.
+            # Since cuts can overlap, excess duration may be less that the sum of cuts' durations.
+            # To avoid that, chapter stores the index to the fist cut within the chapter,
+            # instead of storing excess duration. append_cut ensures that subsequent cuts (if any)
+            # will be merged with previous ones (if necessary).
+            cut_idx, excess = c.pop('cut_idx', len(cuts)), 0
+            while cut_idx < len(cuts):
+                cut = cuts[cut_idx]
+                if cut['start_time'] >= c['end_time']:
+                    break
+                if cut['end_time'] > c['start_time']:
+                    excess += min(cut['end_time'], c['end_time'])
+                    excess -= max(cut['start_time'], c['start_time'])
+                cut_idx += 1
+            return excess
+
+        new_chapters = []
+
+        def append_chapter(c):
+            assert 'remove' not in c
+            length = c['end_time'] - c['start_time'] - excess_duration(c)
+            # Chapter is completely covered by cuts or sponsors.
+            if length <= 0:
+                return
+            start = new_chapters[-1]['end_time'] if new_chapters else 0
+            c.update(start_time=start, end_time=start + length)
+            new_chapters.append(c)
+
+        # Turn into a priority queue, index is a tie breaker.
+        # Plain stack sorted by start_time is not enough: after splitting the chapter,
+        # the part returned to the stack is not guaranteed to have start_time
+        # less than or equal to the that of the stack's head.
+        chapters = [(c['start_time'], i, c) for i, c in enumerate(chapters)]
+        heapq.heapify(chapters)
+
+        _, cur_i, cur_chapter = heapq.heappop(chapters)
+        while chapters:
+            _, i, c = heapq.heappop(chapters)
+            # Non-overlapping chapters or cuts can be appended directly. However,
+            # adjacent non-overlapping cuts must be merged, which is handled by append_cut.
+            if cur_chapter['end_time'] <= c['start_time']:
+                (append_chapter if 'remove' not in cur_chapter else append_cut)(cur_chapter)
+                cur_i, cur_chapter = i, c
+                continue
+
+            # Eight possibilities for overlapping chapters: (cut, cut), (cut, sponsor),
+            # (cut, normal), (sponsor, cut), (normal, cut), (sponsor, sponsor),
+            # (sponsor, normal), and (normal, sponsor). There is no (normal, normal):
+            # normal chapters are assumed not to overlap.
+            if 'remove' in cur_chapter:
+                # (cut, cut): adjust end_time.
+                if 'remove' in c:
+                    cur_chapter['end_time'] = max(cur_chapter['end_time'], c['end_time'])
+                # (cut, sponsor/normal): chop the beginning of the later chapter
+                # (if it's not completely hidden by the cut). Push to the priority queue
+                # to restore sorting by start_time: with beginning chopped, c may actually
+                # start later than the remaining chapters from the queue.
+                elif cur_chapter['end_time'] < c['end_time']:
+                    c['start_time'] = cur_chapter['end_time']
+                    c['_was_cut'] = True
+                    heapq.heappush(chapters, (c['start_time'], i, c))
+            # (sponsor/normal, cut).
+            elif 'remove' in c:
+                cur_chapter['_was_cut'] = True
+                # Chop the end of the current chapter if the cut is not contained within it.
+                # Chopping the end doesn't break start_time sorting, no PQ push is necessary.
+                if cur_chapter['end_time'] <= c['end_time']:
+                    cur_chapter['end_time'] = c['start_time']
+                    append_chapter(cur_chapter)
+                    cur_i, cur_chapter = i, c
+                    continue
+                # Current chapter contains the cut within it. If the current chapter is
+                # a sponsor chapter, check whether the categories before and after the cut differ.
+                if '_categories' in cur_chapter:
+                    after_c = dict(cur_chapter, start_time=c['end_time'], _categories=[])
+                    cur_cats = []
+                    for cat_start_end in cur_chapter['_categories']:
+                        if cat_start_end[1] < c['start_time']:
+                            cur_cats.append(cat_start_end)
+                        if cat_start_end[2] > c['end_time']:
+                            after_c['_categories'].append(cat_start_end)
+                    cur_chapter['_categories'] = cur_cats
+                    if cur_chapter['_categories'] != after_c['_categories']:
+                        # Categories before and after the cut differ: push the after part to PQ.
+                        heapq.heappush(chapters, (after_c['start_time'], cur_i, after_c))
+                        cur_chapter['end_time'] = c['start_time']
+                        append_chapter(cur_chapter)
+                        cur_i, cur_chapter = i, c
+                        continue
+                # Either sponsor categories before and after the cut are the same or
+                # we're dealing with a normal chapter. Just register an outstanding cut:
+                # subsequent append_chapter will reduce the duration.
+                cur_chapter.setdefault('cut_idx', append_cut(c))
+            # (sponsor, normal): if a normal chapter is not completely overlapped,
+            # chop the beginning of it and push it to PQ.
+            elif '_categories' in cur_chapter and '_categories' not in c:
+                if cur_chapter['end_time'] < c['end_time']:
+                    c['start_time'] = cur_chapter['end_time']
+                    c['_was_cut'] = True
+                    heapq.heappush(chapters, (c['start_time'], i, c))
+            # (normal, sponsor) and (sponsor, sponsor)
+            else:
+                assert '_categories' in c
+                cur_chapter['_was_cut'] = True
+                c['_was_cut'] = True
+                # Push the part after the sponsor to PQ.
+                if cur_chapter['end_time'] > c['end_time']:
+                    # deepcopy to make categories in after_c and cur_chapter/c refer to different lists.
+                    after_c = dict(copy.deepcopy(cur_chapter), start_time=c['end_time'])
+                    heapq.heappush(chapters, (after_c['start_time'], cur_i, after_c))
+                # Push the part after the overlap to PQ.
+                elif c['end_time'] > cur_chapter['end_time']:
+                    after_cur = dict(copy.deepcopy(c), start_time=cur_chapter['end_time'])
+                    heapq.heappush(chapters, (after_cur['start_time'], cur_i, after_cur))
+                    c['end_time'] = cur_chapter['end_time']
+                # (sponsor, sponsor): merge categories in the overlap.
+                if '_categories' in cur_chapter:
+                    c['_categories'] = cur_chapter['_categories'] + c['_categories']
+                # Inherit the cuts that the current chapter has accumulated within it.
+                if 'cut_idx' in cur_chapter:
+                    c['cut_idx'] = cur_chapter['cut_idx']
+                cur_chapter['end_time'] = c['start_time']
+                append_chapter(cur_chapter)
+                cur_i, cur_chapter = i, c
+        (append_chapter if 'remove' not in cur_chapter else append_cut)(cur_chapter)
+        return self._remove_tiny_rename_sponsors(new_chapters), cuts
+
+    def _remove_tiny_rename_sponsors(self, chapters):
+        new_chapters = []
+        for i, c in enumerate(chapters):
+            # Merge with the previous/next if the chapter is tiny.
+            # Only tiny chapters resulting from a cut can be skipped.
+            # Chapters that were already tiny in the original list will be preserved.
+            if (('_was_cut' in c or '_categories' in c)
+                    and c['end_time'] - c['start_time'] < _TINY_CHAPTER_DURATION):
+                if not new_chapters:
+                    # Prepend tiny chapter to the next one if possible.
+                    if i < len(chapters) - 1:
+                        chapters[i + 1]['start_time'] = c['start_time']
+                        continue
+                else:
+                    old_c = new_chapters[-1]
+                    if i < len(chapters) - 1:
+                        next_c = chapters[i + 1]
+                        # Not a typo: key names in old_c and next_c are really different.
+                        prev_is_sponsor = 'categories' in old_c
+                        next_is_sponsor = '_categories' in next_c
+                        # Preferentially prepend tiny normals to normals and sponsors to sponsors.
+                        if (('_categories' not in c and prev_is_sponsor and not next_is_sponsor)
+                                or ('_categories' in c and not prev_is_sponsor and next_is_sponsor)):
+                            next_c['start_time'] = c['start_time']
+                            continue
+                    old_c['end_time'] = c['end_time']
+                    continue
+
+            c.pop('_was_cut', None)
+            cats = c.pop('_categories', None)
+            if cats:
+                category = min(cats, key=lambda c: c[2] - c[1])[0]
+                cats = orderedSet(x[0] for x in cats)
+                c.update({
+                    'category': category,
+                    'categories': cats,
+                    'name': SponsorBlockPP.CATEGORIES[category],
+                    'category_names': [SponsorBlockPP.CATEGORIES[c] for c in cats]
+                })
+                c['title'] = self._downloader.evaluate_outtmpl(self._sponsorblock_chapter_title, c)
+                # Merge identically named sponsors.
+                if (new_chapters and 'categories' in new_chapters[-1]
+                        and new_chapters[-1]['title'] == c['title']):
+                    new_chapters[-1]['end_time'] = c['end_time']
+                    continue
+            new_chapters.append(c)
+        return new_chapters
+
+    def remove_chapters(self, filename, ranges_to_cut, concat_opts, force_keyframes=False):
+        in_file = filename
+        out_file = prepend_extension(in_file, 'temp')
+        if force_keyframes:
+            in_file = self.force_keyframes(in_file, (t for c in ranges_to_cut for t in (c['start_time'], c['end_time'])))
+        self.to_screen(f'Removing chapters from {filename}')
+        self.concat_files([in_file] * len(concat_opts), out_file, concat_opts)
+        if in_file != filename:
+            os.remove(in_file)
+        return out_file
+
+    @staticmethod
+    def _make_concat_opts(chapters_to_remove, duration):
+        opts = [{}]
+        for s in chapters_to_remove:
+            # Do not create 0 duration chunk at the beginning.
+            if s['start_time'] == 0:
+                opts[-1]['inpoint'] = f'{s["end_time"]:.6f}'
+                continue
+            opts[-1]['outpoint'] = f'{s["start_time"]:.6f}'
+            # Do not create 0 duration chunk at the end.
+            if s['end_time'] != duration:
+                opts.append({'inpoint': f'{s["end_time"]:.6f}'})
+        return opts
diff --git a/hypervideo_dl/postprocessor/movefilesafterdownload.py b/hypervideo_dl/postprocessor/movefilesafterdownload.py
new file mode 100644
index 0000000..1064a8c
--- /dev/null
+++ b/hypervideo_dl/postprocessor/movefilesafterdownload.py
@@ -0,0 +1,54 @@
+from __future__ import unicode_literals
+import os
+import shutil
+
+from .common import PostProcessor
+from ..utils import (
+    decodeFilename,
+    encodeFilename,
+    make_dir,
+    PostProcessingError,
+)
+
+
+class MoveFilesAfterDownloadPP(PostProcessor):
+
+    def __init__(self, downloader=None, downloaded=True):
+        PostProcessor.__init__(self, downloader)
+        self._downloaded = downloaded
+
+    @classmethod
+    def pp_key(cls):
+        return 'MoveFiles'
+
+    def run(self, info):
+        dl_path, dl_name = os.path.split(encodeFilename(info['filepath']))
+        finaldir = info.get('__finaldir', dl_path)
+        finalpath = os.path.join(finaldir, dl_name)
+        if self._downloaded:
+            info['__files_to_move'][info['filepath']] = decodeFilename(finalpath)
+
+        make_newfilename = lambda old: decodeFilename(os.path.join(finaldir, os.path.basename(encodeFilename(old))))
+        for oldfile, newfile in info['__files_to_move'].items():
+            if not newfile:
+                newfile = make_newfilename(oldfile)
+            if os.path.abspath(encodeFilename(oldfile)) == os.path.abspath(encodeFilename(newfile)):
+                continue
+            if not os.path.exists(encodeFilename(oldfile)):
+                self.report_warning('File "%s" cannot be found' % oldfile)
+                continue
+            if os.path.exists(encodeFilename(newfile)):
+                if self.get_param('overwrites', True):
+                    self.report_warning('Replacing existing file "%s"' % newfile)
+                    os.remove(encodeFilename(newfile))
+                else:
+                    self.report_warning(
+                        'Cannot move file "%s" out of temporary directory since "%s" already exists. '
+                        % (oldfile, newfile))
+                    continue
+            make_dir(newfile, PostProcessingError)
+            self.to_screen('Moving file "%s" to "%s"' % (oldfile, newfile))
+            shutil.move(oldfile, newfile)  # os.rename cannot move between volumes
+
+        info['filepath'] = finalpath
+        return [], info
diff --git a/hypervideo_dl/postprocessor/sponskrub.py b/hypervideo_dl/postprocessor/sponskrub.py
new file mode 100644
index 0000000..932555a
--- /dev/null
+++ b/hypervideo_dl/postprocessor/sponskrub.py
@@ -0,0 +1,96 @@
+from __future__ import unicode_literals
+import os
+import subprocess
+
+from .common import PostProcessor
+from ..compat import compat_shlex_split
+from ..utils import (
+    check_executable,
+    cli_option,
+    encodeArgument,
+    encodeFilename,
+    shell_quote,
+    str_or_none,
+    PostProcessingError,
+    prepend_extension,
+    process_communicate_or_kill,
+)
+
+
+# Deprecated in favor of the native implementation
+class SponSkrubPP(PostProcessor):
+    _temp_ext = 'spons'
+    _exe_name = 'sponskrub'
+
+    def __init__(self, downloader, path='', args=None, ignoreerror=False, cut=False, force=False):
+        PostProcessor.__init__(self, downloader)
+        self.force = force
+        self.cutout = cut
+        self.args = str_or_none(args) or ''  # For backward compatibility
+        self.path = self.get_exe(path)
+
+        if not ignoreerror and self.path is None:
+            if path:
+                raise PostProcessingError('sponskrub not found in "%s"' % path)
+            else:
+                raise PostProcessingError('sponskrub not found. Please install or provide the path using --sponskrub-path')
+
+    def get_exe(self, path=''):
+        if not path or not check_executable(path, ['-h']):
+            path = os.path.join(path, self._exe_name)
+            if not check_executable(path, ['-h']):
+                return None
+        return path
+
+    @PostProcessor._restrict_to(images=False)
+    def run(self, information):
+        if self.path is None:
+            return [], information
+
+        filename = information['filepath']
+        if not os.path.exists(encodeFilename(filename)):  # no download
+            return [], information
+
+        if information['extractor_key'].lower() != 'youtube':
+            self.to_screen('Skipping sponskrub since it is not a YouTube video')
+            return [], information
+        if self.cutout and not self.force and not information.get('__real_download', False):
+            self.report_warning(
+                'Skipping sponskrub since the video was already downloaded. '
+                'Use --sponskrub-force to run sponskrub anyway')
+            return [], information
+
+        self.to_screen('Trying to %s sponsor sections' % ('remove' if self.cutout else 'mark'))
+        if self.cutout:
+            self.report_warning('Cutting out sponsor segments will cause the subtitles to go out of sync.')
+            if not information.get('__real_download', False):
+                self.report_warning('If sponskrub is run multiple times, unintended parts of the video could be cut out.')
+
+        temp_filename = prepend_extension(filename, self._temp_ext)
+        if os.path.exists(encodeFilename(temp_filename)):
+            os.remove(encodeFilename(temp_filename))
+
+        cmd = [self.path]
+        if not self.cutout:
+            cmd += ['-chapter']
+        cmd += cli_option(self._downloader.params, '-proxy', 'proxy')
+        cmd += compat_shlex_split(self.args)  # For backward compatibility
+        cmd += self._configuration_args(self._exe_name, use_compat=False)
+        cmd += ['--', information['id'], filename, temp_filename]
+        cmd = [encodeArgument(i) for i in cmd]
+
+        self.write_debug('sponskrub command line: %s' % shell_quote(cmd))
+        pipe = None if self.get_param('verbose') else subprocess.PIPE
+        p = subprocess.Popen(cmd, stdout=pipe)
+        stdout = process_communicate_or_kill(p)[0]
+
+        if p.returncode == 0:
+            os.replace(temp_filename, filename)
+            self.to_screen('Sponsor sections have been %s' % ('removed' if self.cutout else 'marked'))
+        elif p.returncode == 3:
+            self.to_screen('No segments in the SponsorBlock database')
+        else:
+            msg = stdout.decode('utf-8', 'replace').strip() if stdout else ''
+            msg = msg.split('\n')[0 if msg.lower().startswith('unrecognised') else -1]
+            raise PostProcessingError(msg if msg else 'sponskrub failed with error code %s' % p.returncode)
+        return [], information
diff --git a/hypervideo_dl/postprocessor/sponsorblock.py b/hypervideo_dl/postprocessor/sponsorblock.py
new file mode 100644
index 0000000..7265a9d
--- /dev/null
+++ b/hypervideo_dl/postprocessor/sponsorblock.py
@@ -0,0 +1,96 @@
+import json
+import re
+from hashlib import sha256
+
+from .ffmpeg import FFmpegPostProcessor
+from ..compat import compat_urllib_parse_urlencode, compat_HTTPError
+from ..utils import PostProcessingError, network_exceptions, sanitized_Request
+
+
+class SponsorBlockPP(FFmpegPostProcessor):
+
+    EXTRACTORS = {
+        'Youtube': 'YouTube',
+    }
+    CATEGORIES = {
+        'sponsor': 'Sponsor',
+        'intro': 'Intermission/Intro Animation',
+        'outro': 'Endcards/Credits',
+        'selfpromo': 'Unpaid/Self Promotion',
+        'interaction': 'Interaction Reminder',
+        'preview': 'Preview/Recap',
+        'music_offtopic': 'Non-Music Section'
+    }
+
+    def __init__(self, downloader, categories=None, api='https://sponsor.ajay.app'):
+        FFmpegPostProcessor.__init__(self, downloader)
+        self._categories = tuple(categories or self.CATEGORIES.keys())
+        self._API_URL = api if re.match('^https?://', api) else 'https://' + api
+
+    def run(self, info):
+        extractor = info['extractor_key']
+        if extractor not in self.EXTRACTORS:
+            self.to_screen(f'SponsorBlock is not supported for {extractor}')
+            return [], info
+
+        info['sponsorblock_chapters'] = self._get_sponsor_chapters(info, info['duration'])
+        return [], info
+
+    def _get_sponsor_chapters(self, info, duration):
+        segments = self._get_sponsor_segments(info['id'], self.EXTRACTORS[info['extractor_key']])
+
+        def duration_filter(s):
+            start_end = s['segment']
+            # Ignore milliseconds difference at the start.
+            if start_end[0] <= 1:
+                start_end[0] = 0
+            # Ignore milliseconds difference at the end.
+            # Never allow the segment to exceed the video.
+            if duration and duration - start_end[1] <= 1:
+                start_end[1] = duration
+            # SponsorBlock duration may be absent or it may deviate from the real one.
+            return s['videoDuration'] == 0 or not duration or abs(duration - s['videoDuration']) <= 1
+
+        duration_match = [s for s in segments if duration_filter(s)]
+        if len(duration_match) != len(segments):
+            self.report_warning('Some SponsorBlock segments are from a video of different duration, maybe from an old version of this video')
+
+        def to_chapter(s):
+            (start, end), cat = s['segment'], s['category']
+            return {
+                'start_time': start,
+                'end_time': end,
+                'category': cat,
+                'title': self.CATEGORIES[cat],
+                '_categories': [(cat, start, end)]
+            }
+
+        sponsor_chapters = [to_chapter(s) for s in duration_match]
+        if not sponsor_chapters:
+            self.to_screen('No segments were found in the SponsorBlock database')
+        else:
+            self.to_screen(f'Found {len(sponsor_chapters)} segments in the SponsorBlock database')
+        return sponsor_chapters
+
+    def _get_sponsor_segments(self, video_id, service):
+        hash = sha256(video_id.encode('ascii')).hexdigest()
+        # SponsorBlock API recommends using first 4 hash characters.
+        url = f'{self._API_URL}/api/skipSegments/{hash[:4]}?' + compat_urllib_parse_urlencode({
+            'service': service,
+            'categories': json.dumps(self._categories),
+        })
+        for d in self._get_json(url):
+            if d['videoID'] == video_id:
+                return d['segments']
+        return []
+
+    def _get_json(self, url):
+        self.write_debug(f'SponsorBlock query: {url}')
+        try:
+            rsp = self._downloader.urlopen(sanitized_Request(url))
+        except network_exceptions as e:
+            if isinstance(e, compat_HTTPError) and e.code == 404:
+                return []
+            raise PostProcessingError(f'Unable to communicate with SponsorBlock API - {e}')
+
+        return json.loads(rsp.read().decode(rsp.info().get_param('charset') or 'utf-8'))
diff --git a/hypervideo_dl/postprocessor/xattrpp.py b/hypervideo_dl/postprocessor/xattrpp.py
index 814dabe..93acd6d 100644
--- a/hypervideo_dl/postprocessor/xattrpp.py
+++ b/hypervideo_dl/postprocessor/xattrpp.py
@@ -5,13 +5,13 @@ from ..compat import compat_os_name
 from ..utils import (
     hyphenate_date,
     write_xattr,
+    PostProcessingError,
     XAttrMetadataError,
     XAttrUnavailableError,
 )
 
 
 class XAttrMetadataPP(PostProcessor):
-
     #
     # More info about extended attributes for media:
     #   http://freedesktop.org/wiki/CommonExtendedAttributes/
@@ -27,7 +27,7 @@ class XAttrMetadataPP(PostProcessor):
         """ Set extended attributes on downloaded file (if xattr support is found). """
 
         # Write the metadata to the file's xattrs
-        self._downloader.to_screen('[metadata] Writing metadata to file\'s xattrs')
+        self.to_screen('Writing metadata to file\'s xattrs')
 
         filename = info['filepath']
 
@@ -58,16 +58,15 @@ class XAttrMetadataPP(PostProcessor):
             return [], info
 
         except XAttrUnavailableError as e:
-            self._downloader.report_error(str(e))
-            return [], info
+            raise PostProcessingError(str(e))
 
         except XAttrMetadataError as e:
             if e.reason == 'NO_SPACE':
-                self._downloader.report_warning(
+                self.report_warning(
                     'There\'s no disk space left, disk quota exceeded or filesystem xattr limit exceeded. '
                     + (('Some ' if num_written else '') + 'extended attributes are not written.').capitalize())
             elif e.reason == 'VALUE_TOO_LONG':
-                self._downloader.report_warning(
+                self.report_warning(
                     'Unable to write extended attributes due to too long values.')
             else:
                 msg = 'This filesystem doesn\'t support extended attributes. '
@@ -75,5 +74,5 @@ class XAttrMetadataPP(PostProcessor):
                     msg += 'You need to use NTFS.'
                 else:
                     msg += '(You may have to enable them in your /etc/fstab)'
-                self._downloader.report_error(msg)
+                raise PostProcessingError(str(e))
             return [], info