[cleanup] Refactor ffmpeg convertors

1 files changed, 26 insertions, 23 deletions

diff --git a/yt_dlp/postprocessor/ffmpeg.py b/yt_dlp/postprocessor/ffmpeg.py
index 810c9cb86..ea728be37 100644
--- a/yt_dlp/postprocessor/ffmpeg.py
+++ b/yt_dlp/postprocessor/ffmpeg.py
@@ -290,13 +290,12 @@ class FFmpegPostProcessor(PostProcessor):
 
 
 class FFmpegExtractAudioPP(FFmpegPostProcessor):
-    COMMON_AUDIO_EXTENSIONS = ('wav', 'flac', 'm4a', 'aiff', 'mp3', 'ogg', 'mka', 'opus', 'wma')
+    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
 
@@ -315,7 +314,7 @@ class FFmpegExtractAudioPP(FFmpegPostProcessor):
         path = information['filepath']
         orig_ext = information['ext']
 
-        if self._preferredcodec == 'best' and orig_ext in self.COMMON_AUDIO_EXTENSIONS:
+        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
 
@@ -400,6 +399,8 @@ 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):
@@ -419,14 +420,14 @@ class FFmpegVideoConvertorPP(FFmpegPostProcessor):
         return []
 
     def run(self, information):
-        path = information['filepath']
-        target_ext = self._target_ext(information['ext'].lower())
+        path, source_ext = information['filepath'], information['ext'].lower()
+        target_ext = self._target_ext(source_ext)
         _skip_msg = (
             'could not find a mapping for %s' if not target_ext
             else 'already is in target format %s' if source_ext == target_ext
             else None)
         if _skip_msg:
-            self.to_screen('Not %s media file %s; %s' % (self._action, path, _skip_msg % source_ext))
+            self.to_screen('Not %s media file "%s"; %s' % (self._action, path, _skip_msg % source_ext))
             return [], information
 
         prefix, sep, oldext = path.rpartition('.')
@@ -708,6 +709,8 @@ class FFmpegFixupM3u8PP(FFmpegPostProcessor):
 
 
 class FFmpegSubtitlesConvertorPP(FFmpegPostProcessor):
+    SUPPORTED_EXTS = ('srt', 'vtt', 'ass', 'lrc')
+
     def __init__(self, downloader=None, format=None):
         super(FFmpegSubtitlesConvertorPP, self).__init__(downloader)
         self.format = format
@@ -816,6 +819,8 @@ class FFmpegSplitChaptersPP(FFmpegPostProcessor):
 
 
 class FFmpegThumbnailsConvertorPP(FFmpegPostProcessor):
+    SUPPORTED_EXTS = ('jpg', 'png')
+
     def __init__(self, downloader=None, format=None):
         super(FFmpegThumbnailsConvertorPP, self).__init__(downloader)
         self.format = format
@@ -841,31 +846,29 @@ class FFmpegThumbnailsConvertorPP(FFmpegPostProcessor):
                 info['__files_to_move'][webp_filename] = replace_extension(
                     info['__files_to_move'].pop(thumbnail_filename), 'webp')
 
-    def convert_thumbnail(self, thumbnail_filename, ext):
-        if ext == 'jpg':
-            format_name = 'JPEG'
-            opts = ['-bsf:v', 'mjpeg2jpeg']
-        elif ext == 'png':
-            format_name = 'PNG'
-            opts = []
-        else:
-            raise FFmpegPostProcessorError('Only conversion to either jpg or png is currently supported')
+    @staticmethod
+    def _options(target_ext):
+        if target_ext == 'jpg':
+            return ['-bsf:v', 'mjpeg2jpeg']
+        return []
+
+    def convert_thumbnail(self, thumbnail_filename, target_ext):
         # 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_conv_filename = replace_extension(escaped_thumbnail_filename, ext)
-        self.to_screen('Converting thumbnail "%s" to %s' % (escaped_thumbnail_filename, format_name))
-        self.run_ffmpeg(escaped_thumbnail_filename, escaped_thumbnail_conv_filename, opts)
-        thumbnail_conv_filename = replace_extension(thumbnail_filename, ext)
+        escaped_thumbnail_conv_filename = replace_extension(escaped_thumbnail_filename, target_ext)
+
+        self.to_screen('Converting thumbnail "%s" to %s' % (escaped_thumbnail_filename, target_ext))
+        self.run_ffmpeg(escaped_thumbnail_filename, escaped_thumbnail_conv_filename, self._options(target_ext))
+
         # Rename back to unescaped
+        thumbnail_conv_filename = replace_extension(thumbnail_filename, target_ext)
         os.rename(encodeFilename(escaped_thumbnail_filename), encodeFilename(thumbnail_filename))
         os.rename(encodeFilename(escaped_thumbnail_conv_filename), encodeFilename(thumbnail_conv_filename))
         return thumbnail_conv_filename
 
     def run(self, info):
-        if self.format not in ('jpg', 'png'):
-            raise FFmpegPostProcessorError('Only conversion to either jpg or png is currently supported')
         files_to_delete = []
         has_thumbnail = False