Experimental override option for output args

youtube_dl/__init__.py

@@ -310,6 +310,9 @@ def _real_main(argv=None):
     postprocessor_args = None
     if opts.postprocessor_args:
         postprocessor_args = compat_shlex_split(opts.postprocessor_args)
+    ffmpeg_out_override = None
+    if opts.ffmpeg_out_override:
+        ffmpeg_out_override = compat_shlex_split(opts.ffmpeg_out_override)
     match_filter = (
         None if opts.match_filter is None
         else match_filter_func(opts.match_filter))
@@ -427,6 +430,7 @@ def _real_main(argv=None):
         'hls_prefer_native': opts.hls_prefer_native,
         'hls_use_mpegts': opts.hls_use_mpegts,
         'external_downloader_args': external_downloader_args,
+        'ffmpeg_out_override': ffmpeg_out_override,
         'postprocessor_args': postprocessor_args,
         'cn_verification_proxy': opts.cn_verification_proxy,
         'geo_verification_proxy': opts.geo_verification_proxy,

youtube_dl/downloader/external.py

@@ -311,7 +311,10 @@ class FFmpegFD(ExternalFD):
             elif isinstance(conn, compat_str):
                 args += ['-rtmp_conn', conn]
 
-        args += ['-i', url, '-c', 'copy']
+        args += ['-i', url]
+
+        ffmpeg_out_override = self.params.get('ffmpeg_out_override')
+        args += ffmpeg_out_override if ffmpeg_out_override else ['-c', 'copy']
 
         if self.params.get('test', False):
             args += ['-fs', compat_str(self._TEST_FILE_SIZE)]

youtube_dl/options.py

@@ -525,6 +525,10 @@ def parseOpts(overrideArguments=None):
         '--external-downloader-args',
         dest='external_downloader_args', metavar='ARGS',
         help='Give these arguments to the external downloader')
+    downloader.add_option(
+        '--ffmpeg-out-override',
+        dest='ffmpeg_out_override', metavar='ARGS',
+        help='Give these arguments to the ffmpeg instead of `-c copy`')
 
     workarounds = optparse.OptionGroup(parser, 'Workarounds')
     workarounds.add_option(