This option also has a few special uses:
* You can download an additional URL based on the metadata of the currently downloaded video. To do this, set the field `additional_urls` to the URL that you want to download. Eg: `--parse-metadata "description:(?P<additional_urls>https?://www\.vimeo\.com/\d+)` will download the first vimeo video found in the description
-* You can use this to change the metadata that is embedded in the media file. To do this, set the value of the corresponding field with a `meta_` prefix. For example, any value you set to `meta_description` field will be added to the `description` field in the file. For example, you can use this to set a different "description" and "synopsis". Any value set to the `meta_` field will overwrite all default values.
+* You can use this to change the metadata that is embedded in the media file. To do this, set the value of the corresponding field with a `meta_` prefix. For example, any value you set to `meta_description` field will be added to the `description` field in the file. For example, you can use this to set a different "description" and "synopsis". To modify the metadata of individual streams, use the `meta<n>_` prefix (Eg: `meta1_language`). Any value set to the `meta_` field will overwrite all default values.
For reference, these are the fields yt-dlp adds by default to the file metadata:
from __future__ import unicode_literals
+import collections
import io
import itertools
import os
yield ('-map_metadata', '1')
def _get_metadata_opts(self, info):
- metadata = {}
- meta_prefix = 'meta_'
+ meta_prefix = 'meta'
+ metadata = collections.defaultdict(dict)
def add(meta_list, info_list=None):
value = next((
- str(info[key]) for key in [meta_prefix] + list(variadic(info_list or meta_list))
+ str(info[key]) for key in [f'{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)})
+ metadata['common'].update({meta_f: value for meta_f in variadic(meta_list)})
# See [1-4] for some info on media metadata/metadata supported
# by ffmpeg.
add('episode_sort', 'episode_number')
if 'embed-metadata' in self.get_param('compat_opts', []):
add('comment', 'description')
- metadata.pop('synopsis', None)
+ metadata['common'].pop('synopsis', None)
+ meta_regex = rf'{re.escape(meta_prefix)}(?P<i>\d+)?_(?P<key>.+)'
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
+ mobj = re.fullmatch(meta_regex, key)
+ if value is not None and mobj:
+ metadata[mobj.group('i') or 'common'][mobj.group('key')] = value
- for name, value in metadata.items():
+ for name, value in metadata['common'].items():
yield ('-metadata', f'{name}={value}')
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)
+ lang = ISO639Utils.short2long(fmt['language']) or fmt.get('language')
+ for i in range(stream_idx, stream_idx + stream_count):
+ if lang:
+ metadata[str(i)].setdefault('language', lang)
+ for name, value in metadata[str(i)].items():
+ yield (f'-metadata:s:{i}', f'{name}={value}')
stream_idx += stream_count
def _get_infojson_opts(self, info, infofn):