Dear Mark, Thank you for your reply. But I'm looking at the syntax of Stream specifiers. It clearly specifies 7 forms.
1. stream_index 2. stream_type[:additional_stream_specifier] 3. g:group_specifier[:additional_stream_specifier] 4. p:program_id[:additional_stream_specifier] 5. #stream_id or i:stream_id 6. m:key[:value] 7. u 0:1 fits none of the 7 forms. [LOW] fits none of the 7 forms. I wonder is it a documentation bug that it misses other forms of specifiers, or do I misunderstand something? Mark Filipak <markfilipak.i...@gmail.com> 於 2024年7月25日 週四 下午2:46寫道： > On 25/07/2024 00.56, gqqnb2005 wrote: > > Basically, I want to figure out how to specify streams for the option > -map, > > -codec, and -filter_complex. > > > > ffmpeg -i INPUT -map 0:1 out.wav > > > > Is 0:1 a stream specifier ( > > https://ffmpeg.org//ffmpeg.html#Stream-specifiers-1)? Which form is it? > > Yes. Input 0, stream 1 (i.e., the 2nd stream, of any type). 'map' wires > things to the output. No > 'map', no output. > > ffmpeg -i INPUT -map 0 -c copy -c:v:1 libx264 -c:a:137 libvorbis OUTPUT > > > > v:1 and a:137 seem to follow the syntax of stream specifier because a > and v > > are stream_type. > > Yes, the 2nd video stream. There can't be 138 audio streams, so that has > to be wrong. > > > ffmpeg -i in.flac -filter_complex 'acrossover=split=1500[LOW][HIGH]' -map > > '[LOW]' low.wav -map '[HIGH]' high.wav > > > > Is '[LOW]' in the syntax of stream specifier? > > In a sense, yes. It's a 'plug'. You connect plugs within a filter complex > and to the output 'map' > like they are physical equipment. > > --Mark. > > > _______________________________________________ > ffmpeg-user mailing list > ffmpeg-user@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-user > > To unsubscribe, visit link above, or email > ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe". > _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
