[FFmpeg-user] Strange mapping/tagging/stream correlation behavior

Christian plymouth78 at googlemail.com
Thu Jun 21 22:46:38 CEST 2012


2012/6/21 Mike Scheutzow <mike.scheutzow at alcatel-lucent.com>:

>> [localhost:/Volumes/Various/Movies]% ffmpeg -i movie.mkv -i movie.mkv
>> -c:v:0:0 copy -c:a:0:1 libfaac -c:a:1:1 ac3 -tag:0 avc1 -tag:1 mp4a
>> -tag:2 ac-3 -map 0:0 -map 1:1 -map 0:1 movie.m4v
> Your first problem is that the -c index value uses *output* stream numbers.

Those number should mean -c:a:file-index:stream-index. The stream-index
were out of the input-files/streams.

> And secondly, the command line documentation gives no indication that two
> numbers are permitted.

Oh, does that mean that the documentation under "2. Description" ("To refer to
input files in options, you must use their indices (0-based). E.g. the
first input
file is 0, the second is 1 etc. Similarly, streams within a file are
referred to by
their indices. E.g. 2:3 refers to the fourth stream in the third input
file. See also
the Stream specifiers chapter.") shouldn't be understood for all options?

So I guess then that the right codec options have to placed right
after the input
file they refer to? Have to try this.

> The -map option uses *input* stream numbers, and must be specified in the
> order: map-for-out-stream-0, map-for-out-stream-1, etc.

That's what I did and understood, but as you can see from my example it didn't


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