[FFmpeg-user] Syntax request for -vf to copy /pass through video stream

[Stefano Sabatini]

On date Thursday 2013-10-31 12:47:40 -0500, David Favor wrote:
> Stefano Sabatini wrote:
> >On date Thursday 2013-10-31 12:31:59 -0500, David Favor wrote:
> >>Stefano Sabatini wrote:
> >>>On date Thursday 2013-10-31 12:20:26 -0500, David Favor wrote:
> >>>[...]
> >>>>+ ffmpeg -y -i broken.mp4 -c:a copy -vf copy -vf setdar=dar=0 -vf setsar=sar=0 -t 10 vfcopy.mp4
> >>>This command is broken in several ways, first you can't copy and
> >>>filter at the same time, and multiple -vf a -vf b -vf c have the
> >>>effect of the last -vf command (in this case -vf c).
> >>>
> >>>Please understand the meaning of the syntax and that you *CAN'T* copy
> >>>a stream and filter it at the same time.
> >
> >>So -v:c copy and -vf copy are effectively the same.
> >
> >No, you're mixing two different things (and "-v:c" should be "-c:v"),
> >bitstream copy (to copy a stream from input to output stream with no
> >decoding and encoding) and copying data at the filtering level
> >(working with a decoded video stream).
> 
> According to http://ffmpeg.org/ffmpeg.html there is only -c:v (codec video).
> There is no -v:c... so this is correct...
> 
> ffmpeg -y -i broken.mp4 -c:v copy -c:a copy -t 10 foo.mp4
> 
> and this is incorrect...
> 

> ffmpeg -y -i broken.mp4 -v:c copy -c:a copy -t 10 foo.mp4 (which produces...)
> Invalid loglevel "copy". Possible levels are numbers or:
> "quiet"
> "panic"
> "fatal"
> "error"
> "warning"
> "info"
> "verbose"
> "debug"

-v is an alias for -loglevel.

> >>So there's no real way to copy (bit for bit) a video stream and
> >>change SAR or DAR...
> >
> >There is the -aspect command if you want to bitstream-copy and change
> >the aspect ratio in the output container.
> 
> Doing something like the following has no effect on SAR + DAR...
> 

> ffmpeg -y -i broken.mp4 -c:a copy -c:v copy -aspect 16:9 -t 10 foo.mp4
> 
> [SAR 64757:64800 DAR 319:180] is same in both input + output video, so
> container aspect ratio [SAR] has not been effected.

Show the commandline output.
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