[MPlayer-users] How to create a "neutral sequence" at the beginning of a video track ?

[Nick Koretsky]

On Fri, 7 Aug 2015 12:16:03 +0000 (UTC)
André P. <csosog-at-yahoo.fr at ffmpeg.org> wrote:

> Is it possible to add a short "neutral sequence" (=short sequence of
> black -or white- stable image) at the begining or at the end of a video
> track with a command line program (ffmpeg, MEncoder, mkvtoolnix
> collection or other) ? I am looking for the video equivalent of the "pad"
> parameter of the sox audio editor but would accept a more complex
> procedure. 
> 
> Notice that creating a "neutral sequence" with 
> ffmpeg -i {original file} -t {some seconds} -vf
> "fade=t=in:st=600:d=0.5" {neutral sequence} is not a satisfactory
> solution because the {neutral sequence} may not be concatenated to the
> {original file} because the caracteristics (codec,...) of the created
> {neutral sequence} usually differ from those of the {original
> file}. 

What you are asking for is impossible in a general case. To add
something to a video track without reencode depending on a file format and
codecs used you will need to at least encode your sequence with the same
codec as your file, at worst you would have to match exact codec
parameters. If you are asking if there is a commandline tool capable to
automatically analyze input file, encode desired sequence using the right
parameters and append it to input then i am not aware of anything even
remotely close.



-- 
  Nick Koretsky (nick.koretsky at gmail.com)