[FFmpeg-user] How do I create an ffmpeg command line?

[Noeck]

Hi Mark,

you are pretty close:

> What I've concluded from what I've read (and seen on this list):
>
> 'ffmpeg [gen_opts] [in_opts] -i <infile> [out_opts] <outfile>'

Yes, and it's documented like that at the start of the documentation:

http://ffmpeg.org/ffmpeg.html#Synopsis

  ffmpeg [global_options] {[input_file_options] -i input_url} ...
  {[output_file_options] output_url} ...

Then the detailed description ramps up quite steeply …

> And I've read about filter graphs of course, but it's awfully cryptic
> and there's no use examples. I know that filter invocation involves
> operators such as '[x:y]' but I've not figured out what they symbolize
> and how to use them in a command line -- I've tried dozens and dozens of
> hacks.

http://ffmpeg.org/ffmpeg.html#Advanced-options

  5.11 *Advanced options*

  Input link labels must refer to input streams using the
  [file_index:stream_specifier] syntax (i.e. the same as -map uses). If
  stream_specifier matches multiple streams, the first one will be used.
  An unlabeled input will be connected to the first unused input stream
  of the matching type.

HTH,
Daniel