[FFmpeg-devel] [PATCH] doc/ffmpeg: mention how to pass options to loopback decoders

[Stefano Sabatini]

On date Thursday 2024-03-14 11:12:31 +0100, Anton Khirnov wrote:
> ---
>  doc/ffmpeg.texi | 14 ++++++++++----
>  1 file changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/doc/ffmpeg.texi b/doc/ffmpeg.texi
> index a38ef834e1..801c083705 100644
> --- a/doc/ffmpeg.texi
> +++ b/doc/ffmpeg.texi
> @@ -229,12 +229,16 @@ successive integers starting at zero. These indices should then be used to refer
>  to loopback decoders in complex filtergraph link labels, as described in the
>  documentation for @option{-filter_complex}.
>  

> +Decoding AVOptions can be passed to loopback decoders by placing them before

AVOptions => options (rationale: we have only a few references to
AVOptions and no direct ones in ffmpeg.texi, and there is no need to
assume arbitrary AV/FF jargon).

> + at code{-dec}, analogously to input/output options.
> +
>  E.g. the following example:
>  
>  @example
>  ffmpeg -i INPUT                                        \
>    -map 0:v:0 -c:v libx264 -crf 45 -f null -            \
> -  -dec 0:0 -filter_complex '[0:v][dec:0]hstack[stack]' \
> +  -threads 3 -dec 0:0                                  \
> +  -filter_complex '[0:v][dec:0]hstack[stack]'          \
>    -map '[stack]' -c:v ffv1 OUTPUT
>  @end example
>  
> @@ -244,11 +248,13 @@ reads an input video and
>  (line 2) encodes it with @code{libx264} at low quality;
>  
>  @item
> -(line 3) decodes this encoded stream and places it side by side with the
> -original input video;
> +(line 3) decodes this encoded stream using 3 threads;
>  
>  @item
> -(line 4) combined video is then losslessly encoded and written into
> +(line 4) places decoded video side by side with the original input video;
> +
> + at item
> +(line 5) combined video is then losslessly encoded and written into
>  @file{OUTPUT}.

LGTM otherwise, thanks.