[FFmpeg-user] Ffmpeg - h filter

[Paul B Mahol]

You should never parse textual output of -h help.

If you need to get options of filter use library provided API.

On 1/21/20, James Northrup <jim at vsiwest.com> wrote:
> i am maintaining ffblockly which scrapes the ffmpeg executable for filter
> parameters and defaults by cartesian product of e.g. >>>(below)
>
> is there a build step artifact that more cleanly has the  self-doc
> records?  this cmdline help has changed ever so slightly and i've got to
> reverse engineer again.  my initial look into the build process turned up
> nothing conclusive, maybe some hints to get me started looking in the right
> place
>
>>>>(below)
> ffmpeg -h filter=crop 2>/dev/null
> Filter crop
>  Crop the input video.
>    Inputs:
>       #0: default (video)
>    Outputs:
>       #0: default (video)
> crop AVOptions:
>  out_w             <string>     ..FV.....T set the width crop area
> expression (default "iw")
>  w                 <string>     ..FV.....T set the width crop area
> expression (default "iw")
>  out_h             <string>     ..FV.....T set the height crop area
> expression (default "ih")
>  h                 <string>     ..FV.....T set the height crop area
> expression (default "ih")
>  x                 <string>     ..FV.....T set the x crop area expression
> (default "(in_w-out_w)/2")
>  y                 <string>     ..FV.....T set the y crop area expression
> (default "(in_h-out_h)/2")
>  keep_aspect       <boolean>    ..FV...... keep aspect ratio (default
> false)
>  exact             <boolean>    ..FV...... do exact cropping (default false)
> _______________________________________________
> ffmpeg-user mailing list
> ffmpeg-user at ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-user
>
> To unsubscribe, visit link above, or email
> ffmpeg-user-request at ffmpeg.org with subject "unsubscribe".