[FFmpeg-devel] [PATCH 5/6] fftools/ffmpeg: support applying container level cropping

[Anton Khirnov]

Quoting James Almer (2024-05-29 23:46:31)
> @@ -254,6 +256,11 @@ typedef struct InputFilterOptions {
>       * accurate */
>      AVRational          framerate;
>  
> +    unsigned crop_top;
> +    unsigned crop_bottom;
> +    unsigned crop_left;
> +    unsigned crop_right;

breaks vertical alignment

> +
>      int                 sub2video_width;
>      int                 sub2video_height;
>  
> diff --git a/fftools/ffmpeg_demux.c b/fftools/ffmpeg_demux.c
> index 1ca8d804ae..4178b8f840 100644
> --- a/fftools/ffmpeg_demux.c
> +++ b/fftools/ffmpeg_demux.c
> @@ -66,6 +66,7 @@ typedef struct DemuxStream {
>      int                      have_sub2video;
>      int                      reinit_filters;
>      int                      autorotate;
> +    int                      apply_cropping;
>  
>  
>      int                      wrap_correction_done;
> @@ -1000,11 +1001,20 @@ int ist_filter_add(InputStream *ist, InputFilter *ifilter, int is_simple,
>      ist->filters[ist->nb_filters - 1] = ifilter;
>  
>      if (ist->par->codec_type == AVMEDIA_TYPE_VIDEO) {
> +        const AVPacketSideData *sd = av_packet_side_data_get(ist->st->codecpar->coded_side_data,
> +                                                             ist->st->codecpar->nb_coded_side_data,
> +                                                             AV_PKT_DATA_FRAME_CROPPING);
>          if (ist->framerate.num > 0 && ist->framerate.den > 0) {
>              opts->framerate = ist->framerate;
>              opts->flags |= IFILTER_FLAG_CFR;
>          } else
>              opts->framerate = av_guess_frame_rate(d->f.ctx, ist->st, NULL);
> +        if (sd && sd->size == sizeof(uint32_t) * 4) {

better make it <= to account for future extensions, e.g. we might want
to add sub-pixel resolution in there

> diff --git a/fftools/ffmpeg_opt.c b/fftools/ffmpeg_opt.c
> index 910e4a336b..0c50ce16ba 100644
> --- a/fftools/ffmpeg_opt.c
> +++ b/fftools/ffmpeg_opt.c
> @@ -1732,6 +1732,9 @@ const OptionDef options[] = {
>      { "autoscale",                  OPT_TYPE_BOOL,   OPT_PERSTREAM | OPT_EXPERT | OPT_OUTPUT,
>          { .off = OFFSET(autoscale) },
>          "automatically insert a scale filter at the end of the filter graph" },
> +    { "apply_cropping",             OPT_TYPE_BOOL,   OPT_PERSTREAM | OPT_EXPERT | OPT_INPUT,
> +        { .off = OFFSET(apply_cropping) },
> +        "apply frame cropping" },

Apply container-level cropping (in addition to codec-level cropping)

Also, missing docs.

-- 
Anton Khirnov