[FFmpeg-devel] [PATCH 4/4 v3] avcodec/av1dec: add an option to select an operating point

[Mark Thompson]

On 15/11/2020 21:55, James Almer wrote:
> Signed-off-by: James Almer <jamrial at gmail.com>
> ---
>   doc/decoders.texi   | 13 +++++++++++++
>   libavcodec/av1dec.c | 30 ++++++++++++++++++++++++++++++
>   libavcodec/av1dec.h |  4 ++++
>   3 files changed, 47 insertions(+)
> 
> diff --git a/doc/decoders.texi b/doc/decoders.texi
> index bfab562fb2..27c6ba4a5d 100644
> --- a/doc/decoders.texi
> +++ b/doc/decoders.texi
> @@ -25,6 +25,19 @@ enabled decoders.
>   A description of some of the currently available video decoders
>   follows.
>   
> + at section av1
> +
> +AOMedia Video 1 (AV1) decoder.
> +
> + at subsection Options
> +
> + at table @option
> +
> + at item operating_point
> +Select an operating point of a scalable AV1 bitstream (0 - 31). Default is 0.
> +
> + at end table
> +
>   @section rawvideo
>   
>   Raw video decoder.
> diff --git a/libavcodec/av1dec.c b/libavcodec/av1dec.c
> index c1967f03bd..b7ee307159 100644
> --- a/libavcodec/av1dec.c
> +++ b/libavcodec/av1dec.c
> @@ -19,6 +19,7 @@
>    */
>   
>   #include "libavutil/pixdesc.h"
> +#include "libavutil/opt.h"
>   #include "avcodec.h"
>   #include "av1dec.h"
>   #include "bytestream.h"
> @@ -615,6 +616,8 @@ static av_cold int av1_decode_init(AVCodecContext *avctx)
>       if (ret < 0)
>           return ret;
>   
> +    av_opt_set_int(s->cbc->priv_data, "operating_point", s->operating_point, 0);
> +
>       if (avctx->extradata && avctx->extradata_size) {
>           ret = ff_cbs_read(s->cbc, &s->current_obu, avctx->extradata,
>                             avctx->extradata_size);
> @@ -704,6 +707,11 @@ static int set_output_frame(AVCodecContext *avctx, AVFrame *frame,
>       const AVFrame *srcframe = s->cur_frame.tf.f;
>       int ret;
>   
> +    // TODO: all layers
> +    if (s->operating_point_idc &&
> +        av_log2(s->operating_point_idc >> 8) > s->cur_frame.spatial_id)
> +        return 0;

I'm confused by what this is doing.  Shouldn't it be checking that the spatial_id is in the mask, rather than a numerical comparison?

Also, what about temporal_id?

> +
>       ret = av_frame_ref(frame, srcframe);
>       if (ret < 0)
>           return ret;
> @@ -809,6 +817,8 @@ static int av1_decode_frame(AVCodecContext *avctx, void *frame,
>                   goto end;
>               }
>   
> +            s->operating_point_idc = s->raw_seq->operating_point_idc[s->operating_point];
> +
>               if (s->pix_fmt == AV_PIX_FMT_NONE) {
>                   ret = get_pixel_format(avctx);
>                   if (ret < 0) {
> @@ -888,6 +898,9 @@ static int av1_decode_frame(AVCodecContext *avctx, void *frame,
>               s->cur_frame.spatial_id  = header->spatial_id;
>               s->cur_frame.temporal_id = header->temporal_id;
>   
> +            s->cur_frame.spatial_id  = header->spatial_id;
> +            s->cur_frame.temporal_id = header->temporal_id;
> +
>               if (avctx->hwaccel) {
>                   ret = avctx->hwaccel->start_frame(avctx, unit->data,
>                                                     unit->data_size);
> @@ -979,12 +992,28 @@ static void av1_decode_flush(AVCodecContext *avctx)
>           av1_frame_unref(avctx, &s->ref[i]);
>   
>       av1_frame_unref(avctx, &s->cur_frame);
> +    s->operating_point_idc = 0;
>       s->raw_frame_header = NULL;
>       s->raw_seq = NULL;
>   
>       ff_cbs_flush(s->cbc);
>   }
>   
> +#define OFFSET(x) offsetof(AV1DecContext, x)
> +#define VD AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_DECODING_PARAM
> +static const AVOption av1_options[] = {
> +    { "operating_point",  "Select an operating point of the scalable bitstream",
> +                          OFFSET(operating_point), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, AV1_MAX_OPERATING_POINTS - 1, VD },
> +    { NULL }
> +};
> +
> +static const AVClass av1_class = {
> +    .class_name = "AV1 decoder",
> +    .item_name  = av_default_item_name,
> +    .option     = av1_options,
> +    .version    = LIBAVUTIL_VERSION_INT,
> +};
> +
>   AVCodec ff_av1_decoder = {
>       .name                  = "av1",
>       .long_name             = NULL_IF_CONFIG_SMALL("Alliance for Open Media AV1"),
> @@ -1000,6 +1029,7 @@ AVCodec ff_av1_decoder = {
>                                FF_CODEC_CAP_SETS_PKT_DTS,
>       .flush                 = av1_decode_flush,
>       .profiles              = NULL_IF_CONFIG_SMALL(ff_av1_profiles),
> +    .priv_class            = &av1_class,
>       .hw_configs            = (const AVCodecHWConfigInternal * []) {
>   #if CONFIG_AV1_DXVA2_HWACCEL
>           HWACCEL_DXVA2(av1),
> diff --git a/libavcodec/av1dec.h b/libavcodec/av1dec.h
> index 4b218f64bb..70414c9ca3 100644
> --- a/libavcodec/av1dec.h
> +++ b/libavcodec/av1dec.h
> @@ -74,9 +74,13 @@ typedef struct AV1DecContext {
>       uint16_t tg_start;
>       uint16_t tg_end;
>   
> +    int operating_point_idc;
> +
>       AV1Frame ref[AV1_NUM_REF_FRAMES];
>       AV1Frame cur_frame;
>   
> +    // AVOptions
> +    int operating_point;
>   } AV1DecContext;
>   
>   #endif /* AVCODEC_AV1DEC_H */
> 

- Mark