[FFmpeg-devel] [PATCH 07/29] lavc: add a decoder option for configuring side data preference

James Almer jamrial at gmail.com
Tue Mar 5 14:30:58 EET 2024


On 3/4/2024 10:06 AM, Anton Khirnov wrote:
> This and the following commits fix #10857
> ---
>   doc/APIchanges             |  3 +++
>   libavcodec/avcodec.h       | 20 ++++++++++++++++++++
>   libavcodec/decode.c        | 36 ++++++++++++++++++++++++++++++++++++
>   libavcodec/options_table.h | 13 +++++++++++++
>   4 files changed, 72 insertions(+)
> 
> diff --git a/doc/APIchanges b/doc/APIchanges
> index 3209614ed6..5d8585d8ba 100644
> --- a/doc/APIchanges
> +++ b/doc/APIchanges
> @@ -2,6 +2,9 @@ The last version increases of all libraries were on 2023-02-09
>   
>   API changes, most recent first:
>   
> +2024-02-xx - xxxxxxxxxx - lavc 60.xx.100 - avcodec.h
> +  Add AVCodecContext.[nb_]side_data_prefer_global.
> +
>   2024-02-xx - xxxxxxxxxx - lavu 58.xx.100 - opt.h
>     Add AV_OPT_TYPE_FLAG_ARRAY and AVOptionArrayDef.
>   
> diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
> index 43859251cc..307a3e99db 100644
> --- a/libavcodec/avcodec.h
> +++ b/libavcodec/avcodec.h
> @@ -2120,6 +2120,26 @@ typedef struct AVCodecContext {
>        *   an error.
>        */
>       int64_t frame_num;
> +
> +    /**
> +     * Decoding only. May be set by the caller before avcodec_open2() to an
> +     * av_malloc()'ed array (or via AVOptions). Owned and freed by the decoder
> +     * afterwards.
> +     *
> +     * By default, when some side data type is present both in global
> +     * user-supplied coded_side_data and inside the coded bitstream, avcodec
> +     * will propagate the latter to the decoded frame.
> +     *
> +     * This array contains a list of AVPacketSideDataType for which this
> +     * preference should be switched, i.e. avcodec will prefer global side data
> +     * over those in stored in the bytestream. It may also contain a single -1,
> +     * in which case the preference is switched for all side data types.
> +     */
> +    int        *side_data_prefer_global;
> +    /**
> +     * Number of entries in side_data_prefer_global.
> +     */
> +    unsigned nb_side_data_prefer_global;
>   } AVCodecContext;
>   
>   /**
> diff --git a/libavcodec/decode.c b/libavcodec/decode.c
> index 7c67b18bc4..5c80ef9cd0 100644
> --- a/libavcodec/decode.c
> +++ b/libavcodec/decode.c
> @@ -60,6 +60,12 @@ typedef struct DecodeContext {
>        * The caller has submitted a NULL packet on input.
>        */
>       int draining_started;
> +
> +    /**
> +     * Bitmask indicating for which side data types we prefer global
> +     * side data over per-packet.
> +     */
> +    uint64_t side_data_pref_mask;
>   } DecodeContext;
>   
>   static DecodeContext *decode_ctx(AVCodecInternal *avci)
> @@ -1744,6 +1750,7 @@ int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
>   int ff_decode_preinit(AVCodecContext *avctx)
>   {
>       AVCodecInternal *avci = avctx->internal;
> +    DecodeContext     *dc = decode_ctx(avci);
>       int ret = 0;
>   
>       /* if the decoder init function was already called previously,
> @@ -1804,6 +1811,35 @@ int ff_decode_preinit(AVCodecContext *avctx)
>           avctx->export_side_data |= AV_CODEC_EXPORT_DATA_MVS;
>       }
>   
> +    if (avctx->nb_side_data_prefer_global == 1 &&
> +        avctx->side_data_prefer_global[0] == -1)
> +        dc->side_data_pref_mask = ~0ULL;
> +    else {
> +        for (unsigned i = 0; i < avctx->nb_side_data_prefer_global; i++) {
> +            int val = avctx->side_data_prefer_global[i];
> +
> +            if (val < 0 || val >= AV_PKT_DATA_NB) {
> +                av_log(avctx, AV_LOG_ERROR, "Invalid side data type: %d\n", val);
> +                return AVERROR(EINVAL);
> +            }
> +
> +            for (unsigned j = 0; j < FF_ARRAY_ELEMS(sd_global_map); j++) {
> +                if (sd_global_map[j].packet == val) {
> +                    val = sd_global_map[j].frame;
> +
> +                    // this code will need to be changed when we have more than
> +                    // 64 frame side data types
> +                    if (val >= 64) {
> +                        av_log(avctx, AV_LOG_ERROR, "Side data type too big\n");
> +                        return AVERROR_BUG;
> +                    }
> +
> +                    dc->side_data_pref_mask |= 1ULL << val;
> +                }
> +            }
> +        }
> +    }
> +
>       avci->in_pkt         = av_packet_alloc();
>       avci->last_pkt_props = av_packet_alloc();
>       if (!avci->in_pkt || !avci->last_pkt_props)
> diff --git a/libavcodec/options_table.h b/libavcodec/options_table.h
> index ac32d8928a..3ff03d1cf0 100644
> --- a/libavcodec/options_table.h
> +++ b/libavcodec/options_table.h
> @@ -42,6 +42,8 @@
>   #define D AV_OPT_FLAG_DECODING_PARAM
>   #define CC AV_OPT_FLAG_CHILD_CONSTS
>   
> +#define AR AV_OPT_TYPE_FLAG_ARRAY
> +
>   #define AV_CODEC_DEFAULT_BITRATE 200*1000
>   
>   static const AVOption avcodec_options[] = {
> @@ -405,6 +407,17 @@ static const AVOption avcodec_options[] = {
>   {"unsafe_output", "allow potentially unsafe hwaccel frame output that might require special care to process successfully", 0, AV_OPT_TYPE_CONST, {.i64 = AV_HWACCEL_FLAG_UNSAFE_OUTPUT }, INT_MIN, INT_MAX, V | D, .unit = "hwaccel_flags"},
>   {"extra_hw_frames", "Number of extra hardware frames to allocate for the user", OFFSET(extra_hw_frames), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, V|D },
>   {"discard_damaged_percentage", "Percentage of damaged samples to discard a frame", OFFSET(discard_damaged_percentage), AV_OPT_TYPE_INT, {.i64 = 95 }, 0, 100, V|D },
> +{"side_data_prefer_global", "Comma-separated list of side data types for which global headers are preferred over frame-level data",
> +    OFFSET(side_data_prefer_global), AV_OPT_TYPE_INT | AR, .min = -1, .max = INT_MAX, .flags = V|A|S|D, .unit = "side_data_pkt" },
> +    {"replaygain",                  .default_val.i64 = AV_PKT_DATA_REPLAYGAIN,                  .type = AV_OPT_TYPE_CONST, .flags = A|D, .unit = "side_data_pkt" },
> +    {"displaymatrix",               .default_val.i64 = AV_PKT_DATA_DISPLAYMATRIX,               .type = AV_OPT_TYPE_CONST, .flags = A|D, .unit = "side_data_pkt" },
> +    {"spherical",                   .default_val.i64 = AV_PKT_DATA_SPHERICAL,                   .type = AV_OPT_TYPE_CONST, .flags = A|D, .unit = "side_data_pkt" },
> +    {"stereo3d",                    .default_val.i64 = AV_PKT_DATA_STEREO3D,                    .type = AV_OPT_TYPE_CONST, .flags = A|D, .unit = "side_data_pkt" },
> +    {"audio_service_type",          .default_val.i64 = AV_PKT_DATA_AUDIO_SERVICE_TYPE,          .type = AV_OPT_TYPE_CONST, .flags = A|D, .unit = "side_data_pkt" },
> +    {"mastering_display_metadata",  .default_val.i64 = AV_PKT_DATA_MASTERING_DISPLAY_METADATA,  .type = AV_OPT_TYPE_CONST, .flags = A|D, .unit = "side_data_pkt" },
> +    {"content_light_level",         .default_val.i64 = AV_PKT_DATA_CONTENT_LIGHT_LEVEL,         .type = AV_OPT_TYPE_CONST, .flags = A|D, .unit = "side_data_pkt" },
> +    {"icc_profile",                 .default_val.i64 = AV_PKT_DATA_ICC_PROFILE,                 .type = AV_OPT_TYPE_CONST, .flags = A|D, .unit = "side_data_pkt" },

> +    {"dynamic_hdr10_plus",          .default_val.i64 = AV_PKT_DATA_DYNAMIC_HDR10_PLUS,          .type = AV_OPT_TYPE_CONST, .flags = A|D, .unit = "side_data_pkt" },

This one packet/frame level only, not global. Is this option meant to 
also choose which one of those to use?

>   {NULL},
>   };
>   


More information about the ffmpeg-devel mailing list