[FFmpeg-devel] [PATCH v2 1/3] avcodec/avs3_parser: set has_b_frames properly

["zhilizhao(赵志立)"]

> On May 13, 2022, at 6:12 PM, Zhao Zhili <quinkblack at foxmail.com> wrote:
> 
> has_b_frames should be output_reorder_delay field in AVS3 sequence
> header and larger than 1. The parser implementation doesn't parse
> that field. Decoder can set has_b_frames properly, so use FFMAX
> here to avoid resetting has_b_frames from output_reorder_delay to 1.
> ---
> libavcodec/avs3_parser.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/libavcodec/avs3_parser.c b/libavcodec/avs3_parser.c
> index d04d96a03a..a9fd879e9d 100644
> --- a/libavcodec/avs3_parser.c
> +++ b/libavcodec/avs3_parser.c
> @@ -71,7 +71,7 @@ static void parse_avs3_nal_units(AVCodecParserContext *s, const uint8_t *buf,
>     if (buf[0] == 0x0 && buf[1] == 0x0 && buf[2] == 0x1) {
>         if (buf[3] == AVS3_SEQ_START_CODE) {
>             GetBitContext gb;
> -            int profile, ratecode;
> +            int profile, ratecode, low_delay;
> 
>             init_get_bits8(&gb, buf + 4, buf_size - 4);
> 
> @@ -114,7 +114,8 @@ static void parse_avs3_nal_units(AVCodecParserContext *s, const uint8_t *buf,
>             //            bitrate_high(12)
>             skip_bits(&gb, 32);
> 
> -            avctx->has_b_frames = !get_bits(&gb, 1);
> +            low_delay = get_bits(&gb, 1);
> +            avctx->has_b_frames = FFMAX(avctx->has_b_frames, !low_delay);
> 
>             avctx->framerate.num = avctx->time_base.den = ff_avs3_frame_rate_tab[ratecode].num;
>             avctx->framerate.den = avctx->time_base.num = ff_avs3_frame_rate_tab[ratecode].den;
> -- 
> 2.35.3
> 

Will apply this patchset tomorrow unless there are objections.