[FFmpeg-devel] [PATCH] avcodec/mpegvideo_enc: Initialize dct_unquantize_int(ra|er) only once

Andreas Rheinhardt andreas.rheinhardt at outlook.com
Sat Oct 29 19:47:00 EEST 2022


Andreas Rheinhardt:
> For encoders, mpeg_quant is an option of the MPEG-4 encoder
> and therefore constant. This implies that one can set
> the dct_unquantize_(intra|inter) function pointers during init.
> 
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> ---
>  libavcodec/mpegvideo_enc.c | 22 +++++++++++-----------
>  1 file changed, 11 insertions(+), 11 deletions(-)
> 
> diff --git a/libavcodec/mpegvideo_enc.c b/libavcodec/mpegvideo_enc.c
> index ce363a585d..0b709974a1 100644
> --- a/libavcodec/mpegvideo_enc.c
> +++ b/libavcodec/mpegvideo_enc.c
> @@ -880,6 +880,17 @@ av_cold int ff_mpv_encode_init(AVCodecContext *avctx)
>  
>      ff_dct_encode_init(s);
>  
> +    if (s->mpeg_quant || s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
> +        s->dct_unquantize_intra = s->dct_unquantize_mpeg2_intra;
> +        s->dct_unquantize_inter = s->dct_unquantize_mpeg2_inter;
> +    } else if (s->out_format == FMT_H263 || s->out_format == FMT_H261) {
> +        s->dct_unquantize_intra = s->dct_unquantize_h263_intra;
> +        s->dct_unquantize_inter = s->dct_unquantize_h263_inter;
> +    } else {
> +        s->dct_unquantize_intra = s->dct_unquantize_mpeg1_intra;
> +        s->dct_unquantize_inter = s->dct_unquantize_mpeg1_inter;
> +    }
> +
>      if ((CONFIG_H263P_ENCODER || CONFIG_RV20_ENCODER) && s->modified_quant)
>          s->chroma_qscale_table = ff_h263_chroma_qscale_table;
>  
> @@ -1723,17 +1734,6 @@ static int frame_start(MpegEncContext *s)
>          }
>      }
>  
> -    if (s->mpeg_quant || s->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
> -        s->dct_unquantize_intra = s->dct_unquantize_mpeg2_intra;
> -        s->dct_unquantize_inter = s->dct_unquantize_mpeg2_inter;
> -    } else if (s->out_format == FMT_H263 || s->out_format == FMT_H261) {
> -        s->dct_unquantize_intra = s->dct_unquantize_h263_intra;
> -        s->dct_unquantize_inter = s->dct_unquantize_h263_inter;
> -    } else {
> -        s->dct_unquantize_intra = s->dct_unquantize_mpeg1_intra;
> -        s->dct_unquantize_inter = s->dct_unquantize_mpeg1_inter;
> -    }
> -
>      if (s->dct_error_sum) {
>          av_assert2(s->noise_reduction && s->encoding);
>          update_noise_reduction(s);

Will apply this patch tomorrow unless there are objections.

- Andreas



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