[FFmpeg-devel] [PATCH 2/5] avcodec/mjpegdec: Don't create unnecessary AVFrame reference

[James Almer]

On 4/14/2022 12:57 PM, Andreas Rheinhardt wrote:
> MJPEG is an intra-codec, so it makes no sense to keep the reference.
> It is basically unused lateron anyway.

Wouldn't this mean you can remove the AV_GET_BUFFER_FLAG_REF flag from 
the ff_get_buffer() call?

> 
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> ---
>   libavcodec/mjpegdec.c | 45 +++++++++++++++++++++----------------------
>   1 file changed, 22 insertions(+), 23 deletions(-)
> 
> diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c
> index 0e76bf4c26..939dedce33 100644
> --- a/libavcodec/mjpegdec.c
> +++ b/libavcodec/mjpegdec.c
> @@ -2589,8 +2589,7 @@ eoi_parser:
>   
>                   av_freep(&s->hwaccel_picture_private);
>               }
> -            if ((ret = av_frame_ref(frame, s->picture_ptr)) < 0)
> -                return ret;
> +            av_frame_move_ref(frame, s->picture_ptr);
>               s->got_picture = 0;
>   
>               frame->pkt_dts = s->pkt->dts;
> @@ -2675,9 +2674,9 @@ the_end:
>           if (ret)
>               return ret;
>   
> -        av_assert0(s->nb_components == av_pix_fmt_count_planes(s->picture_ptr->format));
> +        av_assert0(s->nb_components == av_pix_fmt_count_planes(frame->format));
>           for (p = 0; p<s->nb_components; p++) {
> -            uint8_t *line = s->picture_ptr->data[p];
> +            uint8_t *line = frame->data[p];
>               int w = s->width;
>               int h = s->height;
>               if (!s->upscale_h[p])
> @@ -2737,7 +2736,7 @@ the_end:
>           if (ret)
>               return ret;
>   
> -        av_assert0(s->nb_components == av_pix_fmt_count_planes(s->picture_ptr->format));
> +        av_assert0(s->nb_components == av_pix_fmt_count_planes(frame->format));
>           for (p = 0; p < s->nb_components; p++) {
>               uint8_t *dst;
>               int w = s->width;
> @@ -2748,10 +2747,10 @@ the_end:
>                   w = AV_CEIL_RSHIFT(w, hshift);
>                   h = AV_CEIL_RSHIFT(h, vshift);
>               }
> -            dst = &((uint8_t *)s->picture_ptr->data[p])[(h - 1) * s->linesize[p]];
> +            dst = &frame->data[p][(h - 1) * s->linesize[p]];
>               for (i = h - 1; i; i--) {
> -                uint8_t *src1 = &((uint8_t *)s->picture_ptr->data[p])[i * s->upscale_v[p] / (s->upscale_v[p] + 1) * s->linesize[p]];
> -                uint8_t *src2 = &((uint8_t *)s->picture_ptr->data[p])[(i + 1) * s->upscale_v[p] / (s->upscale_v[p] + 1) * s->linesize[p]];
> +                uint8_t *src1 = &frame->data[p][ i      * s->upscale_v[p] / (s->upscale_v[p] + 1) * s->linesize[p]];
> +                uint8_t *src2 = &frame->data[p][(i + 1) * s->upscale_v[p] / (s->upscale_v[p] + 1) * s->linesize[p]];
>                   if (s->upscale_v[p] != 2 && (src1 == src2 || i == h - 1)) {
>                       memcpy(dst, src1, w);
>                   } else {
> @@ -2768,36 +2767,36 @@ the_end:
>           if (ret)
>               return ret;
>   
> -        av_assert0(s->nb_components == av_pix_fmt_count_planes(s->picture_ptr->format));
> +        av_assert0(s->nb_components == av_pix_fmt_count_planes(frame->format));
>           for (index=0; index<s->nb_components; index++) {
> -            uint8_t *dst = s->picture_ptr->data[index];
> -            int w = s->picture_ptr->width;
> -            int h = s->picture_ptr->height;
> +            uint8_t *dst = frame->data[index];
> +            int w = frame->width;
> +            int h = frame->height;
>               if(index && index<3){
>                   w = AV_CEIL_RSHIFT(w, hshift);
>                   h = AV_CEIL_RSHIFT(h, vshift);
>               }
>               if(dst){
> -                uint8_t *dst2 = dst + s->picture_ptr->linesize[index]*(h-1);
> +                uint8_t *dst2 = dst + frame->linesize[index]*(h-1);
>                   for (i=0; i<h/2; i++) {
>                       for (j=0; j<w; j++)
>                           FFSWAP(int, dst[j], dst2[j]);
> -                    dst  += s->picture_ptr->linesize[index];
> -                    dst2 -= s->picture_ptr->linesize[index];
> +                    dst  += frame->linesize[index];
> +                    dst2 -= frame->linesize[index];
>                   }
>               }
>           }
>       }
>       if (s->adobe_transform == 0 && s->avctx->pix_fmt == AV_PIX_FMT_GBRAP) {
> -        int w = s->picture_ptr->width;
> -        int h = s->picture_ptr->height;
> +        int w = frame->width;
> +        int h = frame->height;
>           av_assert0(s->nb_components == 4);
>           for (i=0; i<h; i++) {
>               int j;
>               uint8_t *dst[4];
>               for (index=0; index<4; index++) {
> -                dst[index] =   s->picture_ptr->data[index]
> -                             + s->picture_ptr->linesize[index]*i;
> +                dst[index] =   frame->data[index]
> +                             + frame->linesize[index]*i;
>               }
>               for (j=0; j<w; j++) {
>                   int k = dst[3][j];
> @@ -2812,15 +2811,15 @@ the_end:
>           }
>       }
>       if (s->adobe_transform == 2 && s->avctx->pix_fmt == AV_PIX_FMT_YUVA444P) {
> -        int w = s->picture_ptr->width;
> -        int h = s->picture_ptr->height;
> +        int w = frame->width;
> +        int h = frame->height;
>           av_assert0(s->nb_components == 4);
>           for (i=0; i<h; i++) {
>               int j;
>               uint8_t *dst[4];
>               for (index=0; index<4; index++) {
> -                dst[index] =   s->picture_ptr->data[index]
> -                             + s->picture_ptr->linesize[index]*i;
> +                dst[index] =   frame->data[index]
> +                             + frame->linesize[index]*i;
>               }
>               for (j=0; j<w; j++) {
>                   int k = dst[3][j];