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

[Andreas Rheinhardt]

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?
> 

Not in case of SMV. The smv code keeps a reference and reuses it. See
smv_process_frame.

>>
>> 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];