[FFmpeg-devel] [PATCH 1/2] avcodec/jpeg2000dec: Set sample aspect ratio before getting buffer

[Andreas Rheinhardt]

Tomas Härdin:
> fre 2022-09-23 klockan 17:40 +0200 skrev Andreas Rheinhardt:
>> That way the SAR will be automatically set on the AVFrame.
>>
>> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
>> ---
>> If I am not mistaken, then the earlier code would set the sar
>> with a delay of one frame on the returned frames in case
>> there is a sar change mid-stream. But I don't have a sample
>> for this.
>>
>>  libavcodec/jpeg2000dec.c | 7 ++++---
>>  1 file changed, 4 insertions(+), 3 deletions(-)
>>
>> diff --git a/libavcodec/jpeg2000dec.c b/libavcodec/jpeg2000dec.c
>> index 7d9661f29f..c3f2a7aa03 100644
>> --- a/libavcodec/jpeg2000dec.c
>> +++ b/libavcodec/jpeg2000dec.c
>> @@ -2519,6 +2519,10 @@ static int
>> jpeg2000_decode_frame(AVCodecContext *avctx, AVFrame *picture,
>>      if (ret = jpeg2000_read_main_headers(s))
>>          goto end;
>>  
>> +    if (s->sar.num && s->sar.den)
>> +        avctx->sample_aspect_ratio = s->sar;
>> +    s->sar.num = s->sar.den = 0;
>> +
>>      /* get picture buffer */
>>      if ((ret = ff_thread_get_buffer(avctx, picture, 0)) < 0)
>>          goto end;
>> @@ -2547,9 +2551,6 @@ static int jpeg2000_decode_frame(AVCodecContext
>> *avctx, AVFrame *picture,
>>  
>>      if (s->avctx->pix_fmt == AV_PIX_FMT_PAL8)
>>          memcpy(picture->data[1], s->palette, 256 *
>> sizeof(uint32_t));
>> -    if (s->sar.num && s->sar.den)
>> -        avctx->sample_aspect_ratio = s->sar;
>> -    s->sar.num = s->sar.den = 0;
> 
> I suspect not doing this is what caused my simple hack to not work when
> ff_thread_get_buffer() was skipped. Looks OK, passes FATE.
> 

FYI: Patch two passes FATE even without patch one. In what way did your
simple hack not work when ff_thread_get_buffer() is skipped?

- Andreas