[FFmpeg-devel] [PATCH] lavc/vvc: AVERROR_PATCHWELCOME for subpictures

[James Almer]

On 3/11/2024 9:49 PM, Michael Niedermayer wrote:
> On Mon, Mar 11, 2024 at 06:53:31PM +0000, Frank Plowman wrote:
>> VVC's subpictures feature is not yet implemented in the native decoder.
>> Throw an AVERROR_PATCHWELCOME when trying to decode a bitstream using
>> the feature.  Fixes crashes when trying to decode bitstreams which
>> use the feature.
>>
>> Signed-off-by: Frank Plowman <post at frankplowman.com>
>> ---
>>   libavcodec/vvc/vvc_ps.c | 15 +++++++++++++++
>>   1 file changed, 15 insertions(+)
> 
> This breaks fate-vvc-conformance-SUBPIC_A_3
> 
> make fate-vvc-conformance-SUBPIC_A_3
> TEST    vvc-conformance-SUBPIC_A_3
> --- ./tests/ref/fate/vvc-conformance-SUBPIC_A_3	2024-03-05 02:37:36.235300141 +0100
> +++ tests/data/fate/vvc-conformance-SUBPIC_A_3	2024-03-12 01:47:27.301593567 +0100
> @@ -1,9 +0,0 @@
> -#tb 0: 1/25
> -#media_type 0: video
> -#codec_id 0: rawvideo
> -#dimensions 0: 1920x1080
> -#sar 0: 0/1
> -0,          0,          0,        1,  6220800, 0xa419cfb6
> -0,          1,          1,        1,  6220800, 0xa419cfb6
> -0,          2,          2,        1,  6220800, 0xa419cfb6
> -0,          3,          3,        1,  6220800, 0xa419cfb6
> Test vvc-conformance-SUBPIC_A_3 failed. Look at tests/data/fate/vvc-conformance-SUBPIC_A_3.err for details.
> tests/Makefile:318: recipe for target 'fate-vvc-conformance-SUBPIC_A_3' failed
> make: *** [fate-vvc-conformance-SUBPIC_A_3] Error 69
> 
> thx

The sample appears to decode fine and doesn't crash, although all four 
frames are exactly the same (I don't know is that's intended).
Maybe the crashes can be fixed in some other form? And abort only if 
FF_COMPLIANCE_STRICT is requested.