[FFmpeg-devel] [PATCHv8] libavcodec: v4l2: add support for v4l2 mem2mem codecs

[Jorge Ramirez]

On 09/03/2017 04:56 PM, Jorge Ramirez wrote:
> On 09/03/2017 02:27 AM, Mark Thompson wrote:
>>> +    .long_name      = NULL_IF_CONFIG_SMALL("V4L2 mem2mem " LONGNAME " decoder wrapper"),\
>>> +    .type           = AVMEDIA_TYPE_VIDEO,\
>>> +    .id             = CODEC ,\
>>> +    .priv_data_size = sizeof(V4L2m2mContext),\
>>> +    .priv_class     = &v4l2_m2m_ ## NAME ## _dec_class,\
>>> +    .init           = v4l2m2m_decode_init,\
>>> +    .receive_frame  = v4l2m2m_receive_frame,\
>>> +    .close          = ff_v4l2m2m_codec_end,\
>>> +    .bsfs           = bsf_name, \
>>> +};
>>> +
>>> +M2MDEC(h264,  "H.264", AV_CODEC_ID_H264,       "h264_mp4toannexb");
>>> +M2MDEC(hevc,  "HEVC",  AV_CODEC_ID_HEVC,       "h264_mp4toannexb");
>> h264_mp4toannexb is for H.264, and will refuse to do anything with H.265:
>>
>> "[AVBSFContext @ 0x55f4d346c620] Codec 'hevc' (174) is not supported by the bitstream filter 'h264_mp4toannexb'. Supported codecs are: h264 (28)."
>>
>> (Was this decoder really tested as the commit message claims?)
>>
>
> yes it was a couple of versions ago though: without it, the decoded 
> frames could not be displayed using the dragon board 820c.
> however just tried again and got the error message that you mentioned;
> [...]
> [AVBSFContext @ 0xffff74000b90] Codec 'hevc' (174) is not supported by 
> the bitstream filter 'h264_mp4toannexb'. Supported codecs are: h264 (28)
> [AVBSFContext @ 0xffff74000b90] Codec 'hevc' (174) is not supported by 
> the bitstream filter 'h264_mp4toannexb'. Supported codecs are: h264 (28)
> [AVBSFContext @ 0xffff74000b90] Codec 'hevc' (174) is not supported by 
> the bitstream filter 'h264_mp4toannexb'. Supported codecs are: h264 (28)
> [AVBSFContext @ 0xffff74000b90] Codec 'hevc' (174) is not supported by 
> the bitstream filter 'h264_mp4toannexb'. Supported codecs are: h264 (28)
> [AVBSFContext @ 0xffff74000b90] Codec 'hevc' (174) is not supported by 
> the bitstream filter 'h264_mp4toannexb'. Supported codecs are: h264 (28)
>
> yeah now, after removing the h264_mp4toannexb from the decoder, I can 
> not play any HEVC videos on the db820c.....I'll then remove HEVC from 
> the list of supported decoders then. It is a pity.
>
>
>

actually I will just remove the filter from the hevc decoder 
instantiation in case some v4l2 codec (different from the one in the 
db820) can still benefit