[FFmpeg-devel] [PATCHv6 4/4] libavcodec: v4l2: add support for v4l2 mem2mem codecs

Jorge Ramirez jorge.ramirez-ortiz at linaro.org
Sun Aug 27 22:09:29 EEST 2017


On 08/25/2017 05:35 PM, wm4 wrote:
>> +static int buffer_ops_v4l2buf_to_avframe(AVFrame *frame, V4L2Buffer *avbuf)
>> +{
>> +    int i, ret;
>> +
>> +    av_frame_unref(frame);
>> +
>> +    /* 1. get references to the actual data */
>> +    for (i = 0; i < avbuf->num_planes; i++) {
>> +        ret = avbuf->ops.buf_to_bufref(avbuf, i, &frame->buf[i]);
>> +        if (ret)
>> +            return ret;
>> +
>> +        frame->linesize[i] = avbuf->bytesperline[i];
>> +        frame->data[i] = frame->buf[i]->data;
>> +    }
>> +
>> +    /* 1.1 fixup special cases */
>> +    switch (avbuf->context->av_pix_fmt) {
>> +    case AV_PIX_FMT_NV12:
>> +        if (avbuf->num_planes > 1)
>> +            break;
>> +        frame->linesize[1] = avbuf->bytesperline[0];
>> +        frame->data[1] = frame->buf[0]->data + avbuf->bytesperline[0] * avbuf->context->format.fmt.pix_mp.height;
>> +        break;
>> +    default:
>> +        break;
>> +    }
>> +
>> +    /* 2. get frame information */
>> +    frame->key_frame = !!(avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME);
>> +    frame->format = avbuf->context->av_pix_fmt;
>> +
>> +    /* these values are updated also during re-init in process_video_event */
>> +    frame->height = avbuf->context->height;
>> +    frame->width = avbuf->context->width;
>> +    frame->pts = get_pts(avbuf);
>> +
>> +    /* 3. report errors upstream */
>> +    if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
>> +        av_log(avbuf->context->log_ctx, AV_LOG_ERROR, "%s: driver decode error\n", avbuf->context->name);
>> +        frame->decode_error_flags |= FF_DECODE_ERROR_INVALID_BITSTREAM;
>> +    }
>> +
>> +    return 0;
>> +}
> This function seems to lack setting typically required metadata like
> colorspace.
>

ok I will retrieve the colorspace from the v4l2 format structure and set 
it in the frame.
is there anything else I am missing?




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