On 10/13/20 4:40 PM, Tomasz Figa wrote: > On Tue, Oct 13, 2020 at 11:03 AM Stanimir Varbanov > <stanimir.varbanov@xxxxxxxxxx> wrote: >> >> Hi, >> >> On 7/2/20 2:52 PM, Stanimir Varbanov wrote: >>> Hi, >>> >>> Once we have this event there is still open question how the client will >>> know the data buffer on which the new colorspace is valid/applied. >>> >>> The options could be: >>> * a new buffer flag and >>> * some information in the v4l2_event structure. >>> >>> Thoughts? >> >> Kindly ping. >> > > The event itself sounds good to me, but how do we know which buffer is > the first to have the new colorimetry? I think Hans have a very good idea to have width/height and colorspace specifiers in v4l2_ext_buffer [1]. [1] https://lkml.org/lkml/2020/9/9/531 > > Best regards, > Tomasz > >>> >>> On 7/2/20 1:00 PM, Stanimir Varbanov wrote: >>>> This event indicate that the source colorspace is changed >>>> during run-time. The client has to retrieve the new colorspace >>>> identifiers by getting the format (G_FMT). >>>> >>>> Signed-off-by: Stanimir Varbanov <stanimir.varbanov@xxxxxxxxxx> >>>> --- >>>> .../userspace-api/media/v4l/vidioc-dqevent.rst | 11 ++++++++++- >>>> .../userspace-api/media/videodev2.h.rst.exceptions | 1 + >>>> include/uapi/linux/videodev2.h | 1 + >>>> 3 files changed, 12 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/Documentation/userspace-api/media/v4l/vidioc-dqevent.rst b/Documentation/userspace-api/media/v4l/vidioc-dqevent.rst >>>> index a9a176d5256d..3f69c753db58 100644 >>>> --- a/Documentation/userspace-api/media/v4l/vidioc-dqevent.rst >>>> +++ b/Documentation/userspace-api/media/v4l/vidioc-dqevent.rst >>>> @@ -381,7 +381,16 @@ call. >>>> that many Video Capture devices are not able to recover from a temporary >>>> loss of signal and so restarting streaming I/O is required in order for >>>> the hardware to synchronize to the video signal. >>>> - >>>> + * - ``V4L2_EVENT_SRC_CH_COLORIMETRY`` >>>> + - 0x0002 >>>> + - This event gets triggered when a colorspace change is detected at >>>> + an input. By colorspace change here we include also changes in the >>>> + colorspace specifiers (transfer function, Y'CbCr encoding and >>>> + quantization). This event can come from an input or from video decoder. >>>> + Once the event has been send to the client the driver has to update >>>> + the colorspace specifiers internally so that they could be retrieved by >>>> + client. In that case queue re-negotiation is not needed as this change >>>> + only reflects on the interpretation of the data. >>>> >>>> Return Value >>>> ============ >>>> diff --git a/Documentation/userspace-api/media/videodev2.h.rst.exceptions b/Documentation/userspace-api/media/videodev2.h.rst.exceptions >>>> index ca05e4e126b2..54fc21af852d 100644 >>>> --- a/Documentation/userspace-api/media/videodev2.h.rst.exceptions >>>> +++ b/Documentation/userspace-api/media/videodev2.h.rst.exceptions >>>> @@ -492,6 +492,7 @@ replace define V4L2_EVENT_CTRL_CH_FLAGS ctrl-changes-flags >>>> replace define V4L2_EVENT_CTRL_CH_RANGE ctrl-changes-flags >>>> >>>> replace define V4L2_EVENT_SRC_CH_RESOLUTION src-changes-flags >>>> +replace define V4L2_EVENT_SRC_CH_COLORIMETRY src-changes-flags >>>> >>>> replace define V4L2_EVENT_MD_FL_HAVE_FRAME_SEQ :c:type:`v4l2_event_motion_det` >>>> >>>> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h >>>> index 303805438814..b5838bc4e3a3 100644 >>>> --- a/include/uapi/linux/videodev2.h >>>> +++ b/include/uapi/linux/videodev2.h >>>> @@ -2351,6 +2351,7 @@ struct v4l2_event_frame_sync { >>>> }; >>>> >>>> #define V4L2_EVENT_SRC_CH_RESOLUTION (1 << 0) >>>> +#define V4L2_EVENT_SRC_CH_COLORIMETRY (1 << 1) >>>> >>>> struct v4l2_event_src_change { >>>> __u32 changes; >>>> >>> >> >> -- >> regards, >> Stan -- regards, Stan
