[libcamera-devel] [PATCH v3] libcamera: v4l2: Set colorspace flags

[Laurent Pinchart]

Hi Umang,

Thank you for the patch.

On Fri, Aug 12, 2022 at 02:23:24PM +0530, Umang Jain via libcamera-devel wrote:
> The colorspace fields are read-only from an application point of view,
> both on video devices and on subdevs, unless the
> V4L2_PIX_FMT_FLAG_SET_CSC or V4L2_MBUS_FRAMEFMT_SET_CSC flags
> (respectively) are set when calling the S_FMT ioctl.
> 
> Signed-off-by: Umang Jain <umang.jain at ideasonboard.com>

Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

> ---
>  src/libcamera/v4l2_subdevice.cpp   |  8 +++++++-
>  src/libcamera/v4l2_videodevice.cpp | 14 ++++++++++++--
>  2 files changed, 19 insertions(+), 3 deletions(-)
> 
> diff --git a/src/libcamera/v4l2_subdevice.cpp b/src/libcamera/v4l2_subdevice.cpp
> index e5d20f2c..d8fd92e3 100644
> --- a/src/libcamera/v4l2_subdevice.cpp
> +++ b/src/libcamera/v4l2_subdevice.cpp
> @@ -526,7 +526,13 @@ int V4L2Subdevice::setFormat(unsigned int pad, V4L2SubdeviceFormat *format,
>  	subdevFmt.format.height = format->size.height;
>  	subdevFmt.format.code = format->mbus_code;
>  	subdevFmt.format.field = V4L2_FIELD_NONE;
> -	fromColorSpace(format->colorSpace, subdevFmt.format);
> +	if (format->colorSpace) {
> +		fromColorSpace(format->colorSpace, subdevFmt.format);
> +
> +		/* The CSC flag is only applicable to source pads. */
> +		if (entity_->pads()[pad]->flags() & MEDIA_PAD_FL_SOURCE)
> +			subdevFmt.format.flags |= V4L2_MBUS_FRAMEFMT_SET_CSC;
> +	}
>  
>  	int ret = ioctl(VIDIOC_SUBDEV_S_FMT, &subdevFmt);
>  	if (ret) {
> diff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp
> index b80ee1cd..5a2d0e5b 100644
> --- a/src/libcamera/v4l2_videodevice.cpp
> +++ b/src/libcamera/v4l2_videodevice.cpp
> @@ -953,7 +953,12 @@ int V4L2VideoDevice::trySetFormatMultiplane(V4L2DeviceFormat *format, bool set)
>  	pix->pixelformat = format->fourcc;
>  	pix->num_planes = format->planesCount;
>  	pix->field = V4L2_FIELD_NONE;
> -	fromColorSpace(format->colorSpace, *pix);
> +	if (format->colorSpace) {
> +		fromColorSpace(format->colorSpace, *pix);
> +
> +		if (caps_.isVideoCapture())
> +			pix->flags |= V4L2_PIX_FMT_FLAG_SET_CSC;
> +	}
>  
>  	ASSERT(pix->num_planes <= std::size(pix->plane_fmt));
>  
> @@ -1023,7 +1028,12 @@ int V4L2VideoDevice::trySetFormatSingleplane(V4L2DeviceFormat *format, bool set)
>  	pix->pixelformat = format->fourcc;
>  	pix->bytesperline = format->planes[0].bpl;
>  	pix->field = V4L2_FIELD_NONE;
> -	fromColorSpace(format->colorSpace, *pix);
> +	if (format->colorSpace) {
> +		fromColorSpace(format->colorSpace, *pix);
> +
> +		if (caps_.isVideoCapture())
> +			pix->flags |= V4L2_PIX_FMT_FLAG_SET_CSC;
> +	}
>  
>  	ret = ioctl(set ? VIDIOC_S_FMT : VIDIOC_TRY_FMT, &v4l2Format);
>  	if (ret) {

-- 
Regards,

Laurent Pinchart