Hi Adam, Thank you for the patch.
On Wed, Sep 02, 2020 at 04:06:17PM -0400, Adam Goode wrote: > The Color Matching Descriptor has been present in USB cameras since > the original version of UVC, but it has never been fully exposed > in Linux. > > This change informs V4L2 of all of the UVC colorspace parameters: > color primaries, transfer characteristics, and YCbCr encoding. > videodev2.h doesn't have values for all the possible UVC color settings, > so it is mapped as closely as possible. > > Signed-off-by: Adam Goode <[email protected]> > --- > > Changes in v3: > - Remove quantization changes completely. > > drivers/media/usb/uvc/uvc_driver.c | 64 ++++++++++++++++++++++++++++-- > drivers/media/usb/uvc/uvc_v4l2.c | 4 ++ > drivers/media/usb/uvc/uvcvideo.h | 4 +- > 3 files changed, 67 insertions(+), 5 deletions(-) > > diff --git a/drivers/media/usb/uvc/uvc_driver.c > b/drivers/media/usb/uvc/uvc_driver.c > index 431d86e1c94b..8682c7ad6949 100644 > --- a/drivers/media/usb/uvc/uvc_driver.c > +++ b/drivers/media/usb/uvc/uvc_driver.c > @@ -248,10 +248,10 @@ static struct uvc_format_desc *uvc_format_by_guid(const > u8 guid[16]) > return NULL; > } > > -static u32 uvc_colorspace(const u8 primaries) > +static enum v4l2_colorspace uvc_colorspace(const u8 primaries) > { > - static const u8 colorprimaries[] = { > - 0, > + static const enum v4l2_colorspace colorprimaries[] = { > + V4L2_COLORSPACE_DEFAULT, /* Unspecified */ > V4L2_COLORSPACE_SRGB, > V4L2_COLORSPACE_470_SYSTEM_M, > V4L2_COLORSPACE_470_SYSTEM_BG, > @@ -262,7 +262,61 @@ static u32 uvc_colorspace(const u8 primaries) > if (primaries < ARRAY_SIZE(colorprimaries)) > return colorprimaries[primaries]; > > - return 0; > + return V4L2_COLORSPACE_DEFAULT; /* Reserved */ > +} > + > +static enum v4l2_xfer_func uvc_xfer_func(const u8 transfer_characteristics) > +{ > + /* V4L2 currently does not currently have definitions for all A single "currently" should be enough :-) I'll fix this when applying. > + * possible values of UVC transfer characteristics. If > + * v4l2_xfer_func is extended with new values, the mapping > + * below should be updated. > + * > + * Substitutions are taken from the mapping given for > + * V4L2_XFER_FUNC_DEFAULT documented in videodev2.h. > + */ > + static const enum v4l2_xfer_func xfer_funcs[] = { > + V4L2_XFER_FUNC_DEFAULT, /* Unspecified */ > + V4L2_XFER_FUNC_709, > + V4L2_XFER_FUNC_709, /* Substitution for BT.470-2 M */ > + V4L2_XFER_FUNC_709, /* Substitution for BT.470-2 B, G */ > + V4L2_XFER_FUNC_709, /* Substitution for SMPTE 170M */ > + V4L2_XFER_FUNC_SMPTE240M, > + V4L2_XFER_FUNC_NONE, > + V4L2_XFER_FUNC_SRGB, > + }; > + > + if (transfer_characteristics < ARRAY_SIZE(xfer_funcs)) > + return xfer_funcs[transfer_characteristics]; > + > + return V4L2_XFER_FUNC_DEFAULT; /* Reserved */ > +} > + > +static enum v4l2_ycbcr_encoding uvc_ycbcr_enc(const u8 matrix_coefficients) > +{ > + /* V4L2 currently does not currently have definitions for all Same here. Reviewed-by: Laurent Pinchart <[email protected]> > + * possible values of UVC matrix coefficients. If > + * v4l2_ycbcr_encoding is extended with new values, the > + * mapping below should be updated. > + * > + * Substitutions are taken from the mapping given for > + * V4L2_YCBCR_ENC_DEFAULT documented in videodev2.h. > + * > + * FCC is assumed to be close enough to 601. > + */ > + static const enum v4l2_ycbcr_encoding ycbcr_encs[] = { > + V4L2_YCBCR_ENC_DEFAULT, /* Unspecified */ > + V4L2_YCBCR_ENC_709, > + V4L2_YCBCR_ENC_601, /* Substitution for FCC */ > + V4L2_YCBCR_ENC_601, /* Substitution for BT.470-2 B, G */ > + V4L2_YCBCR_ENC_601, > + V4L2_YCBCR_ENC_SMPTE240M, > + }; > + > + if (matrix_coefficients < ARRAY_SIZE(ycbcr_encs)) > + return ycbcr_encs[matrix_coefficients]; > + > + return V4L2_YCBCR_ENC_DEFAULT; /* Reserved */ > } > > /* Simplify a fraction using a simple continued fraction decomposition. The > @@ -704,6 +758,8 @@ static int uvc_parse_format(struct uvc_device *dev, > } > > format->colorspace = uvc_colorspace(buffer[3]); > + format->xfer_func = uvc_xfer_func(buffer[4]); > + format->ycbcr_enc = uvc_ycbcr_enc(buffer[5]); > > buflen -= buffer[0]; > buffer += buffer[0]; > diff --git a/drivers/media/usb/uvc/uvc_v4l2.c > b/drivers/media/usb/uvc/uvc_v4l2.c > index 0335e69b70ab..dee65e89d6c2 100644 > --- a/drivers/media/usb/uvc/uvc_v4l2.c > +++ b/drivers/media/usb/uvc/uvc_v4l2.c > @@ -253,6 +253,8 @@ static int uvc_v4l2_try_format(struct uvc_streaming > *stream, > fmt->fmt.pix.bytesperline = uvc_v4l2_get_bytesperline(format, frame); > fmt->fmt.pix.sizeimage = probe->dwMaxVideoFrameSize; > fmt->fmt.pix.colorspace = format->colorspace; > + fmt->fmt.pix.xfer_func = format->xfer_func; > + fmt->fmt.pix.ycbcr_enc = format->ycbcr_enc; > > if (uvc_format != NULL) > *uvc_format = format; > @@ -289,6 +291,8 @@ static int uvc_v4l2_get_format(struct uvc_streaming > *stream, > fmt->fmt.pix.bytesperline = uvc_v4l2_get_bytesperline(format, frame); > fmt->fmt.pix.sizeimage = stream->ctrl.dwMaxVideoFrameSize; > fmt->fmt.pix.colorspace = format->colorspace; > + fmt->fmt.pix.xfer_func = format->xfer_func; > + fmt->fmt.pix.ycbcr_enc = format->ycbcr_enc; > > done: > mutex_unlock(&stream->mutex); > diff --git a/drivers/media/usb/uvc/uvcvideo.h > b/drivers/media/usb/uvc/uvcvideo.h > index 6ab972c643e3..eb5f3ffc0222 100644 > --- a/drivers/media/usb/uvc/uvcvideo.h > +++ b/drivers/media/usb/uvc/uvcvideo.h > @@ -370,7 +370,9 @@ struct uvc_format { > u8 type; > u8 index; > u8 bpp; > - u8 colorspace; > + enum v4l2_colorspace colorspace; > + enum v4l2_xfer_func xfer_func; > + enum v4l2_ycbcr_encoding ycbcr_enc; > u32 fcc; > u32 flags; > -- Regards, Laurent Pinchart
