NekoCWD/libcamera
NekoCWD/libcamera
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages 7 Wiki Activity Actions

libcamera: colorspace: Rectify the ColorSpace::Srgb preset

Browse source 
Rectify the ColorSpace::Srgb to denote that it does not use
any Y'Cbcr encoding and uses full range.

The kernel on the other hand, recommends to use Rec601 as the encoding
for V4L2_COLORSPACE_SRGB. It is not very explicit but it can be
inferred that the kernel assumes V4L2_COLORSPACE_SRGB is a YUV-encoded
one. However, when the data is in RGB, no encoding is required (and
this is denoted by YcbcrEncoding::None in libcamera).

Hence, to be clear on the libcamera colorspace API, rectify the
ColorSpace::Srgb preset to use YcbcrEncoding::None and full range.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
This commit is contained in:
Umang Jain 2022-08-30 13:17:22 +05:30
parent e52729e7ec
commit d09c2bb127
2 changed files with 15 additions and 10 deletions
Download patch file Download diff file Expand all files Collapse all files

7
src/libcamera/v4l2_device.cpp
View file

@ -746,7 +746,11 @@ void V4L2Device::eventAvailable()
static const std::map<uint32_t, ColorSpace> v4l2ToColorSpace = {
{ V4L2_COLORSPACE_RAW, ColorSpace::Raw },
{ V4L2_COLORSPACE_SRGB, ColorSpace::Srgb },
{ V4L2_COLORSPACE_SRGB, {
ColorSpace::Primaries::Rec709,
ColorSpace::TransferFunction::Srgb,
ColorSpace::YcbcrEncoding::Rec601,
ColorSpace::Range::Limited } },
{ V4L2_COLORSPACE_JPEG, ColorSpace::Sycc },
{ V4L2_COLORSPACE_SMPTE170M, ColorSpace::Smpte170m },
{ V4L2_COLORSPACE_REC709, ColorSpace::Rec709 },
@ -772,7 +776,6 @@ static const std::map<uint32_t, ColorSpace::Range> v4l2ToRange = {
static const std::vector<std::pair<ColorSpace, v4l2_colorspace>> colorSpaceToV4l2 = {
{ ColorSpace::Raw, V4L2_COLORSPACE_RAW },
{ ColorSpace::Srgb, V4L2_COLORSPACE_SRGB },
{ ColorSpace::Sycc, V4L2_COLORSPACE_JPEG },
{ ColorSpace::Smpte170m, V4L2_COLORSPACE_SMPTE170M },
{ ColorSpace::Rec709, V4L2_COLORSPACE_REC709 },