diff options
Diffstat (limited to 'src/libcamera/color_space.cpp')
| -rw-r--r-- | src/libcamera/color_space.cpp | 39 |
1 files changed, 23 insertions, 16 deletions
diff --git a/src/libcamera/color_space.cpp b/src/libcamera/color_space.cpp index caf39760..f0d6109a 100644 --- a/src/libcamera/color_space.cpp +++ b/src/libcamera/color_space.cpp @@ -29,21 +29,28 @@ namespace libcamera { * (sometimes also referred to as the quantisation) of the color space. * * Certain combinations of these fields form well-known standard color - * spaces such as "JPEG" or "REC709". + * spaces such as "sRGB" or "Rec709". * * In the strictest sense a "color space" formally only refers to the * color primaries and white point. Here, however, the ColorSpace class * adopts the common broader usage that includes the transfer function, * Y'CbCr encoding method and quantisation. * - * For more information on the specific color spaces described here, please - * see: + * More information on color spaces is available in the V4L2 documentation, see + * in particular * * - <a href="https://www.kernel.org/doc/html/latest/userspace-api/media/v4l/colorspaces-details.html#col-srgb">sRGB</a> * - <a href="https://www.kernel.org/doc/html/latest/userspace-api/media/v4l/colorspaces-details.html#col-jpeg">JPEG</a> * - <a href="https://www.kernel.org/doc/html/latest/userspace-api/media/v4l/colorspaces-details.html#col-smpte-170m">SMPTE 170M</a> * - <a href="https://www.kernel.org/doc/html/latest/userspace-api/media/v4l/colorspaces-details.html#col-rec709">Rec.709</a> * - <a href="https://www.kernel.org/doc/html/latest/userspace-api/media/v4l/colorspaces-details.html#col-bt2020">Rec.2020</a> + * + * Note that there is no guarantee of a 1:1 mapping between color space names + * and definitions in libcamera and V4L2. A notable difference is that the sYCC + * libcamera color space is called JPEG in V4L2 due to historical reasons. + * + * \todo Define the color space fully in the libcamera API to avoid referencing + * V4L2 */ /** @@ -121,8 +128,8 @@ namespace libcamera { * \brief Assemble and return a readable string representation of the * ColorSpace * - * If the color space matches a standard ColorSpace (such as ColorSpace::Jpeg) - * then the short name of the color space ("JPEG") is returned. Otherwise + * If the color space matches a standard ColorSpace (such as ColorSpace::Sycc) + * then the short name of the color space ("sYCC") is returned. Otherwise * the four constituent parts of the ColorSpace are assembled into a longer * string. * @@ -134,8 +141,8 @@ std::string ColorSpace::toString() const static const std::array<std::pair<ColorSpace, const char *>, 6> colorSpaceNames = { { { ColorSpace::Raw, "RAW" }, - { ColorSpace::Jpeg, "JPEG" }, { ColorSpace::Srgb, "sRGB" }, + { ColorSpace::Sycc, "sYCC" }, { ColorSpace::Smpte170m, "SMPTE170M" }, { ColorSpace::Rec709, "Rec709" }, { ColorSpace::Rec2020, "Rec2020" }, @@ -243,27 +250,27 @@ const ColorSpace ColorSpace::Raw = { }; /** - * \brief A constant representing the JPEG color space used for - * encoding JPEG images + * \brief A constant representing the sRGB color space + * + * This is identical to the sYCC color space except that the Y'CbCr + * range is limited rather than full. */ -const ColorSpace ColorSpace::Jpeg = { +const ColorSpace ColorSpace::Srgb = { Primaries::Rec709, TransferFunction::Srgb, YcbcrEncoding::Rec601, - Range::Full + Range::Limited }; /** - * \brief A constant representing the sRGB color space - * - * This is identical to the JPEG color space except that the Y'CbCr - * range is limited rather than full. + * \brief A constant representing the sYCC color space, typically used for + * encoding JPEG images */ -const ColorSpace ColorSpace::Srgb = { +const ColorSpace ColorSpace::Sycc = { Primaries::Rec709, TransferFunction::Srgb, YcbcrEncoding::Rec601, - Range::Limited + Range::Full }; /** |