![]() ![]() The cylindrical coordinates C* (chroma, relative saturation) and h° (hue angle, angle of the hue in the color wheel) are specified. This can be seen when the saturation settings are altered - it is quite easy to notice the difference in perceptual lightness despite the "V" or "L" setting being fixed.įor uniform color spaces that already have a lightness component, the transformation only involves rearranging the two chroma values into colorfulness (C) and hue (h).ĬIELCh ab and CIELCh uv are cylindrical transformations of the CIELAB and CIELUV color spaces, respectively. The issue with both HSV and HSL is that these approaches do not effectively separate colour into their three value components according to human perception of color. Shining a dim light on a red object causes the object to appear darker and less bright. shining a bright white light on a red object causes the object to still appear red, just brighter and more intense. The difference is that a perfectly light color in HSL is pure white but a perfectly bright color in HSV is analogous to shining a white light on a colored object. ![]() ![]() HSL (hue, saturation, lightness or luminance), also known as HSI (hue, saturation, intensity) or HSD (hue, saturation, darkness), is quite similar to HSV, with "lightness" replacing "brightness". ![]() HSV (hue, saturation, value), also known as HSB (hue, saturation, brightness), is often used by artists because it is often more natural to think about a color in terms of hue and saturation than in terms of additive or subtractive color components. HSV and HSL are transformations of Cartesian RGB primaries (usually sRGB), and their components and colorimetry are relative to the colorspace from which they are derived. ICtCp is used similarly to YCC in video compression, but is more appropriately described as a high dynamic range uniform color space. It results in faster computation, lossless conversion, and apparently better decorrelation. YCoCg is a version of YCbCr with extremely simple coefficients. In YCC, separating also has the added benefit of removing most of the correlation between the input channels, therefore providing better compression. YUV is originally used in video: as human eyes have less resolution in its color perception, it is more economic to put more of the bandwidth in encoding Luma. As the input RGB values are gamma-corrected, such a separation does not truly produce lightness and two chroma signals, but a "luma" signal and two " chrominance" signals instead. The analogue YUV and digital YCbCr refer to a variety of linear methods to try to separate lightness from chroma signals in an RGB input using linear combination.
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