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Inside Macintosh: Advanced Color Imaging Reference /

Chapter 3 - ColorSync Manager Reference for Applications and Device Drivers / Constants and Data Types

Defining Color Spaces

Abstract Color Space Constants

The CMBitmap data type (page 3-61) defines a bitmap for an image whose colors can be matched with the CWMatchBitmap function (page 3-120) or color-checked with the CWCheckBitmap function (page 3-123).

The space field of the CMBitmap type definition identifies the color space in which the colors of the bitmap image are specified. A color space is characterized by a number of components or dimensions, with each component carrying a numeric value. These values totaled comprise the color value. A color space also specifies the format in which the color value is stored. For bitmaps in which color values are packed, the space field of the CMBitmap data type holds a constant that defines the color space and the packing format.

For the CWMatchBitmap function to perform color matching successfully, the color space specified in the CMBitmap data type's space field must correspond to the color space specified in the profile's dataColorSpace field. The source bitmap and source profile values must match, and the destination bitmap and destination profile values must match. For the CWCheckBitMap function to perform color checking successfully, the source profile's dataColorSpace field value and the space field value of the source bitmap must specify the same color space. These functions will execute successfully as long as the color spaces are the same without regard for the packing format specified by the bitmap.

The following enumeration defines constants for abstract color spaces which, when combined with a packing format (page 3-21), can be used in the space field of the CMBitmap structure.

enum {
   cmNoSpace      = 0,
   cmRGBSpace     = 1,
   cmCMYKSpace    = 2,
   cmHSVSpace     = 3,
   cmHLSSpace     = 4,
   cmYXYSpace     = 5,
   cmXYZSpace     = 6,
   cmLUVSpace     = 7,
   cmLABSpace     = 8,
   cmReservedSpace1= 9,
   cmGraySpace    = 10,
   cmReservedSpace2= 11,
   cmGamutResultSpace= 12,
   cmNamedIndexedSpace= 16,
   cmMCFiveSpace  = 17,
   cmMCSixSpace   = 18,
   cmMCSevenSpace = 19,
   cmMCEightSpace = 20
};

Enumerator descriptions

cmNoSpace

The ColorSync Manager does not use this constant.

cmRGBSpace

An RGB color space composed of red, green, and blue components. A bitmap never uses this constant alone. Instead, this color space is always combined with a packing format describing the amount of storage per component.

cmCMYKSpace

A CMYK color space composed of cyan, magenta, yellow, and black. A bitmap never uses this constant alone. Instead, this color space is always combined with a packing format describing the amount of storage per component.

cmHSVSpace

An HSV color space composed of hue, saturation, and value components. A bitmap never uses this constant alone. Instead, this color space is always combined with a packing format describing the amount of storage per component.

cmHLSSpace

An HLS color space composed of hue, lightness, and saturation components. A bitmap never uses this constant alone. Instead, this color space is always combined with a packing format describing the amount of storage per component.

cmYXYSpace

A Yxy color space composed of Y, x, and y components. A bitmap never uses this constant alone. Instead, this color space is always combined with a packing format describing the amount of storage per component.

cmXYZSpace

An XYZ color space composed of X, Y, and Z components. A bitmap never uses this constant alone. Instead, this color space is always combined with a packing format describing the amount of storage per component.

cmLUVSpace

An L*u*v* color space composed of L*, u*, and v* components. A bitmap never uses this constant alone. Instead, this color space is always combined with a packing format describing the amount of storage per component.

cmLABSpace

An L*a*b* color space composed of L*, a*, b* components. A bitmap never uses this constant alone. Instead, this color space is always combined with a packing format describing the amount of storage per component.

cmReservedSpace1

This field is reserved for use by QuickDraw GX.

cmGraySpace

A luminance color space with a single component, gray.

cmReservedSpace2

This field is reserved for use by QuickDraw GX.

cmGamutResultSpace

A color space for the resulting bitmap pointed to by the resultBitMap field of the CWCheckBitMap function (page 3-123). A bitmap never uses this constant alone. Instead, it uses the constant cmGamutResult1Space, which combines cmGamutResultSpace with cmOneBitDirectPacking to define a bitmap that is 1 bit deep.

cmMCFiveSpace

A five-channel multichannel (HiFi) data color space.

cmMCSixSpace

A six-channel multichannel (HiFi) data color space.

cmMCSevenSpace

A seven-channel multichannel (HiFi) data color space.

cmMCEightSpace

An eight-channel multichannel (HiFi) data color space.