Specifies color components (channels).

Values:

IG_COLOR_COMP_ALL	All components.
IG_COLOR_COMP_R	R component of RGB color space.
IG_COLOR_COMP_G	G component of RGB color space.
IG_COLOR_COMP_B	B component of RGB color space.
IG_COLOR_COMP_RGB	R, G, B components of RGB color space.
IG_COLOR_COMP_I	I component of indexed RGB color space.
IG_COLOR_COMP_C	C component of CMYK color space.
IG_COLOR_COMP_M	M component of CMYK color space.
IG_COLOR_COMP_Y	Y component of CMYK color space.
IG_COLOR_COMP_K	K component of CMYK color space.
IG_COLOR_COMP_CMYK	C, M, Y, K components of CMYK color space.
IG_COLOR_COMP_YUV_Y	Y component of YUV color space.
IG_COLOR_COMP_YUV_U	U component of YUV color space.
IG_COLOR_COMP_YUV_V	V component of YUV color space.
IG_COLOR_COMP_YUV	Y, U, V components of YUV color space.
IG_COLOR_COMP_LAB_L	L component of LAB color space.
IG_COLOR_COMP_LAB_A	A component of LAB color space.
IG_COLOR_COMP_LAB_B	B component of LAB color space.
IG_COLOR_COMP_LAB	L, A, B components of LAB color space.
IG_COLOR_COMP_IHS_I	I component of IHS color space.
IG_COLOR_COMP_IHS_H	H component of IHS color space.
IG_COLOR_COMP_IHS_S	S component of IHS color space.
IG_COLOR_COMP_IHS	I, H, S components of IHS color space.
IG_COLOR_COMP_HLS_H	H component of HLS color space.
IG_COLOR_COMP_HLS_L	L component of HLS color space.
IG_COLOR_COMP_HLS_S	S component of HLS color space.
IG_COLOR_COMP_HLS	H, L, S component of HLS color space.
IG_COLOR_COMP_HSL_H	This value has been deprecated and will be removed from the public API in a future release. Please use IG_COLOR_COMP_HLS_H instead.
IG_COLOR_COMP_HSL_S	This value has been deprecated and will be removed from the public API in a future release. Please use IG_COLOR_COMP_HLS_S instead.
IG_COLOR_COMP_HSL_L	This value has been deprecated and will be removed from the public API in a future release. Please use IG_COLOR_COMP_HLS_L instead.
IG_COLOR_COMP_HSL	This value has been deprecated and will be removed from the public API in a future release. Please use IG_COLOR_COMP_HLS instead.