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       gcp_pixel,  gcp_RGBAcolor,  gcp_YUVcolor,  gcp_CMYKcolor, gcp_HSVcolor,
       gcp_YCCcolor - LibGGIGCP color description


       #include <ggi/gcp.h>

       typedef ggi_pixel gcp_pixel;

       typedef ggi_color gcp_RGBAcolor;
       typedef struct { ggi_float y,u,v; } gcp_YUVcolor;
       typedef struct { uint16_t c,m,y,k; } gcp_CMYKcolor;
       typedef struct { ggi_float h,s,v; } gcp_HSVcolor;
       typedef struct { uint16_t y,c1,c2; } gcp_YCCcolor;


       Colors   are   described    generally    through    display-independent
       gcp_RGBAcolor,    gcp_YUVcolor,    gcp_CMYKcolor,    gcp_HSVcolor   and
       gcp_YCCcolor structures for the RGBA, YUV,  CMYK,  HSV  and  YCC  color

       gcp_pixels are display-dependent pixel values. They are used by all GCP
       operations for efficiency.  Use gcpMap*Color(3) to convert  gcp_*colors
       to gcp_pixels.


       gcp_RGBAcolor  represents  the  rgba  colorspace  and  is  the  same as

       gcp_YUVcolor represents the YUV colorspace. It consists of y, u and  v.
       They correspond to the luminance and chrominance components.

       gcp_CMYKcolor  represents  the  CMYK colorspace. It consists of c, m, y
       and k. They correspond to the cyan, magenta, yellow and black channels.

       gcp_HSVcolor  represents the HSV colorspace. It consists of h, s and v.
       They correspond to the hue, saturation and velocity.

       gcp_YCCcolor, better known as Kodak PhotoCD. It consists of y,  c1  and

       gcp_pixels format depends on the actual display and mode. For those who
       want to operate directly on pixel values, this format is  described  in
       the ggi_pixelformat(3) structure.


       Although  individual  pixels are kept into 32 bits gcp_pixel, arrays of
       pixels,  as  used  in  ggi[Get|Put]*  functions,   gcpPack*Colors   and
       gcpUnpack*Pixels,  are  stored  in  the  display  specific format, thus
       packed according to the actual pixel size.  This size is given  by  the
       GT_SIZE macro for graphtype or the size field of the ggi_pixelformat(3)

       The buffers provided to these functions must be big enough to store  or
       read  enough  pixels. Although it is safe to use 32 bits per pixel, the
       optimum size (in bits) can be calculated by multiplying the  number  of
       pixel by their size. Don’t forget to round up to a multiple of 8 to get
       the number of bytes.

       If you want to  access  such  buffers  directly,  do  not  use  pointer
       arithmetics with gcp_pixels.


       gcpMapRGBAColor(3),        gcpMapYUVColor(3),        gcpMapHSVColor(3),
       gcpMapCMYKColor(3), gcpMapYCCColor(3), ggi_pixelformat(3)