HistogramColorPacket *GetColorHistogram( const Image *, unsigned long *colors, ExceptionInfo *);
Method GetColorHistogram returns an array of HistogramColorPacket structures which specify the number of times each unique color occurs in the image. The referenced colors parameter is updated with the number of unique colors in the image. The returned array should be deallocated by the user once it is no longer ndded.
The format of the GetColorHistogram method is:
HistogramColorPacket *GetColorHistogram( const Image *, unsigned long *colors, ExceptionInfo *);
unsigned long GetNumberColors( const Image *image, FILE *file, ExceptionInfo *exception );
Method GetNumberColors returns the number of unique colors in an image.
The format of the GetNumberColors method is:
unsigned long GetNumberColors( const Image *image, FILE *file, ExceptionInfo *exception );
MagickBool IsPaletteImage( const Image *image, ExceptionInfo *exception );
Method IsPaletteImage returns True if the image is PseudoClass and has 256 unique colors or less.
The format of the IsPaletteImage method is:
MagickBool IsPaletteImage( const Image *image, ExceptionInfo *exception );
A description of each parameter follows.