NAME

colors - Count the Colors in an Image

SYNOPSIS

DestroyList(node)

Histogram(node,file)

node=InitializeNode(level)

status=IsPseudoClass(image)

NumberColors(image,file)

FUNCTION DESCRIPTIONS

DestroyList

Procedure DestroyList traverses the color cube tree and free the list of unique colors.

The format of the DestroyList routine is: 

        DestroyList(node)

A description of each parameter follows.

o node:
The address of a structure of type Node which points to a node in the color cube tree that is to be pruned.

Histogram

Procedure Histogram traverses the color cube tree and produces a list of unique pixel field values and the number of times each occurs in the image.

The format of the Histogram routine is: 

        Histogram(node,file)

A description of each parameter follows.

o node:
The address of a structure of type Node which points to a node in the color cube tree that is to be pruned.

InitializeNode

Function InitializeNode allocates memory for a new node in the color cube tree and presets all fields to zero.

The format of the InitializeNode routine is: 

        node=InitializeNode(level)

A description of each parameter follows.

o level:
Specifies the level in the classification the node resides.

IsPseudoClass

Function IsPseudoClass returns True if the image is PseudoClass and has 256 unique colors or less. If the image is DirectClass and has less 256 colors or less, the image is demoted to PseudoClass.

The format of the IsPseudoClass routine is: 

        status=IsPseudoClass(image)

A description of each parameter follows.

o status:
Function IsPseudoClass returns True is the image is PseudoClass or has 256 color or less.

o image:
The address of a byte (8 bits) array of run-length encoded pixel data of your source image. The sum of the run-length counts in the source image must be equal to or exceed the number of pixels.

NumberColors

Function NumberColors returns the number of unique colors in an image.

The format of the NumberColors routine is: 

        NumberColors(image,file)

A description of each parameter follows.

o image:
The address of a byte (8 bits) array of run-length encoded pixel data of your source image. The sum of the run-length counts in the source image must be equal to or exceed the number of pixels.

o file:
An pointer to a FILE. If it is non-null a list of unique pixel field values and the number of times each occurs in the image is written to the file.