gimp_histogram (1995-1996)

NAME

gimp_histogram - Returns information on the intensity histogram for the specified drawable.

SYNOPSIS

(mean,std_dev,median,pixels,count,percentile) = gimp_histogram (drawable,channel,start_range,end_range)

DESCRIPTION

This tool makes it possible to gather information about the intensity histogram of a drawable. A channel to examine is first specified. This can be either value, red, green, or blue, depending on whether the drawable is of type color or grayscale. The drawable may not be indexed. Second, a range of intensities are specified. The gimp_histogram function returns statistics based on the pixels in the drawable that fall under this range of values. Mean, standard deviation, median, number of pixels, and percentile are all returned. Additionally, the total count of pixels in the image is returned. Counts of pixels are weighted by any associated alpha values and by the current selection mask. That is, pixels that lie outside an active selection mask will not be counted. Similarly, pixels with transparent alpha values will not be counted.

INPUT ARGUMENTS

TYPE	NAME	DESCRIPTION
DRAWABLE	drawable	The drawable
INT32	channel	The channel to modify: { VALUE_LUT (0), RED_LUT (1), GREEN_LUT (2), BLUE_LUT (3), ALPHA_LUT (4) }
INT32	start_range	Start of the intensity measurement range
INT32	end_range	End of the intensity measurement range

RETURN VALUES

TYPE	NAME	DESCRIPTION
FLOAT	mean	Mean itensity value
FLOAT	std_dev	Standard deviation of intensity values
FLOAT	median	Median itensity value
FLOAT	pixels	Alpha-weighted pixel count for entire image
FLOAT	count	Alpha-weighted pixel count for range
FLOAT	percentile	Percentile that range falls under

SOME SYNTAX ALTERNATIVES

(mean,std_dev,median,pixels,count,percentile) = $drawable->histogram (channel,start_range,end_range)

AUTHOR

Spencer Kimball & Peter Mattis
(c)1995-1996 Spencer Kimball & Peter Mattis