gimp_levels (1995-1996)

NAME

gimp_levels - Modifies intensity levels in the specified drawable.

SYNOPSIS

gimp_levels (drawable,channel,low_input,high_input,gamma,low_output,high_output)

DESCRIPTION

This tool allows intensity levels in the specified drawable to be remapped according to a set of parameters. The low/high input levels specify an initial mapping from the source intensities. The gamma value determines how intensities between the low and high input intensities are interpolated. A gamma value of 1.0 results in a linear interpolation. Higher gamma values result in more high-level intensities. Lower gamma values result in more low-level intensities. The low/high output levels constrain the final intensity mapping--that is, no final intensity will be lower than the low output level and no final intensity will be higher than the high output level. This tool is only valid on RGB color and grayscale images. It will not operate on indexed drawables.

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	low_input	Intensity of lowest input: (0 <= low_input <= 255)
INT32	high_input	Intensity of highest input: (0 <= high_input <= 255)
FLOAT	gamma	Gamma correction factor: (0.1 <= gamma <= 10)
INT32	low_output	Intensity of lowest output: (0 <= low_output <= 255)
INT32	high_output	Intensity of highest output: (0 <= high_output <= 255)

SOME SYNTAX ALTERNATIVES

$drawable->levels (channel,low_input,high_input,gamma,low_output,high_output)

AUTHOR

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