Category
Transformation
Function
Converts an RGB image to a byte image with a colormap
Syntax
images = QuantizeImage(Images, nColors);
Inputs
| Name
| Type
| Default
| Description
|
| images
| image, image series
| (none)
| image(s) to quantize
|
| nColors
| integer
| 256
| maximum number of colors to use
|
Outputs
| Name
| Type
| Description
|
| images
| image, image series
| resulting quantized image(s)
|
Functional Details
QuantizeImage converts an image from a format in which the "colors"
component is a list of RGB (red, green, blue) vectors, with as
many entries as there are pixels in the image, to a format
in which the "colors" component is simply a list of unsigned bytes
which are interpreted as pointers into a color table.
QuantizeImage sets a "direct color map" attribute of 1 on its
output. When the output images is passed to
Display, this will force Display to use the colormap specified by
QuantizeImage, rather than a default colormap
(see "Using Direct Color Maps"). This will
be the case even if you set the
environment variable DX8BITCMAP to 1. You can use the Options module to
set a "direct color map" attribute of 0 on the output of
QuantizeImage to force Display to use a shared colormap.
images
| is the image or series of images to be quantized.
|
nColors
| is the maximum number of entries in the color table.
|
The output images will
be a new image or series of images in which
the color table is attached as a component called "color map".
The advantage of using QuantizeImage is that the image will consume
much less memory.
Components
Changes the "colors" component. Adds a "color map" component.
Example Visual Programs
SIMPLE/QuantizeImage.net
See Also
Render,
ReadImage,
WriteImage,
Display,
Options