Function Reference

Image Processing

Loading and Saving Images

imread
Read images from various file formats.
imwrite
Write image from octave to various file formats
IMAGE_PATH
Query or set the internal variable that specifies a colon separated list of directories in which to search for image files.
imfinfo
Read image information from a file.

Displaying Images

imshow
Display the image IM, where IM can be a 2-dimensional (gray-scale image) or a 3-dimensional (RGB image) matrix.
image
Display a matrix as a color image.
imagesc
Display a scaled version of the matrix A as a color image.
image_viewer
Change the program or function used for viewing images and return the previous values.

Representing Images

gray2ind
Convert a gray scale intensity image to an Octave indexed image.
ind2gray
Convert an Octave indexed image to a gray scale intensity image.
rgb2ind
Convert and RGB image to an Octave indexed image.
ind2rgb
Convert an indexed image to red, green, and blue color components.
colormap
Set the current colormap.
autumn
Create color colormap.
bone
Create color colormap.
cool
Create color colormap.
copper
Create color colormap.
gray
Return a gray colormap with N entries corresponding to values from 0 to N-1.
hot
Create color colormap.
hsv
Create color colormap.
jet
Create color colormap.
ocean
Create color colormap.
pink
Create color colormap.
prism
Create color colormap.
rainbow
Create color colormap.
spring
Create color colormap.
summer
Create color colormap.
white
Create color colormap.
winter
Create color colormap.
contrast
Return a gray colormap that maximizes the contrast in an image.
gmap40
Create a color colormap.

Color Conversion

rgb2hsv
Transform a colormap or image from the rgb space to the hsv space.
hsv2rgb
Transform a colormap or image from the hsv space to the rgb space.
rgb2ntsc
Transform a colormap or image from RGB to NTSC.
ntsc2rgb
Transform a colormap or image from NTSC to RGB.