GeezerVison is showing octave.sourceforge.io — Function Reference: ind2gray
- : I = ind2gray (x, map)
Convert a color indexed image to a grayscale intensity image.
The image x must be an indexed image which will be converted using the
colormap cmap. If cmap does not contain enough colors for the
image, pixels in x outside the range are mapped to the last color in
the map before conversion to grayscale.
The output I is of the same class as the input x and may be
one of uint8, uint16, single, or double.
Implementation Note: There are several ways of converting colors to
grayscale intensities. This functions uses the luminance value obtained
from rgb2ntsc which is I = 0.299*R + 0.587*G + 0.114*B.
Other possibilities include the value component from rgb2hsv or
using a single color channel from ind2rgb.
See also: gray2ind, ind2rgb.
Package: octave