The rgb2gray function expects truecolor images of data type double and single to have values in the range [0, 1]. If an image has values outside the range [0, 1], then you can rescale values to the expected range by using the rescale function.

An RGB image, sometimes referred to as a truecolor image, is stored as an m-by-n-by-3 data array that defines red, green, and blue color components for each individual pixel. Graphics file formats store RGB images as 24-bit images where the red, green, and blue components are 8 …

In RGB images, the three color channels are red, green, and blue. For more information about the RGB color channels, see Display Separated Color Channels of RGB Image . There are other models, called color spaces, that describe colors using three different color channels.

May 26, 2017 · What I have done thus far to create RGB images is to just load a white image and seperate the red green and blue components from this image and combine them in different ways to get different colors. No this feels kind of redundant because I keep thinking that MatLab must have a built-in RGB system in which you can just write a one line code ...

The first argument Im can be a grayscale image I, truecolor image RGB, binary image BW, or the name of the file filename for an image of one of those types. example imshow( X , R , map ) displays the indexed image X with associated 2-D spatial referencing object R and colormap map .

Nov 21, 2012 · Yeah, they can be scattered about. For example there are some more IPT demo images in C:\Program Files\MATLAB\R2012b\toolbox\images\imdemos\html. Some of the images are the same as the other folder, but some are different. I don't know what the rationale is for what images go where. Plus the images are mixed up with m-files, etc.

RGB Images. The color components of an 8-bit RGB image are integers in the range [0, 255] rather than floating-point values in the range [0, 1]. A pixel whose color components are (255,255,255) is displayed as white. The image command displays an RGB image correctly whether its class is double, uint8, or uint16:

Creates a composite RGB image showing A and B overlaid in different color bands. Gray regions in the composite image show where the two images have the same intensities. Magenta and green regions show where the intensities are different. This is the default method. "blend" Overlays A and B using alpha blending.

img is an array of single, double, or uint8 values representing one or more grayscale or RGB color images, which writeVideo writes as one or more RGB video frames. Data of type single or double must be in the range [0,1], except when writing indexed AVI files.

You need to know how temperature was converted to RGB. Unfortunately that is not a linear process: for example, it is not as easy as "red increases as color increases". Thermal images also do not represent color the same way that flame color changes with temperature (flames get bluer and less visible as temperatures increase.)