In what conditions does an indexed image ensure the compression of a color image?

Hello! I need to make a code in matlab with indexed images and I need to ndesrtand the following thing in order to do the code: In what conditions does an indexed image ensure the compression of a color image?

Answer 1

[Image Analyst]

Under the condition that the number of colors you told it to use in rgb2ind() is less than the number of colors that are actually present in the full RGB image.

[Image Analyst]

Under the condition that the number of colors you quantify it with are less than the number of colors that are actually present in the full RGB image.

[Image Analyst]

No. I am not referring to the color map, which is like a look up table that says what integer value should get mapped to what color. "The full RGB Image" means the image itself, not the N-by-3 color map (a "look up table"). The image is a rows-by-columns-by 3 color channels array. One array holds the red values, one array holds the green values and the third channel holds the blue pixel values, and they are all collected together into a single 3-D array..