how can i convert RGB image to YCBCR image

i used the simple function rgb2ycbcr but an error appeared:

Answer 1

[Geoff Hayes]

si - what can you tell us about the input parameter a? What are its dimensions? According to the documentation for rgb2ycbcr, the input, if a map, must be of dimension mx3, and if the input is an RGB image, then it must be of dimension mxnx3. I suspect that your a is two dimensional.

Answer 2

[Walter Roberson]

The a that you are passing in is not an RGB array. It is either a grayscale matrix (floating point) or a label matrix (integer values that indicate which color number appears at that location.)