How to make matlab assign RGB values from .png picture ?

I have a .png picture which represents a diagram with several color lines (SEL according to frequency). Is it possible to make Matlab recognize these colors (each lines' color) and automatically assign to them their RGB value ? I though to ind2rgb but I didn't get any valuable results so far...

This will let me to reproduce the diagram directly into Matlab and therefore to extract the SEL values I need.

Any help would be much appreciated!

Answer 1

[Image Analyst]

I don't know what SEL is, but in my File Exchange I have several color classification methods.

[justine]

SEL stands for Sound Exposure Level for which I would like to determine the values from a .png diagram. Thanks for your answer, I'm gonna take a look at your file exchange !