problem with image index

[bitValue,checkValue]=retrieveMessage(convertGray(i,j,3),key);

what is trying to shown by [bitValue,checkValue] ?

Answer 1

[Image Analyst]

The function retrieveMessage() returns two values. That collects the two returned values and stuffs them into the two variables, bitValue and checkValue, in your calling routine. You can give those variables any names you want - it doesn't have to be what they are called in the function definition.