Looks like some kind of error trying to read in a PNG format file. Unfortunately, even though it is "urgent", you forgot to attach the image file, or the m-file. So I won't get to it until tomorrow. So about all I can suggest now is that your image is corrupt. Can you open it in any other program?
Maybe someone will still be able to answer today, but I suggest you read this link and improve your question and attach your files first.
