I have a ~3Mpixel photo (jpg) that I want to reproduce in a three dimensional plot showing pixel coordinate (x and y axes) versus intensity (z axis) - the photo is basically a grey-black (has an intensity gradient) spot on a glass plate. In some imaging software it is possible to convert the image to grayscale (which might not be necessary - the image is already quite 'black and white'), and manually extract the intensity of each pixel (a number from the colour map: 1-256 (or is it 255??)) by hovering the mouse pointer over a very much zoomed picture. I have done this previously with lower resolution webcam images but I can't do it for 3Mpixels!!! Can LabVIEW help?
I've used the read jpg VI, and get my 3Mpixels of flattened data - but the numbers don't range from 1-256 as in the imaging software. This is not surprising since I haven't specified a colour map - how can I do this (use the grayscale colour map from the imaging software)?
It might also help to note that the area of the photo I'm interested in (the spot) is less than 1/4 of the total photo so I could probably cut out some of the blank space (if I knew how to use 'rect' - I don't have a clue what the description for this means "specifies the rectangle whose upper-left corner is at 0,0 and that is the exact size of the pixmap" (shown in the context help) - what is a pixmap? where are top, bottom, left and right? Surely a rectangle has top-left, top-right, bottom-left and bottom-right?
Excel (which I normally use) can't cope with a 3Mpixel plot so it would be nice if I could also PLOT the image in LabVIEW.
Help! I've attached the raw jpg image and the same converted to grayscale using PhotoImpact software.