Hi list, I'm trying to create a ConTeXt document that searches for image-files (png, jpg, any, whatever... that's not important) in the same directory and processes all found images in a certain way. I'm pretty sure that parsing the directory should work with lua in ConTeXt, but I'm stuck at the part where I want lua to process the image. Is it somehow possible to get the color of an arbitrary pixel in the image (file) given the vertical and horizontal position of the pixel? I could process the images beforehand with another application (which does not yet exist) and write its output to ASCII files or something, but I rather avoid that. If that's the only possibility, how would I call another application while processing a tex file with ConTeXt? Thanks in advance for any hints, Stefan