My favourite part of TIFF is what they do about y-ordering. See, sometimes people think images start at the top, so the first data at y=0 is at the top of the

My favourite part of TIFF is what they do about y-ordering. See, sometimes people think images start at the top, so the first data at y=0 is at the top of the image, other people think they start at the bottom like a graph you draw in maths, were y=0 is clearly at the bottom of the image. So TIFF says: That should be a parameter of the image. Why? Well, TIFF came into existence because of scanners, when scanners were first invented each scanner would have its own data format - you're not going to store all this data because that's expensive - who owns that much tape? But when it's scanned clearly the bits you get have some sort of arrangement, maybe a bright white area is 1 and black is 0, maybe the opposite. That's kind of annoying, lets agree a standard. OK, so as Scanner Maker A my proposed standard is: Exactly what my popular A9 Scanner does No! As scanner maker B, clearly the standard should be what our BZ-20 model does No! Everybody at scanner maker C knows the obvious thing to do is derive the standard from the behaviour of our popular C5 and C10 scanners! Result: The TIFF standard says all of the above are OK, just add header data explaining what's going on. Since some scanners would scan a page from the top, those say y=0 is at the top, those vendors whose scanner works the other way say y=0 is at the bottom!