First, let me say I am very familiar with Romain Guy's article on banding and dithering from Dec 2010.
I'm working with a 2.3 device with a 1080p frame buffer and 16bit / 565 color depth. The visual style involves many dark grey gradients (baked lighting effects, actually). I'm having significant trouble with major banding artifacts, most notably on window style background, but really on all Android View objects with subtle gradients. This is true on all application, including the launcher, but seems the most extreme on my own application. The scale of the 1080p display makes this significantly worse than a small phone display. Further, the color space aliasing that is leading to the banding is also leading to colors that are green or purple tinted relative to the surround neutral grays (artifact of the extra green bit). This is unacceptable, beyond just the banding problems. Despite numerous attempts, I see very little sign that dithering is enabled on the loaded bitmaps. Here is what I've tried: * Setting the window pixel format to RGBA_8888 (the first thing I ran to). * Using a XML bitmap to force the dithering flags (and other configurations). * Various PNG formats: indexed, greyscales, with and without alpha (I read something about Android manipulating .pngs at compile time based on the presense of the alpha). I've given up on JPEGs because they have less control over the insignificant bits of the pixel colors / hue shifts. * Manipulating the BitmapFactory.Options, where exposed to me. Is there anything I'm missing that might enable dithering programmatically? If I'm force to bake noise into the bitmaps, does anyone have any hints as to how I can make Photoshop or Gimp use a 555 colorspace? That is, I want the red, blue, and green channels to step through the neutral gradient at the same level, avoid green and purple hue shifts. -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
