Given the symptoms: 1) Occurs during resizing using factors that are not powers of 2 (i.e., 2, 4, 8, etc.). Comment #2 2) The thatched pattern is the color (254, 254, 254), where pure white is (255, 255, 255). Attachment to Comment #1 3) Only occurs for pure white (255, 255, 255) starting image. Comment #3
I would strongly suspect that this is not a bug, but a rounding error inherent in filter. It just happens that only images starting from pure white end up with rounding errors large enough to change a pixel value by one. The Lanczos filter actually takes on negative values at places, so that might be enough to put a resampled pixel one value below where it should be when the scaling isn't a nice power of 2. In other words, this is a limitation of the filter, not a programming bug. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/648379 Title: Artifacts when scaling down with Sinc Lanczos3 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gimp/+bug/648379/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs