v1.9.0

Added

• ImageFrame.ReleaseDecodedPixels() is public, so one frame of a multi-frame image can give its decoded pixels back.
• CopyPixelsTo(destination, rect, useRegionCache: false) on Image and ImageFrame: one region or band read that builds no region plane and counts toward none, whatever ImageEngine.RegionCacheBytes says. Bands read from the top down decode the image once and hold only the decoder's few tile rows; a read that has to go back above them decodes again for that call and keeps nothing afterwards. Pixels are identical.

Fixed

• ReleaseDecodedPixels() now gives back everything decode-derived: it also clears the cached tiles of every operation above the decode (a gray conversion, a resize) and of a random-access decode (TIFF), where before only the region plane and sequential-decode rows went. Releasing through frame.ToImage() (or the image the frame came from) now frees the frame's region plane; planes used to belong to the frame object, so a single-frame image made from it had its own empty set.