How should we handle incomplete files? ====================================== Reading an incomplete TIFF sets i_incomplete, but no others do. Should this only occur if a flag is set? Should there be some indication of how much was read? Some formats, like compressed BMP don't really have a way to tell. A valid BMP might be 100 x 100 and only set 1 pixel in the data. Though we can't tell what the non-set pixels should be in this case.