I have a bitmap that can be opened by Ristretto Image Viewer (a Linux program), but it can't be opened by Pillow. I originally encountered this with Pillow version 5.1.0. I upgraded my package to v8.4.0 to see if the issue would resolve, but the same error is raised. In v8.4.0, this error is raised on line 203 of BmpImagePlugin.py.

Upon closer inspection, it seems that the bitmap file I was trying to open has file_info['header_size'] == 124, file_info['compression'] == 3, file_info['bits'] == 32, and file_info['rgba_mask'] == (0xff000000, 0xff0000, 0xff00, 0xff).

Does my bmp file follow the BMP file format? If so, can it be supported in a future version? Thanks.