| | """Recognize image file formats based on their first few bytes.""" |
| |
|
| | from os import PathLike |
| |
|
| | __all__ = ["what"] |
| |
|
| | |
| | |
| | |
| |
|
| | def what(file, h=None): |
| | f = None |
| | try: |
| | if h is None: |
| | if isinstance(file, (str, PathLike)): |
| | f = open(file, 'rb') |
| | h = f.read(32) |
| | else: |
| | location = file.tell() |
| | h = file.read(32) |
| | file.seek(location) |
| | for tf in tests: |
| | res = tf(h, f) |
| | if res: |
| | return res |
| | finally: |
| | if f: f.close() |
| | return None |
| |
|
| |
|
| | |
| | |
| | |
| |
|
| | tests = [] |
| |
|
| | def test_jpeg(h, f): |
| | """JPEG data in JFIF or Exif format""" |
| | if h[6:10] in (b'JFIF', b'Exif'): |
| | return 'jpeg' |
| |
|
| | tests.append(test_jpeg) |
| |
|
| | def test_png(h, f): |
| | if h.startswith(b'\211PNG\r\n\032\n'): |
| | return 'png' |
| |
|
| | tests.append(test_png) |
| |
|
| | def test_gif(h, f): |
| | """GIF ('87 and '89 variants)""" |
| | if h[:6] in (b'GIF87a', b'GIF89a'): |
| | return 'gif' |
| |
|
| | tests.append(test_gif) |
| |
|
| | def test_tiff(h, f): |
| | """TIFF (can be in Motorola or Intel byte order)""" |
| | if h[:2] in (b'MM', b'II'): |
| | return 'tiff' |
| |
|
| | tests.append(test_tiff) |
| |
|
| | def test_rgb(h, f): |
| | """SGI image library""" |
| | if h.startswith(b'\001\332'): |
| | return 'rgb' |
| |
|
| | tests.append(test_rgb) |
| |
|
| | def test_pbm(h, f): |
| | """PBM (portable bitmap)""" |
| | if len(h) >= 3 and \ |
| | h[0] == ord(b'P') and h[1] in b'14' and h[2] in b' \t\n\r': |
| | return 'pbm' |
| |
|
| | tests.append(test_pbm) |
| |
|
| | def test_pgm(h, f): |
| | """PGM (portable graymap)""" |
| | if len(h) >= 3 and \ |
| | h[0] == ord(b'P') and h[1] in b'25' and h[2] in b' \t\n\r': |
| | return 'pgm' |
| |
|
| | tests.append(test_pgm) |
| |
|
| | def test_ppm(h, f): |
| | """PPM (portable pixmap)""" |
| | if len(h) >= 3 and \ |
| | h[0] == ord(b'P') and h[1] in b'36' and h[2] in b' \t\n\r': |
| | return 'ppm' |
| |
|
| | tests.append(test_ppm) |
| |
|
| | def test_rast(h, f): |
| | """Sun raster file""" |
| | if h.startswith(b'\x59\xA6\x6A\x95'): |
| | return 'rast' |
| |
|
| | tests.append(test_rast) |
| |
|
| | def test_xbm(h, f): |
| | """X bitmap (X10 or X11)""" |
| | if h.startswith(b'#define '): |
| | return 'xbm' |
| |
|
| | tests.append(test_xbm) |
| |
|
| | def test_bmp(h, f): |
| | if h.startswith(b'BM'): |
| | return 'bmp' |
| |
|
| | tests.append(test_bmp) |
| |
|
| | def test_webp(h, f): |
| | if h.startswith(b'RIFF') and h[8:12] == b'WEBP': |
| | return 'webp' |
| |
|
| | tests.append(test_webp) |
| |
|
| | def test_exr(h, f): |
| | if h.startswith(b'\x76\x2f\x31\x01'): |
| | return 'exr' |
| |
|
| | tests.append(test_exr) |
| |
|
| | |
| | |
| | |
| |
|
| | def test(): |
| | import sys |
| | recursive = 0 |
| | if sys.argv[1:] and sys.argv[1] == '-r': |
| | del sys.argv[1:2] |
| | recursive = 1 |
| | try: |
| | if sys.argv[1:]: |
| | testall(sys.argv[1:], recursive, 1) |
| | else: |
| | testall(['.'], recursive, 1) |
| | except KeyboardInterrupt: |
| | sys.stderr.write('\n[Interrupted]\n') |
| | sys.exit(1) |
| |
|
| | def testall(list, recursive, toplevel): |
| | import sys |
| | import os |
| | for filename in list: |
| | if os.path.isdir(filename): |
| | print(filename + '/:', end=' ') |
| | if recursive or toplevel: |
| | print('recursing down:') |
| | import glob |
| | names = glob.glob(os.path.join(glob.escape(filename), '*')) |
| | testall(names, recursive, 0) |
| | else: |
| | print('*** directory (use -r) ***') |
| | else: |
| | print(filename + ':', end=' ') |
| | sys.stdout.flush() |
| | try: |
| | print(what(filename)) |
| | except OSError: |
| | print('*** not found ***') |
| |
|
| | if __name__ == '__main__': |
| | test() |
| |
|
