Staging
v0.5.1
v0.5.1
swh:1:snp:635f4099902912592851108bcac178ff574f7c5f
Tip revision: 1da43e5e916949c8e849e656d9d05fa4b9d6836c authored by Benjamin Peterson on 26 June 2009, 13:21:52 UTC
rearrange the sections of the README, so they'll hopefully be more in the order people will interested in
rearrange the sections of the README, so they'll hopefully be more in the order people will interested in
Tip revision: 1da43e5
imghdr.py
"""Recognize image file formats based on their first few bytes."""
__all__ = ["what"]
#-------------------------#
# Recognize image headers #
#-------------------------#
def what(file, h=None):
if h is None:
if isinstance(file, str):
f = open(file, 'rb')
h = f.read(32)
else:
location = file.tell()
h = file.read(32)
file.seek(location)
f = None
else:
f = None
try:
for tf in tests:
res = tf(h, f)
if res:
return res
finally:
if f: f.close()
return None
#---------------------------------#
# Subroutines per image file type #
#---------------------------------#
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)
#--------------------#
# Small test program #
#--------------------#
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(filename, '*'))
testall(names, recursive, 0)
else:
print('*** directory (use -r) ***')
else:
print(filename + ':', end=' ')
sys.stdout.flush()
try:
print(what(filename))
except IOError:
print('*** not found ***')
if __name__ == '__main__':
test()