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v0.8.1
v0.8.1
swh:1:snp:635f4099902912592851108bcac178ff574f7c5f
Tip revision: 74f4bd53e03ded8408bcc2de67cf0f5a4ac5b1a1 authored by Barry Warsaw on 23 February 2012, 15:59:38 UTC
Bump some more copyright years (as per PEP 101), since this is the first
Bump some more copyright years (as per PEP 101), since this is the first
Tip revision: 74f4bd5
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, basestring):
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 format"""
if h[6:10] == 'JFIF':
return 'jpeg'
tests.append(test_jpeg)
def test_exif(h, f):
"""JPEG data in Exif format"""
if h[6:10] == 'Exif':
return 'jpeg'
tests.append(test_exif)
def test_png(h, f):
if h[:8] == "\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 ('GIF87a', '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 ('MM', 'II'):
return 'tiff'
tests.append(test_tiff)
def test_rgb(h, f):
"""SGI image library"""
if h[:2] == '\001\332':
return 'rgb'
tests.append(test_rgb)
def test_pbm(h, f):
"""PBM (portable bitmap)"""
if len(h) >= 3 and \
h[0] == 'P' and h[1] in '14' and h[2] in ' \t\n\r':
return 'pbm'
tests.append(test_pbm)
def test_pgm(h, f):
"""PGM (portable graymap)"""
if len(h) >= 3 and \
h[0] == 'P' and h[1] in '25' and h[2] in ' \t\n\r':
return 'pgm'
tests.append(test_pgm)
def test_ppm(h, f):
"""PPM (portable pixmap)"""
if len(h) >= 3 and \
h[0] == 'P' and h[1] in '36' and h[2] in ' \t\n\r':
return 'ppm'
tests.append(test_ppm)
def test_rast(h, f):
"""Sun raster file"""
if h[:4] == '\x59\xA6\x6A\x95':
return 'rast'
tests.append(test_rast)
def test_xbm(h, f):
"""X bitmap (X10 or X11)"""
s = '#define '
if h[:len(s)] == s:
return 'xbm'
tests.append(test_xbm)
def test_bmp(h, f):
if h[:2] == '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 + '/:',
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 + ':',
sys.stdout.flush()
try:
print what(filename)
except IOError:
print '*** not found ***'