Initial revision

diff --git a/Lib/imghdr.py b/Lib/imghdr.py
new file mode 100644 (file)
index 0000000..b653cde
--- /dev/null
+++ b/Lib/imghdr.py
@@ -0,0 +1,98 @@
+# Recognizing image files based on their first few bytes.
+
+
+#-------------------------#
+# Recognize sound headers #
+#-------------------------#
+
+def what(filename):
+       f = open(filename, 'r')
+       h = f.read(32)
+       for tf in tests:
+               res = tf(h, f)
+               if res:
+                       return res
+       return None
+
+
+#---------------------------------#
+# Subroutines per image file type #
+#---------------------------------#
+
+tests = []
+
+def test_rgb(h, f):
+       # SGI image library
+       if h[:2] == '\001\332':
+               return 'rgb'
+
+tests.append(test_rgb)
+
+def test_gif(h, f):
+       # GIF ('87 and '89 variants)
+       if h[:6] in ('GIF87a', 'GIF89a'):
+               return 'gif'
+
+tests.append(test_gif)
+
+def test_pnm(h, f):
+       # PBM, PGM, PPM (portable {bit,gray,pix}map; together portable anymap)
+       if h[0] == 'P' and h[1] in '123456' and h[2] in ' \t\n\r':
+               return 'pnm'
+
+tests.append(test_pnm)
+
+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_rast(h, f):
+       # Sun raster file
+       if h[:4] == '\x59\xA6\x6A\x95':
+               return 'rast'
+
+tests.append(test_rast)
+
+
+#--------------------#
+# 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 ***'