Test script for the SGI imgfile module.
diff --git a/Lib/test/test_imgfile.py b/Lib/test/test_imgfile.py
new file mode 100755
index 0000000..1126672
--- /dev/null
+++ b/Lib/test/test_imgfile.py
@@ -0,0 +1,103 @@
+from test_support import verbose
+
+import imgfile
+
+
+def main():
+
+ getimage('test.rgb')
+ getimage('greytest.rgb')
+
+
+def getimage(name):
+ """return a tuple consisting of
+ image (in 'imgfile' format) width, height, size
+ """
+
+ import sys
+ import os
+ import string
+
+ outputfile = '/tmp/deleteme'
+
+ # try opening the name directly
+ try:
+ # This function returns a tuple (x, y, z) where x and y are the size of
+ # the image in pixels and z is the number of bytes per pixel. Only
+ # 3 byte RGB pixels and 1 byte greyscale pixels are supported.
+ sizes = imgfile.getsizes(name)
+ except imgfile.error:
+ # get a more qualified path component of the script...
+ if __name__ == '__main__':
+ ourname = sys.argv[0]
+ else: # ...or the full path of the module
+ ourname = sys.modules[__name__].__file__
+
+ parts = string.splitfields(ourname, os.sep)
+ parts[-1] = name
+ name = string.joinfields(parts, os.sep)
+ sizes = imgfile.getsizes(name)
+ if verbose:
+ print 'Opening test image: %s, sizes: %s' % (name, str(sizes))
+ # This function reads and decodes the image on the specified file,
+ # and returns it as a python string. The string has either 1 byte
+ # greyscale pixels or 4 byte RGBA pixels. The bottom left pixel
+ # is the first in the string. This format is suitable to pass
+ # to gl.lrectwrite, for instance.
+ image = imgfile.read(name)
+
+ # This function writes the RGB or greyscale data in data to
+ # image file file. x and y give the size of the image, z is
+ # 1 for 1 byte greyscale images or 3 for RGB images (which
+ # are stored as 4 byte values of which only the lower three
+ # bytes are used). These are the formats returned by gl.lrectread.
+ if verbose:
+ print 'Writing output file'
+ imgfile.write (outputfile, image, sizes[0], sizes[1], sizes[2])
+
+
+ if verbose:
+ print 'Opening scaled test image: %s, sizes: %s' % (name, str(sizes))
+ # This function is identical to read but it returns an image that
+ # is scaled to the given x and y sizes. If the filter and blur
+ # parameters are omitted scaling is done by simply dropping
+ # or duplicating pixels, so the result will be less than perfect,
+ # especially for computer-generated images. Alternatively,
+ # you can specify a filter to use to smoothen the image after
+ # scaling. The filter forms supported are 'impulse', 'box',
+ # 'triangle', 'quadratic' and 'gaussian'. If a filter is
+ # specified blur is an optional parameter specifying the
+ # blurriness of the filter. It defaults to 1.0. readscaled
+ # makes no attempt to keep the aspect ratio correct, so that
+ # is the users' responsibility.
+ if verbose:
+ print 'Filtering with "impulse"'
+ simage = imgfile.readscaled (name, sizes[0]/2, sizes[1]/2, 'impulse', 2.0)
+
+ # This function sets a global flag which defines whether the
+ # scan lines of the image are read or written from bottom to
+ # top (flag is zero, compatible with SGI GL) or from top to
+ # bottom(flag is one, compatible with X). The default is zero.
+ if verbose:
+ print 'Switching to X compatibility'
+ imgfile.ttob (1)
+
+ if verbose:
+ print 'Filtering with "triangle"'
+ simage = imgfile.readscaled (name, sizes[0]/2, sizes[1]/2, 'triangle', 3.0)
+ if verbose:
+ print 'Switching back to SGI compatibility'
+ imgfile.ttob (0)
+
+ if verbose: print 'Filtering with "quadratic"'
+ simage = imgfile.readscaled (name, sizes[0]/2, sizes[1]/2, 'quadratic')
+ if verbose: print 'Filtering with "gaussian"'
+ simage = imgfile.readscaled (name, sizes[0]/2, sizes[1]/2, 'gaussian', 1.0)
+
+ if verbose:
+ print 'Writing output file'
+ imgfile.write (outputfile, simage, sizes[0]/2, sizes[1]/2, sizes[2])
+
+ os.unlink(outputfile)
+
+main()