[Image-SIG] Comparison of PIL and GD speed for setting pixels through python

[John Barratt]

Hi,
	I've had a need to do some optimisation of some low level pixel setting 
code, and have as such done some tests of different ways of doing this 
using PIL and alternatively with gd via ctypes.

Ctypes provides a fairly easy way to interface to gd, and allows you to 
easily use small sections of optimising C code.  A summary of the 
results is below, but basically using ctyles/GD/c is about 20 or so 
times faster than PIL and the new Image.load, and over 200 times faster 
than using PIL's ImageDraw.point method.

Method          Time (s)        Times slower than fastest
+-----+         +-------+       +------------------------+
ctypes, c, GD   0.00181         1.0
PIL - 'load'    0.03965         21.9
ctypes, GD      0.18710         103.5
PIL - 'point'   0.45009         248.9

A full writeup of this can be found here :

http://www.langarson.com.au/blog/?p=10

I hope this is of use, and I look forward to comments, particularly on 
other ways of doing this with PIL & C, which there undoubtedly are.

Cheers,

JB.

-- 
John Barratt
www.langarson.com.au - Python, Zope, GIS, Weather.