"qvx" <[EMAIL PROTECTED]> writes: [...] > 4. Process each line: compare pixels of each letter of alphabet with > corresponding pixels in line of input picture. This consists of loops > comparing pixel by pixel. This is my performance bottleneck. > > I'm using PIL for initial image processing. But then I use plain Python > loops for pixel matrix comparision. One nice optimization was to call > PIL.Image.getdata() at the begining and then use data[y*w+x] instead of > PIL.Image.getpixel(xy). I would like to compare each character raster > with corresponding image pixels in a "single operation" and avoid > (Python) loops. [...]
I don't know what exactly "compare" means here, so no Numeric code, but GIYF when it comes to the PIL<-->Numeric conversion (I imagine numarray is almost identical here, though I've not used it in anger): http://effbot.org/zone/pil-numpy.htm Since you mention C++, scipy.weave may also be of interest to you. John -- http://mail.python.org/mailman/listinfo/python-list
