image processing basics

[waldronate]

ftp://69.31.121.43/developer/present...ing_Tricks.pdf is a good starting point. A lot of the GDC discussions are useful for application to real-time graphics systems today; I would recommend SIGGRAPH papers for more general research. http://kesen.realtimerendering.com/ is an excellent resource for locating many papers in the computer graphics field.

One of the fun things about graphics systems these days is that you're often looking at hundreds to thousands of processors and relatively inexpensive systems (way less than $5k) with a fair amount more than 10 teraflops of single-precision floating-point power. When you start looking at GPUs, it's often easier and sometimes faster to do all of your work directly in floating-point than try to keep everything in fixed-point or integer notations. Even for some CPU implementations these days you may find that floating-point will implement certain algorithms faster than integer.

Modern PC systems are hopelessly memory-bound and the reason that GPUs can be faster than CPUs is often that GPUs have more memory bandwidth (100s of GB/s) compared to PCs (10s of GB/s). Using half-floats can ease the pressure a little, but you have to live with the precision loss. But I would much rather code floating-point algorithms than fixed-point ones because I have fewer things to keep track of.

I'm lazy enough that I'd probably code a blur as an FFT on the image and blur kernel, multiply the two images, and then inverse FFT on the result image. That way I can get an arbitrary blur kernel for the same cost as a symmetric one (and a sharpen pretty much comes down to a divide instead of multiply).

[xoxos]

ftp://69.31.121.43/developer/present...ing_Tricks.pdf is a good starting point.

i am unable to rep you at present :p

this does demonstrate IIR lowpass (apparently a 'gaussian blur' technique) and resonant biquad filtering. i can't see any application for the latter beyond a costly and somewhat arbitrary video transform, but you never know. peanut butter and chocolate thing.

tackling mr. petzold (for whom i have no words) currently