如何在PHP中计算离散余弦变换（DCT）？

What I'd like here is a working, optimized version of my current code. While my function does return an array with actual results, I don't know if they are correct (I'm not a mathematics guru and I don't know Java code to compare my results against known implementations). Secondly, I'd like the function to be able to accept custom table sizes, but I don't know how to do that. Is table size equivalent to resampling the image? Am I applying the coefficients correctly?What I'd like here is a working, optimized vers