[MPlayer-dev-eng] explanations needed ot libmpeg2 idct.c algorithm

[mirak]

hi,

I am trying to implement the idct_row and idct_col in coldfire assembly 
using MAC instructions.
The algorithm used in idct.c seems different than a theoric idct.
I use octave/matlab to test the algorithm and don't get an expected result.
The algorithm used uses a lot of factorisation, and even when 
developping the equations, I don't get the expected equation.

I understand the shifts used, why the coef are multiplied by sqrt(2) ans 
also tha matrix multiplication behind this, but the block values doesn't 
seems to be the right ones.