[XviD-devel] Hadamard Transform

[Marc FD]

Hi.

About Hadamarad Transform :

@gruel
i saw your matrix was false because i used the butterfly with my
InverseHadamaradTransform routine.

in MMX, i'm fetching 8 bits data and my output is 16 bits.
I think i would use interlaving tricks to speedup vertical HT
so the 8x8 coefficients matrix would be interleaved.
but it's not a problem if you just want to compare them (SAD,SSD,MSE,ect..)

BTW, i assume DCT and HT are incompatible. false ?

@monsti.

first, i don't have nothing against you :)
have your fun.
but sending untested MMX code is _useless_
if you want to code that at my place, say it and i stop my work.

just want to say :
1) Hadamarad Transform is _very_ easy to do on lines.
try on colums (in MMX) and you'll understand why it's not _that_ easy.
2) Personnaly, I'm not speaking of _fast_ Hadamarad Transform but
_ultra-fast_ hadamarad transform : i do it in 14 MMX/ISSE instructions
(+fetch).
8x14 = 112 instructions for full 1D 8x8 stage :)
3) I don't like to code something who is coded by so else. it's how i work

so please clarify the situation.

Working on UFFHT (ultrafastforwardhararamadtransformer),
MarcFD  marc.fd@libertysurf.fr