18/12/2001
These files are replacement for appropriate files from 1.74 DVD2AVI
distribution. In orger to get SSE2 code work you must detect the CPU and set the IDCT_Flag to appropriate value.

And sure it will not be hard to incorporae this code to any (1.82, 1.85) version.

idctmmx.asm:
- added SSE2MMX_IDCT function fully rewritten for SSE2
- added IDCT_CONST_PREFETCH procedure to call before SSE2MMX_IDCT

getpic.c
- added call to SSE2MMS_IDCT with memory prefetch
- added call to IDCT_CONST_PREFETCH
- added SSE2 block set to 0
- added SSE2 unrolled loop and prefetch code to Add_Block function (3-4 times shorter!)

global.h
- added IDCT_SSE2MMX constant
- appropriate changes to struct CPU
- added declarations of SSE2MMX_IDCT and IDCT_CONST_PREFETCH