|  | ; | 
|  | ; jdct.inc - private declarations for forward & reverse DCT subsystems | 
|  | ; | 
|  | ; Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB | 
|  | ; | 
|  | ; Based on | 
|  | ; x86 SIMD extension for IJG JPEG library | 
|  | ; Copyright (C) 1999-2006, MIYASAKA Masaru. | 
|  | ; For conditions of distribution and use, see copyright notice in jsimdext.inc | 
|  | ; | 
|  | ; [TAB8] | 
|  |  | 
|  | ; Each IDCT routine is responsible for range-limiting its results and | 
|  | ; converting them to unsigned form (0..MAXJSAMPLE).  The raw outputs could | 
|  | ; be quite far out of range if the input data is corrupt, so a bulletproof | 
|  | ; range-limiting step is required.  We use a mask-and-table-lookup method | 
|  | ; to do the combined operations quickly. | 
|  | ; | 
|  | %define RANGE_MASK  (MAXJSAMPLE * 4 + 3)  ; 2 bits wider than legal samples | 
|  |  | 
|  | %define ROW(n,b,s)		((b)+(n)*(s)) | 
|  | %define COL(n,b,s)		((b)+(n)*(s)*DCTSIZE) | 
|  |  | 
|  | %define DWBLOCK(m,n,b,s)	((b)+(m)*DCTSIZE*(s)+(n)*SIZEOF_DWORD) | 
|  | %define MMBLOCK(m,n,b,s)	((b)+(m)*DCTSIZE*(s)+(n)*SIZEOF_MMWORD) | 
|  | %define XMMBLOCK(m,n,b,s)	((b)+(m)*DCTSIZE*(s)+(n)*SIZEOF_XMMWORD) | 
|  |  | 
|  | ; -------------------------------------------------------------------------- |