; ; jdct.inc - private declarations for forward & reverse DCT subsystems ; ; Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB ; ; Based on the 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) ; --------------------------------------------------------------------------