1; 2; jdct.inc - private declarations for forward & reverse DCT subsystems 3; 4; Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB 5; Copyright (C) 2018, D. R. Commander. 6; 7; Based on the x86 SIMD extension for IJG JPEG library 8; Copyright (C) 1999-2006, MIYASAKA Masaru. 9; For conditions of distribution and use, see copyright notice in jsimdext.inc 10; 11; [TAB8] 12 13; Each IDCT routine is responsible for range-limiting its results and 14; converting them to unsigned form (0..MAXJSAMPLE). The raw outputs could 15; be quite far out of range if the input data is corrupt, so a bulletproof 16; range-limiting step is required. We use a mask-and-table-lookup method 17; to do the combined operations quickly. 18; 19%define RANGE_MASK (MAXJSAMPLE * 4 + 3) ; 2 bits wider than legal samples 20 21%define ROW(n, b, s) ((b) + (n) * (s)) 22%define COL(n, b, s) ((b) + (n) * (s) * DCTSIZE) 23 24%define DWBLOCK(m, n, b, s) \ 25 ((b) + (m) * DCTSIZE * (s) + (n) * SIZEOF_DWORD) 26%define MMBLOCK(m, n, b, s) \ 27 ((b) + (m) * DCTSIZE * (s) + (n) * SIZEOF_MMWORD) 28%define XMMBLOCK(m, n, b, s) \ 29 ((b) + (m) * DCTSIZE * (s) + (n) * SIZEOF_XMMWORD) 30%define YMMBLOCK(m, n, b, s) \ 31 ((b) + (m) * DCTSIZE * (s) + (n) * SIZEOF_YMMWORD) 32 33; -------------------------------------------------------------------------- 34