jdct.inc (1273B)
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 ; Each IDCT routine is responsible for range-limiting its results and 12 ; converting them to unsigned form (0..MAXJSAMPLE). The raw outputs could 13 ; be quite far out of range if the input data is corrupt, so a bulletproof 14 ; range-limiting step is required. We use a mask-and-table-lookup method 15 ; to do the combined operations quickly. 16 ; 17 %define RANGE_MASK (MAXJSAMPLE * 4 + 3) ; 2 bits wider than legal samples 18 19 %define ROW(n, b, s) ((b) + (n) * (s)) 20 %define COL(n, b, s) ((b) + (n) * (s) * DCTSIZE) 21 22 %define DWBLOCK(m, n, b, s) \ 23 ((b) + (m) * DCTSIZE * (s) + (n) * SIZEOF_DWORD) 24 %define MMBLOCK(m, n, b, s) \ 25 ((b) + (m) * DCTSIZE * (s) + (n) * SIZEOF_MMWORD) 26 %define XMMBLOCK(m, n, b, s) \ 27 ((b) + (m) * DCTSIZE * (s) + (n) * SIZEOF_XMMWORD) 28 %define YMMBLOCK(m, n, b, s) \ 29 ((b) + (m) * DCTSIZE * (s) + (n) * SIZEOF_YMMWORD) 30 31 ; --------------------------------------------------------------------------