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author | nobody <nobody@ae88bc3d-4319-0410-8dbf-d08b4c9d3795> | 1999-01-14 08:34:01 +0000 |
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committer | nobody <nobody@ae88bc3d-4319-0410-8dbf-d08b4c9d3795> | 1999-01-14 08:34:01 +0000 |
commit | 12521f45cd85d2e89125c532bdb0df62409bf164 (patch) | |
tree | 832e81ec9b3c5b3b540d569bb4526b23c848c6b2 /TAO/orbsvcs/tests/AVStreams/mpeg/source/mpeg_client/jrevdct.cpp | |
parent | 8f4d76cd59b787031f27fb40c2e3c473e86a3834 (diff) | |
download | ATCD-ACE-4_6_13.tar.gz |
This commit was manufactured by cvs2svn to create tag 'ACE-4_6_13'.ACE-4_6_13
Diffstat (limited to 'TAO/orbsvcs/tests/AVStreams/mpeg/source/mpeg_client/jrevdct.cpp')
-rw-r--r-- | TAO/orbsvcs/tests/AVStreams/mpeg/source/mpeg_client/jrevdct.cpp | 1461 |
1 files changed, 0 insertions, 1461 deletions
diff --git a/TAO/orbsvcs/tests/AVStreams/mpeg/source/mpeg_client/jrevdct.cpp b/TAO/orbsvcs/tests/AVStreams/mpeg/source/mpeg_client/jrevdct.cpp deleted file mode 100644 index 6114517c580..00000000000 --- a/TAO/orbsvcs/tests/AVStreams/mpeg/source/mpeg_client/jrevdct.cpp +++ /dev/null @@ -1,1461 +0,0 @@ -/* $Id$ */ - -/* - * jrevdct.c - * - * Copyright (C) 1991, 1992, Thomas G. Lane. - * This file is part of the Independent JPEG Group's software. - * For conditions of distribution and use, see the accompanying README file. - * - * This file contains the basic inverse-DCT transformation subroutine. - * - * This implementation is based on an algorithm described in - * C. Loeffler, A. Ligtenberg and G. Moschytz, "Practical Fast 1-D DCT - * Algorithms with 11 Multiplications", Proc. Int'l. Conf. on Acoustics, - * Speech, and Signal Processing 1989 (ICASSP '89), pp. 988-991. - * The primary algorithm described there uses 11 multiplies and 29 adds. - * We use their alternate method with 12 multiplies and 32 adds. - * The advantage of this method is that no data path contains more than one - * multiplication; this allows a very simple and accurate implementation in - * scaled fixed-point arithmetic, with a minimal number of shifts. - * - * I've made lots of modifications to attempt to take advantage of the - * sparse nature of the DCT matrices we're getting. Although the logic - * is cumbersome, it's straightforward and the resulting code is much - * faster. - * - * A better way to do this would be to pass in the DCT block as a sparse - * matrix, perhaps with the difference cases encoded. - */ - -#include <string.h> -#include "video.h" -#include "proto.h" -#include "ace/OS.h" - -ACE_RCSID(mpeg_client, jrevdct, "$Id$") - -#define GLOBAL /* a function referenced thru EXTERNs */ - -/* We assume that right shift corresponds to signed division by 2 with - * rounding towards minus infinity. This is correct for typical "arithmetic - * shift" instructions that shift in copies of the sign bit. But some - * C compilers implement >> with an unsigned shift. For these machines you - * must define RIGHT_SHIFT_IS_UNSIGNED. - * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity. - * It is only applied with constant shift counts. SHIFT_TEMPS must be - * included in the variables of any routine using RIGHT_SHIFT. - */ - -#ifdef RIGHT_SHIFT_IS_UNSIGNED -#define SHIFT_TEMPS INT32 shift_temp; -#define RIGHT_SHIFT(x,shft) \ - ((shift_temp = (x)) < 0 ? \ - (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \ - (shift_temp >> (shft))) -#else -#define SHIFT_TEMPS -#define RIGHT_SHIFT(x,shft) ((x) >> (shft)) -#endif - -/* - * This routine is specialized to the case DCTSIZE = 8. - */ - -#if DCTSIZE != 8 - Sorry, this code only copes with 8x8 DCTs. /* deliberate syntax err */ -#endif - - -/* - * A 2-D IDCT can be done by 1-D IDCT on each row followed by 1-D IDCT - * on each column. Direct algorithms are also available, but they are - * much more complex and seem not to be any faster when reduced to code. - * - * The poop on this scaling stuff is as follows: - * - * Each 1-D IDCT step produces outputs which are a factor of sqrt(N) - * larger than the true IDCT outputs. The final outputs are therefore - * a factor of N larger than desired; since N=8 this can be cured by - * a simple right shift at the end of the algorithm. The advantage of - * this arrangement is that we save two multiplications per 1-D IDCT, - * because the y0 and y4 inputs need not be divided by sqrt(N). - * - * We have to do addition and subtraction of the integer inputs, which - * is no problem, and multiplication by fractional constants, which is - * a problem to do in integer arithmetic. We multiply all the constants - * by CONST_SCALE and convert them to integer constants (thus retaining - * CONST_BITS bits of precision in the constants). After doing a - * multiplication we have to divide the product by CONST_SCALE, with proper - * rounding, to produce the correct output. This division can be done - * cheaply as a right shift of CONST_BITS bits. We postpone shifting - * as long as possible so that partial sums can be added together with - * full fractional precision. - * - * The outputs of the first pass are scaled up by PASS1_BITS bits so that - * they are represented to better-than-integral precision. These outputs - * require BITS_IN_JSAMPLE + PASS1_BITS + 3 bits; this fits in a 16-bit word - * with the recommended scaling. (To scale up 12-bit sample data further, an - * intermediate INT32 array would be needed.) - * - * To avoid overflow of the 32-bit intermediate results in pass 2, we must - * have BITS_IN_JSAMPLE + CONST_BITS + PASS1_BITS <= 26. Error analysis - * shows that the values given below are the most effective. - */ - -#ifdef EIGHT_BIT_SAMPLES -#define PASS1_BITS 2 -#else -#define PASS1_BITS 1 /* lose a little precision to avoid overflow */ -#endif - -#define ONE ((INT32) 1) - -#define CONST_SCALE (ONE << CONST_BITS) - -/* Convert a positive real constant to an integer scaled by CONST_SCALE. - * IMPORTANT: if your compiler doesn't do this arithmetic at compile time, - * you will pay a significant penalty in run time. In that case, figure - * the correct integer constant values and insert them by hand. - */ - -#define FIX(x) ((INT32) ((x) * CONST_SCALE + 0.5)) - -/* Descale and correctly round an INT32 value that's scaled by N bits. - * We assume RIGHT_SHIFT rounds towards minus infinity, so adding - * the fudge factor is correct for either sign of X. - */ - -#define DESCALE(x,n) RIGHT_SHIFT((x) + (ONE << ((n)-1)), n) - -/* Multiply an INT32 variable by an INT32 constant to yield an INT32 result. - * For 8-bit samples with the recommended scaling, all the variable - * and constant values involved are no more than 16 bits wide, so a - * 16x16->32 bit multiply can be used instead of a full 32x32 multiply; - * this provides a useful speedup on many machines. - * There is no way to specify a 16x16->32 multiply in portable C, but - * some C compilers will do the right thing if you provide the correct - * combination of casts. - * NB: for 12-bit samples, a full 32-bit multiplication will be needed. - */ - -#ifdef EIGHT_BIT_SAMPLES -#ifdef SHORTxSHORT_32 /* may work if 'int' is 32 bits */ -#define MULTIPLY(var,const) (((INT16) (var)) * ((INT16) (const))) -#endif -#ifdef SHORTxLCONST_32 /* known to work with Microsoft C 6.0 */ -#define MULTIPLY(var,const) (((INT16) (var)) * ((INT32) (const))) -#endif -#endif - -#ifndef MULTIPLY /* default definition */ -#define MULTIPLY(var,const) ((var) * (const)) -#endif - -/* Precomputed idct value arrays. */ - -static DCTELEM PreIDCT[64][64]; - -void j_rev_dct (DCTBLOCK data); - -/* Pre compute singleton coefficient IDCT values. */ -void -init_pre_idct() { - int i; - - for (i=0; i<64; i++) { - memset((char *) PreIDCT[i], 0, 64*sizeof(DCTELEM)); - PreIDCT[i][i] = 2048; - j_rev_dct(PreIDCT[i]); - } -} - -#ifndef ORIG_DCT - - -/* - * Perform the inverse DCT on one block of coefficients. - */ - -void -j_rev_dct_sparse (DCTBLOCK data, int pos) -{ - register DCTELEM *dataptr; - short int val; - DCTELEM *ndataptr; - int scale, coeff, rr; - register int *dp; - register int v; - - /* If DC Coefficient. */ - - if (pos == 0) { - dp = (int *)data; - v = *data; - /* Compute 32 bit value to assign. This speeds things up a bit */ - if (v < 0) val = (v-3)>>3; - else val = (v+4)>>3; - v = val | (val << 16); - dp[0] = v; dp[1] = v; dp[2] = v; dp[3] = v; - dp[4] = v; dp[5] = v; dp[6] = v; dp[7] = v; - dp[8] = v; dp[9] = v; dp[10] = v; dp[11] = v; - dp[12] = v; dp[13] = v; dp[14] = v; dp[15] = v; - dp[16] = v; dp[17] = v; dp[18] = v; dp[19] = v; - dp[20] = v; dp[21] = v; dp[22] = v; dp[23] = v; - dp[24] = v; dp[25] = v; dp[26] = v; dp[27] = v; - dp[28] = v; dp[29] = v; dp[30] = v; dp[31] = v; - return; - } - - /* Some other coefficient. */ - dataptr = (DCTELEM *)data; - coeff = dataptr[pos]; - ndataptr = PreIDCT[pos]; - - for (rr=0; rr<4; rr++) { - dataptr[0] = (ndataptr[0] * coeff) >> (CONST_BITS-2); - dataptr[1] = (ndataptr[1] * coeff) >> (CONST_BITS-2); - dataptr[2] = (ndataptr[2] * coeff) >> (CONST_BITS-2); - dataptr[3] = (ndataptr[3] * coeff) >> (CONST_BITS-2); - dataptr[4] = (ndataptr[4] * coeff) >> (CONST_BITS-2); - dataptr[5] = (ndataptr[5] * coeff) >> (CONST_BITS-2); - dataptr[6] = (ndataptr[6] * coeff) >> (CONST_BITS-2); - dataptr[7] = (ndataptr[7] * coeff) >> (CONST_BITS-2); - dataptr[8] = (ndataptr[8] * coeff) >> (CONST_BITS-2); - dataptr[9] = (ndataptr[9] * coeff) >> (CONST_BITS-2); - dataptr[10] = (ndataptr[10] * coeff) >> (CONST_BITS-2); - dataptr[11] = (ndataptr[11] * coeff) >> (CONST_BITS-2); - dataptr[12] = (ndataptr[12] * coeff) >> (CONST_BITS-2); - dataptr[13] = (ndataptr[13] * coeff) >> (CONST_BITS-2); - dataptr[14] = (ndataptr[14] * coeff) >> (CONST_BITS-2); - dataptr[15] = (ndataptr[15] * coeff) >> (CONST_BITS-2); - dataptr += 16; - ndataptr += 16; - } - return; -} - - -void -j_rev_dct (DCTBLOCK data) -{ - INT32 tmp0, tmp1, tmp2, tmp3; - INT32 tmp10, tmp11, tmp12, tmp13; - INT32 z1, z2, z3, z4, z5; - INT32 d0, d1, d2, d3, d4, d5, d6, d7; - register DCTELEM *dataptr; - int rowctr; - SHIFT_TEMPS - - /* Pass 1: process rows. */ - /* Note results are scaled up by sqrt(8) compared to a true IDCT; */ - /* furthermore, we scale the results by 2**PASS1_BITS. */ - - dataptr = data; - - for (rowctr = DCTSIZE-1; rowctr >= 0; rowctr--) { - /* Due to quantization, we will usually find that many of the input - * coefficients are zero, especially the AC terms. We can exploit this - * by short-circuiting the IDCT calculation for any row in which all - * the AC terms are zero. In that case each output is equal to the - * DC coefficient (with scale factor as needed). - * With typical images and quantization tables, half or more of the - * row DCT calculations can be simplified this way. - */ - - register int *idataptr = (int*)dataptr; - d0 = dataptr[0]; - d1 = dataptr[1]; - if ((d1 == 0) && (idataptr[1] | idataptr[2] | idataptr[3]) == 0) { - /* AC terms all zero */ - if (d0) { - /* Compute a 32 bit value to assign. */ - DCTELEM dcval = (DCTELEM) (d0 << PASS1_BITS); - register int v = (dcval & 0xffff) | ((dcval << 16) & 0xffff0000); - - idataptr[0] = v; - idataptr[1] = v; - idataptr[2] = v; - idataptr[3] = v; - } - - dataptr += DCTSIZE; /* advance pointer to next row */ - continue; - } - d2 = dataptr[2]; - d3 = dataptr[3]; - d4 = dataptr[4]; - d5 = dataptr[5]; - d6 = dataptr[6]; - d7 = dataptr[7]; - - /* Even part: reverse the even part of the forward DCT. */ - /* The rotator is sqrt(2)*c(-6). */ - if (d6) { - if (d4) { - if (d2) { - if (d0) { - /* d0 != 0, d2 != 0, d4 != 0, d6 != 0 */ - z1 = MULTIPLY(d2 + d6, FIX(0.541196100)); - tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065)); - tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865)); - - tmp0 = (d0 + d4) << CONST_BITS; - tmp1 = (d0 - d4) << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp1 + tmp2; - tmp12 = tmp1 - tmp2; - } else { - /* d0 == 0, d2 != 0, d4 != 0, d6 != 0 */ - z1 = MULTIPLY(d2 + d6, FIX(0.541196100)); - tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065)); - tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865)); - - tmp0 = d4 << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp2 - tmp0; - tmp12 = -(tmp0 + tmp2); - } - } else { - if (d0) { - /* d0 != 0, d2 == 0, d4 != 0, d6 != 0 */ - tmp2 = MULTIPLY(d6, - FIX(1.306562965)); - tmp3 = MULTIPLY(d6, FIX(0.541196100)); - - tmp0 = (d0 + d4) << CONST_BITS; - tmp1 = (d0 - d4) << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp1 + tmp2; - tmp12 = tmp1 - tmp2; - } else { - /* d0 == 0, d2 == 0, d4 != 0, d6 != 0 */ - tmp2 = MULTIPLY(d6, -FIX(1.306562965)); - tmp3 = MULTIPLY(d6, FIX(0.541196100)); - - tmp0 = d4 << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp2 - tmp0; - tmp12 = -(tmp0 + tmp2); - } - } - } else { - if (d2) { - if (d0) { - /* d0 != 0, d2 != 0, d4 == 0, d6 != 0 */ - z1 = MULTIPLY(d2 + d6, FIX(0.541196100)); - tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065)); - tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865)); - - tmp0 = d0 << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp0 + tmp2; - tmp12 = tmp0 - tmp2; - } else { - /* d0 == 0, d2 != 0, d4 == 0, d6 != 0 */ - z1 = MULTIPLY(d2 + d6, FIX(0.541196100)); - tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065)); - tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865)); - - tmp10 = tmp3; - tmp13 = -tmp3; - tmp11 = tmp2; - tmp12 = -tmp2; - } - } else { - if (d0) { - /* d0 != 0, d2 == 0, d4 == 0, d6 != 0 */ - tmp2 = MULTIPLY(d6, - FIX(1.306562965)); - tmp3 = MULTIPLY(d6, FIX(0.541196100)); - - tmp0 = d0 << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp0 + tmp2; - tmp12 = tmp0 - tmp2; - } else { - /* d0 == 0, d2 == 0, d4 == 0, d6 != 0 */ - tmp2 = MULTIPLY(d6, - FIX(1.306562965)); - tmp3 = MULTIPLY(d6, FIX(0.541196100)); - - tmp10 = tmp3; - tmp13 = -tmp3; - tmp11 = tmp2; - tmp12 = -tmp2; - } - } - } - } else { - if (d4) { - if (d2) { - if (d0) { - /* d0 != 0, d2 != 0, d4 != 0, d6 == 0 */ - tmp2 = MULTIPLY(d2, FIX(0.541196100)); - tmp3 = MULTIPLY(d2, FIX(1.306562965)); - - tmp0 = (d0 + d4) << CONST_BITS; - tmp1 = (d0 - d4) << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp1 + tmp2; - tmp12 = tmp1 - tmp2; - } else { - /* d0 == 0, d2 != 0, d4 != 0, d6 == 0 */ - tmp2 = MULTIPLY(d2, FIX(0.541196100)); - tmp3 = MULTIPLY(d2, FIX(1.306562965)); - - tmp0 = d4 << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp2 - tmp0; - tmp12 = -(tmp0 + tmp2); - } - } else { - if (d0) { - /* d0 != 0, d2 == 0, d4 != 0, d6 == 0 */ - tmp10 = tmp13 = (d0 + d4) << CONST_BITS; - tmp11 = tmp12 = (d0 - d4) << CONST_BITS; - } else { - /* d0 == 0, d2 == 0, d4 != 0, d6 == 0 */ - tmp10 = tmp13 = d4 << CONST_BITS; - tmp11 = tmp12 = -tmp10; - } - } - } else { - if (d2) { - if (d0) { - /* d0 != 0, d2 != 0, d4 == 0, d6 == 0 */ - tmp2 = MULTIPLY(d2, FIX(0.541196100)); - tmp3 = MULTIPLY(d2, FIX(1.306562965)); - - tmp0 = d0 << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp0 + tmp2; - tmp12 = tmp0 - tmp2; - } else { - /* d0 == 0, d2 != 0, d4 == 0, d6 == 0 */ - tmp2 = MULTIPLY(d2, FIX(0.541196100)); - tmp3 = MULTIPLY(d2, FIX(1.306562965)); - - tmp10 = tmp3; - tmp13 = -tmp3; - tmp11 = tmp2; - tmp12 = -tmp2; - } - } else { - if (d0) { - /* d0 != 0, d2 == 0, d4 == 0, d6 == 0 */ - tmp10 = tmp13 = tmp11 = tmp12 = d0 << CONST_BITS; - } else { - /* d0 == 0, d2 == 0, d4 == 0, d6 == 0 */ - tmp10 = tmp13 = tmp11 = tmp12 = 0; - } - } - } - } - - - /* Odd part per figure 8; the matrix is unitary and hence its - * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively. - */ - - if (d7) { - if (d5) { - if (d3) { - if (d1) { - /* d1 != 0, d3 != 0, d5 != 0, d7 != 0 */ - z1 = d7 + d1; - z2 = d5 + d3; - z3 = d7 + d3; - z4 = d5 + d1; - z5 = MULTIPLY(z3 + z4, FIX(1.175875602)); - - tmp0 = MULTIPLY(d7, FIX(0.298631336)); - tmp1 = MULTIPLY(d5, FIX(2.053119869)); - tmp2 = MULTIPLY(d3, FIX(3.072711026)); - tmp3 = MULTIPLY(d1, FIX(1.501321110)); - z1 = MULTIPLY(z1, - FIX(0.899976223)); - z2 = MULTIPLY(z2, - FIX(2.562915447)); - z3 = MULTIPLY(z3, - FIX(1.961570560)); - z4 = MULTIPLY(z4, - FIX(0.390180644)); - - z3 += z5; - z4 += z5; - - tmp0 += z1 + z3; - tmp1 += z2 + z4; - tmp2 += z2 + z3; - tmp3 += z1 + z4; - } else { - /* d1 == 0, d3 != 0, d5 != 0, d7 != 0 */ - z1 = d7; - z2 = d5 + d3; - z3 = d7 + d3; - z5 = MULTIPLY(z3 + d5, FIX(1.175875602)); - - tmp0 = MULTIPLY(d7, FIX(0.298631336)); - tmp1 = MULTIPLY(d5, FIX(2.053119869)); - tmp2 = MULTIPLY(d3, FIX(3.072711026)); - z1 = MULTIPLY(d7, - FIX(0.899976223)); - z2 = MULTIPLY(z2, - FIX(2.562915447)); - z3 = MULTIPLY(z3, - FIX(1.961570560)); - z4 = MULTIPLY(d5, - FIX(0.390180644)); - - z3 += z5; - z4 += z5; - - tmp0 += z1 + z3; - tmp1 += z2 + z4; - tmp2 += z2 + z3; - tmp3 = z1 + z4; - } - } else { - if (d1) { - /* d1 != 0, d3 == 0, d5 != 0, d7 != 0 */ - z1 = d7 + d1; - z2 = d5; - z3 = d7; - z4 = d5 + d1; - z5 = MULTIPLY(z3 + z4, FIX(1.175875602)); - - tmp0 = MULTIPLY(d7, FIX(0.298631336)); - tmp1 = MULTIPLY(d5, FIX(2.053119869)); - tmp3 = MULTIPLY(d1, FIX(1.501321110)); - z1 = MULTIPLY(z1, - FIX(0.899976223)); - z2 = MULTIPLY(d5, - FIX(2.562915447)); - z3 = MULTIPLY(d7, - FIX(1.961570560)); - z4 = MULTIPLY(z4, - FIX(0.390180644)); - - z3 += z5; - z4 += z5; - - tmp0 += z1 + z3; - tmp1 += z2 + z4; - tmp2 = z2 + z3; - tmp3 += z1 + z4; - } else { - /* d1 == 0, d3 == 0, d5 != 0, d7 != 0 */ - tmp0 = MULTIPLY(d7, - FIX(0.601344887)); - z1 = MULTIPLY(d7, - FIX(0.899976223)); - z3 = MULTIPLY(d7, - FIX(1.961570560)); - tmp1 = MULTIPLY(d5, - FIX(0.509795578)); - z2 = MULTIPLY(d5, - FIX(2.562915447)); - z4 = MULTIPLY(d5, - FIX(0.390180644)); - z5 = MULTIPLY(d5 + d7, FIX(1.175875602)); - - z3 += z5; - z4 += z5; - - tmp0 += z3; - tmp1 += z4; - tmp2 = z2 + z3; - tmp3 = z1 + z4; - } - } - } else { - if (d3) { - if (d1) { - /* d1 != 0, d3 != 0, d5 == 0, d7 != 0 */ - z1 = d7 + d1; - z3 = d7 + d3; - z5 = MULTIPLY(z3 + d1, FIX(1.175875602)); - - tmp0 = MULTIPLY(d7, FIX(0.298631336)); - tmp2 = MULTIPLY(d3, FIX(3.072711026)); - tmp3 = MULTIPLY(d1, FIX(1.501321110)); - z1 = MULTIPLY(z1, - FIX(0.899976223)); - z2 = MULTIPLY(d3, - FIX(2.562915447)); - z3 = MULTIPLY(z3, - FIX(1.961570560)); - z4 = MULTIPLY(d1, - FIX(0.390180644)); - - z3 += z5; - z4 += z5; - - tmp0 += z1 + z3; - tmp1 = z2 + z4; - tmp2 += z2 + z3; - tmp3 += z1 + z4; - } else { - /* d1 == 0, d3 != 0, d5 == 0, d7 != 0 */ - z3 = d7 + d3; - - tmp0 = MULTIPLY(d7, - FIX(0.601344887)); - z1 = MULTIPLY(d7, - FIX(0.899976223)); - tmp2 = MULTIPLY(d3, FIX(0.509795579)); - z2 = MULTIPLY(d3, - FIX(2.562915447)); - z5 = MULTIPLY(z3, FIX(1.175875602)); - z3 = MULTIPLY(z3, - FIX(0.785694958)); - - tmp0 += z3; - tmp1 = z2 + z5; - tmp2 += z3; - tmp3 = z1 + z5; - } - } else { - if (d1) { - /* d1 != 0, d3 == 0, d5 == 0, d7 != 0 */ - z1 = d7 + d1; - z5 = MULTIPLY(z1, FIX(1.175875602)); - - z1 = MULTIPLY(z1, FIX(0.275899379)); - z3 = MULTIPLY(d7, - FIX(1.961570560)); - tmp0 = MULTIPLY(d7, - FIX(1.662939224)); - z4 = MULTIPLY(d1, - FIX(0.390180644)); - tmp3 = MULTIPLY(d1, FIX(1.111140466)); - - tmp0 += z1; - tmp1 = z4 + z5; - tmp2 = z3 + z5; - tmp3 += z1; - } else { - /* d1 == 0, d3 == 0, d5 == 0, d7 != 0 */ - tmp0 = MULTIPLY(d7, - FIX(1.387039845)); - tmp1 = MULTIPLY(d7, FIX(1.175875602)); - tmp2 = MULTIPLY(d7, - FIX(0.785694958)); - tmp3 = MULTIPLY(d7, FIX(0.275899379)); - } - } - } - } else { - if (d5) { - if (d3) { - if (d1) { - /* d1 != 0, d3 != 0, d5 != 0, d7 == 0 */ - z2 = d5 + d3; - z4 = d5 + d1; - z5 = MULTIPLY(d3 + z4, FIX(1.175875602)); - - tmp1 = MULTIPLY(d5, FIX(2.053119869)); - tmp2 = MULTIPLY(d3, FIX(3.072711026)); - tmp3 = MULTIPLY(d1, FIX(1.501321110)); - z1 = MULTIPLY(d1, - FIX(0.899976223)); - z2 = MULTIPLY(z2, - FIX(2.562915447)); - z3 = MULTIPLY(d3, - FIX(1.961570560)); - z4 = MULTIPLY(z4, - FIX(0.390180644)); - - z3 += z5; - z4 += z5; - - tmp0 = z1 + z3; - tmp1 += z2 + z4; - tmp2 += z2 + z3; - tmp3 += z1 + z4; - } else { - /* d1 == 0, d3 != 0, d5 != 0, d7 == 0 */ - z2 = d5 + d3; - - z5 = MULTIPLY(z2, FIX(1.175875602)); - tmp1 = MULTIPLY(d5, FIX(1.662939225)); - z4 = MULTIPLY(d5, - FIX(0.390180644)); - z2 = MULTIPLY(z2, - FIX(1.387039845)); - tmp2 = MULTIPLY(d3, FIX(1.111140466)); - z3 = MULTIPLY(d3, - FIX(1.961570560)); - - tmp0 = z3 + z5; - tmp1 += z2; - tmp2 += z2; - tmp3 = z4 + z5; - } - } else { - if (d1) { - /* d1 != 0, d3 == 0, d5 != 0, d7 == 0 */ - z4 = d5 + d1; - - z5 = MULTIPLY(z4, FIX(1.175875602)); - z1 = MULTIPLY(d1, - FIX(0.899976223)); - tmp3 = MULTIPLY(d1, FIX(0.601344887)); - tmp1 = MULTIPLY(d5, - FIX(0.509795578)); - z2 = MULTIPLY(d5, - FIX(2.562915447)); - z4 = MULTIPLY(z4, FIX(0.785694958)); - - tmp0 = z1 + z5; - tmp1 += z4; - tmp2 = z2 + z5; - tmp3 += z4; - } else { - /* d1 == 0, d3 == 0, d5 != 0, d7 == 0 */ - tmp0 = MULTIPLY(d5, FIX(1.175875602)); - tmp1 = MULTIPLY(d5, FIX(0.275899380)); - tmp2 = MULTIPLY(d5, - FIX(1.387039845)); - tmp3 = MULTIPLY(d5, FIX(0.785694958)); - } - } - } else { - if (d3) { - if (d1) { - /* d1 != 0, d3 != 0, d5 == 0, d7 == 0 */ - z5 = d1 + d3; - tmp3 = MULTIPLY(d1, FIX(0.211164243)); - tmp2 = MULTIPLY(d3, - FIX(1.451774981)); - z1 = MULTIPLY(d1, FIX(1.061594337)); - z2 = MULTIPLY(d3, - FIX(2.172734803)); - z4 = MULTIPLY(z5, FIX(0.785694958)); - z5 = MULTIPLY(z5, FIX(1.175875602)); - - tmp0 = z1 - z4; - tmp1 = z2 + z4; - tmp2 += z5; - tmp3 += z5; - } else { - /* d1 == 0, d3 != 0, d5 == 0, d7 == 0 */ - tmp0 = MULTIPLY(d3, - FIX(0.785694958)); - tmp1 = MULTIPLY(d3, - FIX(1.387039845)); - tmp2 = MULTIPLY(d3, - FIX(0.275899379)); - tmp3 = MULTIPLY(d3, FIX(1.175875602)); - } - } else { - if (d1) { - /* d1 != 0, d3 == 0, d5 == 0, d7 == 0 */ - tmp0 = MULTIPLY(d1, FIX(0.275899379)); - tmp1 = MULTIPLY(d1, FIX(0.785694958)); - tmp2 = MULTIPLY(d1, FIX(1.175875602)); - tmp3 = MULTIPLY(d1, FIX(1.387039845)); - } else { - /* d1 == 0, d3 == 0, d5 == 0, d7 == 0 */ - tmp0 = tmp1 = tmp2 = tmp3 = 0; - } - } - } - } - - /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */ - - dataptr[0] = (DCTELEM) DESCALE(tmp10 + tmp3, CONST_BITS-PASS1_BITS); - dataptr[7] = (DCTELEM) DESCALE(tmp10 - tmp3, CONST_BITS-PASS1_BITS); - dataptr[1] = (DCTELEM) DESCALE(tmp11 + tmp2, CONST_BITS-PASS1_BITS); - dataptr[6] = (DCTELEM) DESCALE(tmp11 - tmp2, CONST_BITS-PASS1_BITS); - dataptr[2] = (DCTELEM) DESCALE(tmp12 + tmp1, CONST_BITS-PASS1_BITS); - dataptr[5] = (DCTELEM) DESCALE(tmp12 - tmp1, CONST_BITS-PASS1_BITS); - dataptr[3] = (DCTELEM) DESCALE(tmp13 + tmp0, CONST_BITS-PASS1_BITS); - dataptr[4] = (DCTELEM) DESCALE(tmp13 - tmp0, CONST_BITS-PASS1_BITS); - - dataptr += DCTSIZE; /* advance pointer to next row */ - } - - /* Pass 2: process columns. */ - /* Note that we must descale the results by a factor of 8 == 2**3, */ - /* and also undo the PASS1_BITS scaling. */ - - dataptr = data; - for (rowctr = DCTSIZE-1; rowctr >= 0; rowctr--) { - /* Columns of zeroes can be exploited in the same way as we did with rows. - * However, the row calculation has created many nonzero AC terms, so the - * simplification applies less often (typically 5% to 10% of the time). - * On machines with very fast multiplication, it's possible that the - * test takes more time than it's worth. In that case this section - * may be commented out. - */ - - d0 = dataptr[DCTSIZE*0]; - d1 = dataptr[DCTSIZE*1]; - d2 = dataptr[DCTSIZE*2]; - d3 = dataptr[DCTSIZE*3]; - d4 = dataptr[DCTSIZE*4]; - d5 = dataptr[DCTSIZE*5]; - d6 = dataptr[DCTSIZE*6]; - d7 = dataptr[DCTSIZE*7]; - - /* Even part: reverse the even part of the forward DCT. */ - /* The rotator is sqrt(2)*c(-6). */ - if (d6) { - if (d4) { - if (d2) { - if (d0) { - /* d0 != 0, d2 != 0, d4 != 0, d6 != 0 */ - z1 = MULTIPLY(d2 + d6, FIX(0.541196100)); - tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065)); - tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865)); - - tmp0 = (d0 + d4) << CONST_BITS; - tmp1 = (d0 - d4) << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp1 + tmp2; - tmp12 = tmp1 - tmp2; - } else { - /* d0 == 0, d2 != 0, d4 != 0, d6 != 0 */ - z1 = MULTIPLY(d2 + d6, FIX(0.541196100)); - tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065)); - tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865)); - - tmp0 = d4 << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp2 - tmp0; - tmp12 = -(tmp0 + tmp2); - } - } else { - if (d0) { - /* d0 != 0, d2 == 0, d4 != 0, d6 != 0 */ - tmp2 = MULTIPLY(d6, - FIX(1.306562965)); - tmp3 = MULTIPLY(d6, FIX(0.541196100)); - - tmp0 = (d0 + d4) << CONST_BITS; - tmp1 = (d0 - d4) << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp1 + tmp2; - tmp12 = tmp1 - tmp2; - } else { - /* d0 == 0, d2 == 0, d4 != 0, d6 != 0 */ - tmp2 = MULTIPLY(d6, -FIX(1.306562965)); - tmp3 = MULTIPLY(d6, FIX(0.541196100)); - - tmp0 = d4 << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp2 - tmp0; - tmp12 = -(tmp0 + tmp2); - } - } - } else { - if (d2) { - if (d0) { - /* d0 != 0, d2 != 0, d4 == 0, d6 != 0 */ - z1 = MULTIPLY(d2 + d6, FIX(0.541196100)); - tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065)); - tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865)); - - tmp0 = d0 << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp0 + tmp2; - tmp12 = tmp0 - tmp2; - } else { - /* d0 == 0, d2 != 0, d4 == 0, d6 != 0 */ - z1 = MULTIPLY(d2 + d6, FIX(0.541196100)); - tmp2 = z1 + MULTIPLY(d6, - FIX(1.847759065)); - tmp3 = z1 + MULTIPLY(d2, FIX(0.765366865)); - - tmp10 = tmp3; - tmp13 = -tmp3; - tmp11 = tmp2; - tmp12 = -tmp2; - } - } else { - if (d0) { - /* d0 != 0, d2 == 0, d4 == 0, d6 != 0 */ - tmp2 = MULTIPLY(d6, - FIX(1.306562965)); - tmp3 = MULTIPLY(d6, FIX(0.541196100)); - - tmp0 = d0 << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp0 + tmp2; - tmp12 = tmp0 - tmp2; - } else { - /* d0 == 0, d2 == 0, d4 == 0, d6 != 0 */ - tmp2 = MULTIPLY(d6, - FIX(1.306562965)); - tmp3 = MULTIPLY(d6, FIX(0.541196100)); - - tmp10 = tmp3; - tmp13 = -tmp3; - tmp11 = tmp2; - tmp12 = -tmp2; - } - } - } - } else { - if (d4) { - if (d2) { - if (d0) { - /* d0 != 0, d2 != 0, d4 != 0, d6 == 0 */ - tmp2 = MULTIPLY(d2, FIX(0.541196100)); - tmp3 = MULTIPLY(d2, FIX(1.306562965)); - - tmp0 = (d0 + d4) << CONST_BITS; - tmp1 = (d0 - d4) << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp1 + tmp2; - tmp12 = tmp1 - tmp2; - } else { - /* d0 == 0, d2 != 0, d4 != 0, d6 == 0 */ - tmp2 = MULTIPLY(d2, FIX(0.541196100)); - tmp3 = MULTIPLY(d2, FIX(1.306562965)); - - tmp0 = d4 << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp2 - tmp0; - tmp12 = -(tmp0 + tmp2); - } - } else { - if (d0) { - /* d0 != 0, d2 == 0, d4 != 0, d6 == 0 */ - tmp10 = tmp13 = (d0 + d4) << CONST_BITS; - tmp11 = tmp12 = (d0 - d4) << CONST_BITS; - } else { - /* d0 == 0, d2 == 0, d4 != 0, d6 == 0 */ - tmp10 = tmp13 = d4 << CONST_BITS; - tmp11 = tmp12 = -tmp10; - } - } - } else { - if (d2) { - if (d0) { - /* d0 != 0, d2 != 0, d4 == 0, d6 == 0 */ - tmp2 = MULTIPLY(d2, FIX(0.541196100)); - tmp3 = MULTIPLY(d2, FIX(1.306562965)); - - tmp0 = d0 << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp0 + tmp2; - tmp12 = tmp0 - tmp2; - } else { - /* d0 == 0, d2 != 0, d4 == 0, d6 == 0 */ - tmp2 = MULTIPLY(d2, FIX(0.541196100)); - tmp3 = MULTIPLY(d2, FIX(1.306562965)); - - tmp10 = tmp3; - tmp13 = -tmp3; - tmp11 = tmp2; - tmp12 = -tmp2; - } - } else { - if (d0) { - /* d0 != 0, d2 == 0, d4 == 0, d6 == 0 */ - tmp10 = tmp13 = tmp11 = tmp12 = d0 << CONST_BITS; - } else { - /* d0 == 0, d2 == 0, d4 == 0, d6 == 0 */ - tmp10 = tmp13 = tmp11 = tmp12 = 0; - } - } - } - } - - /* Odd part per figure 8; the matrix is unitary and hence its - * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively. - */ - if (d7) { - if (d5) { - if (d3) { - if (d1) { - /* d1 != 0, d3 != 0, d5 != 0, d7 != 0 */ - z1 = d7 + d1; - z2 = d5 + d3; - z3 = d7 + d3; - z4 = d5 + d1; - z5 = MULTIPLY(z3 + z4, FIX(1.175875602)); - - tmp0 = MULTIPLY(d7, FIX(0.298631336)); - tmp1 = MULTIPLY(d5, FIX(2.053119869)); - tmp2 = MULTIPLY(d3, FIX(3.072711026)); - tmp3 = MULTIPLY(d1, FIX(1.501321110)); - z1 = MULTIPLY(z1, - FIX(0.899976223)); - z2 = MULTIPLY(z2, - FIX(2.562915447)); - z3 = MULTIPLY(z3, - FIX(1.961570560)); - z4 = MULTIPLY(z4, - FIX(0.390180644)); - - z3 += z5; - z4 += z5; - - tmp0 += z1 + z3; - tmp1 += z2 + z4; - tmp2 += z2 + z3; - tmp3 += z1 + z4; - } else { - /* d1 == 0, d3 != 0, d5 != 0, d7 != 0 */ - z1 = d7; - z2 = d5 + d3; - z3 = d7 + d3; - z5 = MULTIPLY(z3 + d5, FIX(1.175875602)); - - tmp0 = MULTIPLY(d7, FIX(0.298631336)); - tmp1 = MULTIPLY(d5, FIX(2.053119869)); - tmp2 = MULTIPLY(d3, FIX(3.072711026)); - z1 = MULTIPLY(d7, - FIX(0.899976223)); - z2 = MULTIPLY(z2, - FIX(2.562915447)); - z3 = MULTIPLY(z3, - FIX(1.961570560)); - z4 = MULTIPLY(d5, - FIX(0.390180644)); - - z3 += z5; - z4 += z5; - - tmp0 += z1 + z3; - tmp1 += z2 + z4; - tmp2 += z2 + z3; - tmp3 = z1 + z4; - } - } else { - if (d1) { - /* d1 != 0, d3 == 0, d5 != 0, d7 != 0 */ - z1 = d7 + d1; - z2 = d5; - z3 = d7; - z4 = d5 + d1; - z5 = MULTIPLY(z3 + z4, FIX(1.175875602)); - - tmp0 = MULTIPLY(d7, FIX(0.298631336)); - tmp1 = MULTIPLY(d5, FIX(2.053119869)); - tmp3 = MULTIPLY(d1, FIX(1.501321110)); - z1 = MULTIPLY(z1, - FIX(0.899976223)); - z2 = MULTIPLY(d5, - FIX(2.562915447)); - z3 = MULTIPLY(d7, - FIX(1.961570560)); - z4 = MULTIPLY(z4, - FIX(0.390180644)); - - z3 += z5; - z4 += z5; - - tmp0 += z1 + z3; - tmp1 += z2 + z4; - tmp2 = z2 + z3; - tmp3 += z1 + z4; - } else { - /* d1 == 0, d3 == 0, d5 != 0, d7 != 0 */ - tmp0 = MULTIPLY(d7, - FIX(0.601344887)); - z1 = MULTIPLY(d7, - FIX(0.899976223)); - z3 = MULTIPLY(d7, - FIX(1.961570560)); - tmp1 = MULTIPLY(d5, - FIX(0.509795578)); - z2 = MULTIPLY(d5, - FIX(2.562915447)); - z4 = MULTIPLY(d5, - FIX(0.390180644)); - z5 = MULTIPLY(d5 + d7, FIX(1.175875602)); - - z3 += z5; - z4 += z5; - - tmp0 += z3; - tmp1 += z4; - tmp2 = z2 + z3; - tmp3 = z1 + z4; - } - } - } else { - if (d3) { - if (d1) { - /* d1 != 0, d3 != 0, d5 == 0, d7 != 0 */ - z1 = d7 + d1; - z3 = d7 + d3; - z5 = MULTIPLY(z3 + d1, FIX(1.175875602)); - - tmp0 = MULTIPLY(d7, FIX(0.298631336)); - tmp2 = MULTIPLY(d3, FIX(3.072711026)); - tmp3 = MULTIPLY(d1, FIX(1.501321110)); - z1 = MULTIPLY(z1, - FIX(0.899976223)); - z2 = MULTIPLY(d3, - FIX(2.562915447)); - z3 = MULTIPLY(z3, - FIX(1.961570560)); - z4 = MULTIPLY(d1, - FIX(0.390180644)); - - z3 += z5; - z4 += z5; - - tmp0 += z1 + z3; - tmp1 = z2 + z4; - tmp2 += z2 + z3; - tmp3 += z1 + z4; - } else { - /* d1 == 0, d3 != 0, d5 == 0, d7 != 0 */ - z3 = d7 + d3; - - tmp0 = MULTIPLY(d7, - FIX(0.601344887)); - z1 = MULTIPLY(d7, - FIX(0.899976223)); - tmp2 = MULTIPLY(d3, FIX(0.509795579)); - z2 = MULTIPLY(d3, - FIX(2.562915447)); - z5 = MULTIPLY(z3, FIX(1.175875602)); - z3 = MULTIPLY(z3, - FIX(0.785694958)); - - tmp0 += z3; - tmp1 = z2 + z5; - tmp2 += z3; - tmp3 = z1 + z5; - } - } else { - if (d1) { - /* d1 != 0, d3 == 0, d5 == 0, d7 != 0 */ - z1 = d7 + d1; - z5 = MULTIPLY(z1, FIX(1.175875602)); - - z1 = MULTIPLY(z1, FIX(0.275899379)); - z3 = MULTIPLY(d7, - FIX(1.961570560)); - tmp0 = MULTIPLY(d7, - FIX(1.662939224)); - z4 = MULTIPLY(d1, - FIX(0.390180644)); - tmp3 = MULTIPLY(d1, FIX(1.111140466)); - - tmp0 += z1; - tmp1 = z4 + z5; - tmp2 = z3 + z5; - tmp3 += z1; - } else { - /* d1 == 0, d3 == 0, d5 == 0, d7 != 0 */ - tmp0 = MULTIPLY(d7, - FIX(1.387039845)); - tmp1 = MULTIPLY(d7, FIX(1.175875602)); - tmp2 = MULTIPLY(d7, - FIX(0.785694958)); - tmp3 = MULTIPLY(d7, FIX(0.275899379)); - } - } - } - } else { - if (d5) { - if (d3) { - if (d1) { - /* d1 != 0, d3 != 0, d5 != 0, d7 == 0 */ - z2 = d5 + d3; - z4 = d5 + d1; - z5 = MULTIPLY(d3 + z4, FIX(1.175875602)); - - tmp1 = MULTIPLY(d5, FIX(2.053119869)); - tmp2 = MULTIPLY(d3, FIX(3.072711026)); - tmp3 = MULTIPLY(d1, FIX(1.501321110)); - z1 = MULTIPLY(d1, - FIX(0.899976223)); - z2 = MULTIPLY(z2, - FIX(2.562915447)); - z3 = MULTIPLY(d3, - FIX(1.961570560)); - z4 = MULTIPLY(z4, - FIX(0.390180644)); - - z3 += z5; - z4 += z5; - - tmp0 = z1 + z3; - tmp1 += z2 + z4; - tmp2 += z2 + z3; - tmp3 += z1 + z4; - } else { - /* d1 == 0, d3 != 0, d5 != 0, d7 == 0 */ - z2 = d5 + d3; - - z5 = MULTIPLY(z2, FIX(1.175875602)); - tmp1 = MULTIPLY(d5, FIX(1.662939225)); - z4 = MULTIPLY(d5, - FIX(0.390180644)); - z2 = MULTIPLY(z2, - FIX(1.387039845)); - tmp2 = MULTIPLY(d3, FIX(1.111140466)); - z3 = MULTIPLY(d3, - FIX(1.961570560)); - - tmp0 = z3 + z5; - tmp1 += z2; - tmp2 += z2; - tmp3 = z4 + z5; - } - } else { - if (d1) { - /* d1 != 0, d3 == 0, d5 != 0, d7 == 0 */ - z4 = d5 + d1; - - z5 = MULTIPLY(z4, FIX(1.175875602)); - z1 = MULTIPLY(d1, - FIX(0.899976223)); - tmp3 = MULTIPLY(d1, FIX(0.601344887)); - tmp1 = MULTIPLY(d5, - FIX(0.509795578)); - z2 = MULTIPLY(d5, - FIX(2.562915447)); - z4 = MULTIPLY(z4, FIX(0.785694958)); - - tmp0 = z1 + z5; - tmp1 += z4; - tmp2 = z2 + z5; - tmp3 += z4; - } else { - /* d1 == 0, d3 == 0, d5 != 0, d7 == 0 */ - tmp0 = MULTIPLY(d5, FIX(1.175875602)); - tmp1 = MULTIPLY(d5, FIX(0.275899380)); - tmp2 = MULTIPLY(d5, - FIX(1.387039845)); - tmp3 = MULTIPLY(d5, FIX(0.785694958)); - } - } - } else { - if (d3) { - if (d1) { - /* d1 != 0, d3 != 0, d5 == 0, d7 == 0 */ - z5 = d1 + d3; - tmp3 = MULTIPLY(d1, FIX(0.211164243)); - tmp2 = MULTIPLY(d3, - FIX(1.451774981)); - z1 = MULTIPLY(d1, FIX(1.061594337)); - z2 = MULTIPLY(d3, - FIX(2.172734803)); - z4 = MULTIPLY(z5, FIX(0.785694958)); - z5 = MULTIPLY(z5, FIX(1.175875602)); - - tmp0 = z1 - z4; - tmp1 = z2 + z4; - tmp2 += z5; - tmp3 += z5; - } else { - /* d1 == 0, d3 != 0, d5 == 0, d7 == 0 */ - tmp0 = MULTIPLY(d3, - FIX(0.785694958)); - tmp1 = MULTIPLY(d3, - FIX(1.387039845)); - tmp2 = MULTIPLY(d3, - FIX(0.275899379)); - tmp3 = MULTIPLY(d3, FIX(1.175875602)); - } - } else { - if (d1) { - /* d1 != 0, d3 == 0, d5 == 0, d7 == 0 */ - tmp0 = MULTIPLY(d1, FIX(0.275899379)); - tmp1 = MULTIPLY(d1, FIX(0.785694958)); - tmp2 = MULTIPLY(d1, FIX(1.175875602)); - tmp3 = MULTIPLY(d1, FIX(1.387039845)); - } else { - /* d1 == 0, d3 == 0, d5 == 0, d7 == 0 */ - tmp0 = tmp1 = tmp2 = tmp3 = 0; - } - } - } - } - - /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */ - - dataptr[DCTSIZE*0] = (DCTELEM) DESCALE(tmp10 + tmp3, - CONST_BITS+PASS1_BITS+3); - dataptr[DCTSIZE*7] = (DCTELEM) DESCALE(tmp10 - tmp3, - CONST_BITS+PASS1_BITS+3); - dataptr[DCTSIZE*1] = (DCTELEM) DESCALE(tmp11 + tmp2, - CONST_BITS+PASS1_BITS+3); - dataptr[DCTSIZE*6] = (DCTELEM) DESCALE(tmp11 - tmp2, - CONST_BITS+PASS1_BITS+3); - dataptr[DCTSIZE*2] = (DCTELEM) DESCALE(tmp12 + tmp1, - CONST_BITS+PASS1_BITS+3); - dataptr[DCTSIZE*5] = (DCTELEM) DESCALE(tmp12 - tmp1, - CONST_BITS+PASS1_BITS+3); - dataptr[DCTSIZE*3] = (DCTELEM) DESCALE(tmp13 + tmp0, - CONST_BITS+PASS1_BITS+3); - dataptr[DCTSIZE*4] = (DCTELEM) DESCALE(tmp13 - tmp0, - CONST_BITS+PASS1_BITS+3); - - dataptr++; /* advance pointer to next column */ - } -} - -#else - - -void -j_rev_dct_sparse (DCTBLOCK data, int pos) -{ - j_rev_dct(data); -} - -void -j_rev_dct (DCTBLOCK data) -{ - INT32 tmp0, tmp1, tmp2, tmp3; - INT32 tmp10, tmp11, tmp12, tmp13; - INT32 z1, z2, z3, z4, z5; - register DCTELEM *dataptr; - int rowctr; - SHIFT_TEMPS - - /* Pass 1: process rows. */ - /* Note results are scaled up by sqrt(8) compared to a true IDCT; */ - /* furthermore, we scale the results by 2**PASS1_BITS. */ - - dataptr = data; - for (rowctr = DCTSIZE-1; rowctr >= 0; rowctr--) { - /* Due to quantization, we will usually find that many of the input - * coefficients are zero, especially the AC terms. We can exploit this - * by short-circuiting the IDCT calculation for any row in which all - * the AC terms are zero. In that case each output is equal to the - * DC coefficient (with scale factor as needed). - * With typical images and quantization tables, half or more of the - * row DCT calculations can be simplified this way. - */ - - if ((dataptr[1] | dataptr[2] | dataptr[3] | dataptr[4] | - dataptr[5] | dataptr[6] | dataptr[7]) == 0) { - /* AC terms all zero */ - DCTELEM dcval = (DCTELEM) (dataptr[0] << PASS1_BITS); - - dataptr[0] = dcval; - dataptr[1] = dcval; - dataptr[2] = dcval; - dataptr[3] = dcval; - dataptr[4] = dcval; - dataptr[5] = dcval; - dataptr[6] = dcval; - dataptr[7] = dcval; - - dataptr += DCTSIZE; /* advance pointer to next row */ - continue; - } - - /* Even part: reverse the even part of the forward DCT. */ - /* The rotator is sqrt(2)*c(-6). */ - - z2 = (INT32) dataptr[2]; - z3 = (INT32) dataptr[6]; - - z1 = MULTIPLY(z2 + z3, FIX(0.541196100)); - tmp2 = z1 + MULTIPLY(z3, - FIX(1.847759065)); - tmp3 = z1 + MULTIPLY(z2, FIX(0.765366865)); - - tmp0 = ((INT32) dataptr[0] + (INT32) dataptr[4]) << CONST_BITS; - tmp1 = ((INT32) dataptr[0] - (INT32) dataptr[4]) << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp1 + tmp2; - tmp12 = tmp1 - tmp2; - - /* Odd part per figure 8; the matrix is unitary and hence its - * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively. - */ - - tmp0 = (INT32) dataptr[7]; - tmp1 = (INT32) dataptr[5]; - tmp2 = (INT32) dataptr[3]; - tmp3 = (INT32) dataptr[1]; - - z1 = tmp0 + tmp3; - z2 = tmp1 + tmp2; - z3 = tmp0 + tmp2; - z4 = tmp1 + tmp3; - z5 = MULTIPLY(z3 + z4, FIX(1.175875602)); /* sqrt(2) * c3 */ - - tmp0 = MULTIPLY(tmp0, FIX(0.298631336)); /* sqrt(2) * (-c1+c3+c5-c7) */ - tmp1 = MULTIPLY(tmp1, FIX(2.053119869)); /* sqrt(2) * ( c1+c3-c5+c7) */ - tmp2 = MULTIPLY(tmp2, FIX(3.072711026)); /* sqrt(2) * ( c1+c3+c5-c7) */ - tmp3 = MULTIPLY(tmp3, FIX(1.501321110)); /* sqrt(2) * ( c1+c3-c5-c7) */ - z1 = MULTIPLY(z1, - FIX(0.899976223)); /* sqrt(2) * (c7-c3) */ - z2 = MULTIPLY(z2, - FIX(2.562915447)); /* sqrt(2) * (-c1-c3) */ - z3 = MULTIPLY(z3, - FIX(1.961570560)); /* sqrt(2) * (-c3-c5) */ - z4 = MULTIPLY(z4, - FIX(0.390180644)); /* sqrt(2) * (c5-c3) */ - - z3 += z5; - z4 += z5; - - tmp0 += z1 + z3; - tmp1 += z2 + z4; - tmp2 += z2 + z3; - tmp3 += z1 + z4; - - /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */ - - dataptr[0] = (DCTELEM) DESCALE(tmp10 + tmp3, CONST_BITS-PASS1_BITS); - dataptr[7] = (DCTELEM) DESCALE(tmp10 - tmp3, CONST_BITS-PASS1_BITS); - dataptr[1] = (DCTELEM) DESCALE(tmp11 + tmp2, CONST_BITS-PASS1_BITS); - dataptr[6] = (DCTELEM) DESCALE(tmp11 - tmp2, CONST_BITS-PASS1_BITS); - dataptr[2] = (DCTELEM) DESCALE(tmp12 + tmp1, CONST_BITS-PASS1_BITS); - dataptr[5] = (DCTELEM) DESCALE(tmp12 - tmp1, CONST_BITS-PASS1_BITS); - dataptr[3] = (DCTELEM) DESCALE(tmp13 + tmp0, CONST_BITS-PASS1_BITS); - dataptr[4] = (DCTELEM) DESCALE(tmp13 - tmp0, CONST_BITS-PASS1_BITS); - - dataptr += DCTSIZE; /* advance pointer to next row */ - } - - /* Pass 2: process columns. */ - /* Note that we must descale the results by a factor of 8 == 2**3, */ - /* and also undo the PASS1_BITS scaling. */ - - dataptr = data; - for (rowctr = DCTSIZE-1; rowctr >= 0; rowctr--) { - /* Columns of zeroes can be exploited in the same way as we did with rows. - * However, the row calculation has created many nonzero AC terms, so the - * simplification applies less often (typically 5% to 10% of the time). - * On machines with very fast multiplication, it's possible that the - * test takes more time than it's worth. In that case this section - * may be commented out. - */ - -#ifndef NO_ZERO_COLUMN_TEST - if ((dataptr[DCTSIZE*1] | dataptr[DCTSIZE*2] | dataptr[DCTSIZE*3] | - dataptr[DCTSIZE*4] | dataptr[DCTSIZE*5] | dataptr[DCTSIZE*6] | - dataptr[DCTSIZE*7]) == 0) { - /* AC terms all zero */ - DCTELEM dcval = (DCTELEM) DESCALE((INT32) dataptr[0], PASS1_BITS+3); - - dataptr[DCTSIZE*0] = dcval; - dataptr[DCTSIZE*1] = dcval; - dataptr[DCTSIZE*2] = dcval; - dataptr[DCTSIZE*3] = dcval; - dataptr[DCTSIZE*4] = dcval; - dataptr[DCTSIZE*5] = dcval; - dataptr[DCTSIZE*6] = dcval; - dataptr[DCTSIZE*7] = dcval; - - dataptr++; /* advance pointer to next column */ - continue; - } -#endif - - /* Even part: reverse the even part of the forward DCT. */ - /* The rotator is sqrt(2)*c(-6). */ - - z2 = (INT32) dataptr[DCTSIZE*2]; - z3 = (INT32) dataptr[DCTSIZE*6]; - - z1 = MULTIPLY(z2 + z3, FIX(0.541196100)); - tmp2 = z1 + MULTIPLY(z3, - FIX(1.847759065)); - tmp3 = z1 + MULTIPLY(z2, FIX(0.765366865)); - - tmp0 = ((INT32) dataptr[DCTSIZE*0] + (INT32) dataptr[DCTSIZE*4]) << CONST_BITS; - tmp1 = ((INT32) dataptr[DCTSIZE*0] - (INT32) dataptr[DCTSIZE*4]) << CONST_BITS; - - tmp10 = tmp0 + tmp3; - tmp13 = tmp0 - tmp3; - tmp11 = tmp1 + tmp2; - tmp12 = tmp1 - tmp2; - - /* Odd part per figure 8; the matrix is unitary and hence its - * transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively. - */ - - tmp0 = (INT32) dataptr[DCTSIZE*7]; - tmp1 = (INT32) dataptr[DCTSIZE*5]; - tmp2 = (INT32) dataptr[DCTSIZE*3]; - tmp3 = (INT32) dataptr[DCTSIZE*1]; - - z1 = tmp0 + tmp3; - z2 = tmp1 + tmp2; - z3 = tmp0 + tmp2; - z4 = tmp1 + tmp3; - z5 = MULTIPLY(z3 + z4, FIX(1.175875602)); /* sqrt(2) * c3 */ - - tmp0 = MULTIPLY(tmp0, FIX(0.298631336)); /* sqrt(2) * (-c1+c3+c5-c7) */ - tmp1 = MULTIPLY(tmp1, FIX(2.053119869)); /* sqrt(2) * ( c1+c3-c5+c7) */ - tmp2 = MULTIPLY(tmp2, FIX(3.072711026)); /* sqrt(2) * ( c1+c3+c5-c7) */ - tmp3 = MULTIPLY(tmp3, FIX(1.501321110)); /* sqrt(2) * ( c1+c3-c5-c7) */ - z1 = MULTIPLY(z1, - FIX(0.899976223)); /* sqrt(2) * (c7-c3) */ - z2 = MULTIPLY(z2, - FIX(2.562915447)); /* sqrt(2) * (-c1-c3) */ - z3 = MULTIPLY(z3, - FIX(1.961570560)); /* sqrt(2) * (-c3-c5) */ - z4 = MULTIPLY(z4, - FIX(0.390180644)); /* sqrt(2) * (c5-c3) */ - - z3 += z5; - z4 += z5; - - tmp0 += z1 + z3; - tmp1 += z2 + z4; - tmp2 += z2 + z3; - tmp3 += z1 + z4; - - /* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */ - - dataptr[DCTSIZE*0] = (DCTELEM) DESCALE(tmp10 + tmp3, - CONST_BITS+PASS1_BITS+3); - dataptr[DCTSIZE*7] = (DCTELEM) DESCALE(tmp10 - tmp3, - CONST_BITS+PASS1_BITS+3); - dataptr[DCTSIZE*1] = (DCTELEM) DESCALE(tmp11 + tmp2, - CONST_BITS+PASS1_BITS+3); - dataptr[DCTSIZE*6] = (DCTELEM) DESCALE(tmp11 - tmp2, - CONST_BITS+PASS1_BITS+3); - dataptr[DCTSIZE*2] = (DCTELEM) DESCALE(tmp12 + tmp1, - CONST_BITS+PASS1_BITS+3); - dataptr[DCTSIZE*5] = (DCTELEM) DESCALE(tmp12 - tmp1, - CONST_BITS+PASS1_BITS+3); - dataptr[DCTSIZE*3] = (DCTELEM) DESCALE(tmp13 + tmp0, - CONST_BITS+PASS1_BITS+3); - dataptr[DCTSIZE*4] = (DCTELEM) DESCALE(tmp13 - tmp0, - CONST_BITS+PASS1_BITS+3); - - dataptr++; /* advance pointer to next column */ - } -} - - -#endif |