2 * Copyright (C) 2004 the ffmpeg project
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 * Standard C DSP-oriented functions cribbed from the original VP3
31 #define IdctAdjustBeforeShift 8
40 #define M(a,b) (((a) * (b))>>16)
42 static always_inline void idct(uint8_t *dst, int stride, int16_t *input, int type)
45 uint8_t *cm = cropTbl + MAX_NEG_CROP;
47 int A, B, C, D, Ad, Bd, Cd, Dd, E, F, G, H;
48 int Ed, Gd, Add, Bdd, Fd, Hd;
52 /* Inverse DCT on the rows now */
53 for (i = 0; i < 8; i++) {
54 /* Check for non-zero values */
55 if ( ip[0] | ip[1] | ip[2] | ip[3] | ip[4] | ip[5] | ip[6] | ip[7] ) {
56 A = M(xC1S7, ip[1]) + M(xC7S1, ip[7]);
57 B = M(xC7S1, ip[1]) - M(xC1S7, ip[7]);
58 C = M(xC3S5, ip[3]) + M(xC5S3, ip[5]);
59 D = M(xC3S5, ip[5]) - M(xC5S3, ip[3]);
61 Ad = M(xC4S4, (A - C));
62 Bd = M(xC4S4, (B - D));
67 E = M(xC4S4, (ip[0] + ip[4]));
68 F = M(xC4S4, (ip[0] - ip[4]));
70 G = M(xC2S6, ip[2]) + M(xC6S2, ip[6]);
71 H = M(xC6S2, ip[2]) - M(xC2S6, ip[6]);
82 /* Final sequence of operations over-write original inputs. */
96 ip += 8; /* next row */
101 for ( i = 0; i < 8; i++) {
102 /* Check for non-zero values (bitwise or faster than ||) */
103 if ( ip[1 * 8] | ip[2 * 8] | ip[3 * 8] |
104 ip[4 * 8] | ip[5 * 8] | ip[6 * 8] | ip[7 * 8] ) {
106 A = M(xC1S7, ip[1*8]) + M(xC7S1, ip[7*8]);
107 B = M(xC7S1, ip[1*8]) - M(xC1S7, ip[7*8]);
108 C = M(xC3S5, ip[3*8]) + M(xC5S3, ip[5*8]);
109 D = M(xC3S5, ip[5*8]) - M(xC5S3, ip[3*8]);
111 Ad = M(xC4S4, (A - C));
112 Bd = M(xC4S4, (B - D));
117 E = M(xC4S4, (ip[0*8] + ip[4*8])) + 8;
118 F = M(xC4S4, (ip[0*8] - ip[4*8])) + 8;
125 G = M(xC2S6, ip[2*8]) + M(xC6S2, ip[6*8]);
126 H = M(xC6S2, ip[2*8]) - M(xC2S6, ip[6*8]);
137 /* Final sequence of operations over-write original inputs. */
139 ip[0*8] = (Gd + Cd ) >> 4;
140 ip[7*8] = (Gd - Cd ) >> 4;
142 ip[1*8] = (Add + Hd ) >> 4;
143 ip[2*8] = (Add - Hd ) >> 4;
145 ip[3*8] = (Ed + Dd ) >> 4;
146 ip[4*8] = (Ed - Dd ) >> 4;
148 ip[5*8] = (Fd + Bdd ) >> 4;
149 ip[6*8] = (Fd - Bdd ) >> 4;
151 dst[0*stride] = cm[(Gd + Cd ) >> 4];
152 dst[7*stride] = cm[(Gd - Cd ) >> 4];
154 dst[1*stride] = cm[(Add + Hd ) >> 4];
155 dst[2*stride] = cm[(Add - Hd ) >> 4];
157 dst[3*stride] = cm[(Ed + Dd ) >> 4];
158 dst[4*stride] = cm[(Ed - Dd ) >> 4];
160 dst[5*stride] = cm[(Fd + Bdd ) >> 4];
161 dst[6*stride] = cm[(Fd - Bdd ) >> 4];
163 dst[0*stride] = cm[dst[0*stride] + ((Gd + Cd ) >> 4)];
164 dst[7*stride] = cm[dst[7*stride] + ((Gd - Cd ) >> 4)];
166 dst[1*stride] = cm[dst[1*stride] + ((Add + Hd ) >> 4)];
167 dst[2*stride] = cm[dst[2*stride] + ((Add - Hd ) >> 4)];
169 dst[3*stride] = cm[dst[3*stride] + ((Ed + Dd ) >> 4)];
170 dst[4*stride] = cm[dst[4*stride] + ((Ed - Dd ) >> 4)];
172 dst[5*stride] = cm[dst[5*stride] + ((Fd + Bdd ) >> 4)];
173 dst[6*stride] = cm[dst[6*stride] + ((Fd - Bdd ) >> 4)];
185 ip[7*8] = ((xC4S4 * ip[0*8] + (IdctAdjustBeforeShift<<16))>>20);
194 dst[7*stride]= 128 + ((xC4S4 * ip[0*8] + (IdctAdjustBeforeShift<<16))>>20);
197 int v= ((xC4S4 * ip[0*8] + (IdctAdjustBeforeShift<<16))>>20);
198 dst[0*stride] = cm[dst[0*stride] + v];
199 dst[1*stride] = cm[dst[1*stride] + v];
200 dst[2*stride] = cm[dst[2*stride] + v];
201 dst[3*stride] = cm[dst[3*stride] + v];
202 dst[4*stride] = cm[dst[4*stride] + v];
203 dst[5*stride] = cm[dst[5*stride] + v];
204 dst[6*stride] = cm[dst[6*stride] + v];
205 dst[7*stride] = cm[dst[7*stride] + v];
210 ip++; /* next column */
215 void ff_vp3_idct_c(DCTELEM *block/* align 16*/){
216 idct(NULL, 0, block, 0);
219 void ff_vp3_idct_put_c(uint8_t *dest/*align 8*/, int line_size, DCTELEM *block/*align 16*/){
220 idct(dest, line_size, block, 1);
223 void ff_vp3_idct_add_c(uint8_t *dest/*align 8*/, int line_size, DCTELEM *block/*align 16*/){
224 idct(dest, line_size, block, 2);