Imported Debian version 2.5.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavcodec / simple_idct.c
CommitLineData
2ba45a60
DM
1/*
2 * Simple IDCT
3 *
4 * Copyright (c) 2001 Michael Niedermayer <michaelni@gmx.at>
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23/**
24 * @file
25 * simpleidct in C.
26 */
27
28#include "libavutil/intreadwrite.h"
29#include "avcodec.h"
30#include "mathops.h"
31#include "simple_idct.h"
32
33#define BIT_DEPTH 8
34#include "simple_idct_template.c"
35#undef BIT_DEPTH
36
37#define BIT_DEPTH 10
38#include "simple_idct_template.c"
39#undef BIT_DEPTH
40
41#define BIT_DEPTH 12
42#include "simple_idct_template.c"
43#undef BIT_DEPTH
44
45/* 2x4x8 idct */
46
47#define CN_SHIFT 12
48#define C_FIX(x) ((int)((x) * (1 << CN_SHIFT) + 0.5))
49#define C1 C_FIX(0.6532814824)
50#define C2 C_FIX(0.2705980501)
51
52/* row idct is multiple by 16 * sqrt(2.0), col idct4 is normalized,
53 and the butterfly must be multiplied by 0.5 * sqrt(2.0) */
54#define C_SHIFT (4+1+12)
55
56static inline void idct4col_put(uint8_t *dest, int line_size, const int16_t *col)
57{
58 int c0, c1, c2, c3, a0, a1, a2, a3;
59
60 a0 = col[8*0];
61 a1 = col[8*2];
62 a2 = col[8*4];
63 a3 = col[8*6];
64 c0 = ((a0 + a2) << (CN_SHIFT - 1)) + (1 << (C_SHIFT - 1));
65 c2 = ((a0 - a2) << (CN_SHIFT - 1)) + (1 << (C_SHIFT - 1));
66 c1 = a1 * C1 + a3 * C2;
67 c3 = a1 * C2 - a3 * C1;
68 dest[0] = av_clip_uint8((c0 + c1) >> C_SHIFT);
69 dest += line_size;
70 dest[0] = av_clip_uint8((c2 + c3) >> C_SHIFT);
71 dest += line_size;
72 dest[0] = av_clip_uint8((c2 - c3) >> C_SHIFT);
73 dest += line_size;
74 dest[0] = av_clip_uint8((c0 - c1) >> C_SHIFT);
75}
76
77#define BF(k) \
78{\
79 int a0, a1;\
80 a0 = ptr[k];\
81 a1 = ptr[8 + k];\
82 ptr[k] = a0 + a1;\
83 ptr[8 + k] = a0 - a1;\
84}
85
86/* only used by DV codec. The input must be interlaced. 128 is added
87 to the pixels before clamping to avoid systematic error
88 (1024*sqrt(2)) offset would be needed otherwise. */
89/* XXX: I think a 1.0/sqrt(2) normalization should be needed to
90 compensate the extra butterfly stage - I don't have the full DV
91 specification */
92void ff_simple_idct248_put(uint8_t *dest, int line_size, int16_t *block)
93{
94 int i;
95 int16_t *ptr;
96
97 /* butterfly */
98 ptr = block;
99 for(i=0;i<4;i++) {
100 BF(0);
101 BF(1);
102 BF(2);
103 BF(3);
104 BF(4);
105 BF(5);
106 BF(6);
107 BF(7);
108 ptr += 2 * 8;
109 }
110
111 /* IDCT8 on each line */
112 for(i=0; i<8; i++) {
113 idctRowCondDC_8(block + i*8, 0);
114 }
115
116 /* IDCT4 and store */
117 for(i=0;i<8;i++) {
118 idct4col_put(dest + i, 2 * line_size, block + i);
119 idct4col_put(dest + line_size + i, 2 * line_size, block + 8 + i);
120 }
121}
122
123/* 8x4 & 4x8 WMV2 IDCT */
124#undef CN_SHIFT
125#undef C_SHIFT
126#undef C_FIX
127#undef C1
128#undef C2
129#define CN_SHIFT 12
130#define C_FIX(x) ((int)((x) * 1.414213562 * (1 << CN_SHIFT) + 0.5))
131#define C1 C_FIX(0.6532814824)
132#define C2 C_FIX(0.2705980501)
133#define C3 C_FIX(0.5)
134#define C_SHIFT (4+1+12)
135static inline void idct4col_add(uint8_t *dest, int line_size, const int16_t *col)
136{
137 int c0, c1, c2, c3, a0, a1, a2, a3;
138
139 a0 = col[8*0];
140 a1 = col[8*1];
141 a2 = col[8*2];
142 a3 = col[8*3];
143 c0 = (a0 + a2)*C3 + (1 << (C_SHIFT - 1));
144 c2 = (a0 - a2)*C3 + (1 << (C_SHIFT - 1));
145 c1 = a1 * C1 + a3 * C2;
146 c3 = a1 * C2 - a3 * C1;
147 dest[0] = av_clip_uint8(dest[0] + ((c0 + c1) >> C_SHIFT));
148 dest += line_size;
149 dest[0] = av_clip_uint8(dest[0] + ((c2 + c3) >> C_SHIFT));
150 dest += line_size;
151 dest[0] = av_clip_uint8(dest[0] + ((c2 - c3) >> C_SHIFT));
152 dest += line_size;
153 dest[0] = av_clip_uint8(dest[0] + ((c0 - c1) >> C_SHIFT));
154}
155
156#define RN_SHIFT 15
157#define R_FIX(x) ((int)((x) * 1.414213562 * (1 << RN_SHIFT) + 0.5))
158#define R1 R_FIX(0.6532814824)
159#define R2 R_FIX(0.2705980501)
160#define R3 R_FIX(0.5)
161#define R_SHIFT 11
162static inline void idct4row(int16_t *row)
163{
164 int c0, c1, c2, c3, a0, a1, a2, a3;
165
166 a0 = row[0];
167 a1 = row[1];
168 a2 = row[2];
169 a3 = row[3];
170 c0 = (a0 + a2)*R3 + (1 << (R_SHIFT - 1));
171 c2 = (a0 - a2)*R3 + (1 << (R_SHIFT - 1));
172 c1 = a1 * R1 + a3 * R2;
173 c3 = a1 * R2 - a3 * R1;
174 row[0]= (c0 + c1) >> R_SHIFT;
175 row[1]= (c2 + c3) >> R_SHIFT;
176 row[2]= (c2 - c3) >> R_SHIFT;
177 row[3]= (c0 - c1) >> R_SHIFT;
178}
179
180void ff_simple_idct84_add(uint8_t *dest, int line_size, int16_t *block)
181{
182 int i;
183
184 /* IDCT8 on each line */
185 for(i=0; i<4; i++) {
186 idctRowCondDC_8(block + i*8, 0);
187 }
188
189 /* IDCT4 and store */
190 for(i=0;i<8;i++) {
191 idct4col_add(dest + i, line_size, block + i);
192 }
193}
194
195void ff_simple_idct48_add(uint8_t *dest, int line_size, int16_t *block)
196{
197 int i;
198
199 /* IDCT4 on each line */
200 for(i=0; i<8; i++) {
201 idct4row(block + i*8);
202 }
203
204 /* IDCT8 and store */
205 for(i=0; i<4; i++){
206 idctSparseColAdd_8(dest + i, line_size, block + i);
207 }
208}
209
210void ff_simple_idct44_add(uint8_t *dest, int line_size, int16_t *block)
211{
212 int i;
213
214 /* IDCT4 on each line */
215 for(i=0; i<4; i++) {
216 idct4row(block + i*8);
217 }
218
219 /* IDCT4 and store */
220 for(i=0; i<4; i++){
221 idct4col_add(dest + i, line_size, block + i);
222 }
223}
224
225void ff_prores_idct(int16_t *block, const int16_t *qmat)
226{
227 int i;
228
229 for (i = 0; i < 64; i++)
230 block[i] *= qmat[i];
231
232 for (i = 0; i < 8; i++)
233 idctRowCondDC_10(block + i*8, 2);
234
235 for (i = 0; i < 8; i++) {
236 block[i] += 8192;
237 idctSparseCol_10(block + i);
238 }
239}