1/*
2 * Template for the Discrete Cosine Transform for 32 samples
3 * Copyright (c) 2001, 2002 Fabrice Bellard
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22#include "dct32.h"
23#include "mathops.h"
24#include "libavutil/internal.h"
25
26#ifdef CHECKED
27#define SUINT   int
28#define SUINT32 int32_t
29#else
30#define SUINT   unsigned
31#define SUINT32 uint32_t
32#endif
33
34#if DCT32_FLOAT
35#   define dct32 ff_dct32_float
36#   define FIXHR(x)       ((float)(x))
37#   define MULH3(x, y, s) ((s)*(y)*(x))
38#   define INTFLOAT float
39#   define SUINTFLOAT float
40#else
41#   define dct32 ff_dct32_fixed
42#   define FIXHR(a)       ((int)((a) * (1LL<<32) + 0.5))
43#   define MULH3(x, y, s) MULH((s)*(x), y)
44#   define INTFLOAT int
45#   define SUINTFLOAT SUINT
46#endif
47
48
49/* tab[i][j] = 1.0 / (2.0 * cos(pi*(2*k+1) / 2^(6 - j))) */
50
51/* cos(i*pi/64) */
52
53#define COS0_0  FIXHR(0.50060299823519630134/2)
54#define COS0_1  FIXHR(0.50547095989754365998/2)
55#define COS0_2  FIXHR(0.51544730992262454697/2)
56#define COS0_3  FIXHR(0.53104259108978417447/2)
57#define COS0_4  FIXHR(0.55310389603444452782/2)
58#define COS0_5  FIXHR(0.58293496820613387367/2)
59#define COS0_6  FIXHR(0.62250412303566481615/2)
60#define COS0_7  FIXHR(0.67480834145500574602/2)
61#define COS0_8  FIXHR(0.74453627100229844977/2)
62#define COS0_9  FIXHR(0.83934964541552703873/2)
63#define COS0_10 FIXHR(0.97256823786196069369/2)
64#define COS0_11 FIXHR(1.16943993343288495515/4)
65#define COS0_12 FIXHR(1.48416461631416627724/4)
66#define COS0_13 FIXHR(2.05778100995341155085/8)
67#define COS0_14 FIXHR(3.40760841846871878570/8)
68#define COS0_15 FIXHR(10.19000812354805681150/32)
69
70#define COS1_0 FIXHR(0.50241928618815570551/2)
71#define COS1_1 FIXHR(0.52249861493968888062/2)
72#define COS1_2 FIXHR(0.56694403481635770368/2)
73#define COS1_3 FIXHR(0.64682178335999012954/2)
74#define COS1_4 FIXHR(0.78815462345125022473/2)
75#define COS1_5 FIXHR(1.06067768599034747134/4)
76#define COS1_6 FIXHR(1.72244709823833392782/4)
77#define COS1_7 FIXHR(5.10114861868916385802/16)
78
79#define COS2_0 FIXHR(0.50979557910415916894/2)
80#define COS2_1 FIXHR(0.60134488693504528054/2)
81#define COS2_2 FIXHR(0.89997622313641570463/2)
82#define COS2_3 FIXHR(2.56291544774150617881/8)
83
84#define COS3_0 FIXHR(0.54119610014619698439/2)
85#define COS3_1 FIXHR(1.30656296487637652785/4)
86
87#define COS4_0 FIXHR(M_SQRT1_2/2)
88
89/* butterfly operator */
90#define BF(a, b, c, s)\
91{\
92    tmp0 = val##a + val##b;\
93    tmp1 = val##a - val##b;\
94    val##a = tmp0;\
95    val##b = MULH3(tmp1, c, 1<<(s));\
96}
97
98#define BF0(a, b, c, s)\
99{\
100    tmp0 = tab[a] + tab[b];\
101    tmp1 = tab[a] - tab[b];\
102    val##a = tmp0;\
103    val##b = MULH3(tmp1, c, 1<<(s));\
104}
105
106#define BF1(a, b, c, d)\
107{\
108    BF(a, b, COS4_0, 1);\
109    BF(c, d,-COS4_0, 1);\
110    val##c += val##d;\
111}
112
113#define BF2(a, b, c, d)\
114{\
115    BF(a, b, COS4_0, 1);\
116    BF(c, d,-COS4_0, 1);\
117    val##c += val##d;\
118    val##a += val##c;\
119    val##c += val##b;\
120    val##b += val##d;\
121}
122
123#define ADD(a, b) val##a += val##b
124
125/* DCT32 without 1/sqrt(2) coef zero scaling. */
126void dct32(INTFLOAT *out, const INTFLOAT *tab_arg)
127{
128    const SUINTFLOAT *tab = tab_arg;
129    SUINTFLOAT tmp0, tmp1;
130
131    SUINTFLOAT val0 , val1 , val2 , val3 , val4 , val5 , val6 , val7 ,
132             val8 , val9 , val10, val11, val12, val13, val14, val15,
133             val16, val17, val18, val19, val20, val21, val22, val23,
134             val24, val25, val26, val27, val28, val29, val30, val31;
135
136    /* pass 1 */
137    BF0( 0, 31, COS0_0 , 1);
138    BF0(15, 16, COS0_15, 5);
139    /* pass 2 */
140    BF( 0, 15, COS1_0 , 1);
141    BF(16, 31,-COS1_0 , 1);
142    /* pass 1 */
143    BF0( 7, 24, COS0_7 , 1);
144    BF0( 8, 23, COS0_8 , 1);
145    /* pass 2 */
146    BF( 7,  8, COS1_7 , 4);
147    BF(23, 24,-COS1_7 , 4);
148    /* pass 3 */
149    BF( 0,  7, COS2_0 , 1);
150    BF( 8, 15,-COS2_0 , 1);
151    BF(16, 23, COS2_0 , 1);
152    BF(24, 31,-COS2_0 , 1);
153    /* pass 1 */
154    BF0( 3, 28, COS0_3 , 1);
155    BF0(12, 19, COS0_12, 2);
156    /* pass 2 */
157    BF( 3, 12, COS1_3 , 1);
158    BF(19, 28,-COS1_3 , 1);
159    /* pass 1 */
160    BF0( 4, 27, COS0_4 , 1);
161    BF0(11, 20, COS0_11, 2);
162    /* pass 2 */
163    BF( 4, 11, COS1_4 , 1);
164    BF(20, 27,-COS1_4 , 1);
165    /* pass 3 */
166    BF( 3,  4, COS2_3 , 3);
167    BF(11, 12,-COS2_3 , 3);
168    BF(19, 20, COS2_3 , 3);
169    BF(27, 28,-COS2_3 , 3);
170    /* pass 4 */
171    BF( 0,  3, COS3_0 , 1);
172    BF( 4,  7,-COS3_0 , 1);
173    BF( 8, 11, COS3_0 , 1);
174    BF(12, 15,-COS3_0 , 1);
175    BF(16, 19, COS3_0 , 1);
176    BF(20, 23,-COS3_0 , 1);
177    BF(24, 27, COS3_0 , 1);
178    BF(28, 31,-COS3_0 , 1);
179
180
181
182    /* pass 1 */
183    BF0( 1, 30, COS0_1 , 1);
184    BF0(14, 17, COS0_14, 3);
185    /* pass 2 */
186    BF( 1, 14, COS1_1 , 1);
187    BF(17, 30,-COS1_1 , 1);
188    /* pass 1 */
189    BF0( 6, 25, COS0_6 , 1);
190    BF0( 9, 22, COS0_9 , 1);
191    /* pass 2 */
192    BF( 6,  9, COS1_6 , 2);
193    BF(22, 25,-COS1_6 , 2);
194    /* pass 3 */
195    BF( 1,  6, COS2_1 , 1);
196    BF( 9, 14,-COS2_1 , 1);
197    BF(17, 22, COS2_1 , 1);
198    BF(25, 30,-COS2_1 , 1);
199
200    /* pass 1 */
201    BF0( 2, 29, COS0_2 , 1);
202    BF0(13, 18, COS0_13, 3);
203    /* pass 2 */
204    BF( 2, 13, COS1_2 , 1);
205    BF(18, 29,-COS1_2 , 1);
206    /* pass 1 */
207    BF0( 5, 26, COS0_5 , 1);
208    BF0(10, 21, COS0_10, 1);
209    /* pass 2 */
210    BF( 5, 10, COS1_5 , 2);
211    BF(21, 26,-COS1_5 , 2);
212    /* pass 3 */
213    BF( 2,  5, COS2_2 , 1);
214    BF(10, 13,-COS2_2 , 1);
215    BF(18, 21, COS2_2 , 1);
216    BF(26, 29,-COS2_2 , 1);
217    /* pass 4 */
218    BF( 1,  2, COS3_1 , 2);
219    BF( 5,  6,-COS3_1 , 2);
220    BF( 9, 10, COS3_1 , 2);
221    BF(13, 14,-COS3_1 , 2);
222    BF(17, 18, COS3_1 , 2);
223    BF(21, 22,-COS3_1 , 2);
224    BF(25, 26, COS3_1 , 2);
225    BF(29, 30,-COS3_1 , 2);
226
227    /* pass 5 */
228    BF1( 0,  1,  2,  3);
229    BF2( 4,  5,  6,  7);
230    BF1( 8,  9, 10, 11);
231    BF2(12, 13, 14, 15);
232    BF1(16, 17, 18, 19);
233    BF2(20, 21, 22, 23);
234    BF1(24, 25, 26, 27);
235    BF2(28, 29, 30, 31);
236
237    /* pass 6 */
238
239    ADD( 8, 12);
240    ADD(12, 10);
241    ADD(10, 14);
242    ADD(14,  9);
243    ADD( 9, 13);
244    ADD(13, 11);
245    ADD(11, 15);
246
247    out[ 0] = val0;
248    out[16] = val1;
249    out[ 8] = val2;
250    out[24] = val3;
251    out[ 4] = val4;
252    out[20] = val5;
253    out[12] = val6;
254    out[28] = val7;
255    out[ 2] = val8;
256    out[18] = val9;
257    out[10] = val10;
258    out[26] = val11;
259    out[ 6] = val12;
260    out[22] = val13;
261    out[14] = val14;
262    out[30] = val15;
263
264    ADD(24, 28);
265    ADD(28, 26);
266    ADD(26, 30);
267    ADD(30, 25);
268    ADD(25, 29);
269    ADD(29, 27);
270    ADD(27, 31);
271
272    out[ 1] = val16 + val24;
273    out[17] = val17 + val25;
274    out[ 9] = val18 + val26;
275    out[25] = val19 + val27;
276    out[ 5] = val20 + val28;
277    out[21] = val21 + val29;
278    out[13] = val22 + val30;
279    out[29] = val23 + val31;
280    out[ 3] = val24 + val20;
281    out[19] = val25 + val21;
282    out[11] = val26 + val22;
283    out[27] = val27 + val23;
284    out[ 7] = val28 + val18;
285    out[23] = val29 + val19;
286    out[15] = val30 + val17;
287    out[31] = val31;
288}
289