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author | Sean Bartell <wingedtachikoma@gmail.com> | 2011-06-25 21:32:25 -0400 |
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committer | Nils Wallménius <nils@rockbox.org> | 2012-04-25 22:13:20 +0200 |
commit | f40bfc9267b13b54e6379dfe7539447662879d24 (patch) | |
tree | 9b20069d5e62809ff434061ad730096836f916f2 /lib/rbcodec/codecs/libwmavoice/dct.c | |
parent | a0009907de7a0107d49040d8a180f140e2eff299 (diff) | |
download | rockbox-f40bfc9267b13b54e6379dfe7539447662879d24.tar.gz rockbox-f40bfc9267b13b54e6379dfe7539447662879d24.zip |
Add codecs to librbcodec.
Change-Id: Id7f4717d51ed02d67cb9f9cb3c0ada4a81843f97
Reviewed-on: http://gerrit.rockbox.org/137
Reviewed-by: Nils Wallménius <nils@rockbox.org>
Tested-by: Nils Wallménius <nils@rockbox.org>
Diffstat (limited to 'lib/rbcodec/codecs/libwmavoice/dct.c')
-rw-r--r-- | lib/rbcodec/codecs/libwmavoice/dct.c | 226 |
1 files changed, 226 insertions, 0 deletions
diff --git a/lib/rbcodec/codecs/libwmavoice/dct.c b/lib/rbcodec/codecs/libwmavoice/dct.c new file mode 100644 index 0000000000..95aef5af6c --- /dev/null +++ b/lib/rbcodec/codecs/libwmavoice/dct.c | |||
@@ -0,0 +1,226 @@ | |||
1 | /* | ||
2 | * (I)DCT Transforms | ||
3 | * Copyright (c) 2009 Peter Ross <pross@xvid.org> | ||
4 | * Copyright (c) 2010 Alex Converse <alex.converse@gmail.com> | ||
5 | * Copyright (c) 2010 Vitor Sessak | ||
6 | * | ||
7 | * This file is part of FFmpeg. | ||
8 | * | ||
9 | * FFmpeg is free software; you can redistribute it and/or | ||
10 | * modify it under the terms of the GNU Lesser General Public | ||
11 | * License as published by the Free Software Foundation; either | ||
12 | * version 2.1 of the License, or (at your option) any later version. | ||
13 | * | ||
14 | * FFmpeg is distributed in the hope that it will be useful, | ||
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
17 | * Lesser General Public License for more details. | ||
18 | * | ||
19 | * You should have received a copy of the GNU Lesser General Public | ||
20 | * License along with FFmpeg; if not, write to the Free Software | ||
21 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | ||
22 | */ | ||
23 | |||
24 | /** | ||
25 | * @file | ||
26 | * (Inverse) Discrete Cosine Transforms. These are also known as the | ||
27 | * type II and type III DCTs respectively. | ||
28 | */ | ||
29 | |||
30 | #include <math.h> | ||
31 | #include "libavutil/mathematics.h" | ||
32 | #include "fft.h" | ||
33 | //#include "x86/fft.h" | ||
34 | |||
35 | #define DCT32_FLOAT | ||
36 | #include "dct32.c" | ||
37 | |||
38 | /* sin((M_PI * x / (2*n)) */ | ||
39 | #define SIN(s,n,x) (s->costab[(n) - (x)]) | ||
40 | |||
41 | /* cos((M_PI * x / (2*n)) */ | ||
42 | #define COS(s,n,x) (s->costab[x]) | ||
43 | |||
44 | static void ff_dst_calc_I_c(DCTContext *ctx, FFTSample *data) | ||
45 | { | ||
46 | int n = 1 << ctx->nbits; | ||
47 | int i; | ||
48 | |||
49 | data[0] = 0; | ||
50 | for(i = 1; i < n/2; i++) { | ||
51 | float tmp1 = data[i ]; | ||
52 | float tmp2 = data[n - i]; | ||
53 | float s = SIN(ctx, n, 2*i); | ||
54 | |||
55 | s *= tmp1 + tmp2; | ||
56 | tmp1 = (tmp1 - tmp2) * 0.5f; | ||
57 | data[i ] = s + tmp1; | ||
58 | data[n - i] = s - tmp1; | ||
59 | } | ||
60 | |||
61 | data[n/2] *= 2; | ||
62 | ff_rdft_calc(&ctx->rdft, data); | ||
63 | |||
64 | data[0] *= 0.5f; | ||
65 | |||
66 | for(i = 1; i < n-2; i += 2) { | ||
67 | data[i + 1] += data[i - 1]; | ||
68 | data[i ] = -data[i + 2]; | ||
69 | } | ||
70 | |||
71 | data[n-1] = 0; | ||
72 | } | ||
73 | |||
74 | static void ff_dct_calc_I_c(DCTContext *ctx, FFTSample *data) | ||
75 | { | ||
76 | int n = 1 << ctx->nbits; | ||
77 | int i; | ||
78 | float next = -0.5f * (data[0] - data[n]); | ||
79 | |||
80 | for(i = 0; i < n/2; i++) { | ||
81 | float tmp1 = data[i ]; | ||
82 | float tmp2 = data[n - i]; | ||
83 | float s = SIN(ctx, n, 2*i); | ||
84 | float c = COS(ctx, n, 2*i); | ||
85 | |||
86 | c *= tmp1 - tmp2; | ||
87 | s *= tmp1 - tmp2; | ||
88 | |||
89 | next += c; | ||
90 | |||
91 | tmp1 = (tmp1 + tmp2) * 0.5f; | ||
92 | data[i ] = tmp1 - s; | ||
93 | data[n - i] = tmp1 + s; | ||
94 | } | ||
95 | |||
96 | ff_rdft_calc(&ctx->rdft, data); | ||
97 | data[n] = data[1]; | ||
98 | data[1] = next; | ||
99 | |||
100 | for(i = 3; i <= n; i += 2) | ||
101 | data[i] = data[i - 2] - data[i]; | ||
102 | } | ||
103 | |||
104 | static void ff_dct_calc_III_c(DCTContext *ctx, FFTSample *data) | ||
105 | { | ||
106 | int n = 1 << ctx->nbits; | ||
107 | int i; | ||
108 | |||
109 | float next = data[n - 1]; | ||
110 | float inv_n = 1.0f / n; | ||
111 | |||
112 | for (i = n - 2; i >= 2; i -= 2) { | ||
113 | float val1 = data[i ]; | ||
114 | float val2 = data[i - 1] - data[i + 1]; | ||
115 | float c = COS(ctx, n, i); | ||
116 | float s = SIN(ctx, n, i); | ||
117 | |||
118 | data[i ] = c * val1 + s * val2; | ||
119 | data[i + 1] = s * val1 - c * val2; | ||
120 | } | ||
121 | |||
122 | data[1] = 2 * next; | ||
123 | |||
124 | ff_rdft_calc(&ctx->rdft, data); | ||
125 | |||
126 | for (i = 0; i < n / 2; i++) { | ||
127 | float tmp1 = data[i ] * inv_n; | ||
128 | float tmp2 = data[n - i - 1] * inv_n; | ||
129 | float csc = ctx->csc2[i] * (tmp1 - tmp2); | ||
130 | |||
131 | tmp1 += tmp2; | ||
132 | data[i ] = tmp1 + csc; | ||
133 | data[n - i - 1] = tmp1 - csc; | ||
134 | } | ||
135 | } | ||
136 | |||
137 | static void ff_dct_calc_II_c(DCTContext *ctx, FFTSample *data) | ||
138 | { | ||
139 | int n = 1 << ctx->nbits; | ||
140 | int i; | ||
141 | float next; | ||
142 | |||
143 | for (i=0; i < n/2; i++) { | ||
144 | float tmp1 = data[i ]; | ||
145 | float tmp2 = data[n - i - 1]; | ||
146 | float s = SIN(ctx, n, 2*i + 1); | ||
147 | |||
148 | s *= tmp1 - tmp2; | ||
149 | tmp1 = (tmp1 + tmp2) * 0.5f; | ||
150 | |||
151 | data[i ] = tmp1 + s; | ||
152 | data[n-i-1] = tmp1 - s; | ||
153 | } | ||
154 | |||
155 | ff_rdft_calc(&ctx->rdft, data); | ||
156 | |||
157 | next = data[1] * 0.5; | ||
158 | data[1] *= -1; | ||
159 | |||
160 | for (i = n - 2; i >= 0; i -= 2) { | ||
161 | float inr = data[i ]; | ||
162 | float ini = data[i + 1]; | ||
163 | float c = COS(ctx, n, i); | ||
164 | float s = SIN(ctx, n, i); | ||
165 | |||
166 | data[i ] = c * inr + s * ini; | ||
167 | |||
168 | data[i+1] = next; | ||
169 | |||
170 | next += s * inr - c * ini; | ||
171 | } | ||
172 | } | ||
173 | |||
174 | static void dct32_func(DCTContext *ctx, FFTSample *data) | ||
175 | { | ||
176 | ctx->dct32(data, data); | ||
177 | } | ||
178 | |||
179 | void ff_dct_calc(DCTContext *s, FFTSample *data) | ||
180 | { | ||
181 | s->dct_calc(s, data); | ||
182 | } | ||
183 | |||
184 | av_cold int ff_dct_init(DCTContext *s, int nbits, enum DCTTransformType inverse) | ||
185 | { | ||
186 | int n = 1 << nbits; | ||
187 | int i; | ||
188 | |||
189 | s->nbits = nbits; | ||
190 | s->inverse = inverse; | ||
191 | |||
192 | ff_init_ff_cos_tabs(nbits+2); | ||
193 | |||
194 | s->costab = ff_cos_tabs[nbits+2]; | ||
195 | |||
196 | s->csc2 = av_malloc(n/2 * sizeof(FFTSample)); | ||
197 | |||
198 | if (ff_rdft_init(&s->rdft, nbits, inverse == DCT_III) < 0) { | ||
199 | av_free(s->csc2); | ||
200 | return -1; | ||
201 | } | ||
202 | |||
203 | for (i = 0; i < n/2; i++) | ||
204 | s->csc2[i] = 0.5 / sin((M_PI / (2*n) * (2*i + 1))); | ||
205 | |||
206 | switch(inverse) { | ||
207 | case DCT_I : s->dct_calc = ff_dct_calc_I_c; break; | ||
208 | case DCT_II : s->dct_calc = ff_dct_calc_II_c ; break; | ||
209 | case DCT_III: s->dct_calc = ff_dct_calc_III_c; break; | ||
210 | case DST_I : s->dct_calc = ff_dst_calc_I_c; break; | ||
211 | } | ||
212 | |||
213 | if (inverse == DCT_II && nbits == 5) | ||
214 | s->dct_calc = dct32_func; | ||
215 | |||
216 | s->dct32 = dct32; | ||
217 | //if (HAVE_MMX) ff_dct_init_mmx(s); | ||
218 | |||
219 | return 0; | ||
220 | } | ||
221 | |||
222 | av_cold void ff_dct_end(DCTContext *s) | ||
223 | { | ||
224 | ff_rdft_end(&s->rdft); | ||
225 | av_free(s->csc2); | ||
226 | } | ||