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author | Björn Stenberg <bjorn@haxx.se> | 2007-01-08 23:53:00 +0000 |
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committer | Björn Stenberg <bjorn@haxx.se> | 2007-01-08 23:53:00 +0000 |
commit | 7039a05147b8bbfc829babea1c65bd436450b505 (patch) | |
tree | 4ba555eb84ed97b72b0575034d5b0530a393713e /songdbj/com/jcraft/jorbis/Mdct.java | |
parent | 6d4c19707ef95942e323cbdc89fbbfdbe45e7cc5 (diff) | |
download | rockbox-7039a05147b8bbfc829babea1c65bd436450b505.tar.gz rockbox-7039a05147b8bbfc829babea1c65bd436450b505.zip |
Splitting out songdbj
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@11953 a1c6a512-1295-4272-9138-f99709370657
Diffstat (limited to 'songdbj/com/jcraft/jorbis/Mdct.java')
-rw-r--r-- | songdbj/com/jcraft/jorbis/Mdct.java | 249 |
1 files changed, 0 insertions, 249 deletions
diff --git a/songdbj/com/jcraft/jorbis/Mdct.java b/songdbj/com/jcraft/jorbis/Mdct.java deleted file mode 100644 index bd5cc38fb7..0000000000 --- a/songdbj/com/jcraft/jorbis/Mdct.java +++ /dev/null | |||
@@ -1,249 +0,0 @@ | |||
1 | /* JOrbis | ||
2 | * Copyright (C) 2000 ymnk, JCraft,Inc. | ||
3 | * | ||
4 | * Written by: 2000 ymnk<ymnk@jcraft.com> | ||
5 | * | ||
6 | * Many thanks to | ||
7 | * Monty <monty@xiph.org> and | ||
8 | * The XIPHOPHORUS Company http://www.xiph.org/ . | ||
9 | * JOrbis has been based on their awesome works, Vorbis codec. | ||
10 | * | ||
11 | * This program is free software; you can redistribute it and/or | ||
12 | * modify it under the terms of the GNU Library General Public License | ||
13 | * as published by the Free Software Foundation; either version 2 of | ||
14 | * the License, or (at your option) any later version. | ||
15 | |||
16 | * This program is distributed in the hope that it will be useful, | ||
17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
19 | * GNU Library General Public License for more details. | ||
20 | * | ||
21 | * You should have received a copy of the GNU Library General Public | ||
22 | * License along with this program; if not, write to the Free Software | ||
23 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | ||
24 | */ | ||
25 | |||
26 | package com.jcraft.jorbis; | ||
27 | |||
28 | class Mdct{ | ||
29 | |||
30 | static private final float cPI3_8=0.38268343236508977175f; | ||
31 | static private final float cPI2_8=0.70710678118654752441f; | ||
32 | static private final float cPI1_8=0.92387953251128675613f; | ||
33 | |||
34 | int n; | ||
35 | int log2n; | ||
36 | |||
37 | float[] trig; | ||
38 | int[] bitrev; | ||
39 | |||
40 | float scale; | ||
41 | |||
42 | void init(int n){ | ||
43 | bitrev=new int[n/4]; | ||
44 | trig=new float[n+n/4]; | ||
45 | |||
46 | int n2=n>>>1; | ||
47 | log2n=(int)Math.rint(Math.log(n)/Math.log(2)); | ||
48 | this.n=n; | ||
49 | |||
50 | |||
51 | int AE=0; | ||
52 | int AO=1; | ||
53 | int BE=AE+n/2; | ||
54 | int BO=BE+1; | ||
55 | int CE=BE+n/2; | ||
56 | int CO=CE+1; | ||
57 | // trig lookups... | ||
58 | for(int i=0;i<n/4;i++){ | ||
59 | trig[AE+i*2]=(float)Math.cos((Math.PI/n)*(4*i)); | ||
60 | trig[AO+i*2]=(float)-Math.sin((Math.PI/n)*(4*i)); | ||
61 | trig[BE+i*2]=(float)Math.cos((Math.PI/(2*n))*(2*i+1)); | ||
62 | trig[BO+i*2]=(float)Math.sin((Math.PI/(2*n))*(2*i+1)); | ||
63 | } | ||
64 | for(int i=0;i<n/8;i++){ | ||
65 | trig[CE+i*2]=(float)Math.cos((Math.PI/n)*(4*i+2)); | ||
66 | trig[CO+i*2]=(float)-Math.sin((Math.PI/n)*(4*i+2)); | ||
67 | } | ||
68 | |||
69 | { | ||
70 | int mask=(1<<(log2n-1))-1; | ||
71 | int msb=1<<(log2n-2); | ||
72 | for(int i=0;i<n/8;i++){ | ||
73 | int acc=0; | ||
74 | for(int j=0;msb>>>j!=0;j++) | ||
75 | if(((msb>>>j)&i)!=0)acc|=1<<j; | ||
76 | bitrev[i*2]=((~acc)&mask); | ||
77 | // bitrev[i*2]=((~acc)&mask)-1; | ||
78 | bitrev[i*2+1]=acc; | ||
79 | } | ||
80 | } | ||
81 | scale=4.f/n; | ||
82 | } | ||
83 | |||
84 | void clear(){ | ||
85 | } | ||
86 | |||
87 | void forward(float[] in, float[] out){ | ||
88 | } | ||
89 | |||
90 | float[] _x=new float[1024]; | ||
91 | float[] _w=new float[1024]; | ||
92 | |||
93 | synchronized void backward(float[] in, float[] out){ | ||
94 | if(_x.length<n/2){_x=new float[n/2];} | ||
95 | if(_w.length<n/2){_w=new float[n/2];} | ||
96 | float[] x=_x; | ||
97 | float[] w=_w; | ||
98 | int n2=n>>>1; | ||
99 | int n4=n>>>2; | ||
100 | int n8=n>>>3; | ||
101 | |||
102 | // rotate + step 1 | ||
103 | { | ||
104 | int inO=1; | ||
105 | int xO=0; | ||
106 | int A=n2; | ||
107 | |||
108 | int i; | ||
109 | for(i=0;i<n8;i++){ | ||
110 | A-=2; | ||
111 | x[xO++]=-in[inO+2]*trig[A+1] - in[inO]*trig[A]; | ||
112 | x[xO++]= in[inO]*trig[A+1] - in[inO+2]*trig[A]; | ||
113 | inO+=4; | ||
114 | } | ||
115 | |||
116 | inO=n2-4; | ||
117 | |||
118 | for(i=0;i<n8;i++){ | ||
119 | A-=2; | ||
120 | x[xO++]=in[inO]*trig[A+1] + in[inO+2]*trig[A]; | ||
121 | x[xO++]=in[inO]*trig[A] - in[inO+2]*trig[A+1]; | ||
122 | inO-=4; | ||
123 | } | ||
124 | } | ||
125 | |||
126 | float[] xxx=mdct_kernel(x,w,n,n2,n4,n8); | ||
127 | int xx=0; | ||
128 | |||
129 | // step 8 | ||
130 | |||
131 | { | ||
132 | int B=n2; | ||
133 | int o1=n4,o2=o1-1; | ||
134 | int o3=n4+n2,o4=o3-1; | ||
135 | |||
136 | for(int i=0;i<n4;i++){ | ||
137 | float temp1= (xxx[xx] * trig[B+1] - xxx[xx+1] * trig[B]); | ||
138 | float temp2=-(xxx[xx] * trig[B] + xxx[xx+1] * trig[B+1]); | ||
139 | |||
140 | out[o1]=-temp1; | ||
141 | out[o2]= temp1; | ||
142 | out[o3]= temp2; | ||
143 | out[o4]= temp2; | ||
144 | |||
145 | o1++; | ||
146 | o2--; | ||
147 | o3++; | ||
148 | o4--; | ||
149 | xx+=2; | ||
150 | B+=2; | ||
151 | } | ||
152 | } | ||
153 | } | ||
154 | private float[] mdct_kernel(float[] x, float[] w, | ||
155 | int n, int n2, int n4, int n8){ | ||
156 | // step 2 | ||
157 | |||
158 | int xA=n4; | ||
159 | int xB=0; | ||
160 | int w2=n4; | ||
161 | int A=n2; | ||
162 | |||
163 | for(int i=0;i<n4;){ | ||
164 | float x0=x[xA] - x[xB]; | ||
165 | float x1; | ||
166 | w[w2+i]=x[xA++]+x[xB++]; | ||
167 | |||
168 | x1=x[xA]-x[xB]; | ||
169 | A-=4; | ||
170 | |||
171 | w[i++]= x0 * trig[A] + x1 * trig[A+1]; | ||
172 | w[i]= x1 * trig[A] - x0 * trig[A+1]; | ||
173 | |||
174 | w[w2+i]=x[xA++]+x[xB++]; | ||
175 | i++; | ||
176 | } | ||
177 | |||
178 | // step 3 | ||
179 | |||
180 | { | ||
181 | for(int i=0;i<log2n-3;i++){ | ||
182 | int k0=n>>>(i+2); | ||
183 | int k1=1<<(i+3); | ||
184 | int wbase=n2-2; | ||
185 | |||
186 | A=0; | ||
187 | float[] temp; | ||
188 | |||
189 | for(int r=0;r<(k0>>>2);r++){ | ||
190 | int w1=wbase; | ||
191 | w2=w1-(k0>>1); | ||
192 | float AEv= trig[A],wA; | ||
193 | float AOv= trig[A+1],wB; | ||
194 | wbase-=2; | ||
195 | |||
196 | k0++; | ||
197 | for(int s=0;s<(2<<i);s++){ | ||
198 | wB =w[w1] -w[w2]; | ||
199 | x[w1] =w[w1] +w[w2]; | ||
200 | |||
201 | wA =w[++w1] -w[++w2]; | ||
202 | x[w1] =w[w1] +w[w2]; | ||
203 | |||
204 | x[w2] =wA*AEv - wB*AOv; | ||
205 | x[w2-1]=wB*AEv + wA*AOv; | ||
206 | |||
207 | w1-=k0; | ||
208 | w2-=k0; | ||
209 | } | ||
210 | k0--; | ||
211 | A+=k1; | ||
212 | } | ||
213 | |||
214 | temp=w; | ||
215 | w=x; | ||
216 | x=temp; | ||
217 | } | ||
218 | } | ||
219 | |||
220 | // step 4, 5, 6, 7 | ||
221 | { | ||
222 | int C=n; | ||
223 | int bit=0; | ||
224 | int x1=0; | ||
225 | int x2=n2-1; | ||
226 | |||
227 | for(int i=0;i<n8;i++){ | ||
228 | int t1=bitrev[bit++]; | ||
229 | int t2=bitrev[bit++]; | ||
230 | |||
231 | float wA=w[t1]-w[t2+1]; | ||
232 | float wB=w[t1-1]+w[t2]; | ||
233 | float wC=w[t1]+w[t2+1]; | ||
234 | float wD=w[t1-1]-w[t2]; | ||
235 | |||
236 | float wACE=wA* trig[C]; | ||
237 | float wBCE=wB* trig[C++]; | ||
238 | float wACO=wA* trig[C]; | ||
239 | float wBCO=wB* trig[C++]; | ||
240 | |||
241 | x[x1++]=( wC+wACO+wBCE)*.5f; | ||
242 | x[x2--]=(-wD+wBCO-wACE)*.5f; | ||
243 | x[x1++]=( wD+wBCO-wACE)*.5f; | ||
244 | x[x2--]=( wC-wACO-wBCE)*.5f; | ||
245 | } | ||
246 | } | ||
247 | return(x); | ||
248 | } | ||
249 | } | ||