1 /* -----------------------------------------------------------------------------
2 Software License for The Fraunhofer FDK AAC Codec Library for Android
3
4 © Copyright 1995 - 2018 Fraunhofer-Gesellschaft zur Förderung der angewandten
5 Forschung e.V. All rights reserved.
6
7 1. INTRODUCTION
8 The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software
9 that implements the MPEG Advanced Audio Coding ("AAC") encoding and decoding
10 scheme for digital audio. This FDK AAC Codec software is intended to be used on
11 a wide variety of Android devices.
12
13 AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient
14 general perceptual audio codecs. AAC-ELD is considered the best-performing
15 full-bandwidth communications codec by independent studies and is widely
16 deployed. AAC has been standardized by ISO and IEC as part of the MPEG
17 specifications.
18
19 Patent licenses for necessary patent claims for the FDK AAC Codec (including
20 those of Fraunhofer) may be obtained through Via Licensing
21 (www.vialicensing.com) or through the respective patent owners individually for
22 the purpose of encoding or decoding bit streams in products that are compliant
23 with the ISO/IEC MPEG audio standards. Please note that most manufacturers of
24 Android devices already license these patent claims through Via Licensing or
25 directly from the patent owners, and therefore FDK AAC Codec software may
26 already be covered under those patent licenses when it is used for those
27 licensed purposes only.
28
29 Commercially-licensed AAC software libraries, including floating-point versions
30 with enhanced sound quality, are also available from Fraunhofer. Users are
31 encouraged to check the Fraunhofer website for additional applications
32 information and documentation.
33
34 2. COPYRIGHT LICENSE
35
36 Redistribution and use in source and binary forms, with or without modification,
37 are permitted without payment of copyright license fees provided that you
38 satisfy the following conditions:
39
40 You must retain the complete text of this software license in redistributions of
41 the FDK AAC Codec or your modifications thereto in source code form.
42
43 You must retain the complete text of this software license in the documentation
44 and/or other materials provided with redistributions of the FDK AAC Codec or
45 your modifications thereto in binary form. You must make available free of
46 charge copies of the complete source code of the FDK AAC Codec and your
47 modifications thereto to recipients of copies in binary form.
48
49 The name of Fraunhofer may not be used to endorse or promote products derived
50 from this library without prior written permission.
51
52 You may not charge copyright license fees for anyone to use, copy or distribute
53 the FDK AAC Codec software or your modifications thereto.
54
55 Your modified versions of the FDK AAC Codec must carry prominent notices stating
56 that you changed the software and the date of any change. For modified versions
57 of the FDK AAC Codec, the term "Fraunhofer FDK AAC Codec Library for Android"
58 must be replaced by the term "Third-Party Modified Version of the Fraunhofer FDK
59 AAC Codec Library for Android."
60
61 3. NO PATENT LICENSE
62
63 NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without
64 limitation the patents of Fraunhofer, ARE GRANTED BY THIS SOFTWARE LICENSE.
65 Fraunhofer provides no warranty of patent non-infringement with respect to this
66 software.
67
68 You may use this FDK AAC Codec software or modifications thereto only for
69 purposes that are authorized by appropriate patent licenses.
70
71 4. DISCLAIMER
72
73 This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright
74 holders and contributors "AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES,
75 including but not limited to the implied warranties of merchantability and
76 fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
77 CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary,
78 or consequential damages, including but not limited to procurement of substitute
79 goods or services; loss of use, data, or profits, or business interruption,
80 however caused and on any theory of liability, whether in contract, strict
81 liability, or tort (including negligence), arising in any way out of the use of
82 this software, even if advised of the possibility of such damage.
83
84 5. CONTACT INFORMATION
85
86 Fraunhofer Institute for Integrated Circuits IIS
87 Attention: Audio and Multimedia Departments - FDK AAC LL
88 Am Wolfsmantel 33
89 91058 Erlangen, Germany
90
91 www.iis.fraunhofer.de/amm
92 amm-info@iis.fraunhofer.de
93 ----------------------------------------------------------------------------- */
94
95 /**************************** AAC decoder library ******************************
96
97 Author(s): Matthias Hildenbrand
98
99 Description: USAC ACELP LTP filter
100
101 *******************************************************************************/
102
103 #include "usacdec_ace_ltp.h"
104
105 #include "genericStds.h"
106 #include "common_fix.h"
107
108 #define UP_SAMP 4
109 #define L_INTERPOL2 16
110 #define L_SUBFR 64
111
112 #define A2 FL2FX_SGL(2 * 0.18f)
113 #define B FL2FX_SGL(0.64f)
114
115 static const LONG Pred_lt4_inter4_2[UP_SAMP][L_INTERPOL2] = {
116 {(LONG)0x0000FFFC, (LONG)0x0008FFFC, (LONG)0xFFEB004C, (LONG)0xFF50014A,
117 (LONG)0xFDD90351, (LONG)0xFB2A06CD, (LONG)0xF6920D46, (LONG)0xEBB42B35,
118 (LONG)0x6D9EEF39, (LONG)0x0618FE0F, (LONG)0xFFE00131, (LONG)0xFE5501C5,
119 (LONG)0xFE5E015D, (LONG)0xFEF700B6, (LONG)0xFF920037, (LONG)0xFFEC0003},
120 {(LONG)0x0002FFF2, (LONG)0x0026FFBD, (LONG)0x005DFF98, (LONG)0x0055FFEF,
121 (LONG)0xFF89015F, (LONG)0xFD3A04E5, (LONG)0xF7D90DAA, (LONG)0xE67A50EE,
122 (LONG)0x50EEE67A, (LONG)0x0DAAF7D9, (LONG)0x04E5FD3A, (LONG)0x015FFF89,
123 (LONG)0xFFEF0055, (LONG)0xFF98005D, (LONG)0xFFBD0026, (LONG)0xFFF20002},
124 {(LONG)0x0003FFEC, (LONG)0x0037FF92, (LONG)0x00B6FEF7, (LONG)0x015DFE5E,
125 (LONG)0x01C5FE55, (LONG)0x0131FFE0, (LONG)0xFE0F0618, (LONG)0xEF396D9E,
126 (LONG)0x2B35EBB4, (LONG)0x0D46F692, (LONG)0x06CDFB2A, (LONG)0x0351FDD9,
127 (LONG)0x014AFF50, (LONG)0x004CFFEB, (LONG)0xFFFC0008, (LONG)0xFFFC0000},
128 {(LONG)0x0002FFF2, (LONG)0x002BFF9E, (LONG)0x00B9FECE, (LONG)0x01CFFD75,
129 (LONG)0x035EFBC1, (LONG)0x0521FA0C, (LONG)0x06AAF8C9, (LONG)0x07907852,
130 (LONG)0x0790F8C9, (LONG)0x06AAFA0C, (LONG)0x0521FBC1, (LONG)0x035EFD75,
131 (LONG)0x01CFFECE, (LONG)0x00B9FF9E, (LONG)0x002BFFF2, (LONG)0x00020000}};
132
Pred_lt4(FIXP_DBL exc[],int T0,int frac)133 void Pred_lt4(FIXP_DBL exc[], /* in/out: excitation buffer */
134 int T0, /* input : integer pitch lag */
135 int frac /* input : fraction of lag in range 0..3 */
136 ) {
137 int j;
138 FIXP_DBL *x;
139 const LONG *interpol;
140 FIXP_DBL L_sumb, L_sumt;
141
142 x = &exc[-T0 - L_INTERPOL2 + 1];
143
144 /* remap frac and x:
145 0 -> 3 x (unchanged)
146 1 -> 0 x--
147 2 -> 1 x--
148 3 -> 2 x--
149 */
150
151 if (--frac < 0)
152 frac += UP_SAMP;
153 else
154 x--;
155
156 j = L_SUBFR + 1;
157 do {
158 LONG filt;
159 FIXP_DBL x0, x1;
160 FIXP_DBL *xi = x++;
161 interpol = Pred_lt4_inter4_2[frac];
162 int i = 3;
163
164 filt = *interpol++;
165 x0 = *xi++;
166 x1 = *xi++;
167 L_sumt = fMultDiv2(x0, (FIXP_SGL)((SHORT)(filt >> 16)));
168 L_sumb = fMultDiv2(x1, (FIXP_SGL)((SHORT)filt));
169 do {
170 filt = *interpol++;
171 x0 = *xi++;
172 x1 = *xi++;
173 L_sumt = fMultAddDiv2(L_sumt, x0, (FIXP_SGL)((SHORT)(filt >> 16)));
174 L_sumb = fMultAddDiv2(L_sumb, x1, (FIXP_SGL)((SHORT)filt));
175
176 filt = *interpol++;
177 x0 = *xi++;
178 x1 = *xi++;
179 L_sumt = fMultAddDiv2(L_sumt, x0, (FIXP_SGL)((SHORT)(filt >> 16)));
180 L_sumb = fMultAddDiv2(L_sumb, x1, (FIXP_SGL)((SHORT)filt));
181
182 filt = *interpol++;
183 x0 = *xi++;
184 x1 = *xi++;
185 L_sumt = fMultAddDiv2(L_sumt, x0, (FIXP_SGL)((SHORT)(filt >> 16)));
186 L_sumb = fMultAddDiv2(L_sumb, x1, (FIXP_SGL)((SHORT)filt));
187
188 filt = *interpol++;
189 x0 = *xi++;
190 x1 = *xi++;
191 L_sumt = fMultAddDiv2(L_sumt, x0, (FIXP_SGL)((SHORT)(filt >> 16)));
192 L_sumb = fMultAddDiv2(L_sumb, x1, (FIXP_SGL)((SHORT)filt));
193
194 filt = *interpol++;
195 x0 = *xi++;
196 x1 = *xi++;
197 L_sumt = fMultAddDiv2(L_sumt, x0, (FIXP_SGL)((SHORT)(filt >> 16)));
198 L_sumb = fMultAddDiv2(L_sumb, x1, (FIXP_SGL)((SHORT)filt));
199 } while (--i != 0);
200
201 L_sumb <<= 1;
202 L_sumb = fAddSaturate(L_sumt << 1, L_sumb);
203 *exc++ = L_sumb;
204 } while (--j != 0);
205 return;
206 }
207
Pred_lt4_postfilter(FIXP_DBL exc[])208 void Pred_lt4_postfilter(FIXP_DBL exc[] /* in/out: excitation buffer */
209 ) {
210 /*
211 exc[i] = A*exc[i-1] + B*exc[i] + A*exc[i+1]
212 exc[i+1] = A*exc[i] + B*exc[i+1] + A*exc[i+2] ; i = 0:2:62
213 */
214 int i;
215 FIXP_DBL sum0, sum1, a_exc0, a_exc1;
216 a_exc0 = fMultDiv2(A2, exc[-1]);
217 a_exc1 = fMultDiv2(A2, exc[0]);
218
219 /* ARM926: 22 cycles/iteration */
220 for (i = 0; i < L_SUBFR; i += 2) {
221 sum0 = a_exc0 + fMult(B, exc[i]);
222 sum1 = a_exc1 + fMult(B, exc[i + 1]);
223 a_exc0 = fMultDiv2(A2, exc[i + 1]);
224 a_exc1 = fMultDiv2(A2, exc[i + 2]);
225 exc[i] = sum0 + a_exc0;
226 exc[i + 1] = sum1 + a_exc1;
227 }
228 return;
229 }
230