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 /*********************** MPEG surround decoder library *************************
96
97 Author(s): Matthias Hildenbrand
98
99 Description: USAC MPS212 Transient Steering Decorrelator (TSD)
100
101 *******************************************************************************/
102
103 #include "sac_tsd.h"
104
105 #define TSD_START_BAND (7)
106 #define SIZE_S (4)
107 #define SIZE_C (5)
108
109 /*** Tables ***/
110 RAM_ALIGN
111 LNK_SECTION_CONSTDATA
112 static const UCHAR nBitsTsdCW_32slots[32] = {
113 5, 9, 13, 16, 18, 20, 22, 24, 25, 26, 27, 28, 29, 29, 30, 30,
114 30, 29, 29, 28, 27, 26, 25, 24, 22, 20, 18, 16, 13, 9, 5, 0};
115
116 RAM_ALIGN
117 LNK_SECTION_CONSTDATA
118 static const UCHAR nBitsTsdCW_64slots[64] = {
119 6, 11, 16, 20, 23, 27, 30, 33, 35, 38, 40, 42, 44, 46, 48, 49,
120 51, 52, 53, 55, 56, 57, 58, 58, 59, 60, 60, 60, 61, 61, 61, 61,
121 61, 61, 61, 60, 60, 60, 59, 58, 58, 57, 56, 55, 53, 52, 51, 49,
122 48, 46, 44, 42, 40, 38, 35, 33, 30, 27, 23, 20, 16, 11, 6, 0};
123
124 RAM_ALIGN
125 LNK_SECTION_CONSTDATA
126 static const FIXP_STP phiTsd[8] = {
127 STCP(0x7fffffff, 0x00000000), STCP(0x5a82799a, 0x5a82799a),
128 STCP(0x00000000, 0x7fffffff), STCP(0xa57d8666, 0x5a82799a),
129 STCP(0x80000000, 0x00000000), STCP(0xa57d8666, 0xa57d8666),
130 STCP(0x00000000, 0x80000000), STCP(0x5a82799a, 0xa57d8666),
131 };
132
133 /*** Static Functions ***/
longmult1(USHORT a[],USHORT b,USHORT d[],int len)134 static void longmult1(USHORT a[], USHORT b, USHORT d[], int len) {
135 int k;
136 ULONG tmp;
137 ULONG b0 = (ULONG)b;
138
139 tmp = ((ULONG)a[0]) * b0;
140 d[0] = (USHORT)tmp;
141
142 for (k = 1; k < len; k++) {
143 tmp = (tmp >> 16) + ((ULONG)a[k]) * b0;
144 d[k] = (USHORT)tmp;
145 }
146 }
147
longdiv(USHORT b[],USHORT a,USHORT d[],USHORT * pr,int len)148 static void longdiv(USHORT b[], USHORT a, USHORT d[], USHORT *pr, int len) {
149 ULONG r;
150 ULONG tmp;
151 int k;
152
153 FDK_ASSERT(a != 0);
154
155 r = 0;
156
157 for (k = len - 1; k >= 0; k--) {
158 tmp = ((ULONG)b[k]) + (r << 16);
159
160 if (tmp) {
161 d[k] = (USHORT)(tmp / a);
162 r = tmp - d[k] * a;
163 } else {
164 d[k] = 0;
165 }
166 }
167 *pr = (USHORT)r;
168 }
169
longsub(USHORT a[],USHORT b[],int lena,int lenb)170 static void longsub(USHORT a[], USHORT b[], int lena, int lenb) {
171 int h;
172 LONG carry = 0;
173
174 FDK_ASSERT(lena >= lenb);
175 for (h = 0; h < lenb; h++) {
176 carry += ((LONG)a[h]) - ((LONG)b[h]);
177 a[h] = (USHORT)carry;
178 carry = carry >> 16;
179 }
180
181 for (; h < lena; h++) {
182 carry = ((LONG)a[h]) + carry;
183 a[h] = (USHORT)carry;
184 carry = carry >> 16;
185 }
186
187 FDK_ASSERT(carry ==
188 0); /* carry != 0 indicates subtraction underflow, e.g. b > a */
189 return;
190 }
191
longcompare(USHORT a[],USHORT b[],int len)192 static int longcompare(USHORT a[], USHORT b[], int len) {
193 int i;
194
195 for (i = len - 1; i > 0; i--) {
196 if (a[i] != b[i]) break;
197 }
198 return (a[i] >= b[i]) ? 1 : 0;
199 }
200
isTrSlot(const TSD_DATA * pTsdData,const int ts)201 FDK_INLINE int isTrSlot(const TSD_DATA *pTsdData, const int ts) {
202 return (pTsdData->bsTsdTrPhaseData[ts] >= 0);
203 }
204
205 /*** Public Functions ***/
TsdRead(HANDLE_FDK_BITSTREAM hBs,const int numSlots,TSD_DATA * pTsdData)206 int TsdRead(HANDLE_FDK_BITSTREAM hBs, const int numSlots, TSD_DATA *pTsdData) {
207 int nBitsTrSlots = 0;
208 int bsTsdNumTrSlots;
209 const UCHAR *nBitsTsdCW_tab = NULL;
210
211 switch (numSlots) {
212 case 32:
213 nBitsTrSlots = 4;
214 nBitsTsdCW_tab = nBitsTsdCW_32slots;
215 break;
216 case 64:
217 nBitsTrSlots = 5;
218 nBitsTsdCW_tab = nBitsTsdCW_64slots;
219 break;
220 default:
221 return 1;
222 }
223
224 /*** Read TempShapeData for bsTempShapeConfig == 3 ***/
225 pTsdData->bsTsdEnable = FDKreadBit(hBs);
226 if (!pTsdData->bsTsdEnable) {
227 return 0;
228 }
229
230 /*** Parse/Decode TsdData() ***/
231 pTsdData->numSlots = numSlots;
232
233 bsTsdNumTrSlots = FDKreadBits(hBs, nBitsTrSlots);
234
235 /* Decode transient slot positions */
236 {
237 int nBitsTsdCW = (int)nBitsTsdCW_tab[bsTsdNumTrSlots];
238 SCHAR *phaseData = pTsdData->bsTsdTrPhaseData;
239 int p = bsTsdNumTrSlots + 1;
240 int k, h;
241 USHORT s[SIZE_S] = {0};
242 USHORT c[SIZE_C] = {0};
243 USHORT r[1];
244
245 /* Init with TsdSepData[k] = 0 */
246 for (k = 0; k < numSlots; k++) {
247 phaseData[k] = -1; /* means TsdSepData[] = 0 */
248 }
249
250 for (h = (SIZE_S - 1); h >= 0; h--) {
251 if (nBitsTsdCW > h * 16) {
252 s[h] = (USHORT)FDKreadBits(hBs, nBitsTsdCW - h * 16);
253 nBitsTsdCW = h * 16;
254 }
255 }
256
257 /* c = prod_{h=1}^{p} (k-p+h)/h */
258 k = numSlots - 1;
259 c[0] = k - p + 1;
260 for (h = 2; h <= p; h++) {
261 longmult1(c, (k - p + h), c, 5); /* c *= k - p + h; */
262 longdiv(c, h, c, r, 5); /* c /= h; */
263 FDK_ASSERT(*r == 0);
264 }
265
266 /* go through all slots */
267 for (; k >= 0; k--) {
268 if (p > k) {
269 for (; k >= 0; k--) {
270 phaseData[k] = 1; /* means TsdSepData[] = 1 */
271 }
272 break;
273 }
274 if (longcompare(s, c, 4)) { /* (s >= c) */
275 longsub(s, c, 4, 4); /* s -= c; */
276 phaseData[k] = 1; /* means TsdSepData[] = 1 */
277 if (p == 1) {
278 break;
279 }
280 /* Update c for next iteration: c_new = c_old * p / k */
281 longmult1(c, p, c, 5);
282 p--;
283 } else {
284 /* Update c for next iteration: c_new = c_old * (k-p) / k */
285 longmult1(c, (k - p), c, 5);
286 }
287 longdiv(c, k, c, r, 5);
288 FDK_ASSERT(*r == 0);
289 }
290
291 /* Read phase data */
292 for (k = 0; k < numSlots; k++) {
293 if (phaseData[k] == 1) {
294 phaseData[k] = FDKreadBits(hBs, 3);
295 }
296 }
297 }
298
299 return 0;
300 }
301
TsdGenerateNonTr(const int numHybridBands,const TSD_DATA * pTsdData,const int ts,FIXP_DBL * pVdirectReal,FIXP_DBL * pVdirectImag,FIXP_DBL * pVnonTrReal,FIXP_DBL * pVnonTrImag,FIXP_DBL ** ppDecorrInReal,FIXP_DBL ** ppDecorrInImag)302 void TsdGenerateNonTr(const int numHybridBands, const TSD_DATA *pTsdData,
303 const int ts, FIXP_DBL *pVdirectReal,
304 FIXP_DBL *pVdirectImag, FIXP_DBL *pVnonTrReal,
305 FIXP_DBL *pVnonTrImag, FIXP_DBL **ppDecorrInReal,
306 FIXP_DBL **ppDecorrInImag) {
307 int k = 0;
308
309 if (!isTrSlot(pTsdData, ts)) {
310 /* Let allpass based decorrelator read from direct input. */
311 *ppDecorrInReal = pVdirectReal;
312 *ppDecorrInImag = pVdirectImag;
313 return;
314 }
315
316 /* Generate nonTr input signal for allpass based decorrelator */
317 for (; k < TSD_START_BAND; k++) {
318 pVnonTrReal[k] = pVdirectReal[k];
319 pVnonTrImag[k] = pVdirectImag[k];
320 }
321 for (; k < numHybridBands; k++) {
322 pVnonTrReal[k] = (FIXP_DBL)0;
323 pVnonTrImag[k] = (FIXP_DBL)0;
324 }
325 *ppDecorrInReal = pVnonTrReal;
326 *ppDecorrInImag = pVnonTrImag;
327 }
328
TsdApply(const int numHybridBands,const TSD_DATA * pTsdData,int * pTsdTs,const FIXP_DBL * pVdirectReal,const FIXP_DBL * pVdirectImag,FIXP_DBL * pDnonTrReal,FIXP_DBL * pDnonTrImag)329 void TsdApply(const int numHybridBands, const TSD_DATA *pTsdData, int *pTsdTs,
330 const FIXP_DBL *pVdirectReal, const FIXP_DBL *pVdirectImag,
331 FIXP_DBL *pDnonTrReal, FIXP_DBL *pDnonTrImag) {
332 const int ts = *pTsdTs;
333
334 if (isTrSlot(pTsdData, ts)) {
335 int k;
336 const FIXP_STP *phi = &phiTsd[pTsdData->bsTsdTrPhaseData[ts]];
337 FDK_ASSERT((pTsdData->bsTsdTrPhaseData[ts] >= 0) &&
338 (pTsdData->bsTsdTrPhaseData[ts] < 8));
339
340 /* d = d_nonTr + v_direct * exp(j * bsTsdTrPhaseData[ts]/4 * pi ) */
341 for (k = TSD_START_BAND; k < numHybridBands; k++) {
342 FIXP_DBL tempReal, tempImag;
343 cplxMult(&tempReal, &tempImag, pVdirectReal[k], pVdirectImag[k], *phi);
344 pDnonTrReal[k] += tempReal;
345 pDnonTrImag[k] += tempImag;
346 }
347 }
348
349 /* The modulo MAX_TSD_TIME_SLOTS operation is to avoid illegal memory accesses
350 * in case of errors. */
351 *pTsdTs = (ts + 1) & (MAX_TSD_TIME_SLOTS - 1);
352 return;
353 }
354