1
2/* -----------------------------------------------------------------------------------------------------------
3Software License for The Fraunhofer FDK AAC Codec Library for Android
4
5� Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur F�rderung der angewandten Forschung e.V.
6  All rights reserved.
7
8 1.    INTRODUCTION
9The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements
10the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
11This FDK AAC Codec software is intended to be used on a wide variety of Android devices.
12
13AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual
14audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by
15independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part
16of the MPEG specifications.
17
18Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
19may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners
20individually for the purpose of encoding or decoding bit streams in products that are compliant with
21the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license
22these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec
23software may already be covered under those patent licenses when it is used for those licensed purposes only.
24
25Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
26are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional
27applications information and documentation.
28
292.    COPYRIGHT LICENSE
30
31Redistribution and use in source and binary forms, with or without modification, are permitted without
32payment of copyright license fees provided that you satisfy the following conditions:
33
34You must retain the complete text of this software license in redistributions of the FDK AAC Codec or
35your modifications thereto in source code form.
36
37You must retain the complete text of this software license in the documentation and/or other materials
38provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form.
39You must make available free of charge copies of the complete source code of the FDK AAC Codec and your
40modifications thereto to recipients of copies in binary form.
41
42The name of Fraunhofer may not be used to endorse or promote products derived from this library without
43prior written permission.
44
45You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec
46software or your modifications thereto.
47
48Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software
49and the date of any change. For modified versions of the FDK AAC Codec, the term
50"Fraunhofer FDK AAC Codec Library for Android" must be replaced by the term
51"Third-Party Modified Version of the Fraunhofer FDK AAC Codec Library for Android."
52
533.    NO PATENT LICENSE
54
55NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer,
56ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with
57respect to this software.
58
59You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized
60by appropriate patent licenses.
61
624.    DISCLAIMER
63
64This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright holders and contributors
65"AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, including but not limited to the implied warranties
66of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
67CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages,
68including but not limited to procurement of substitute goods or services; loss of use, data, or profits,
69or business interruption, however caused and on any theory of liability, whether in contract, strict
70liability, or tort (including negligence), arising in any way out of the use of this software, even if
71advised of the possibility of such damage.
72
735.    CONTACT INFORMATION
74
75Fraunhofer Institute for Integrated Circuits IIS
76Attention: Audio and Multimedia Departments - FDK AAC LL
77Am Wolfsmantel 33
7891058 Erlangen, Germany
79
80www.iis.fraunhofer.de/amm
81amm-info@iis.fraunhofer.de
82----------------------------------------------------------------------------------------------------------- */
83
84/***************************  Fraunhofer IIS FDK Tools  ***********************
85
86   Author(s):   M. Lohwasser
87   Description: auto-correlation functions
88
89******************************************************************************/
90
91#include "autocorr2nd.h"
92
93
94
95/*  If the accumulator does not provide enough overflow bits,
96    products have to be shifted down in the autocorrelation below. */
97#define SHIFT_FACTOR (5)
98#define SHIFT >> (SHIFT_FACTOR)
99
100
101#if defined(__CC_ARM) || defined(__arm__)
102#include "arm/autocorr2nd.cpp"
103#endif
104
105
106/*!
107 *
108 * \brief Calculate second order autocorrelation using 2 accumulators
109 *
110 */
111#if !defined(FUNCTION_autoCorr2nd_real)
112INT
113autoCorr2nd_real (ACORR_COEFS *ac,          /*!< Pointer to autocorrelation coeffs */
114                  const FIXP_DBL *reBuffer, /*!< Pointer to to real part of input samples */
115                  const int len             /*!< Number input samples */
116                 )
117{
118  int   j, autoCorrScaling, mScale;
119
120  FIXP_DBL accu1, accu2, accu3, accu4, accu5;
121
122  const FIXP_DBL *pReBuf;
123
124  const FIXP_DBL *realBuf = reBuffer;
125
126  /*
127    r11r,r22r
128    r01r,r12r
129    r02r
130  */
131  pReBuf = realBuf-2;
132  accu5 = ( (fMultDiv2(pReBuf[0], pReBuf[2]) +
133             fMultDiv2(pReBuf[1], pReBuf[3])) SHIFT);
134  pReBuf++;
135
136  //len must be even
137  accu1 = fPow2Div2(pReBuf[0]) SHIFT;
138  accu3 = fMultDiv2(pReBuf[0], pReBuf[1]) SHIFT;
139  pReBuf++;
140
141  for ( j = (len - 2)>>1; j != 0; j--,pReBuf+=2 ) {
142
143    accu1 += ( (fPow2Div2(pReBuf[0]) +
144                fPow2Div2(pReBuf[1])) SHIFT);
145
146    accu3 += ( (fMultDiv2(pReBuf[0], pReBuf[1]) +
147                fMultDiv2(pReBuf[1], pReBuf[2])) SHIFT);
148
149    accu5 += ( (fMultDiv2(pReBuf[0], pReBuf[2]) +
150                fMultDiv2(pReBuf[1], pReBuf[3])) SHIFT);
151
152  }
153
154  accu2 = (fPow2Div2(realBuf[-2]) SHIFT);
155  accu2 += accu1;
156
157  accu1 += (fPow2Div2(realBuf[len - 2]) SHIFT);
158
159  accu4  = (fMultDiv2(realBuf[-1],realBuf[-2]) SHIFT);
160  accu4 += accu3;
161
162  accu3 += (fMultDiv2(realBuf[len - 1],realBuf[len - 2]) SHIFT);
163
164  mScale = CntLeadingZeros( (accu1 | accu2 | fAbs(accu3) | fAbs(accu4) | fAbs(accu5)) ) - 1;
165  autoCorrScaling = mScale - 1 - SHIFT_FACTOR; /* -1 because of fMultDiv2*/
166
167  /* Scale to common scale factor */
168  ac->r11r = accu1 << mScale;
169  ac->r22r = accu2 << mScale;
170  ac->r01r = accu3 << mScale;
171  ac->r12r = accu4 << mScale;
172  ac->r02r = accu5 << mScale;
173
174  ac->det = (fMultDiv2(ac->r11r,ac->r22r) - fMultDiv2(ac->r12r,ac->r12r)) ;
175  mScale  = CountLeadingBits(fAbs(ac->det));
176
177  ac->det     <<= mScale;
178  ac->det_scale = mScale - 1;
179
180  return autoCorrScaling;
181}
182#endif
183
184#ifndef LOW_POWER_SBR_ONLY
185#if !defined(FUNCTION_autoCorr2nd_cplx)
186INT
187autoCorr2nd_cplx (ACORR_COEFS *ac,           /*!< Pointer to autocorrelation coeffs */
188                  const FIXP_DBL *reBuffer,  /*!< Pointer to real part of input samples */
189                  const FIXP_DBL *imBuffer,  /*!< Pointer to imag part of input samples */
190                  const int len              /*!< Number of input samples */
191                 )
192{
193
194  int   j, autoCorrScaling, mScale, len_scale;
195
196  FIXP_DBL accu0, accu1,accu2, accu3, accu4, accu5, accu6, accu7, accu8;
197
198  const FIXP_DBL *pReBuf, *pImBuf;
199
200  const FIXP_DBL *realBuf = reBuffer;
201  const FIXP_DBL *imagBuf = imBuffer;
202
203  (len>64) ? (len_scale = 6) : (len_scale = 5);
204  /*
205    r00r,
206    r11r,r22r
207    r01r,r12r
208    r01i,r12i
209    r02r,r02i
210  */
211  accu1 = accu3 = accu5 = accu7 = accu8 = FL2FXCONST_DBL(0.0f);
212
213  pReBuf  = realBuf-2, pImBuf  = imagBuf-2;
214  accu7 += ( (fMultDiv2(pReBuf[2], pReBuf[0]) + fMultDiv2(pImBuf[2], pImBuf[0])) >> len_scale);
215  accu8 += ( (fMultDiv2(pImBuf[2], pReBuf[0]) - fMultDiv2(pReBuf[2], pImBuf[0])) >> len_scale);
216
217  pReBuf = realBuf-1, pImBuf = imagBuf-1;
218  for ( j = (len - 1); j != 0; j--,pReBuf++,pImBuf++ ){
219    accu1 += ( (fPow2Div2(pReBuf[0]           ) + fPow2Div2(pImBuf[0]           )) >> len_scale);
220    accu3 += ( (fMultDiv2(pReBuf[0], pReBuf[1]) + fMultDiv2(pImBuf[0], pImBuf[1])) >> len_scale);
221    accu5 += ( (fMultDiv2(pImBuf[1], pReBuf[0]) - fMultDiv2(pReBuf[1], pImBuf[0])) >> len_scale);
222    accu7 += ( (fMultDiv2(pReBuf[2], pReBuf[0]) + fMultDiv2(pImBuf[2], pImBuf[0])) >> len_scale);
223    accu8 += ( (fMultDiv2(pImBuf[2], pReBuf[0]) - fMultDiv2(pReBuf[2], pImBuf[0])) >> len_scale);
224  }
225
226  accu2 = ( (fPow2Div2(realBuf[-2]) + fPow2Div2(imagBuf[-2])) >> len_scale);
227  accu2 += accu1;
228
229  accu1 += ( (fPow2Div2(realBuf[len-2]) +
230              fPow2Div2(imagBuf[len-2])) >> len_scale);
231  accu0 = ( (fPow2Div2(realBuf[len-1]) +
232             fPow2Div2(imagBuf[len-1])) >> len_scale) -
233          ( (fPow2Div2(realBuf[-1]) +
234             fPow2Div2(imagBuf[-1])) >> len_scale);
235  accu0 += accu1;
236
237  accu4 = ( (fMultDiv2(realBuf[-1], realBuf[-2]) +
238             fMultDiv2(imagBuf[-1], imagBuf[-2])) >> len_scale);
239  accu4 += accu3;
240
241  accu3 += ( (fMultDiv2(realBuf[len-1], realBuf[len-2]) +
242              fMultDiv2(imagBuf[len-1], imagBuf[len-2])) >> len_scale);
243
244  accu6 = ( (fMultDiv2(imagBuf[-1], realBuf[-2]) -
245             fMultDiv2(realBuf[-1], imagBuf[-2])) >> len_scale);
246  accu6 += accu5;
247
248  accu5 += ( (fMultDiv2(imagBuf[len - 1], realBuf[len - 2]) -
249              fMultDiv2(realBuf[len - 1], imagBuf[len - 2])) >> len_scale);
250
251  mScale = CntLeadingZeros( (accu0 | accu1 | accu2 | fAbs(accu3) | fAbs(accu4) | fAbs(accu5) |
252                             fAbs(accu6) | fAbs(accu7) | fAbs(accu8)) ) - 1;
253  autoCorrScaling = mScale - 1 - len_scale; /* -1 because of fMultDiv2*/
254
255  /* Scale to common scale factor */
256  ac->r00r = (FIXP_DBL)accu0 << mScale;
257  ac->r11r = (FIXP_DBL)accu1 << mScale;
258  ac->r22r = (FIXP_DBL)accu2 << mScale;
259  ac->r01r = (FIXP_DBL)accu3 << mScale;
260  ac->r12r = (FIXP_DBL)accu4 << mScale;
261  ac->r01i = (FIXP_DBL)accu5 << mScale;
262  ac->r12i = (FIXP_DBL)accu6 << mScale;
263  ac->r02r = (FIXP_DBL)accu7 << mScale;
264  ac->r02i = (FIXP_DBL)accu8 << mScale;
265
266  ac->det = ( fMultDiv2(ac->r11r,ac->r22r) >> 1 ) -
267            ( (fMultDiv2(ac->r12r,ac->r12r) + fMultDiv2(ac->r12i,ac->r12i)) >> 1 );
268  mScale = CountLeadingBits(fAbs(ac->det));
269
270  ac->det <<= mScale;
271  ac->det_scale = mScale - 2;
272
273  return autoCorrScaling;
274}
275#endif /* FUNCTION_autoCorr2nd_cplx */
276#endif /* LOW_POWER_SBR_ONLY */
277
278
279