1 
2 /* -----------------------------------------------------------------------------------------------------------
3 Software 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
9 The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements
10 the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
11 This FDK AAC Codec software is intended to be used on a wide variety of Android devices.
12 
13 AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual
14 audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by
15 independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part
16 of the MPEG specifications.
17 
18 Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
19 may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners
20 individually for the purpose of encoding or decoding bit streams in products that are compliant with
21 the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license
22 these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec
23 software may already be covered under those patent licenses when it is used for those licensed purposes only.
24 
25 Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
26 are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional
27 applications information and documentation.
28 
29 2.    COPYRIGHT LICENSE
30 
31 Redistribution and use in source and binary forms, with or without modification, are permitted without
32 payment of copyright license fees provided that you satisfy the following conditions:
33 
34 You must retain the complete text of this software license in redistributions of the FDK AAC Codec or
35 your modifications thereto in source code form.
36 
37 You must retain the complete text of this software license in the documentation and/or other materials
38 provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form.
39 You must make available free of charge copies of the complete source code of the FDK AAC Codec and your
40 modifications thereto to recipients of copies in binary form.
41 
42 The name of Fraunhofer may not be used to endorse or promote products derived from this library without
43 prior written permission.
44 
45 You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec
46 software or your modifications thereto.
47 
48 Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software
49 and 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 
53 3.    NO PATENT LICENSE
54 
55 NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer,
56 ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with
57 respect to this software.
58 
59 You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized
60 by appropriate patent licenses.
61 
62 4.    DISCLAIMER
63 
64 This 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
66 of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
67 CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages,
68 including but not limited to procurement of substitute goods or services; loss of use, data, or profits,
69 or business interruption, however caused and on any theory of liability, whether in contract, strict
70 liability, or tort (including negligence), arising in any way out of the use of this software, even if
71 advised of the possibility of such damage.
72 
73 5.    CONTACT INFORMATION
74 
75 Fraunhofer Institute for Integrated Circuits IIS
76 Attention: Audio and Multimedia Departments - FDK AAC LL
77 Am Wolfsmantel 33
78 91058 Erlangen, Germany
79 
80 www.iis.fraunhofer.de/amm
81 amm-info@iis.fraunhofer.de
82 ----------------------------------------------------------------------------------------------------------- */
83 
84 /*****************************  MPEG-4 AAC Encoder  **************************
85 
86    Author(s):   M. Werner
87    Description: Block switching
88 
89 ******************************************************************************/
90 
91 #ifndef _BLOCK_SWITCH_H
92 #define _BLOCK_SWITCH_H
93 
94 #include "common_fix.h"
95 
96 #include "psy_const.h"
97 
98 /****************** Defines ******************************/
99   #define BLOCK_SWITCH_WINDOWS    8                   /* number of windows for energy calculation */
100 
101 #define BLOCK_SWITCHING_IIR_LEN    2                  /* Length of HighPass-IIR-Filter for Attack-Detection */
102 #define BLOCK_SWITCH_ENERGY_SHIFT  7                  /* should be logDualis(BLOCK_SWITCH_WINDOW_LEN) to avoid overflow in windowNrgs. */
103 
104 #define LAST_WINDOW 0
105 #define THIS_WINDOW 1
106 
107 
108 /****************** Structures ***************************/
109 typedef struct{
110   INT   lastWindowSequence;
111   INT   windowShape;
112   INT   lastWindowShape;
113   UINT  nBlockSwitchWindows;                       /* number of windows for energy calculation */
114   INT   attack;
115   INT   lastattack;
116   INT   attackIndex;
117   INT   lastAttackIndex;
118   INT   allowShortFrames;                          /* for Low Delay, don't allow short frames */
119   INT   allowLookAhead;                            /* for Low Delay, don't do look-ahead */
120   INT   noOfGroups;
121   INT   groupLen[MAX_NO_OF_GROUPS];
122   FIXP_DBL maxWindowNrg;                           /* max energy in subwindows */
123 
124   FIXP_DBL windowNrg[2][BLOCK_SWITCH_WINDOWS];     /* time signal energy in Subwindows (last and current) */
125   FIXP_DBL windowNrgF[2][BLOCK_SWITCH_WINDOWS];    /* filtered time signal energy in segments (last and current) */
126   FIXP_DBL accWindowNrg;                           /* recursively accumulated windowNrgF */
127 
128   FIXP_DBL iirStates[BLOCK_SWITCHING_IIR_LEN];     /* filter delay-line */
129 
130 } BLOCK_SWITCHING_CONTROL;
131 
132 
133 
134 
135 
136 void FDKaacEnc_InitBlockSwitching(BLOCK_SWITCHING_CONTROL *blockSwitchingControl, INT isLowDelay);
137 
138 int FDKaacEnc_BlockSwitching(BLOCK_SWITCHING_CONTROL *blockSwitchingControl, const INT granuleLength, const int isLFE, const INT_PCM *pTimeSignal);
139 
140 int FDKaacEnc_SyncBlockSwitching(
141       BLOCK_SWITCHING_CONTROL *blockSwitchingControlLeft,
142       BLOCK_SWITCHING_CONTROL *blockSwitchingControlRight,
143       const INT noOfChannels,
144       const INT commonWindow);
145 
146 #endif  /* #ifndef _BLOCK_SWITCH_H */
147