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 Decoder  **************************
85 
86    Author(s):   Josef Hoepfl
87    Description: ADTS interface
88 
89 ******************************************************************************/
90 
91 #ifndef TPDEC_ADTS_H
92 #define TPDEC_ADTS_H
93 
94 #include "tpdec_lib.h"
95 
96 
97 #define ADTS_SYNCWORD               ( 0xfff )
98 #define ADTS_SYNCLENGTH             ( 12 )     /* in bits */
99 #define ADTS_HEADERLENGTH           ( 56 )     /* minimum header size in bits */
100 #define ADTS_FIXED_HEADERLENGTH     ( 28 )     /* in bits */
101 #define ADTS_VARIABLE_HEADERLENGTH  ( ADTS_HEADERLENGTH - ADTS_FIXED_HEADERLENGTH )
102 
103 #ifdef CHECK_TWO_SYNCS
104  #define ADTS_MIN_TP_BUF_SIZE       ( 8191 + 2 )
105 #else
106  #define ADTS_MIN_TP_BUF_SIZE       ( 8191 )
107 #endif
108 
109 #include "FDK_crc.h"
110 
111 typedef struct {
112   /* ADTS header fields */
113   UCHAR mpeg_id;
114   UCHAR layer;
115   UCHAR protection_absent;
116   UCHAR profile;
117   UCHAR sample_freq_index;
118   UCHAR private_bit;
119   UCHAR channel_config;
120   UCHAR original;
121   UCHAR home;
122   UCHAR copyright_id;
123   UCHAR copyright_start;
124   USHORT frame_length;
125   USHORT adts_fullness;
126   UCHAR num_raw_blocks;
127   UCHAR num_pce_bits;
128 } STRUCT_ADTS_BS;
129 
130 struct STRUCT_ADTS {
131 
132   STRUCT_ADTS_BS bs;
133 
134   UCHAR decoderCanDoMpeg4;
135   UCHAR BufferFullnesStartFlag;
136 
137   FDK_CRCINFO crcInfo;             /* CRC state info */
138   USHORT      crcReadValue;        /* CRC value read from bitstream data */
139   USHORT      rawDataBlockDist[4]; /* distance between each raw data block. Not the same as found in the bitstream */
140 } ;
141 
142 typedef struct STRUCT_ADTS *HANDLE_ADTS;
143 
144 /*!
145   \brief Initialize ADTS CRC
146 
147   The function initialzes the crc buffer and the crc lookup table.
148 
149   \return  none
150 */
151 void adtsRead_CrcInit( HANDLE_ADTS pAdts );
152 
153 /**
154  * \brief Starts CRC region with a maximum number of bits
155  *        If mBits is positive zero padding will be used for CRC calculation, if there
156  *        are less than mBits bits available.
157  *        If mBits is negative no zero padding is done.
158  *        If mBits is zero the memory for the buffer is allocated dynamically, the
159  *        number of bits is not limited.
160  *
161  * \param pAdts ADTS data handle
162  * \param hBs bitstream handle, on which the CRC region referes to
163  * \param mBits max number of bits in crc region to be considered
164  *
165  * \return  ID for the created region, -1 in case of an error
166  */
167 int adtsRead_CrcStartReg(
168         HANDLE_ADTS pAdts,
169         HANDLE_FDK_BITSTREAM hBs,
170         int mBits
171         );
172 
173 /**
174  * \brief Ends CRC region identified by reg
175  *
176  * \param pAdts ADTS data handle
177  * \param hBs bitstream handle, on which the CRC region referes to
178  * \param reg CRC regions ID returned by adtsRead_CrcStartReg()
179  *
180  * \return  none
181  */
182 void adtsRead_CrcEndReg(
183         HANDLE_ADTS pAdts,
184         HANDLE_FDK_BITSTREAM hBs,
185         int reg
186         );
187 
188 /**
189  * \brief Check CRC
190  *
191  * Checks if the currently calculated CRC matches the CRC field read from the bitstream
192  * Deletes all CRC regions.
193  *
194  * \param pAdts ADTS data handle
195  *
196  * \return Returns 0 if they are identical otherwise 1
197  */
198 TRANSPORTDEC_ERROR adtsRead_CrcCheck( HANDLE_ADTS pAdts );
199 
200 
201 /**
202  * \brief Check if we have a valid ADTS frame at the current bitbuffer position
203  *
204  * This function assumes enough bits in buffer for the current frame.
205  * It reads out the header bits to prepare the bitbuffer for the decode loop.
206  * In case the header bits show an invalid bitstream/frame, the whole frame is skipped.
207  *
208  * \param pAdts ADTS data handle which is filled with parsed ADTS header data
209  * \param bs handle of bitstream from whom the ADTS header is read
210  *
211  * \return  error status
212  */
213 TRANSPORTDEC_ERROR adtsRead_DecodeHeader(
214         HANDLE_ADTS           pAdts,
215         CSAudioSpecificConfig *pAsc,
216         HANDLE_FDK_BITSTREAM  bs,
217         const INT             ignoreBufferFullness
218         );
219 
220 /**
221  * \brief Get the raw data block length of the given block number.
222  *
223  * \param pAdts ADTS data handle
224  * \param blockNum current raw data block index
225  * \param pLength pointer to an INT where the length of the given raw data block is stored into
226  *                the returned value might be -1, in which case the raw data block length is unknown.
227  *
228  * \return  error status
229  */
230 int adtsRead_GetRawDataBlockLength(
231         HANDLE_ADTS pAdts,
232         INT         blockNum
233         );
234 
235 
236 #endif /* TPDEC_ADTS_H */
237