mp3common.h
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- /* ***** BEGIN LICENSE BLOCK *****
- * Version: RCSL 1.0/RPSL 1.0
- *
- * Portions Copyright (c) 1995-2002 RealNetworks, Inc. All Rights Reserved.
- *
- * The contents of this file, and the files included with this file, are
- * subject to the current version of the RealNetworks Public Source License
- * Version 1.0 (the "RPSL") available at
- * http://www.helixcommunity.org/content/rpsl unless you have licensed
- * the file under the RealNetworks Community Source License Version 1.0
- * (the "RCSL") available at http://www.helixcommunity.org/content/rcsl,
- * in which case the RCSL will apply. You may also obtain the license terms
- * directly from RealNetworks. You may not use this file except in
- * compliance with the RPSL or, if you have a valid RCSL with RealNetworks
- * applicable to this file, the RCSL. Please see the applicable RPSL or
- * RCSL for the rights, obligations and limitations governing use of the
- * contents of the file.
- *
- * This file is part of the Helix DNA Technology. RealNetworks is the
- * developer of the Original Code and owns the copyrights in the portions
- * it created.
- *
- * This file, and the files included with this file, is distributed and made
- * available on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND REALNETWORKS HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS
- * FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- *
- * Technology Compatibility Kit Test Suite(s) Location:
- * http://www.helixcommunity.org/content/tck
- *
- * Contributor(s):
- *
- * ***** END LICENSE BLOCK ***** */
- /**************************************************************************************
- * Fixed-point MP3 decoder
- * Jon Recker (jrecker@real.com), Ken Cooke (kenc@real.com)
- * June 2003
- *
- * mp3common.h - implementation-independent API's, datatypes, and definitions
- **************************************************************************************/
- #ifndef _MP3COMMON_H
- #define _MP3COMMON_H
- #include "mp3dec.h"
- #include "statname.h" /* do name-mangling for static linking */
- #define MAX_SCFBD 4 /* max scalefactor bands per channel */
- #define NGRANS_MPEG1 2
- #define NGRANS_MPEG2 1
- /* 11-bit syncword if MPEG 2.5 extensions are enabled */
- #define SYNCWORDH 0xff
- #define SYNCWORDL 0xe0
- /* 12-bit syncword if MPEG 1,2 only are supported
- * #define SYNCWORDH 0xff
- * #define SYNCWORDL 0xf0
- */
- typedef struct _MP3DecInfo {
- /* pointers to platform-specific data structures */
- void *FrameHeaderPS;
- void *SideInfoPS;
- void *ScaleFactorInfoPS;
- void *HuffmanInfoPS;
- void *DequantInfoPS;
- void *IMDCTInfoPS;
- void *SubbandInfoPS;
- /* buffer which must be large enough to hold largest possible main_data section */
- unsigned char mainBuf[MAINBUF_SIZE];
- /* special info for "free" bitrate files */
- int freeBitrateFlag;
- int freeBitrateSlots;
- /* user-accessible info */
- int bitrate;
- int nChans;
- int samprate;
- int nGrans; /* granules per frame */
- int nGranSamps; /* samples per granule */
- int nSlots;
- int layer;
- MPEGVersion version;
- int mainDataBegin;
- int mainDataBytes;
- int part23Length[MAX_NGRAN][MAX_NCHAN];
- } MP3DecInfo;
- typedef struct _SFBandTable {
- short l[23];
- short s[14];
- } SFBandTable;
- /* decoder functions which must be implemented for each platform */
- MP3DecInfo *AllocateBuffers(void);
- void FreeBuffers(MP3DecInfo *mp3DecInfo);
- int CheckPadBit(MP3DecInfo *mp3DecInfo);
- int UnpackFrameHeader(MP3DecInfo *mp3DecInfo, unsigned char *buf);
- int UnpackSideInfo(MP3DecInfo *mp3DecInfo, unsigned char *buf);
- int DecodeHuffman(MP3DecInfo *mp3DecInfo, unsigned char *buf, int *bitOffset, int huffBlockBits, int gr, int ch);
- int Dequantize(MP3DecInfo *mp3DecInfo, int gr);
- int IMDCT(MP3DecInfo *mp3DecInfo, int gr, int ch);
- int UnpackScaleFactors(MP3DecInfo *mp3DecInfo, unsigned char *buf, int *bitOffset, int bitsAvail, int gr, int ch);
- int Subband(MP3DecInfo *mp3DecInfo, short *pcmBuf);
- /* mp3tabs.c - global ROM tables */
- extern const int samplerateTab[3][3];
- extern const short bitrateTab[3][3][15];
- extern const short samplesPerFrameTab[3][3];
- extern const short bitsPerSlotTab[3];
- extern const short sideBytesTab[3][2];
- extern const short slotTab[3][3][15];
- extern const SFBandTable sfBandTable[3][3];
- #endif /* _MP3COMMON_H */