/* * libmad - MPEG audio decoder library * Copyright (C) 2000-2004 Underbit Technologies, Inc. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA * * $Id: frame.h,v 1.20 2004/01/23 09:41:32 rob Exp $ */# ifndef LIBMAD_FRAME_H# define LIBMAD_FRAME_H# include "fixed.h"# include "timer.h"# include "stream.h"enum mad_layer {  MAD_LAYER_I   = 1,			/* Layer I */  MAD_LAYER_II  = 2,			/* Layer II */  MAD_LAYER_III = 3			/* Layer III */};enum mad_mode {  MAD_MODE_SINGLE_CHANNEL = 0,		/* single channel */  MAD_MODE_DUAL_CHANNEL	  = 1,		/* dual channel */  MAD_MODE_JOINT_STEREO	  = 2,		/* joint (MS/intensity) stereo */  MAD_MODE_STEREO	  = 3		/* normal LR stereo */};enum mad_emphasis {  MAD_EMPHASIS_NONE	  = 0,		/* no emphasis */  MAD_EMPHASIS_50_15_US	  = 1,		/* 50/15 microseconds emphasis */  MAD_EMPHASIS_CCITT_J_17 = 3,		/* CCITT J.17 emphasis */  MAD_EMPHASIS_RESERVED   = 2		/* unknown emphasis */};struct mad_header {  enum mad_layer layer;			/* audio layer (1, 2, or 3) */  enum mad_mode mode;			/* channel mode (see above) */  int mode_extension;			/* additional mode info */  enum mad_emphasis emphasis;		/* de-emphasis to use (see above) */  unsigned long bitrate;		/* stream bitrate (bps) */  unsigned int samplerate;		/* sampling frequency (Hz) */  unsigned short crc_check;		/* frame CRC accumulator */  unsigned short crc_target;		/* final target CRC checksum */  int flags;				/* flags (see below) */  int private_bits;			/* private bits (see below) */  mad_timer_t duration;			/* audio playing time of frame */};struct mad_frame {  struct mad_header header;		/* MPEG audio header */  int options;				/* decoding options (from stream) */  mad_fixed_t sbsample[2][36][32];	/* synthesis subband filter samples */  mad_fixed_t (*overlap)[2][32][18];	/* Layer III block overlap data */};# define MAD_NCHANNELS(header)		((header)->mode ? 2 : 1)# define MAD_NSBSAMPLES(header)  \  ((header)->layer == MAD_LAYER_I ? 12 :  \   (((header)->layer == MAD_LAYER_III &&  \     ((header)->flags & MAD_FLAG_LSF_EXT)) ? 18 : 36))enum {  MAD_FLAG_NPRIVATE_III	= 0x0007,	/* number of Layer III private bits */  MAD_FLAG_INCOMPLETE	= 0x0008,	/* header but not data is decoded */  MAD_FLAG_PROTECTION	= 0x0010,	/* frame has CRC protection */  MAD_FLAG_COPYRIGHT	= 0x0020,	/* frame is copyright */  MAD_FLAG_ORIGINAL	= 0x0040,	/* frame is original (else copy) */  MAD_FLAG_PADDING	= 0x0080,	/* frame has additional slot */  MAD_FLAG_I_STEREO	= 0x0100,	/* uses intensity joint stereo */  MAD_FLAG_MS_STEREO	= 0x0200,	/* uses middle/side joint stereo */  MAD_FLAG_FREEFORMAT	= 0x0400,	/* uses free format bitrate */  MAD_FLAG_LSF_EXT	= 0x1000,	/* lower sampling freq. extension */  MAD_FLAG_MC_EXT	= 0x2000,	/* multichannel audio extension */  MAD_FLAG_MPEG_2_5_EXT	= 0x4000	/* MPEG 2.5 (unofficial) extension */};enum {  MAD_PRIVATE_HEADER	= 0x0100,	/* header private bit */  MAD_PRIVATE_III	= 0x001f	/* Layer III private bits (up to 5) */};void mad_header_init(struct mad_header *);# define mad_header_finish(header)  /* nothing */int mad_header_decode(struct mad_header *, struct mad_stream *);void mad_frame_init(struct mad_frame *);void mad_frame_finish(struct mad_frame *);int mad_frame_decode(struct mad_frame *, struct mad_stream *);void mad_frame_mute(struct mad_frame *);# endif