apps/codecs/demac/libdemac/parser.h

   1 /*
   2
   3 libdemac - A Monkey's Audio decoder
   4
   5 $Id$
   6
   7 Copyright (C) Dave Chapman 2007
   8
   9 This program is free software; you can redistribute it and/or modify
  10 it under the terms of the GNU General Public License as published by
  11 the Free Software Foundation; either version 2 of the License, or
  12 (at your option) any later version.
  13
  14 This program is distributed in the hope that it will be useful,
  15 but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 GNU General Public License for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with this program; if not, write to the Free Software
  21 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110, USA
  22
  23 */
  24
  25 #ifndef _APE_PARSER_H
  26 #define _APE_PARSER_H
  27
  28 #include <inttypes.h>
  29 #include "demac_config.h"
  30
  31 /* The earliest and latest file formats supported by this library */
  32 #define APE_MIN_VERSION 3970
  33 #define APE_MAX_VERSION 3990
  34
  35 #define MAC_FORMAT_FLAG_8_BIT                 1    // is 8-bit [OBSOLETE]
  36 #define MAC_FORMAT_FLAG_CRC                   2    // uses the new CRC32 error detection [OBSOLETE]
  37 #define MAC_FORMAT_FLAG_HAS_PEAK_LEVEL        4    // uint32 nPeakLevel after the header [OBSOLETE]
  38 #define MAC_FORMAT_FLAG_24_BIT                8    // is 24-bit [OBSOLETE]
  39 #define MAC_FORMAT_FLAG_HAS_SEEK_ELEMENTS    16    // has the number of seek elements after the peak level
  40 #define MAC_FORMAT_FLAG_CREATE_WAV_HEADER    32    // create the wave header on decompression (not stored)
  41
  42
  43 /* Special frame codes:
  44
  45    MONO_SILENCE - All PCM samples in frame are zero (mono streams only)
  46    LEFT_SILENCE - All PCM samples for left channel in frame are zero (stereo streams)
  47    RIGHT_SILENCE - All PCM samples for left channel in frame are zero (stereo streams)
  48    PSEUDO_STEREO - Left and Right channels are identical
  49
  50 */
  51
  52 #define APE_FRAMECODE_MONO_SILENCE    1
  53 #define APE_FRAMECODE_LEFT_SILENCE    1 /* same as mono */
  54 #define APE_FRAMECODE_RIGHT_SILENCE   2
  55 #define APE_FRAMECODE_STEREO_SILENCE  3 /* combined */
  56 #define APE_FRAMECODE_PSEUDO_STEREO   4
  57
  58 #define PREDICTOR_ORDER 8
  59 /* Total size of all predictor histories - 50 * sizeof(int32_t) */
  60 #define PREDICTOR_SIZE 50
  61
  62
  63 /* NOTE: This struct is used in predictor-arm.S - any updates need to
  64    be reflected there. */
  65
  66 struct predictor_t
  67 {
  68     /* Filter histories */
  69     int32_t* buf;
  70
  71     int32_t YlastA;
  72     int32_t XlastA;
  73
  74     /* NOTE: The order of the next four fields is important for
  75        predictor-arm.S */
  76     int32_t YfilterB;
  77     int32_t XfilterA;
  78     int32_t XfilterB;
  79     int32_t YfilterA;
  80
  81     /* Adaption co-efficients */
  82     int32_t YcoeffsA[4];
  83     int32_t XcoeffsA[4];
  84     int32_t YcoeffsB[5];
  85     int32_t XcoeffsB[5];
  86     int32_t historybuffer[PREDICTOR_HISTORY_SIZE + PREDICTOR_SIZE];
  87 };
  88
  89 struct ape_ctx_t
  90 {
  91     /* Derived fields */
  92     uint32_t      junklength;
  93     uint32_t      firstframe;
  94     uint32_t      totalsamples;
  95
  96     /* Info from Descriptor Block */
  97     char          magic[4];
  98     int16_t       fileversion;
  99     int16_t       padding1;
 100     uint32_t      descriptorlength;
 101     uint32_t      headerlength;
 102     uint32_t      seektablelength;
 103     uint32_t      wavheaderlength;
 104     uint32_t      audiodatalength;
 105     uint32_t      audiodatalength_high;
 106     uint32_t      wavtaillength;
 107     uint8_t       md5[16];
 108
 109     /* Info from Header Block */
 110     uint16_t      compressiontype;
 111     uint16_t      formatflags;
 112     uint32_t      blocksperframe;
 113     uint32_t      finalframeblocks;
 114     uint32_t      totalframes;
 115     uint16_t      bps;
 116     uint16_t      channels;
 117     uint32_t      samplerate;
 118
 119     /* Seektable */
 120     uint32_t*     seektable;        /* Seektable buffer */
 121     uint32_t      maxseekpoints;    /* Max seekpoints we can store (size of seektable buffer) */
 122     uint32_t      numseekpoints;    /* Number of seekpoints */
 123     int           seektablefilepos; /* Location in .ape file of seektable */
 124
 125     /* Decoder state */
 126     uint32_t      CRC;
 127     int           frameflags;
 128     int           currentframeblocks;
 129     int           blocksdecoded;
 130     struct predictor_t predictor;
 131 };
 132
 133 int ape_parseheader(int fd, struct ape_ctx_t* ape_ctx);
 134 int ape_parseheaderbuf(unsigned char* buf, struct ape_ctx_t* ape_ctx);
 135 void ape_dumpinfo(struct ape_ctx_t* ape_ctx);
 136
 137 #endif