apps/codecs/libtremor/ivorbiscodec.h

   1 /********************************************************************
   2  *                                                                  *
   3  * THIS FILE IS PART OF THE OggVorbis 'TREMOR' CODEC SOURCE CODE.   *
   4  *                                                                  *
   5  * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
   6  * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
   7  * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
   8  *                                                                  *
   9  * THE OggVorbis 'TREMOR' SOURCE CODE IS (C) COPYRIGHT 1994-2002    *
  10  * BY THE Xiph.Org FOUNDATION http://www.xiph.org/                  *
  11  *                                                                  *
  12  ********************************************************************
  13
  14  function: libvorbis codec headers
  15
  16  ********************************************************************/
  17
  18 #ifndef _vorbis_codec_h_
  19 #define _vorbis_codec_h_
  20
  21 #ifdef __cplusplus
  22 extern "C"
  23 {
  24 #endif /* __cplusplus */
  25
  26 #include "ogg.h"
  27
  28 typedef struct vorbis_info{
  29   int version;
  30   int channels;
  31   long rate;
  32
  33   /* The below bitrate declarations are *hints*.
  34      Combinations of the three values carry the following implications:
  35
  36      all three set to the same value:
  37        implies a fixed rate bitstream
  38      only nominal set:
  39        implies a VBR stream that averages the nominal bitrate.  No hard
  40        upper/lower limit
  41      upper and or lower set:
  42        implies a VBR bitstream that obeys the bitrate limits. nominal
  43        may also be set to give a nominal rate.
  44      none set:
  45        the coder does not care to speculate.
  46   */
  47
  48   long bitrate_upper;
  49   long bitrate_nominal;
  50   long bitrate_lower;
  51
  52   void *codec_setup;
  53 } vorbis_info;
  54
  55 /* vorbis_dsp_state buffers the current vorbis audio
  56    analysis/synthesis state.  The DSP state belongs to a specific
  57    logical bitstream ****************************************************/
  58 typedef struct vorbis_dsp_state{
  59   vorbis_info *vi;
  60
  61   ogg_int32_t **pcm;
  62   ogg_int32_t **pcmb;
  63   ogg_int32_t **pcmret;
  64   int      pcm_storage;
  65   int      pcm_current;
  66   int      pcm_returned;
  67
  68   int  eofflag;
  69
  70   long lW;
  71   long W;
  72   long nW;
  73   long centerW;
  74
  75   ogg_int64_t granulepos;
  76   ogg_int64_t sequence;
  77
  78   void       *backend_state;
  79 } vorbis_dsp_state;
  80
  81 typedef struct vorbis_block{
  82   /* necessary stream state for linking to the framing abstraction */
  83   ogg_int32_t  **pcm;       /* this is a pointer into local storage */
  84   oggpack_buffer opb;
  85
  86   long  lW;
  87   long  W;
  88   long  nW;
  89   int   pcmend;
  90   int   mode;
  91
  92   int         eofflag;
  93   ogg_int64_t granulepos;
  94   ogg_int64_t sequence;
  95   vorbis_dsp_state *vd; /* For read-only access of configuration */
  96
  97   /* local storage to avoid remallocing; it's up to the mapping to
  98      structure it */
  99   void               *localstore;
 100   long                localtop;
 101   long                localalloc;
 102   long                totaluse;
 103   struct alloc_chain *reap;
 104
 105 } vorbis_block;
 106
 107 /* vorbis_block is a single block of data to be processed as part of
 108 the analysis/synthesis stream; it belongs to a specific logical
 109 bitstream, but is independant from other vorbis_blocks belonging to
 110 that logical bitstream. *************************************************/
 111
 112 struct alloc_chain{
 113   void *ptr;
 114   struct alloc_chain *next;
 115 };
 116
 117 /* vorbis_info contains all the setup information specific to the
 118    specific compression/decompression mode in progress (eg,
 119    psychoacoustic settings, channel setup, options, codebook
 120    etc). vorbis_info and substructures are in backends.h.
 121 *********************************************************************/
 122
 123 /* the comments are not part of vorbis_info so that vorbis_info can be
 124    static storage */
 125 typedef struct vorbis_comment{
 126   /* unlimited user comment fields.  libvorbis writes 'libvorbis'
 127      whatever vendor is set to in encode */
 128   char **user_comments;
 129   int   *comment_lengths;
 130   int    comments;
 131   char  *vendor;
 132
 133 } vorbis_comment;
 134
 135
 136 /* libvorbis encodes in two abstraction layers; first we perform DSP
 137    and produce a packet (see docs/analysis.txt).  The packet is then
 138    coded into a framed OggSquish bitstream by the second layer (see
 139    docs/framing.txt).  Decode is the reverse process; we sync/frame
 140    the bitstream and extract individual packets, then decode the
 141    packet back into PCM audio.
 142
 143    The extra framing/packetizing is used in streaming formats, such as
 144    files.  Over the net (such as with UDP), the framing and
 145    packetization aren't necessary as they're provided by the transport
 146    and the streaming layer is not used */
 147
 148 /* Vorbis PRIMITIVES: general ***************************************/
 149
 150 extern void     vorbis_info_init(vorbis_info *vi);
 151 extern void     vorbis_info_clear(vorbis_info *vi);
 152 extern int      vorbis_info_blocksize(vorbis_info *vi,int zo);
 153 extern void     vorbis_comment_init(vorbis_comment *vc);
 154 extern void     vorbis_comment_add(vorbis_comment *vc, char *comment);
 155 extern void     vorbis_comment_add_tag(vorbis_comment *vc,
 156                                        char *tag, char *contents);
 157 extern void     vorbis_comment_clear(vorbis_comment *vc);
 158
 159 extern int      vorbis_block_init(vorbis_dsp_state *v, vorbis_block *vb);
 160 extern int      vorbis_block_clear(vorbis_block *vb);
 161 extern void     vorbis_dsp_clear(vorbis_dsp_state *v);
 162
 163 /* Vorbis PRIMITIVES: synthesis layer *******************************/
 164 extern int      vorbis_synthesis_headerin(vorbis_info *vi,vorbis_comment *vc,
 165                                           ogg_packet *op);
 166
 167 extern int      vorbis_synthesis_init(vorbis_dsp_state *v,vorbis_info *vi);
 168 extern int      vorbis_synthesis_restart(vorbis_dsp_state *v);
 169 extern int      vorbis_synthesis(vorbis_block *vb,ogg_packet *op,int decodep);
 170 extern int      vorbis_synthesis_blockin(vorbis_dsp_state *v,vorbis_block *vb);
 171 extern int      vorbis_synthesis_pcmout(vorbis_dsp_state *v,ogg_int32_t ***pcm);
 172 extern int      vorbis_synthesis_read(vorbis_dsp_state *v,int samples);
 173 extern long     vorbis_packet_blocksize(vorbis_info *vi,ogg_packet *op);
 174
 175 /* Vorbis ERRORS and return codes ***********************************/
 176
 177 #define OV_FALSE      -1
 178 #define OV_EOF        -2
 179 #define OV_HOLE       -3
 180
 181 #define OV_EREAD      -128
 182 #define OV_EFAULT     -129
 183 #define OV_EIMPL      -130
 184 #define OV_EINVAL     -131
 185 #define OV_ENOTVORBIS -132
 186 #define OV_EBADHEADER -133
 187 #define OV_EVERSION   -134
 188 #define OV_ENOTAUDIO  -135
 189 #define OV_EBADPACKET -136
 190 #define OV_EBADLINK   -137
 191 #define OV_ENOSEEK    -138
 192
 193 #ifdef __cplusplus
 194 }
 195 #endif /* __cplusplus */
 196
 197 #endif
 198