VisualC/vorbis/include/codec.h
author Sam Lantinga <slouken@libsdl.org>
Tue, 18 Jan 2011 11:11:21 -0800
changeset 495 b4d178cd982d
permissions -rwxr-xr-x
Updated version to 1.2.12
     1 /********************************************************************
     2  *                                                                  *
     3  * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
     4  * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
     5  * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
     6  * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
     7  *                                                                  *
     8  * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2001             *
     9  * by the Xiph.Org Foundation http://www.xiph.org/                  *
    10 
    11  ********************************************************************
    12 
    13  function: libvorbis codec headers
    14  last mod: $Id: codec.h 16037 2009-05-26 21:10:58Z xiphmont $
    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/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   long bitrate_window;
    52 
    53   void *codec_setup;
    54 } vorbis_info;
    55 
    56 /* vorbis_dsp_state buffers the current vorbis audio
    57    analysis/synthesis state.  The DSP state belongs to a specific
    58    logical bitstream ****************************************************/
    59 typedef struct vorbis_dsp_state{
    60   int analysisp;
    61   vorbis_info *vi;
    62 
    63   float **pcm;
    64   float **pcmret;
    65   int      pcm_storage;
    66   int      pcm_current;
    67   int      pcm_returned;
    68 
    69   int  preextrapolate;
    70   int  eofflag;
    71 
    72   long lW;
    73   long W;
    74   long nW;
    75   long centerW;
    76 
    77   ogg_int64_t granulepos;
    78   ogg_int64_t sequence;
    79 
    80   ogg_int64_t glue_bits;
    81   ogg_int64_t time_bits;
    82   ogg_int64_t floor_bits;
    83   ogg_int64_t res_bits;
    84 
    85   void       *backend_state;
    86 } vorbis_dsp_state;
    87 
    88 typedef struct vorbis_block{
    89   /* necessary stream state for linking to the framing abstraction */
    90   float  **pcm;       /* this is a pointer into local storage */
    91   oggpack_buffer opb;
    92 
    93   long  lW;
    94   long  W;
    95   long  nW;
    96   int   pcmend;
    97   int   mode;
    98 
    99   int         eofflag;
   100   ogg_int64_t granulepos;
   101   ogg_int64_t sequence;
   102   vorbis_dsp_state *vd; /* For read-only access of configuration */
   103 
   104   /* local storage to avoid remallocing; it's up to the mapping to
   105      structure it */
   106   void               *localstore;
   107   long                localtop;
   108   long                localalloc;
   109   long                totaluse;
   110   struct alloc_chain *reap;
   111 
   112   /* bitmetrics for the frame */
   113   long glue_bits;
   114   long time_bits;
   115   long floor_bits;
   116   long res_bits;
   117 
   118   void *internal;
   119 
   120 } vorbis_block;
   121 
   122 /* vorbis_block is a single block of data to be processed as part of
   123 the analysis/synthesis stream; it belongs to a specific logical
   124 bitstream, but is independant from other vorbis_blocks belonging to
   125 that logical bitstream. *************************************************/
   126 
   127 struct alloc_chain{
   128   void *ptr;
   129   struct alloc_chain *next;
   130 };
   131 
   132 /* vorbis_info contains all the setup information specific to the
   133    specific compression/decompression mode in progress (eg,
   134    psychoacoustic settings, channel setup, options, codebook
   135    etc). vorbis_info and substructures are in backends.h.
   136 *********************************************************************/
   137 
   138 /* the comments are not part of vorbis_info so that vorbis_info can be
   139    static storage */
   140 typedef struct vorbis_comment{
   141   /* unlimited user comment fields.  libvorbis writes 'libvorbis'
   142      whatever vendor is set to in encode */
   143   char **user_comments;
   144   int   *comment_lengths;
   145   int    comments;
   146   char  *vendor;
   147 
   148 } vorbis_comment;
   149 
   150 
   151 /* libvorbis encodes in two abstraction layers; first we perform DSP
   152    and produce a packet (see docs/analysis.txt).  The packet is then
   153    coded into a framed OggSquish bitstream by the second layer (see
   154    docs/framing.txt).  Decode is the reverse process; we sync/frame
   155    the bitstream and extract individual packets, then decode the
   156    packet back into PCM audio.
   157 
   158    The extra framing/packetizing is used in streaming formats, such as
   159    files.  Over the net (such as with UDP), the framing and
   160    packetization aren't necessary as they're provided by the transport
   161    and the streaming layer is not used */
   162 
   163 /* Vorbis PRIMITIVES: general ***************************************/
   164 
   165 extern void     vorbis_info_init(vorbis_info *vi);
   166 extern void     vorbis_info_clear(vorbis_info *vi);
   167 extern int      vorbis_info_blocksize(vorbis_info *vi,int zo);
   168 extern void     vorbis_comment_init(vorbis_comment *vc);
   169 extern void     vorbis_comment_add(vorbis_comment *vc, const char *comment);
   170 extern void     vorbis_comment_add_tag(vorbis_comment *vc,
   171                                        const char *tag, const char *contents);
   172 extern char    *vorbis_comment_query(vorbis_comment *vc, const char *tag, int count);
   173 extern int      vorbis_comment_query_count(vorbis_comment *vc, const char *tag);
   174 extern void     vorbis_comment_clear(vorbis_comment *vc);
   175 
   176 extern int      vorbis_block_init(vorbis_dsp_state *v, vorbis_block *vb);
   177 extern int      vorbis_block_clear(vorbis_block *vb);
   178 extern void     vorbis_dsp_clear(vorbis_dsp_state *v);
   179 extern double   vorbis_granule_time(vorbis_dsp_state *v,
   180                                     ogg_int64_t granulepos);
   181 
   182 extern const char *vorbis_version_string(void);
   183 
   184 /* Vorbis PRIMITIVES: analysis/DSP layer ****************************/
   185 
   186 extern int      vorbis_analysis_init(vorbis_dsp_state *v,vorbis_info *vi);
   187 extern int      vorbis_commentheader_out(vorbis_comment *vc, ogg_packet *op);
   188 extern int      vorbis_analysis_headerout(vorbis_dsp_state *v,
   189                                           vorbis_comment *vc,
   190                                           ogg_packet *op,
   191                                           ogg_packet *op_comm,
   192                                           ogg_packet *op_code);
   193 extern float  **vorbis_analysis_buffer(vorbis_dsp_state *v,int vals);
   194 extern int      vorbis_analysis_wrote(vorbis_dsp_state *v,int vals);
   195 extern int      vorbis_analysis_blockout(vorbis_dsp_state *v,vorbis_block *vb);
   196 extern int      vorbis_analysis(vorbis_block *vb,ogg_packet *op);
   197 
   198 extern int      vorbis_bitrate_addblock(vorbis_block *vb);
   199 extern int      vorbis_bitrate_flushpacket(vorbis_dsp_state *vd,
   200                                            ogg_packet *op);
   201 
   202 /* Vorbis PRIMITIVES: synthesis layer *******************************/
   203 extern int      vorbis_synthesis_idheader(ogg_packet *op);
   204 extern int      vorbis_synthesis_headerin(vorbis_info *vi,vorbis_comment *vc,
   205                                           ogg_packet *op);
   206 
   207 extern int      vorbis_synthesis_init(vorbis_dsp_state *v,vorbis_info *vi);
   208 extern int      vorbis_synthesis_restart(vorbis_dsp_state *v);
   209 extern int      vorbis_synthesis(vorbis_block *vb,ogg_packet *op);
   210 extern int      vorbis_synthesis_trackonly(vorbis_block *vb,ogg_packet *op);
   211 extern int      vorbis_synthesis_blockin(vorbis_dsp_state *v,vorbis_block *vb);
   212 extern int      vorbis_synthesis_pcmout(vorbis_dsp_state *v,float ***pcm);
   213 extern int      vorbis_synthesis_lapout(vorbis_dsp_state *v,float ***pcm);
   214 extern int      vorbis_synthesis_read(vorbis_dsp_state *v,int samples);
   215 extern long     vorbis_packet_blocksize(vorbis_info *vi,ogg_packet *op);
   216 
   217 extern int      vorbis_synthesis_halfrate(vorbis_info *v,int flag);
   218 extern int      vorbis_synthesis_halfrate_p(vorbis_info *v);
   219 
   220 /* Vorbis ERRORS and return codes ***********************************/
   221 
   222 #define OV_FALSE      -1
   223 #define OV_EOF        -2
   224 #define OV_HOLE       -3
   225 
   226 #define OV_EREAD      -128
   227 #define OV_EFAULT     -129
   228 #define OV_EIMPL      -130
   229 #define OV_EINVAL     -131
   230 #define OV_ENOTVORBIS -132
   231 #define OV_EBADHEADER -133
   232 #define OV_EVERSION   -134
   233 #define OV_ENOTAUDIO  -135
   234 #define OV_EBADPACKET -136
   235 #define OV_EBADLINK   -137
   236 #define OV_ENOSEEK    -138
   237 
   238 #ifdef __cplusplus
   239 }
   240 #endif /* __cplusplus */
   241 
   242 #endif
   243