codec.h (8059B)
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 XIPHOPHORUS Company http://www.xiph.org/ * 10 11 ******************************************************************** 12 13 function: libvorbis codec headers 14 last mod: $Id: codec.h 1919 2005-07-24 14:18:04Z baford $ 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, char *comment); 170 extern void vorbis_comment_add_tag(vorbis_comment *vc, 171 char *tag, char *contents); 172 extern char *vorbis_comment_query(vorbis_comment *vc, char *tag, int count); 173 extern int vorbis_comment_query_count(vorbis_comment *vc, 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 /* Vorbis PRIMITIVES: analysis/DSP layer ****************************/ 183 184 extern int vorbis_analysis_init(vorbis_dsp_state *v,vorbis_info *vi); 185 extern int vorbis_commentheader_out(vorbis_comment *vc, ogg_packet *op); 186 extern int vorbis_analysis_headerout(vorbis_dsp_state *v, 187 vorbis_comment *vc, 188 ogg_packet *op, 189 ogg_packet *op_comm, 190 ogg_packet *op_code); 191 extern float **vorbis_analysis_buffer(vorbis_dsp_state *v,int vals); 192 extern int vorbis_analysis_wrote(vorbis_dsp_state *v,int vals); 193 extern int vorbis_analysis_blockout(vorbis_dsp_state *v,vorbis_block *vb); 194 extern int vorbis_analysis(vorbis_block *vb,ogg_packet *op); 195 196 extern int vorbis_bitrate_addblock(vorbis_block *vb); 197 extern int vorbis_bitrate_flushpacket(vorbis_dsp_state *vd, 198 ogg_packet *op); 199 200 /* Vorbis PRIMITIVES: synthesis layer *******************************/ 201 extern int vorbis_synthesis_headerin(vorbis_info *vi,vorbis_comment *vc, 202 ogg_packet *op); 203 204 extern int vorbis_synthesis_init(vorbis_dsp_state *v,vorbis_info *vi); 205 extern int vorbis_synthesis_restart(vorbis_dsp_state *v); 206 extern int vorbis_synthesis(vorbis_block *vb,ogg_packet *op); 207 extern int vorbis_synthesis_trackonly(vorbis_block *vb,ogg_packet *op); 208 extern int vorbis_synthesis_blockin(vorbis_dsp_state *v,vorbis_block *vb); 209 extern int vorbis_synthesis_pcmout(vorbis_dsp_state *v,float ***pcm); 210 extern int vorbis_synthesis_lapout(vorbis_dsp_state *v,float ***pcm); 211 extern int vorbis_synthesis_read(vorbis_dsp_state *v,int samples); 212 extern long vorbis_packet_blocksize(vorbis_info *vi,ogg_packet *op); 213 214 extern int vorbis_synthesis_halfrate(vorbis_info *v,int flag); 215 extern int vorbis_synthesis_halfrate_p(vorbis_info *v); 216 217 /* Vorbis ERRORS and return codes ***********************************/ 218 219 #define OV_FALSE -1 220 #define OV_EOF -2 221 #define OV_HOLE -3 222 223 #define OV_EREAD -128 224 #define OV_EFAULT -129 225 #define OV_EIMPL -130 226 #define OV_EINVAL -131 227 #define OV_ENOTVORBIS -132 228 #define OV_EBADHEADER -133 229 #define OV_EVERSION -134 230 #define OV_ENOTAUDIO -135 231 #define OV_EBADPACKET -136 232 #define OV_EBADLINK -137 233 #define OV_ENOSEEK -138 234 235 #ifdef __cplusplus 236 } 237 #endif /* __cplusplus */ 238 239 #endif 240