codec.h (8387B)
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 https://xiph.org/ * 10 11 ******************************************************************** 12 13 function: libvorbis codec headers 14 15 ********************************************************************/ 16 17 #ifndef _vorbis_codec_h_ 18 #define _vorbis_codec_h_ 19 20 #ifdef __cplusplus 21 extern "C" 22 { 23 #endif /* __cplusplus */ 24 25 #include <ogg/ogg.h> 26 27 typedef struct vorbis_info{ 28 int version; 29 int channels; 30 long rate; 31 32 /* The below bitrate declarations are *hints*. 33 Combinations of the three values carry the following implications: 34 35 all three set to the same value: 36 implies a fixed rate bitstream 37 only nominal set: 38 implies a VBR stream that averages the nominal bitrate. No hard 39 upper/lower limit 40 upper and or lower set: 41 implies a VBR bitstream that obeys the bitrate limits. nominal 42 may also be set to give a nominal rate. 43 none set: 44 the coder does not care to speculate. 45 */ 46 47 long bitrate_upper; 48 long bitrate_nominal; 49 long bitrate_lower; 50 long bitrate_window; 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 int analysisp; 60 vorbis_info *vi; 61 62 float **pcm; 63 float **pcmret; 64 int pcm_storage; 65 int pcm_current; 66 int pcm_returned; 67 68 int preextrapolate; 69 int eofflag; 70 71 long lW; 72 long W; 73 long nW; 74 long centerW; 75 76 ogg_int64_t granulepos; 77 ogg_int64_t sequence; 78 79 ogg_int64_t glue_bits; 80 ogg_int64_t time_bits; 81 ogg_int64_t floor_bits; 82 ogg_int64_t res_bits; 83 84 void *backend_state; 85 } vorbis_dsp_state; 86 87 typedef struct vorbis_block{ 88 /* necessary stream state for linking to the framing abstraction */ 89 float **pcm; /* this is a pointer into local storage */ 90 oggpack_buffer opb; 91 92 long lW; 93 long W; 94 long nW; 95 int pcmend; 96 int mode; 97 98 int eofflag; 99 ogg_int64_t granulepos; 100 ogg_int64_t sequence; 101 vorbis_dsp_state *vd; /* For read-only access of configuration */ 102 103 /* local storage to avoid remallocing; it's up to the mapping to 104 structure it */ 105 void *localstore; 106 long localtop; 107 long localalloc; 108 long totaluse; 109 struct alloc_chain *reap; 110 111 /* bitmetrics for the frame */ 112 long glue_bits; 113 long time_bits; 114 long floor_bits; 115 long res_bits; 116 117 void *internal; 118 119 } vorbis_block; 120 121 /* vorbis_block is a single block of data to be processed as part of 122 the analysis/synthesis stream; it belongs to a specific logical 123 bitstream, but is independent from other vorbis_blocks belonging to 124 that logical bitstream. *************************************************/ 125 126 struct alloc_chain{ 127 void *ptr; 128 struct alloc_chain *next; 129 }; 130 131 /* vorbis_info contains all the setup information specific to the 132 specific compression/decompression mode in progress (eg, 133 psychoacoustic settings, channel setup, options, codebook 134 etc). vorbis_info and substructures are in backends.h. 135 *********************************************************************/ 136 137 /* the comments are not part of vorbis_info so that vorbis_info can be 138 static storage */ 139 typedef struct vorbis_comment{ 140 /* unlimited user comment fields. libvorbis writes 'libvorbis' 141 whatever vendor is set to in encode */ 142 char **user_comments; 143 int *comment_lengths; 144 int comments; 145 char *vendor; 146 147 } vorbis_comment; 148 149 150 /* libvorbis encodes in two abstraction layers; first we perform DSP 151 and produce a packet (see docs/analysis.txt). The packet is then 152 coded into a framed OggSquish bitstream by the second layer (see 153 docs/framing.txt). Decode is the reverse process; we sync/frame 154 the bitstream and extract individual packets, then decode the 155 packet back into PCM audio. 156 157 The extra framing/packetizing is used in streaming formats, such as 158 files. Over the net (such as with UDP), the framing and 159 packetization aren't necessary as they're provided by the transport 160 and the streaming layer is not used */ 161 162 /* Vorbis PRIMITIVES: general ***************************************/ 163 164 extern void vorbis_info_init(vorbis_info *vi); 165 extern void vorbis_info_clear(vorbis_info *vi); 166 extern int vorbis_info_blocksize(vorbis_info *vi,int zo); 167 extern void vorbis_comment_init(vorbis_comment *vc); 168 extern void vorbis_comment_add(vorbis_comment *vc, const char *comment); 169 extern void vorbis_comment_add_tag(vorbis_comment *vc, 170 const char *tag, const char *contents); 171 extern char *vorbis_comment_query(vorbis_comment *vc, const char *tag, int count); 172 extern int vorbis_comment_query_count(vorbis_comment *vc, const char *tag); 173 extern void vorbis_comment_clear(vorbis_comment *vc); 174 175 extern int vorbis_block_init(vorbis_dsp_state *v, vorbis_block *vb); 176 extern int vorbis_block_clear(vorbis_block *vb); 177 extern void vorbis_dsp_clear(vorbis_dsp_state *v); 178 extern double vorbis_granule_time(vorbis_dsp_state *v, 179 ogg_int64_t granulepos); 180 181 extern const char *vorbis_version_string(void); 182 183 /* Vorbis PRIMITIVES: analysis/DSP layer ****************************/ 184 185 extern int vorbis_analysis_init(vorbis_dsp_state *v,vorbis_info *vi); 186 extern int vorbis_commentheader_out(vorbis_comment *vc, ogg_packet *op); 187 extern int vorbis_analysis_headerout(vorbis_dsp_state *v, 188 vorbis_comment *vc, 189 ogg_packet *op, 190 ogg_packet *op_comm, 191 ogg_packet *op_code); 192 extern float **vorbis_analysis_buffer(vorbis_dsp_state *v,int vals); 193 extern int vorbis_analysis_wrote(vorbis_dsp_state *v,int vals); 194 extern int vorbis_analysis_blockout(vorbis_dsp_state *v,vorbis_block *vb); 195 extern int vorbis_analysis(vorbis_block *vb,ogg_packet *op); 196 197 extern int vorbis_bitrate_addblock(vorbis_block *vb); 198 extern int vorbis_bitrate_flushpacket(vorbis_dsp_state *vd, 199 ogg_packet *op); 200 201 /* Vorbis PRIMITIVES: synthesis layer *******************************/ 202 extern int vorbis_synthesis_idheader(ogg_packet *op); 203 extern int vorbis_synthesis_headerin(vorbis_info *vi,vorbis_comment *vc, 204 ogg_packet *op); 205 206 extern int vorbis_synthesis_init(vorbis_dsp_state *v,vorbis_info *vi); 207 extern int vorbis_synthesis_restart(vorbis_dsp_state *v); 208 extern int vorbis_synthesis(vorbis_block *vb,ogg_packet *op); 209 extern int vorbis_synthesis_trackonly(vorbis_block *vb,ogg_packet *op); 210 extern int vorbis_synthesis_blockin(vorbis_dsp_state *v,vorbis_block *vb); 211 extern int vorbis_synthesis_pcmout(vorbis_dsp_state *v,float ***pcm); 212 extern int vorbis_synthesis_lapout(vorbis_dsp_state *v,float ***pcm); 213 extern int vorbis_synthesis_read(vorbis_dsp_state *v,int samples); 214 extern long vorbis_packet_blocksize(vorbis_info *vi,ogg_packet *op); 215 216 extern int vorbis_synthesis_halfrate(vorbis_info *v,int flag); 217 extern int vorbis_synthesis_halfrate_p(vorbis_info *v); 218 219 /* Vorbis ERRORS and return codes ***********************************/ 220 221 #define OV_FALSE -1 222 #define OV_EOF -2 223 #define OV_HOLE -3 224 225 #define OV_EREAD -128 226 #define OV_EFAULT -129 227 #define OV_EIMPL -130 228 #define OV_EINVAL -131 229 #define OV_ENOTVORBIS -132 230 #define OV_EBADHEADER -133 231 #define OV_EVERSION -134 232 #define OV_ENOTAUDIO -135 233 #define OV_EBADPACKET -136 234 #define OV_EBADLINK -137 235 #define OV_ENOSEEK -138 236 237 #ifdef __cplusplus 238 } 239 #endif /* __cplusplus */ 240 241 #endif