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Diffstat (limited to 'include/vorbis/codec.h')
| -rw-r--r-- | include/vorbis/codec.h | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/include/vorbis/codec.h b/include/vorbis/codec.h new file mode 100644 index 0000000..42aa291 --- /dev/null +++ b/include/vorbis/codec.h @@ -0,0 +1,242 @@ +/******************************************************************** + * * + * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. * + * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS * + * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE * + * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. * + * * + * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2001 * + * by the Xiph.Org Foundation http://www.xiph.org/ * + + ******************************************************************** + + function: libvorbis codec headers + + ********************************************************************/ + +#ifndef _vorbis_codec_h_ +#define _vorbis_codec_h_ + +#ifdef __cplusplus +extern "C" +{ +#endif /* __cplusplus */ + +#include <ogg/ogg.h> + +typedef struct vorbis_info{ + int version; + int channels; + long rate; + + /* The below bitrate declarations are *hints*. + Combinations of the three values carry the following implications: + + all three set to the same value: + implies a fixed rate bitstream + only nominal set: + implies a VBR stream that averages the nominal bitrate. No hard + upper/lower limit + upper and or lower set: + implies a VBR bitstream that obeys the bitrate limits. nominal + may also be set to give a nominal rate. + none set: + the coder does not care to speculate. + */ + + long bitrate_upper; + long bitrate_nominal; + long bitrate_lower; + long bitrate_window; + + void *codec_setup; +} vorbis_info; + +/* vorbis_dsp_state buffers the current vorbis audio + analysis/synthesis state. The DSP state belongs to a specific + logical bitstream ****************************************************/ +typedef struct vorbis_dsp_state{ + int analysisp; + vorbis_info *vi; + + float **pcm; + float **pcmret; + int pcm_storage; + int pcm_current; + int pcm_returned; + + int preextrapolate; + int eofflag; + + long lW; + long W; + long nW; + long centerW; + + ogg_int64_t granulepos; + ogg_int64_t sequence; + + ogg_int64_t glue_bits; + ogg_int64_t time_bits; + ogg_int64_t floor_bits; + ogg_int64_t res_bits; + + void *backend_state; +} vorbis_dsp_state; + +typedef struct vorbis_block{ + /* necessary stream state for linking to the framing abstraction */ + float **pcm; /* this is a pointer into local storage */ + oggpack_buffer opb; + + long lW; + long W; + long nW; + int pcmend; + int mode; + + int eofflag; + ogg_int64_t granulepos; + ogg_int64_t sequence; + vorbis_dsp_state *vd; /* For read-only access of configuration */ + + /* local storage to avoid remallocing; it's up to the mapping to + structure it */ + void *localstore; + long localtop; + long localalloc; + long totaluse; + struct alloc_chain *reap; + + /* bitmetrics for the frame */ + long glue_bits; + long time_bits; + long floor_bits; + long res_bits; + + void *internal; + +} vorbis_block; + +/* vorbis_block is a single block of data to be processed as part of +the analysis/synthesis stream; it belongs to a specific logical +bitstream, but is independent from other vorbis_blocks belonging to +that logical bitstream. *************************************************/ + +struct alloc_chain{ + void *ptr; + struct alloc_chain *next; +}; + +/* vorbis_info contains all the setup information specific to the + specific compression/decompression mode in progress (eg, + psychoacoustic settings, channel setup, options, codebook + etc). vorbis_info and substructures are in backends.h. +*********************************************************************/ + +/* the comments are not part of vorbis_info so that vorbis_info can be + static storage */ +typedef struct vorbis_comment{ + /* unlimited user comment fields. libvorbis writes 'libvorbis' + whatever vendor is set to in encode */ + char **user_comments; + int *comment_lengths; + int comments; + char *vendor; + +} vorbis_comment; + + +/* libvorbis encodes in two abstraction layers; first we perform DSP + and produce a packet (see docs/analysis.txt). The packet is then + coded into a framed OggSquish bitstream by the second layer (see + docs/framing.txt). Decode is the reverse process; we sync/frame + the bitstream and extract individual packets, then decode the + packet back into PCM audio. + + The extra framing/packetizing is used in streaming formats, such as + files. Over the net (such as with UDP), the framing and + packetization aren't necessary as they're provided by the transport + and the streaming layer is not used */ + +/* Vorbis PRIMITIVES: general ***************************************/ + +extern void vorbis_info_init(vorbis_info *vi); +extern void vorbis_info_clear(vorbis_info *vi); +extern int vorbis_info_blocksize(vorbis_info *vi,int zo); +extern void vorbis_comment_init(vorbis_comment *vc); +extern void vorbis_comment_add(vorbis_comment *vc, const char *comment); +extern void vorbis_comment_add_tag(vorbis_comment *vc, + const char *tag, const char *contents); +extern char *vorbis_comment_query(vorbis_comment *vc, const char *tag, int count); +extern int vorbis_comment_query_count(vorbis_comment *vc, const char *tag); +extern void vorbis_comment_clear(vorbis_comment *vc); + +extern int vorbis_block_init(vorbis_dsp_state *v, vorbis_block *vb); +extern int vorbis_block_clear(vorbis_block *vb); +extern void vorbis_dsp_clear(vorbis_dsp_state *v); +extern double vorbis_granule_time(vorbis_dsp_state *v, + ogg_int64_t granulepos); + +extern const char *vorbis_version_string(void); + +/* Vorbis PRIMITIVES: analysis/DSP layer ****************************/ + +extern int vorbis_analysis_init(vorbis_dsp_state *v,vorbis_info *vi); +extern int vorbis_commentheader_out(vorbis_comment *vc, ogg_packet *op); +extern int vorbis_analysis_headerout(vorbis_dsp_state *v, + vorbis_comment *vc, + ogg_packet *op, + ogg_packet *op_comm, + ogg_packet *op_code); +extern float **vorbis_analysis_buffer(vorbis_dsp_state *v,int vals); +extern int vorbis_analysis_wrote(vorbis_dsp_state *v,int vals); +extern int vorbis_analysis_blockout(vorbis_dsp_state *v,vorbis_block *vb); +extern int vorbis_analysis(vorbis_block *vb,ogg_packet *op); + +extern int vorbis_bitrate_addblock(vorbis_block *vb); +extern int vorbis_bitrate_flushpacket(vorbis_dsp_state *vd, + ogg_packet *op); + +/* Vorbis PRIMITIVES: synthesis layer *******************************/ +extern int vorbis_synthesis_idheader(ogg_packet *op); +extern int vorbis_synthesis_headerin(vorbis_info *vi,vorbis_comment *vc, + ogg_packet *op); + +extern int vorbis_synthesis_init(vorbis_dsp_state *v,vorbis_info *vi); +extern int vorbis_synthesis_restart(vorbis_dsp_state *v); +extern int vorbis_synthesis(vorbis_block *vb,ogg_packet *op); +extern int vorbis_synthesis_trackonly(vorbis_block *vb,ogg_packet *op); +extern int vorbis_synthesis_blockin(vorbis_dsp_state *v,vorbis_block *vb); +extern int vorbis_synthesis_pcmout(vorbis_dsp_state *v,float ***pcm); +extern int vorbis_synthesis_lapout(vorbis_dsp_state *v,float ***pcm); +extern int vorbis_synthesis_read(vorbis_dsp_state *v,int samples); +extern long vorbis_packet_blocksize(vorbis_info *vi,ogg_packet *op); + +extern int vorbis_synthesis_halfrate(vorbis_info *v,int flag); +extern int vorbis_synthesis_halfrate_p(vorbis_info *v); + +/* Vorbis ERRORS and return codes ***********************************/ + +#define OV_FALSE -1 +#define OV_EOF -2 +#define OV_HOLE -3 + +#define OV_EREAD -128 +#define OV_EFAULT -129 +#define OV_EIMPL -130 +#define OV_EINVAL -131 +#define OV_ENOTVORBIS -132 +#define OV_EBADHEADER -133 +#define OV_EVERSION -134 +#define OV_ENOTAUDIO -135 +#define OV_EBADPACKET -136 +#define OV_EBADLINK -137 +#define OV_ENOSEEK -138 + +#ifdef __cplusplus +} +#endif /* __cplusplus */ + +#endif + |