diff options
Diffstat (limited to 'info.c')
-rw-r--r-- | info.c | 342 |
1 files changed, 342 insertions, 0 deletions
@@ -0,0 +1,342 @@ +/******************************************************************** + * * + * THIS FILE IS PART OF THE OggVorbis 'TREMOR' 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 'TREMOR' SOURCE CODE IS (C) COPYRIGHT 1994-2003 * + * BY THE Xiph.Org FOUNDATION http://www.xiph.org/ * + * * + ******************************************************************** + + function: maintain the info structure, info <-> header packets + + ********************************************************************/ + +/* general handling of the header and the vorbis_info structure (and + substructures) */ + +#include <stdlib.h> +#include <string.h> +#include <ctype.h> +#include "ogg.h" +#include "ivorbiscodec.h" +#include "codec_internal.h" +#include "codebook.h" +#include "misc.h" +#include "os.h" + +/* helpers */ +static void _v_readstring(oggpack_buffer *o,char *buf,int bytes){ + while(bytes--){ + *buf++=oggpack_read(o,8); + } +} + +void vorbis_comment_init(vorbis_comment *vc){ + memset(vc,0,sizeof(*vc)); +} + +/* This is more or less the same as strncasecmp - but that doesn't exist + * everywhere, and this is a fairly trivial function, so we include it */ +static int tagcompare(const char *s1, const char *s2, int n){ + int c=0; + while(c < n){ + if(toupper(s1[c]) != toupper(s2[c])) + return !0; + c++; + } + return 0; +} + +char *vorbis_comment_query(vorbis_comment *vc, char *tag, int count){ + long i; + int found = 0; + int taglen = strlen(tag)+1; /* +1 for the = we append */ + char *fulltag = (char *)alloca(taglen+ 1); + + strcpy(fulltag, tag); + strcat(fulltag, "="); + + for(i=0;i<vc->comments;i++){ + if(!tagcompare(vc->user_comments[i], fulltag, taglen)){ + if(count == found) + /* We return a pointer to the data, not a copy */ + return vc->user_comments[i] + taglen; + else + found++; + } + } + return NULL; /* didn't find anything */ +} + +int vorbis_comment_query_count(vorbis_comment *vc, char *tag){ + int i,count=0; + int taglen = strlen(tag)+1; /* +1 for the = we append */ + char *fulltag = (char *)alloca(taglen+1); + strcpy(fulltag,tag); + strcat(fulltag, "="); + + for(i=0;i<vc->comments;i++){ + if(!tagcompare(vc->user_comments[i], fulltag, taglen)) + count++; + } + + return count; +} + +void vorbis_comment_clear(vorbis_comment *vc){ + if(vc){ + long i; + for(i=0;i<vc->comments;i++) + if(vc->user_comments[i])_ogg_free(vc->user_comments[i]); + if(vc->user_comments)_ogg_free(vc->user_comments); + if(vc->comment_lengths)_ogg_free(vc->comment_lengths); + if(vc->vendor)_ogg_free(vc->vendor); + } + memset(vc,0,sizeof(*vc)); +} + +/* blocksize 0 is guaranteed to be short, 1 is guarantted to be long. + They may be equal, but short will never ge greater than long */ +int vorbis_info_blocksize(vorbis_info *vi,int zo){ + codec_setup_info *ci = (codec_setup_info *)vi->codec_setup; + return ci ? ci->blocksizes[zo] : -1; +} + +/* used by synthesis, which has a full, alloced vi */ +void vorbis_info_init(vorbis_info *vi){ + memset(vi,0,sizeof(*vi)); + vi->codec_setup=(codec_setup_info *)_ogg_calloc(1,sizeof(codec_setup_info)); +} + +void vorbis_info_clear(vorbis_info *vi){ + codec_setup_info *ci=(codec_setup_info *)vi->codec_setup; + int i; + + if(ci){ + + if(ci->mode_param)_ogg_free(ci->mode_param); + + if(ci->map_param){ + for(i=0;i<ci->maps;i++) /* unpack does the range checking */ + mapping_clear_info(ci->map_param+i); + _ogg_free(ci->map_param); + } + + if(ci->floor_param){ + for(i=0;i<ci->floors;i++) /* unpack does the range checking */ + if(ci->floor_type[i]) + floor1_free_info(ci->floor_param[i]); + else + floor0_free_info(ci->floor_param[i]); + _ogg_free(ci->floor_param); + _ogg_free(ci->floor_type); + } + + if(ci->residue_param){ + for(i=0;i<ci->residues;i++) /* unpack does the range checking */ + res_clear_info(ci->residue_param+i); + _ogg_free(ci->residue_param); + } + + if(ci->book_param){ + for(i=0;i<ci->books;i++) + vorbis_book_clear(ci->book_param+i); + _ogg_free(ci->book_param); + } + + _ogg_free(ci); + } + + memset(vi,0,sizeof(*vi)); +} + +/* Header packing/unpacking ********************************************/ + +static int _vorbis_unpack_info(vorbis_info *vi,oggpack_buffer *opb){ + codec_setup_info *ci=(codec_setup_info *)vi->codec_setup; + if(!ci)return(OV_EFAULT); + + vi->version=oggpack_read(opb,32); + if(vi->version!=0)return(OV_EVERSION); + + vi->channels=oggpack_read(opb,8); + vi->rate=oggpack_read(opb,32); + + vi->bitrate_upper=oggpack_read(opb,32); + vi->bitrate_nominal=oggpack_read(opb,32); + vi->bitrate_lower=oggpack_read(opb,32); + + ci->blocksizes[0]=1<<oggpack_read(opb,4); + ci->blocksizes[1]=1<<oggpack_read(opb,4); + + if(vi->rate<1)goto err_out; + if(vi->channels<1)goto err_out; + if(ci->blocksizes[0]<64)goto err_out; + if(ci->blocksizes[1]<ci->blocksizes[0])goto err_out; + if(ci->blocksizes[1]>8192)goto err_out; + + if(oggpack_read(opb,1)!=1)goto err_out; /* EOP check */ + + return(0); + err_out: + vorbis_info_clear(vi); + return(OV_EBADHEADER); +} + +static int _vorbis_unpack_comment(vorbis_comment *vc,oggpack_buffer *opb){ + int i; + int vendorlen=oggpack_read(opb,32); + if(vendorlen<0)goto err_out; + vc->vendor=(char *)_ogg_calloc(vendorlen+1,1); + _v_readstring(opb,vc->vendor,vendorlen); + vc->comments=oggpack_read(opb,32); + if(vc->comments<0)goto err_out; + vc->user_comments=(char **)_ogg_calloc(vc->comments+1,sizeof(*vc->user_comments)); + vc->comment_lengths=(int *)_ogg_calloc(vc->comments+1, sizeof(*vc->comment_lengths)); + + for(i=0;i<vc->comments;i++){ + int len=oggpack_read(opb,32); + if(len<0)goto err_out; + vc->comment_lengths[i]=len; + vc->user_comments[i]=(char *)_ogg_calloc(len+1,1); + _v_readstring(opb,vc->user_comments[i],len); + } + if(oggpack_read(opb,1)!=1)goto err_out; /* EOP check */ + + return(0); + err_out: + vorbis_comment_clear(vc); + return(OV_EBADHEADER); +} + +/* all of the real encoding details are here. The modes, books, + everything */ +static int _vorbis_unpack_books(vorbis_info *vi,oggpack_buffer *opb){ + codec_setup_info *ci=(codec_setup_info *)vi->codec_setup; + int i; + if(!ci)return(OV_EFAULT); + + /* codebooks */ + ci->books=oggpack_read(opb,8)+1; + ci->book_param=(codebook *)_ogg_calloc(ci->books,sizeof(*ci->book_param)); + for(i=0;i<ci->books;i++) + if(vorbis_book_unpack(opb,ci->book_param+i))goto err_out; + + /* time backend settings, not actually used */ + i=oggpack_read(opb,6); + for(;i>=0;i--) + if(oggpack_read(opb,16)!=0)goto err_out; + + /* floor backend settings */ + ci->floors=oggpack_read(opb,6)+1; + ci->floor_param=_ogg_malloc(sizeof(*ci->floor_param)*ci->floors); + ci->floor_type=_ogg_malloc(sizeof(*ci->floor_type)*ci->floors); + for(i=0;i<ci->floors;i++){ + ci->floor_type[i]=oggpack_read(opb,16); + if(ci->floor_type[i]<0 || ci->floor_type[i]>=VI_FLOORB)goto err_out; + if(ci->floor_type[i]) + ci->floor_param[i]=floor1_info_unpack(vi,opb); + else + ci->floor_param[i]=floor0_info_unpack(vi,opb); + if(!ci->floor_param[i])goto err_out; + } + + /* residue backend settings */ + ci->residues=oggpack_read(opb,6)+1; + ci->residue_param=_ogg_malloc(sizeof(*ci->residue_param)*ci->residues); + for(i=0;i<ci->residues;i++) + if(res_unpack(ci->residue_param+i,vi,opb))goto err_out; + + /* map backend settings */ + ci->maps=oggpack_read(opb,6)+1; + ci->map_param=_ogg_malloc(sizeof(*ci->map_param)*ci->maps); + for(i=0;i<ci->maps;i++){ + if(oggpack_read(opb,16)!=0)goto err_out; + if(mapping_info_unpack(ci->map_param+i,vi,opb))goto err_out; + } + + /* mode settings */ + ci->modes=oggpack_read(opb,6)+1; + ci->mode_param= + (vorbis_info_mode *)_ogg_malloc(ci->modes*sizeof(*ci->mode_param)); + for(i=0;i<ci->modes;i++){ + ci->mode_param[i].blockflag=oggpack_read(opb,1); + if(oggpack_read(opb,16))goto err_out; + if(oggpack_read(opb,16))goto err_out; + ci->mode_param[i].mapping=oggpack_read(opb,8); + if(ci->mode_param[i].mapping>=ci->maps)goto err_out; + } + + if(oggpack_read(opb,1)!=1)goto err_out; /* top level EOP check */ + + return(0); + err_out: + vorbis_info_clear(vi); + return(OV_EBADHEADER); +} + +/* The Vorbis header is in three packets; the initial small packet in + the first page that identifies basic parameters, a second packet + with bitstream comments and a third packet that holds the + codebook. */ + +int vorbis_dsp_headerin(vorbis_info *vi,vorbis_comment *vc,ogg_packet *op){ + oggpack_buffer opb; + + if(op){ + oggpack_readinit(&opb,op->packet); + + /* Which of the three types of header is this? */ + /* Also verify header-ness, vorbis */ + { + char buffer[6]; + int packtype=oggpack_read(&opb,8); + memset(buffer,0,6); + _v_readstring(&opb,buffer,6); + if(memcmp(buffer,"vorbis",6)){ + /* not a vorbis header */ + return(OV_ENOTVORBIS); + } + switch(packtype){ + case 0x01: /* least significant *bit* is read first */ + if(!op->b_o_s){ + /* Not the initial packet */ + return(OV_EBADHEADER); + } + if(vi->rate!=0){ + /* previously initialized info header */ + return(OV_EBADHEADER); + } + + return(_vorbis_unpack_info(vi,&opb)); + + case 0x03: /* least significant *bit* is read first */ + if(vi->rate==0){ + /* um... we didn't get the initial header */ + return(OV_EBADHEADER); + } + + return(_vorbis_unpack_comment(vc,&opb)); + + case 0x05: /* least significant *bit* is read first */ + if(vi->rate==0 || vc->vendor==NULL){ + /* um... we didn;t get the initial header or comments yet */ + return(OV_EBADHEADER); + } + + return(_vorbis_unpack_books(vi,&opb)); + + default: + /* Not a valid vorbis header type */ + return(OV_EBADHEADER); + break; + } + } + } + return(OV_EBADHEADER); +} + |