ref: e16e2544cc2987a7931961fa48e145d69e9e9ff8
dir: /src/sf.c/
/* * July 5, 1991 * Copyright 1991 Lance Norskog And Sundry Contributors * This source code is freely redistributable and may be used for * any purpose. This copyright notice must be maintained. * Lance Norskog And Sundry Contributors are not responsible for * the consequences of using this software. */ /* * Sound Tools IRCAM SoundFile format handler. * * Derived from: Sound Tools skeleton handler file. */ #include "st_i.h" #include "sfircam.h" #ifndef SIZEOF_BSD_HEADER #define SIZEOF_BSD_HEADER 1024 #endif #include <string.h> #include <stdlib.h> /* Private data for SF file */ typedef struct sfstuff { struct sfinfo info; /* needed for seek */ st_size_t dataStart; } *sf_t; /* * Read the codes from the sound file, allocate space for the comment and * assign its pointer to the comment field in ft. */ static void readcodes(ft_t ft, SFHEADER *sfhead) { char *commentbuf = NULL, *sfcharp, *newline; short bsize, finished = 0; SFCODE *sfcodep; sfcodep = (SFCODE *) &sfcodes(sfhead); do { sfcharp = (char *) sfcodep + sizeof(SFCODE); if (ft->swap) { sfcodep->bsize = st_swapdw(sfcodep->bsize); sfcodep->code = st_swapdw(sfcodep->code); } bsize = sfcodep->bsize - sizeof(SFCODE); switch(sfcodep->code) { case SF_END: finished = 1; break; case SF_COMMENT: if((commentbuf = (char *) malloc(bsize + 1)) != NULL) { memcpy(commentbuf, sfcharp, bsize); st_report("IRCAM comment: %s", sfcharp); commentbuf[bsize] = '\0'; if((newline = strchr(commentbuf, '\n')) != NULL) *newline = '\0'; } break; } sfcodep = (SFCODE *) (sfcharp + bsize); } while(!finished); if(commentbuf != NULL) /* handles out of memory condition as well */ ft->comment = commentbuf; } int st_sfseek(ft_t ft, st_size_t offset) { st_size_t new_offset, channel_block, alignment; sf_t sf = (sf_t ) ft->priv; new_offset = offset * ft->info.size; /* Make sure request aligns to a channel block (ie left+right) */ channel_block = ft->info.channels * ft->info.size; alignment = new_offset % channel_block; /* Most common mistaken is to compute something like * "skip everthing upto and including this sample" so * advance to next sample block in this case. */ if (alignment != 0) new_offset += (channel_block - alignment); new_offset += sf->dataStart; return st_seek(ft, new_offset, SEEK_SET); } /* * Do anything required before you start reading samples. * Read file header. * Find out sampling rate, * size and encoding of samples, * mono/stereo/quad. */ int st_sfstartread(ft_t ft) { sf_t sf = (sf_t) ft->priv; SFHEADER sfhead; int rc; int samplesize = 0; if (st_read(ft, &sfhead, 1, sizeof(sfhead)) != sizeof(sfhead)) { st_fail("unexpected EOF in SF header"); return(ST_EOF); } memcpy(&sf->info, &sfhead.sfinfo, sizeof(struct sfinfo)); if (ft->swap) { sf->info.sf_srate = st_swapf(sf->info.sf_srate); sf->info.sf_packmode = st_swapdw(sf->info.sf_packmode); sf->info.sf_chans = st_swapdw(sf->info.sf_chans); } if ((sfmagic1(&sfhead) != SF_MAGIC1) || (sfmagic2(&sfhead) != SF_MAGIC2)) st_fail( "SF %s file: can't read, it is byte-swapped or it is not an IRCAM SoundFile", ft->filename); /* * If your format specifies or your file header contains * any of the following information. */ ft->info.rate = sf->info.sf_srate; switch(sf->info.sf_packmode) { case SF_SHORT: ft->info.size = ST_SIZE_WORD; ft->info.encoding = ST_ENCODING_SIGN2; samplesize = ft->info.size; break; case SF_FLOAT: ft->info.size = ST_SIZE_DWORD; ft->info.encoding = ST_ENCODING_FLOAT; samplesize = sizeof(float); break; default: st_fail("Soundfile input: unknown format 0x%x\n", sf->info.sf_packmode); return(ST_EOF); } ft->info.channels = (int) sf->info.sf_chans; if (ft->info.channels == -1) ft->info.channels = 1; /* Read codes and print as comments. */ readcodes(ft, &sfhead); /* Needed for rawread() */ rc = st_rawstartread(ft); /* Need length for seeking */ if(ft->seekable){ ft->length = st_filelength(ft)/samplesize; sf->dataStart = st_tell(ft); } else { ft->length = 0; } return(rc); } int st_sfstartwrite(ft_t ft) { sf_t sf = (sf_t) ft->priv; SFHEADER sfhead; SFCODE *sfcodep; char *sfcharp; int rc; /* Needed for rawwrite() */ rc = st_rawstartwrite(ft); if (rc) return rc; sf->info.magic_union._magic_bytes.sf_magic1 = SF_MAGIC1; sf->info.magic_union._magic_bytes.sf_magic2 = SF_MAGIC2; sf->info.magic_union._magic_bytes.sf_param = 0; /* This file handler can handle both big and little endian data */ if (ST_IS_LITTLEENDIAN) sf->info.magic_union._magic_bytes.sf_machine = SF_VAX; else sf->info.magic_union._magic_bytes.sf_machine = SF_SUN; sf->info.sf_srate = ft->info.rate; if (ft->info.size == ST_SIZE_DWORD && ft->info.encoding == ST_ENCODING_FLOAT) { sf->info.sf_packmode = SF_FLOAT; } else { sf->info.sf_packmode = SF_SHORT; /* Default to signed words */ ft->info.size = ST_SIZE_WORD; ft->info.encoding = ST_ENCODING_SIGN2; } sf->info.sf_chans = ft->info.channels; /* Clean out structure so unused areas will remain constain */ /* between different coverts and not rely on memory contents */ memset (&sfhead, 0, sizeof(SFHEADER)); memcpy(&sfhead.sfinfo, &sf->info, sizeof(struct sfinfo)); sfcodep = (SFCODE *) &sfcodes(&sfhead); sfcodep->code = SF_COMMENT; sfcodep->bsize = strlen(ft->comment) + sizeof(SFCODE); while (sfcodep->bsize % 4) sfcodep->bsize++; sfcharp = (char *) sfcodep; strcpy(sfcharp + sizeof(SFCODE), ft->comment); sfcodep = (SFCODE *) (sfcharp + sfcodep->bsize); sfcodep->code = SF_END; sfcodep->bsize = sizeof(SFCODE); sfcharp = (char *) sfcodep + sizeof(SFCODE); while(sfcharp < (char *) &sfhead + SIZEOF_BSD_HEADER) *sfcharp++ = '\0'; st_write(ft, &sfhead, 1, sizeof(SFHEADER)); return(ST_SUCCESS); } /* Read and write are supplied by raw.c */