ref: 400d05369b02b737b3b9e2867a171a7f86649ad1
dir: /src/smp.c/
/* * June 30, 1992 * Copyright 1992 Leigh Smith And Sundry Contributors * This source code is freely redistributable and may be used for * any purpose. This copyright notice must be maintained. * Leigh Smith And Sundry Contributors are not responsible for * the consequences of using this software. */ /* * Sound Tools SampleVision file format driver. * Output is always in little-endian (80x86/VAX) order. * * Derived from: Sound Tools skeleton handler file. * * Add: Loop point verbose info. It's a start, anyway. */ #include "st_i.h" #include <string.h> #ifdef HAVE_ERRNO_H #include <errno.h> #endif #define NAMELEN 30 /* Size of Samplevision name */ #define COMMENTLEN 60 /* Size of Samplevision comment, not shared */ #define MIDI_UNITY 60 /* MIDI note number to play sample at unity */ #define MARKERLEN 10 /* Size of Marker name */ /* The header preceeding the sample data */ struct smpheader { char Id[18]; /* File identifier */ char version[4]; /* File version */ char comments[COMMENTLEN]; /* User comments */ char name[NAMELEN + 1]; /* Sample Name, left justified */ }; #define HEADERSIZE (sizeof(struct smpheader) - 1) /* -1 for name's \0 */ /* Samplevision loop definition structure */ struct loop { uint32_t start; /* Sample count into sample data, not byte count */ uint32_t end; /* end point */ char type; /* 0 = loop off, 1 = forward, 2 = forw/back */ short count; /* No of times to loop */ }; /* Samplevision marker definition structure */ struct marker { char name[MARKERLEN + 1]; /* Ascii Marker name */ uint32_t position; /* Sample Number, not byte number */ }; /* The trailer following the sample data */ struct smptrailer { struct loop loops[8]; /* loops */ struct marker markers[8]; /* markers */ char MIDInote; /* for unity pitch playback */ uint32_t rate; /* in hertz */ uint32_t SMPTEoffset; /* in subframes - huh? */ uint32_t CycleSize; /* sample count in one cycle of the */ /* sampled sound -1 if unknown */ }; /* Private data for SMP file */ typedef struct smpstuff { uint32_t NoOfSamps; /* Sample data count in words */ st_size_t dataStart; /* comment memory resides in private data because it's small */ char comment[COMMENTLEN + NAMELEN + 3]; } *smp_t; char *SVmagic = "SOUND SAMPLE DATA ", *SVvers = "2.1 "; /* * Read the SampleVision trailer structure. * Returns 1 if everything was read ok, 0 if there was an error. */ static int readtrailer(ft_t ft, struct smptrailer *trailer) { int i; int16_t trash16; st_readw(ft, (unsigned short *)&trash16); /* read reserved word */ for(i = 0; i < 8; i++) { /* read the 8 loops */ st_readdw(ft, &(trailer->loops[i].start)); ft->loops[i].start = trailer->loops[i].start; st_readdw(ft, &(trailer->loops[i].end)); ft->loops[i].length = trailer->loops[i].end - trailer->loops[i].start; st_readb(ft, (unsigned char *)&(trailer->loops[i].type)); ft->loops[i].type = trailer->loops[i].type; st_readw(ft, (unsigned short *)&(trailer->loops[i].count)); ft->loops[i].count = trailer->loops[i].count; } for(i = 0; i < 8; i++) { /* read the 8 markers */ if (st_readbuf(ft, trailer->markers[i].name, 1, MARKERLEN) != 10) { st_fail_errno(ft,ST_EHDR,"EOF in SMP"); return(ST_EOF); } trailer->markers[i].name[MARKERLEN] = 0; st_readdw(ft, &(trailer->markers[i].position)); } st_readb(ft, (unsigned char *)&(trailer->MIDInote)); st_readdw(ft, &(trailer->rate)); st_readdw(ft, &(trailer->SMPTEoffset)); st_readdw(ft, &(trailer->CycleSize)); return(ST_SUCCESS); } /* * set the trailer data - loops and markers, to reasonably benign values */ static void settrailer(ft_t ft, struct smptrailer *trailer, st_rate_t rate) { int i; for(i = 0; i < 8; i++) { /* copy the 8 loops */ if (ft->loops[i].type != 0) { trailer->loops[i].start = ft->loops[i].start; /* to mark it as not set */ trailer->loops[i].end = ft->loops[i].start + ft->loops[i].length; trailer->loops[i].type = ft->loops[i].type; trailer->loops[i].count = ft->loops[i].count; } else { /* set first loop start as FFFFFFFF */ trailer->loops[i].start = ~0; /* to mark it as not set */ trailer->loops[i].end = 0; trailer->loops[i].type = 0; trailer->loops[i].count = 0; } } for(i = 0; i < 8; i++) { /* write the 8 markers */ strcpy(trailer->markers[i].name, " "); trailer->markers[i].position = ~0; } trailer->MIDInote = MIDI_UNITY; /* Unity play back */ trailer->rate = rate; trailer->SMPTEoffset = 0; trailer->CycleSize = -1; } /* * Write the SampleVision trailer structure. * Returns 1 if everything was written ok, 0 if there was an error. */ static int writetrailer(ft_t ft, struct smptrailer *trailer) { int i; st_writew(ft, 0); /* write the reserved word */ for(i = 0; i < 8; i++) { /* write the 8 loops */ st_writedw(ft, trailer->loops[i].start); st_writedw(ft, trailer->loops[i].end); st_writeb(ft, trailer->loops[i].type); st_writew(ft, trailer->loops[i].count); } for(i = 0; i < 8; i++) { /* write the 8 markers */ if (st_writes(ft, trailer->markers[i].name) == ST_EOF) { st_fail_errno(ft,ST_EHDR,"EOF in SMP"); return(ST_EOF); } st_writedw(ft, trailer->markers[i].position); } st_writeb(ft, trailer->MIDInote); st_writedw(ft, trailer->rate); st_writedw(ft, trailer->SMPTEoffset); st_writedw(ft, trailer->CycleSize); return(ST_SUCCESS); } int st_smpseek(ft_t ft, st_size_t offset) { int new_offset, channel_block, alignment; smp_t smp = (smp_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 += smp->dataStart; ft->st_errno = st_seeki(ft, new_offset, SEEK_SET); if( ft->st_errno == ST_SUCCESS ) smp->NoOfSamps = ft->length - (new_offset / ft->info.size); return(ft->st_errno); } /* * 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_smpstartread(ft_t ft) { smp_t smp = (smp_t) ft->priv; int i; int namelen, commentlen; long samplestart; struct smpheader header; struct smptrailer trailer; /* SMP is in Little Endian format. Swap whats read in on */ /* Big Endian machines. */ if (ST_IS_BIGENDIAN) { ft->swap = ft->swap ? 0 : 1; } /* If you need to seek around the input file. */ if (! ft->seekable) { st_fail_errno(ft,ST_EOF,"SMP input file must be a file, not a pipe"); return(ST_EOF); } /* Read SampleVision header */ if (st_readbuf(ft, (char *)&header, 1, HEADERSIZE) != HEADERSIZE) { st_fail_errno(ft,ST_EHDR,"unexpected EOF in SMP header"); return(ST_EOF); } if (strncmp(header.Id, SVmagic, 17) != 0) { st_fail_errno(ft,ST_EHDR,"SMP header does not begin with magic word %s\n", SVmagic); return(ST_EOF); } if (strncmp(header.version, SVvers, 4) != 0) { st_fail_errno(ft,ST_EHDR,"SMP header is not version %s\n", SVvers); return(ST_EOF); } /* Format the sample name and comments to a single comment */ /* string. We decrement the counters till we encounter non */ /* padding space chars, so the *lengths* are low by one */ for (namelen = NAMELEN-1; namelen >= 0 && header.name[namelen] == ' '; namelen--) ; for (commentlen = COMMENTLEN-1; commentlen >= 0 && header.comments[commentlen] == ' '; commentlen--) ; sprintf(smp->comment, "%.*s: %.*s", namelen+1, header.name, commentlen+1, header.comments); ft->comment = smp->comment; st_report("SampleVision file name and comments: %s", ft->comment); /* Extract out the sample size (always intel format) */ st_readdw(ft, &(smp->NoOfSamps)); /* mark the start of the sample data */ samplestart = st_tell(ft); /* seek from the current position (the start of sample data) by */ /* NoOfSamps * sizeof(int16_t) */ if (st_seeki(ft, smp->NoOfSamps * 2L, 1) == -1) { st_fail_errno(ft,errno,"SMP unable to seek to trailer"); return(ST_EOF); } if (readtrailer(ft, &trailer)) { st_fail_errno(ft,ST_EHDR,"unexpected EOF in SMP trailer"); return(ST_EOF); } /* seek back to the beginning of the data */ if (st_seeki(ft, samplestart, 0) == -1) { st_fail_errno(ft,errno,"SMP unable to seek back to start of sample data"); return(ST_EOF); } ft->info.rate = (int) trailer.rate; ft->info.size = ST_SIZE_WORD; ft->info.encoding = ST_ENCODING_SIGN2; ft->info.channels = 1; smp->dataStart = samplestart; ft->length = smp->NoOfSamps; st_report("SampleVision trailer:\n"); for(i = 0; i < 8; i++) if (1 || trailer.loops[i].count) { #ifdef __alpha__ st_report("Loop %d: start: %6d", i, trailer.loops[i].start); st_report(" end: %6d", trailer.loops[i].end); #else st_report("Loop %d: start: %6ld", i, trailer.loops[i].start); st_report(" end: %6ld", trailer.loops[i].end); #endif st_report(" count: %6d", trailer.loops[i].count); switch(trailer.loops[i].type) { case 0: st_report("type: off\n"); break; case 1: st_report("type: forward\n"); break; case 2: st_report("type: forward/backward\n"); break; } } st_report("MIDI Note number: %d\n\n", trailer.MIDInote); ft->instr.nloops = 0; for(i = 0; i < 8; i++) if (trailer.loops[i].type) ft->instr.nloops++; for(i = 0; i < ft->instr.nloops; i++) { ft->loops[i].type = trailer.loops[i].type; ft->loops[i].count = trailer.loops[i].count; ft->loops[i].start = trailer.loops[i].start; ft->loops[i].length = trailer.loops[i].end - trailer.loops[i].start; } ft->instr.MIDIlow = ft->instr.MIDIhi = ft->instr.MIDInote = trailer.MIDInote; if (ft->instr.nloops > 0) ft->instr.loopmode = ST_LOOP_8; else ft->instr.loopmode = ST_LOOP_NONE; return(ST_SUCCESS); } /* * Read up to len samples from file. * Convert to signed longs. * Place in buf[]. * Return number of samples read. */ st_ssize_t st_smpread(ft_t ft, st_sample_t *buf, st_ssize_t len) { smp_t smp = (smp_t) ft->priv; unsigned short datum; int done = 0; for(; done < len && smp->NoOfSamps; done++, smp->NoOfSamps--) { st_readw(ft, &datum); /* scale signed up to long's range */ *buf++ = ST_SIGNED_WORD_TO_SAMPLE(datum); } return done; } /* * Do anything required when you stop reading samples. * Don't close input file! */ int st_smpstopread(ft_t ft) { return(ST_SUCCESS); } int st_smpstartwrite(ft_t ft) { smp_t smp = (smp_t) ft->priv; struct smpheader header; /* SMP is in Little Endian format. Swap whats read in on */ /* Big Endian machines. */ if (ST_IS_BIGENDIAN) { ft->swap = ft->swap ? 0 : 1; } /* If you have to seek around the output file */ if (! ft->seekable) { st_fail_errno(ft,ST_EOF,"Output .smp file must be a file, not a pipe"); return(ST_EOF); } /* If your format specifies any of the following info. */ ft->info.size = ST_SIZE_WORD; ft->info.encoding = ST_ENCODING_SIGN2; ft->info.channels = 1; strcpy(header.Id, SVmagic); strcpy(header.version, SVvers); sprintf(header.comments, "%-*s", COMMENTLEN, "Converted using Sox."); sprintf(header.name, "%-*.*s", NAMELEN, NAMELEN, ft->comment); /* Write file header */ if(st_writebuf(ft, &header, 1, HEADERSIZE) != HEADERSIZE) { st_fail_errno(ft,errno,"SMP: Can't write header completely"); return(ST_EOF); } st_writedw(ft, 0); /* write as zero length for now, update later */ smp->NoOfSamps = 0; return(ST_SUCCESS); } st_ssize_t st_smpwrite(ft_t ft, st_sample_t *buf, st_ssize_t len) { smp_t smp = (smp_t) ft->priv; register int datum; st_ssize_t done = 0; while(done < len) { datum = (int) ST_SAMPLE_TO_SIGNED_WORD(*buf++); st_writew(ft, datum); smp->NoOfSamps++; done++; } return(done); } int st_smpstopwrite(ft_t ft) { smp_t smp = (smp_t) ft->priv; struct smptrailer trailer; /* Assign the trailer data */ settrailer(ft, &trailer, ft->info.rate); writetrailer(ft, &trailer); if (st_seeki(ft, 112, 0) == -1) { st_fail_errno(ft,errno,"SMP unable to seek back to save size"); return(ST_EOF); } st_writedw(ft, smp->NoOfSamps); return(ST_SUCCESS); } /* SampleVision sound */ static char *smpnames[] = { "smp", NULL, }; st_format_t st_smp_format = { smpnames, NULL, ST_FILE_STEREO | ST_FILE_LOOPS | ST_FILE_SEEK, st_smpstartread, st_smpread, st_smpstopread, st_smpstartwrite, st_smpwrite, st_smpstopwrite, st_smpseek };