ref: ec9b7b9d5afeee67ff0c39de79018037d426d3ba
dir: /src/sphere.c/
/* libSoX NIST Sphere file format handler.
*
* August 7, 2000
*
* Copyright (C) 2000 Chris Bagwell (cbagwell@sprynet.com)
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or (at
* your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
* General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "sox_i.h"
#include <string.h>
static int start_read(sox_format_t * ft)
{
unsigned long header_size_ul = 0, num_samples_ul = 0;
sox_encoding_t encoding = SOX_ENCODING_SIGN2;
size_t header_size, bytes_read;
size_t num_samples = 0;
unsigned bytes_per_sample = 0;
unsigned channels = 1;
unsigned rate = 16000;
char fldname[64], fldtype[16], fldsval[128];
char * buf;
/* Magic header */
if (lsx_reads(ft, fldname, (size_t)8) || strncmp(fldname, "NIST_1A", (size_t)7) != 0) {
lsx_fail_errno(ft, SOX_EHDR, "Sphere header does not begin with magic word 'NIST_1A'");
return (SOX_EOF);
}
if (lsx_reads(ft, fldsval, (size_t)8)) {
lsx_fail_errno(ft, SOX_EHDR, "Error reading Sphere header");
return (SOX_EOF);
}
/* Determine header size, and allocate a buffer large enough to hold it. */
sscanf(fldsval, "%lu", &header_size_ul);
buf = lsx_malloc(header_size = header_size_ul);
/* Skip what we have read so far */
header_size -= 16;
if (lsx_reads(ft, buf, header_size) == SOX_EOF) {
lsx_fail_errno(ft, SOX_EHDR, "Error reading Sphere header");
free(buf);
return (SOX_EOF);
}
header_size -= (strlen(buf) + 1);
while (strncmp(buf, "end_head", (size_t)8) != 0) {
if (strncmp(buf, "sample_n_bytes", (size_t)14) == 0)
sscanf(buf, "%63s %15s %u", fldname, fldtype, &bytes_per_sample);
else if (strncmp(buf, "channel_count", (size_t)13) == 0)
sscanf(buf, "%63s %15s %u", fldname, fldtype, &channels);
else if (strncmp(buf, "sample_count ", (size_t)13) == 0)
sscanf(buf, "%53s %15s %lu", fldname, fldtype, &num_samples_ul);
else if (strncmp(buf, "sample_rate ", (size_t)12) == 0)
sscanf(buf, "%53s %15s %u", fldname, fldtype, &rate);
else if (strncmp(buf, "sample_coding", (size_t)13) == 0) {
sscanf(buf, "%63s %15s %127s", fldname, fldtype, fldsval);
if (!strcasecmp(fldsval, "ulaw") || !strcasecmp(fldsval, "mu-law"))
encoding = SOX_ENCODING_ULAW;
else if (!strcasecmp(fldsval, "pcm"))
encoding = SOX_ENCODING_SIGN2;
else {
lsx_fail_errno(ft, SOX_EFMT, "sph: unsupported coding `%s'", fldsval);
free(buf);
return SOX_EOF;
}
}
else if (strncmp(buf, "sample_byte_format", (size_t)18) == 0) {
sscanf(buf, "%53s %15s %127s", fldname, fldtype, fldsval);
if (strcmp(fldsval, "01") == 0) /* Data is little endian. */
ft->encoding.reverse_bytes = MACHINE_IS_BIGENDIAN;
else if (strcmp(fldsval, "10") == 0) /* Data is big endian. */
ft->encoding.reverse_bytes = MACHINE_IS_LITTLEENDIAN;
else if (strcmp(fldsval, "1")) {
lsx_fail_errno(ft, SOX_EFMT, "sph: unsupported coding `%s'", fldsval);
free(buf);
return SOX_EOF;
}
}
if (lsx_reads(ft, buf, header_size) == SOX_EOF) {
lsx_fail_errno(ft, SOX_EHDR, "Error reading Sphere header");
free(buf);
return (SOX_EOF);
}
header_size -= (strlen(buf) + 1);
}
if (!bytes_per_sample)
bytes_per_sample = encoding == SOX_ENCODING_ULAW? 1 : 2;
while (header_size) {
bytes_read = lsx_readbuf(ft, buf, header_size);
if (bytes_read == 0) {
free(buf);
return (SOX_EOF);
}
header_size -= bytes_read;
}
free(buf);
if (ft->seekable) {
/* Check first four bytes of data to see if it's shorten compressed. */
char shorten_check[4];
if (lsx_readchars(ft, shorten_check, sizeof(shorten_check)))
return SOX_EOF;
lsx_seeki(ft, -(off_t)sizeof(shorten_check), SEEK_CUR);
if (!memcmp(shorten_check, "ajkg", sizeof(shorten_check))) {
lsx_fail_errno(ft, SOX_EFMT,
"File uses shorten compression, cannot handle this.");
return (SOX_EOF);
}
}
num_samples = num_samples_ul;
return lsx_check_read_params(ft, channels, (sox_rate_t)rate, encoding,
bytes_per_sample << 3, (off_t)(num_samples * channels));
}
static int write_header(sox_format_t * ft)
{
char buf[128];
long samples = (ft->olength ? ft->olength : ft->signal.length) / ft->signal.channels;
lsx_writes(ft, "NIST_1A\n");
lsx_writes(ft, " 1024\n");
if (samples) {
sprintf(buf, "sample_count -i %ld\n", samples);
lsx_writes(ft, buf);
}
sprintf(buf, "sample_n_bytes -i %d\n", ft->encoding.bits_per_sample >> 3);
lsx_writes(ft, buf);
sprintf(buf, "channel_count -i %d\n", ft->signal.channels);
lsx_writes(ft, buf);
if (ft->encoding.bits_per_sample == 8)
sprintf(buf, "sample_byte_format -s1 1\n");
else
sprintf(buf, "sample_byte_format -s2 %s\n",
ft->encoding.reverse_bytes != MACHINE_IS_BIGENDIAN ? "10" : "01");
lsx_writes(ft, buf);
sprintf(buf, "sample_rate -i %u\n", (unsigned) (ft->signal.rate + .5));
lsx_writes(ft, buf);
if (ft->encoding.encoding == SOX_ENCODING_ULAW)
lsx_writes(ft, "sample_coding -s4 ulaw\n");
else
lsx_writes(ft, "sample_coding -s3 pcm\n");
lsx_writes(ft, "end_head\n");
lsx_padbytes(ft, 1024 - (size_t)lsx_tell(ft));
return SOX_SUCCESS;
}
SOX_FORMAT_HANDLER(sphere)
{
static char const *const names[] = {"sph", "nist", NULL};
static unsigned const write_encodings[] = {
SOX_ENCODING_SIGN2, 8, 16, 24, 32, 0,
SOX_ENCODING_ULAW, 8, 0,
0
};
static sox_format_handler_t const handler = {SOX_LIB_VERSION_CODE,
"SPeech HEader Resources; defined by NIST", names, SOX_FILE_REWIND,
start_read, lsx_rawread, NULL,
write_header, lsx_rawwrite, NULL,
lsx_rawseek, write_encodings, NULL, 0
};
return &handler;
}