diff options
Diffstat (limited to 'sbc/sbcdec.c')
-rw-r--r-- | sbc/sbcdec.c | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/sbc/sbcdec.c b/sbc/sbcdec.c new file mode 100644 index 00000000..5ac02b44 --- /dev/null +++ b/sbc/sbcdec.c @@ -0,0 +1,267 @@ +/* + * + * Bluetooth low-complexity, subband codec (SBC) decoder + * + * Copyright (C) 2004-2008 Marcel Holtmann <marcel@holtmann.org> + * + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <stdio.h> +#include <errno.h> +#include <fcntl.h> +#include <unistd.h> +#include <stdlib.h> +#include <string.h> +#include <getopt.h> +#include <sys/stat.h> +#include <sys/ioctl.h> +#include <sys/soundcard.h> + +#include "sbc.h" + +#define BUF_SIZE 8192 + +static void decode(char *filename, char *output, int tofile) +{ + unsigned char buf[BUF_SIZE], *stream; + struct stat st; + off_t filesize; + sbc_t sbc; + int fd, ad, pos, streamlen, framelen, count, written, len; + int format = AFMT_S16_BE, frequency, channels; + + if (stat(filename, &st) < 0) { + fprintf(stderr, "Can't get size of file %s: %s\n", + filename, strerror(errno)); + return; + } + + filesize = st.st_size; + stream = malloc(st.st_size); + + if (!stream) { + fprintf(stderr, "Can't allocate memory for %s: %s\n", + filename, strerror(errno)); + return; + } + + fd = open(filename, O_RDONLY); + if (fd < 0) { + fprintf(stderr, "Can't open file %s: %s\n", + filename, strerror(errno)); + goto free; + } + + if (read(fd, stream, st.st_size) != st.st_size) { + fprintf(stderr, "Can't read content of %s: %s\n", + filename, strerror(errno)); + close(fd); + goto free; + } + + close(fd); + + pos = 0; + streamlen = st.st_size; + + if (tofile) + ad = open(output, O_WRONLY | O_CREAT | O_TRUNC, 0644); + else + ad = open(output, O_WRONLY, 0); + + if (ad < 0) { + fprintf(stderr, "Can't open output %s: %s\n", + output, strerror(errno)); + goto free; + } + + sbc_init(&sbc, 0L); + sbc.endian = SBC_BE; + + framelen = sbc_decode(&sbc, stream, streamlen, buf, sizeof(buf), &len); + channels = sbc.mode == SBC_MODE_MONO ? 1 : 2; + switch (sbc.frequency) { + case SBC_FREQ_16000: + frequency = 16000; + break; + + case SBC_FREQ_32000: + frequency = 32000; + break; + + case SBC_FREQ_44100: + frequency = 44100; + break; + + case SBC_FREQ_48000: + frequency = 48000; + break; + default: + frequency = 0; + } + + printf("%d Hz, %d channels\n", frequency, channels); + if (!tofile) { + if (ioctl(ad, SNDCTL_DSP_SETFMT, &format) < 0) { + fprintf(stderr, "Can't set audio format on %s: %s\n", + output, strerror(errno)); + goto close; + } + if (ioctl(ad, SNDCTL_DSP_CHANNELS, &channels) < 0) { + fprintf(stderr, + "Can't set number of channels on %s: %s\n", + output, strerror(errno)); + goto close; + } + + if (ioctl(ad, SNDCTL_DSP_SPEED, &frequency) < 0) { + fprintf(stderr, "Can't set audio rate on %s: %s\n", + output, strerror(errno)); + goto close; + } + } + + count = 0; + while (framelen > 0) { + /* we have completed an sbc_decode at this point sbc.len is the + * length of the frame we just decoded count is the number of + * decoded bytes yet to be written */ + + if (count + len >= BUF_SIZE) { + /* buffer is too full to stuff decoded audio in so it + * must be written to the device */ + written = write(ad, buf, count); + if (written > 0) + count -= written; + } + + /* sanity check */ + if (count + len >= BUF_SIZE) { + fprintf(stderr, + "buffer size of %d is too small for decoded" + " data (%d)\n", BUF_SIZE, len + count); + exit(1); + } + + /* increase the count */ + count += len; + + /* push the pointer in the file forward to the next bit to be + * decoded tell the decoder to decode up to the remaining + * length of the file (!) */ + pos += framelen; + framelen = sbc_decode(&sbc, stream + pos, streamlen - pos, + buf + count, sizeof(buf) - count, + &len); + } + + if (count > 0) { + written = write(ad, buf, count); + if (written > 0) + count -= written; + } + +close: + sbc_finish(&sbc); + + close(ad); + +free: + free(stream); +} + +static void usage(void) +{ + printf("SBC decoder utility ver %s\n", VERSION); + printf("Copyright (c) 2004-2008 Marcel Holtmann\n\n"); + + printf("Usage:\n" + "\tsbcdec [options] file(s)\n" + "\n"); + + printf("Options:\n" + "\t-h, --help Display help\n" + "\t-v, --verbose Verbose mode\n" + "\t-d, --device <dsp> Sound device\n" + "\t-f, --file <file> Decode to a file\n" + "\n"); +} + +static struct option main_options[] = { + { "help", 0, 0, 'h' }, + { "device", 1, 0, 'd' }, + { "verbose", 0, 0, 'v' }, + { "file", 1, 0, 'f' }, + { 0, 0, 0, 0 } +}; + +int main(int argc, char *argv[]) +{ + char *output = NULL; + int i, opt, verbose = 0, tofile = 0; + + while ((opt = getopt_long(argc, argv, "+hvd:f:", main_options, NULL)) != -1) { + switch(opt) { + case 'h': + usage(); + exit(0); + + case 'v': + verbose = 1; + break; + + case 'd': + if (output) + free(output); + output = strdup(optarg); + tofile = 0; + break; + + case 'f' : + if (output) + free(output); + output = strdup(optarg); + tofile = 1; + break; + + default: + exit(1); + } + } + + argc -= optind; + argv += optind; + optind = 0; + + if (argc < 1) { + usage(); + exit(1); + } + + for (i = 0; i < argc; i++) + decode(argv[i], output ? output : "/dev/dsp", tofile); + + if (output) + free(output); + + return 0; +} |