summaryrefslogtreecommitdiffstats
path: root/sbc/sbcinfo.c
diff options
context:
space:
mode:
Diffstat (limited to 'sbc/sbcinfo.c')
-rw-r--r--sbc/sbcinfo.c300
1 files changed, 300 insertions, 0 deletions
diff --git a/sbc/sbcinfo.c b/sbc/sbcinfo.c
new file mode 100644
index 00000000..e34f5618
--- /dev/null
+++ b/sbc/sbcinfo.c
@@ -0,0 +1,300 @@
+/*
+ *
+ * Bluetooth low-complexity, subband codec (SBC) library
+ *
+ * Copyright (C) 2004-2007 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 <stdint.h>
+#include <string.h>
+#include <libgen.h>
+
+struct sbc_frame_hdr {
+ uint8_t syncword:8; /* Sync word */
+ uint8_t subbands:1; /* Subbands */
+ uint8_t allocation_method:1; /* Allocation method */
+ uint8_t channel_mode:2; /* Channel mode */
+ uint8_t blocks:2; /* Blocks */
+ uint8_t sampling_frequency:2; /* Sampling frequency */
+ uint8_t bitpool:8; /* Bitpool */
+ uint8_t crc_check:8; /* CRC check */
+} __attribute__ ((packed));
+
+static int calc_frame_len(struct sbc_frame_hdr *hdr)
+{
+ int tmp, nrof_subbands, nrof_blocks;
+
+ nrof_subbands = (hdr->subbands + 1) * 4;
+ nrof_blocks = (hdr->blocks + 1) * 4;
+
+ switch (hdr->channel_mode) {
+ case 0x00:
+ nrof_subbands /= 2;
+ tmp = nrof_blocks * hdr->bitpool;
+ break;
+ case 0x01:
+ tmp = nrof_blocks * hdr->bitpool * 2;
+ break;
+ case 0x02:
+ tmp = nrof_blocks * hdr->bitpool;
+ break;
+ case 0x03:
+ tmp = nrof_blocks * hdr->bitpool + nrof_subbands;
+ break;
+ default:
+ return 0;
+ }
+
+ return (nrof_subbands + ((tmp + 7) / 8));
+}
+
+static double calc_bit_rate(struct sbc_frame_hdr *hdr)
+{
+ int nrof_subbands, nrof_blocks;
+ double f;
+
+ nrof_subbands = (hdr->subbands + 1) * 4;
+ nrof_blocks = (hdr->blocks + 1) * 4;
+
+ switch (hdr->sampling_frequency) {
+ case 0:
+ f = 16;
+ break;
+ case 1:
+ f = 32;
+ break;
+ case 2:
+ f = 44.1;
+ break;
+ case 3:
+ f = 48;
+ break;
+ default:
+ return 0;
+ }
+
+ return ((8 * (calc_frame_len(hdr) + 4) * f) / (nrof_subbands * nrof_blocks));
+}
+
+static char *freq2str(uint8_t freq)
+{
+ switch (freq) {
+ case 0:
+ return "16 kHz";
+ case 1:
+ return "32 kHz";
+ case 2:
+ return "44.1 kHz";
+ case 3:
+ return "48 kHz";
+ default:
+ return "Unknown";
+ }
+}
+
+static char *mode2str(uint8_t mode)
+{
+ switch (mode) {
+ case 0:
+ return "Mono";
+ case 1:
+ return "Dual Channel";
+ case 2:
+ return "Stereo";
+ case 3:
+ return "Joint Stereo";
+ default:
+ return "Unknown";
+ }
+}
+
+static ssize_t __read(int fd, void *buf, size_t count)
+{
+ ssize_t len, pos = 0;
+
+ while (count > 0) {
+ len = read(fd, buf + pos, count);
+ if (len <= 0)
+ return len;
+
+ count -= len;
+ pos += len;
+ }
+
+ return pos;
+}
+
+#define SIZE 32
+
+static int analyze_file(char *filename)
+{
+ struct sbc_frame_hdr hdr;
+ unsigned char buf[64];
+ double rate;
+ int bitpool[SIZE], frame_len[SIZE];
+ int subbands, blocks, freq, mode, method;
+ int n, p1, p2, fd, len, size, count, num;
+
+ if (strcmp(filename, "-")) {
+ printf("Filename\t\t%s\n", basename(filename));
+
+ fd = open(filename, O_RDONLY);
+ if (fd < 0) {
+ perror("Can't open file");
+ return -1;
+ }
+ } else
+ fd = fileno(stdin);
+
+ len = __read(fd, &hdr, sizeof(hdr));
+ if (len != sizeof(hdr) || hdr.syncword != 0x9c) {
+ fprintf(stderr, "Not a SBC audio file\n");
+ return -1;
+ }
+
+ subbands = (hdr.subbands + 1) * 4;
+ blocks = (hdr.blocks + 1) * 4;
+ freq = hdr.sampling_frequency;
+ mode = hdr.channel_mode;
+ method = hdr.allocation_method;
+
+ count = calc_frame_len(&hdr);
+
+ bitpool[0] = hdr.bitpool;
+ frame_len[0] = count + 4;
+
+ for (n = 1; n < SIZE; n++) {
+ bitpool[n] = 0;
+ frame_len[n] = 0;
+ }
+
+ if (lseek(fd, 0, SEEK_SET) < 0) {
+ num = 1;
+ rate = calc_bit_rate(&hdr);
+ while (count) {
+ size = count > sizeof(buf) ? sizeof(buf) : count;
+ len = __read(fd, buf, size);
+ if (len < 0)
+ break;
+ count -= len;
+ }
+ } else {
+ num = 0;
+ rate = 0;
+ }
+
+ while (1) {
+ len = __read(fd, &hdr, sizeof(hdr));
+ if (len < 0) {
+ fprintf(stderr, "Unable to read frame header (error %d)\n", errno);
+ break;
+ }
+
+ if (len == 0)
+ break;
+
+ if (len < sizeof(hdr) || hdr.syncword != 0x9c) {
+ fprintf(stderr, "Corrupted SBC stream (len %d syncword 0x%02x)\n",
+ len, hdr.syncword);
+ break;
+ }
+
+ count = calc_frame_len(&hdr);
+ len = count + 4;
+
+ p1 = -1;
+ p2 = -1;
+ for (n = 0; n < SIZE; n++) {
+ if (p1 < 0 && (bitpool[n] == 0 || bitpool[n] == hdr.bitpool))
+ p1 = n;
+ if (p2 < 0 && (frame_len[n] == 0 || frame_len[n] == len))
+ p2 = n;
+ }
+ if (p1 >= 0)
+ bitpool[p1] = hdr.bitpool;
+ if (p2 >= 0)
+ frame_len[p2] = len;
+
+ while (count) {
+ size = count > sizeof(buf) ? sizeof(buf) : count;
+
+ len = __read(fd, buf, size);
+ if (len != size) {
+ fprintf(stderr, "Unable to read frame data (error %d)\n", errno);
+ break;
+ }
+
+ count -= len;
+ }
+
+ rate += calc_bit_rate(&hdr);
+ num++;
+ }
+
+ printf("Subbands\t\t%d\n", subbands);
+ printf("Block length\t\t%d\n", blocks);
+ printf("Sampling frequency\t%s\n", freq2str(freq));
+ printf("Channel mode\t\t%s\n", mode2str(hdr.channel_mode));
+ printf("Allocation method\t%s\n", method ? "SNR" : "Loudness");
+ printf("Bitpool\t\t\t%d", bitpool[0]);
+ for (n = 1; n < SIZE; n++)
+ if (bitpool[n] > 0)
+ printf(", %d", bitpool[n]);
+ printf("\n");
+ printf("Number of frames\t%d\n", num);
+ printf("Frame length\t\t%d", frame_len[0]);
+ for (n = 1; n < SIZE; n++)
+ if (frame_len[n] > 0)
+ printf(", %d", frame_len[n]);
+ printf(" Bytes\n");
+ if (num > 0)
+ printf("Bit rate\t\t%.3f kbps\n", rate / num);
+
+ if (fd > fileno(stderr))
+ close(fd);
+
+ printf("\n");
+
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ int i;
+
+ if (argc < 2) {
+ fprintf(stderr, "Usage: sbcinfo <file>\n");
+ exit(1);
+ }
+
+ for (i = 0; i < argc - 1; i++)
+ if (analyze_file(argv[i + 1]) < 0)
+ exit(1);
+
+ return 0;
+}
generated by cgit (git 2.34.1) at 2025-10-30 02:47:39 +0000