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authormarkster <markster@f38db490-d61c-443f-a65b-d21fe96a405b>2001-03-22 22:25:06 +0000
committermarkster <markster@f38db490-d61c-443f-a65b-d21fe96a405b>2001-03-22 22:25:06 +0000
commitf7f902ae13273469d523bb80c3f1e107ca0f1789 (patch)
treec967274e7368f940e08151d1815e6cf9d10a37ab /formats/format_vox.c
parentec2340452e7bf4f3a20cf964758b3e035606adbb (diff)
Version 0.1.7 from FTP
git-svn-id: http://svn.digium.com/svn/asterisk/trunk@254 f38db490-d61c-443f-a65b-d21fe96a405b
Diffstat (limited to 'formats/format_vox.c')
-rwxr-xr-xformats/format_vox.c422
1 files changed, 422 insertions, 0 deletions
diff --git a/formats/format_vox.c b/formats/format_vox.c
new file mode 100755
index 000000000..3143f6ccb
--- /dev/null
+++ b/formats/format_vox.c
@@ -0,0 +1,422 @@
+/*
+ * Asterisk -- A telephony toolkit for Linux.
+ *
+ * Flat, binary, ADPCM vox file format.
+ *
+ * Copyright (C) 1999, Mark Spencer
+ *
+ * Mark Spencer <markster@linux-support.net>
+ *
+ * This program is free software, distributed under the terms of
+ * the GNU General Public License
+ */
+
+#include <asterisk/channel.h>
+#include <asterisk/file.h>
+#include <asterisk/logger.h>
+#include <asterisk/sched.h>
+#include <asterisk/module.h>
+#include <arpa/inet.h>
+#include <stdlib.h>
+#include <sys/time.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <pthread.h>
+#include <endian.h>
+
+#define BUF_SIZE 80 /* 160 samples */
+
+struct ast_filestream {
+ void *reserved[AST_RESERVED_POINTERS];
+ /* Believe it or not, we must decode/recode to account for the
+ weird MS format */
+ /* This is what a filestream means to us */
+ int fd; /* Descriptor */
+ struct ast_channel *owner;
+ struct ast_frame fr; /* Frame information */
+ char waste[AST_FRIENDLY_OFFSET]; /* Buffer for sending frames, etc */
+ char empty; /* Empty character */
+ unsigned char buf[BUF_SIZE + 3]; /* Output Buffer */
+ int lasttimeout;
+ struct timeval last;
+ int adj;
+ short signal; /* Signal level (file side) */
+ short ssindex; /* Signal ssindex (file side) */
+ struct ast_filestream *next;
+};
+
+
+static struct ast_filestream *glist = NULL;
+static pthread_mutex_t vox_lock = PTHREAD_MUTEX_INITIALIZER;
+static int glistcnt = 0;
+
+static char *name = "vox";
+static char *desc = "Dialogic VOX (ADPCM) File Format";
+static char *exts = "vox";
+
+/*
+ * Step size index shift table
+ */
+
+static short indsft[8] = { -1, -1, -1, -1, 2, 4, 6, 8 };
+
+/*
+ * Step size table, where stpsz[i]=floor[16*(11/10)^i]
+ */
+
+static short stpsz[49] = {
+ 16, 17, 19, 21, 23, 25, 28, 31, 34, 37, 41, 45, 50, 55, 60, 66, 73,
+ 80, 88, 97, 107, 118, 130, 143, 157, 173, 190, 209, 230, 253, 279,
+ 307, 337, 371, 408, 449, 494, 544, 598, 658, 724, 796, 876, 963,
+ 1060, 1166, 1282, 1411, 1552
+};
+
+/*
+ * Nibble to bit map
+ */
+
+static short nbl2bit[16][4] = {
+ {1, 0, 0, 0}, {1, 0, 0, 1}, {1, 0, 1, 0}, {1, 0, 1, 1},
+ {1, 1, 0, 0}, {1, 1, 0, 1}, {1, 1, 1, 0}, {1, 1, 1, 1},
+ {-1, 0, 0, 0}, {-1, 0, 0, 1}, {-1, 0, 1, 0}, {-1, 0, 1, 1},
+ {-1, 1, 0, 0}, {-1, 1, 0, 1}, {-1, 1, 1, 0}, {-1, 1, 1, 1}
+};
+
+/*
+ * Decode(encoded)
+ * Decodes the encoded nibble from the adpcm file.
+ *
+ * Results:
+ * Returns the encoded difference.
+ *
+ * Side effects:
+ * Sets the index to the step size table for the next encode.
+ */
+
+static inline short
+decode (unsigned char encoded, short *ssindex)
+{
+ short diff, step;
+ step = stpsz[*ssindex];
+ diff = nbl2bit[encoded][0] * (step * nbl2bit[encoded][1] +
+ (step >> 1) * nbl2bit[encoded][2] +
+ (step >> 2) * nbl2bit[encoded][3] +
+ (step >> 3));
+ *ssindex = *ssindex + indsft[(encoded & 7)];
+ if (*ssindex < 0)
+ *ssindex = 0;
+ else if (*ssindex > 48)
+ *ssindex = 48;
+ return (diff);
+}
+
+/*
+ * Adpcm
+ * Takes a signed linear signal and encodes it as ADPCM
+ * For more information see http://support.dialogic.com/appnotes/adpcm.pdf
+ *
+ * Results:
+ * Foo.
+ *
+ * Side effects:
+ * signal gets updated with each pass.
+ */
+
+static inline unsigned char
+adpcm (short csig, short *ssindex, short *signal)
+{
+ short diff, step;
+ unsigned char encoded;
+ step = stpsz[*ssindex];
+ /*
+ * Clip csig if too large or too small
+ */
+
+ csig >>= 4;
+
+ diff = csig - *signal;
+
+ if (diff < 0)
+ {
+ encoded = 8;
+ diff = -diff;
+ }
+ else
+ encoded = 0;
+ if (diff >= step)
+ {
+ encoded |= 4;
+ diff -= step;
+ }
+ step >>= 1;
+ if (diff >= step)
+ {
+ encoded |= 2;
+ diff -= step;
+ }
+ step >>= 1;
+ if (diff >= step)
+ encoded |= 1;
+
+ *signal += decode (encoded, ssindex);
+ return (encoded);
+}
+
+static struct ast_filestream *vox_open(int fd)
+{
+ /* We don't have any header to read or anything really, but
+ if we did, it would go here. We also might want to check
+ and be sure it's a valid file. */
+ struct ast_filestream *tmp;
+ if ((tmp = malloc(sizeof(struct ast_filestream)))) {
+ memset(tmp, 0, sizeof(struct ast_filestream));
+ if (pthread_mutex_lock(&vox_lock)) {
+ ast_log(LOG_WARNING, "Unable to lock vox list\n");
+ free(tmp);
+ return NULL;
+ }
+ tmp->next = glist;
+ glist = tmp;
+ tmp->fd = fd;
+ tmp->owner = NULL;
+ tmp->fr.data = tmp->buf;
+ tmp->fr.frametype = AST_FRAME_VOICE;
+ tmp->fr.subclass = AST_FORMAT_ADPCM;
+ /* datalen will vary for each frame */
+ tmp->fr.src = name;
+ tmp->fr.mallocd = 0;
+ tmp->lasttimeout = -1;
+ glistcnt++;
+ pthread_mutex_unlock(&vox_lock);
+ ast_update_use_count();
+ }
+ return tmp;
+}
+
+static struct ast_filestream *vox_rewrite(int fd, char *comment)
+{
+ /* We don't have any header to read or anything really, but
+ if we did, it would go here. We also might want to check
+ and be sure it's a valid file. */
+ struct ast_filestream *tmp;
+ if ((tmp = malloc(sizeof(struct ast_filestream)))) {
+ memset(tmp, 0, sizeof(struct ast_filestream));
+ if (pthread_mutex_lock(&vox_lock)) {
+ ast_log(LOG_WARNING, "Unable to lock vox list\n");
+ free(tmp);
+ return NULL;
+ }
+ tmp->next = glist;
+ glist = tmp;
+ tmp->fd = fd;
+ tmp->owner = NULL;
+ tmp->lasttimeout = -1;
+ glistcnt++;
+ pthread_mutex_unlock(&vox_lock);
+ ast_update_use_count();
+ } else
+ ast_log(LOG_WARNING, "Out of memory\n");
+ return tmp;
+}
+
+static struct ast_frame *vox_read(struct ast_filestream *s)
+{
+ return NULL;
+}
+
+static void vox_close(struct ast_filestream *s)
+{
+ struct ast_filestream *tmp, *tmpl = NULL;
+ if (pthread_mutex_lock(&vox_lock)) {
+ ast_log(LOG_WARNING, "Unable to lock vox list\n");
+ return;
+ }
+ tmp = glist;
+ while(tmp) {
+ if (tmp == s) {
+ if (tmpl)
+ tmpl->next = tmp->next;
+ else
+ glist = tmp->next;
+ break;
+ }
+ tmpl = tmp;
+ tmp = tmp->next;
+ }
+ glistcnt--;
+ if (s->owner) {
+ s->owner->stream = NULL;
+ if (s->owner->streamid > -1)
+ ast_sched_del(s->owner->sched, s->owner->streamid);
+ s->owner->streamid = -1;
+ }
+ pthread_mutex_unlock(&vox_lock);
+ ast_update_use_count();
+ if (!tmp)
+ ast_log(LOG_WARNING, "Freeing a filestream we don't seem to own\n");
+ close(s->fd);
+ free(s);
+}
+
+static int ast_read_callback(void *data)
+{
+ int retval = 0;
+ int res;
+ int delay;
+ struct ast_filestream *s = data;
+ struct timeval tv;
+ int x;
+ /* Send a frame from the file to the appropriate channel */
+
+ s->fr.frametype = AST_FRAME_VOICE;
+ s->fr.subclass = AST_FORMAT_ADPCM;
+ s->fr.offset = AST_FRIENDLY_OFFSET;
+ s->fr.mallocd = 0;
+ s->fr.data = s->buf;
+ if ((res = read(s->fd, s->buf + 3, BUF_SIZE)) < 1) {
+ if (res)
+ ast_log(LOG_WARNING, "Short read (%d) (%s)!\n", res, strerror(errno));
+ s->owner->streamid = -1;
+ return 0;
+ }
+ /* Store index, then signal */
+ s->buf[0] = s->ssindex & 0xff;
+ s->buf[1] = (s->signal >> 8) & 0xff;
+ s->buf[2] = s->signal & 0xff;
+ /* Do the decoder to be sure we get the right stuff in the signal and index fields. */
+ for (x=3;x<res+3;x++) {
+ s->signal += decode(s->buf[x] >> 4, &s->ssindex);
+ s->signal += decode(s->buf[x] & 0xf, &s->ssindex);
+ }
+ s->fr.timelen = res / 4;
+ s->fr.datalen = res + 3;
+ delay = s->fr.timelen;
+ /* Lastly, process the frame */
+ if (ast_write(s->owner, &s->fr)) {
+ ast_log(LOG_WARNING, "Failed to write frame\n");
+ s->owner->streamid = -1;
+ return 0;
+ }
+ if (s->last.tv_usec || s->last.tv_usec) {
+ int ms;
+ gettimeofday(&tv, NULL);
+ ms = 1000 * (tv.tv_sec - s->last.tv_sec) +
+ (tv.tv_usec - s->last.tv_usec) / 1000;
+ s->last.tv_sec = tv.tv_sec;
+ s->last.tv_usec = tv.tv_usec;
+ if ((ms - delay) * (ms - delay) > 4) {
+ /* Compensate if we're more than 2 ms off */
+ s->adj -= (ms - delay);
+ }
+#if 0
+ fprintf(stdout, "Delay is %d, adjustment is %d, last was %d\n", delay, s->adj, ms);
+#endif
+ delay += s->adj;
+ if (delay < 1)
+ delay = 1;
+ } else
+ gettimeofday(&s->last, NULL);
+ if (s->lasttimeout != delay) {
+ /* We'll install the next timeout now. */
+ s->owner->streamid = ast_sched_add(s->owner->sched,
+ delay, ast_read_callback, s);
+ s->lasttimeout = delay;
+ } else {
+ /* Just come back again at the same time */
+ retval = -1;
+ }
+ return retval;
+}
+
+static int vox_apply(struct ast_channel *c, struct ast_filestream *s)
+{
+ /* Select our owner for this stream, and get the ball rolling. */
+ s->owner = c;
+ ast_read_callback(s);
+ return 0;
+}
+
+static int vox_write(struct ast_filestream *fs, struct ast_frame *f)
+{
+ int res;
+ if (f->frametype != AST_FRAME_VOICE) {
+ ast_log(LOG_WARNING, "Asked to write non-voice frame!\n");
+ return -1;
+ }
+ if (f->subclass != AST_FORMAT_ADPCM) {
+ ast_log(LOG_WARNING, "Asked to write non-ADPCM frame (%d)!\n", f->subclass);
+ return -1;
+ }
+ if (f->datalen < 3) {
+ ast_log(LOG_WARNING, "Invalid frame of data (< 3 bytes long) from %s\n", f->src);
+ return -1;
+ }
+ if ((res = write(fs->fd, f->data + 3, f->datalen)) != f->datalen) {
+ ast_log(LOG_WARNING, "Bad write (%d/%d): %s\n", res, f->datalen, strerror(errno));
+ return -1;
+ }
+ return 0;
+}
+
+static char *vox_getcomment(struct ast_filestream *s)
+{
+ return NULL;
+}
+
+int load_module()
+{
+ return ast_format_register(name, exts, AST_FORMAT_ADPCM,
+ vox_open,
+ vox_rewrite,
+ vox_apply,
+ vox_write,
+ vox_read,
+ vox_close,
+ vox_getcomment);
+
+
+}
+
+int unload_module()
+{
+ struct ast_filestream *tmp, *tmpl;
+ if (pthread_mutex_lock(&vox_lock)) {
+ ast_log(LOG_WARNING, "Unable to lock vox list\n");
+ return -1;
+ }
+ tmp = glist;
+ while(tmp) {
+ if (tmp->owner)
+ ast_softhangup(tmp->owner);
+ tmpl = tmp;
+ tmp = tmp->next;
+ free(tmpl);
+ }
+ pthread_mutex_unlock(&vox_lock);
+ return ast_format_unregister(name);
+}
+
+int usecount()
+{
+ int res;
+ if (pthread_mutex_lock(&vox_lock)) {
+ ast_log(LOG_WARNING, "Unable to lock vox list\n");
+ return -1;
+ }
+ res = glistcnt;
+ pthread_mutex_unlock(&vox_lock);
+ return res;
+}
+
+char *description()
+{
+ return desc;
+}
+
+
+char *key()
+{
+ return ASTERISK_GPL_KEY;
+}