mirror of https://github.com/asterisk/asterisk
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@254 65c4cc65-6c06-0410-ace0-fbb531ad65f31.0
Mark Spencer
24 years ago
parent
a28c19e326
commit
cc1ca5d154
@ -0,0 +1,545 @@
|
||||
/* codec_adpcm.c - translate between signed linear and Dialogic ADPCM
|
||||
*
|
||||
* Asterisk -- A telephony toolkit for Linux.
|
||||
*
|
||||
* Based on frompcm.c and topcm.c from the Emiliano MIPL browser/
|
||||
* interpreter. See http://www.bsdtelephony.com.mx
|
||||
*
|
||||
* Copyright (c) 2001 Linux Support Services, Inc. All rights reserved.
|
||||
*
|
||||
* Karl Sackett <krs@linux-support.net>, 2001-3-21
|
||||
*
|
||||
* This program is free software, distributed under the terms of
|
||||
* the GNU General Public License
|
||||
*/
|
||||
|
||||
#include <asterisk/logger.h>
|
||||
#include <asterisk/module.h>
|
||||
#include <asterisk/translate.h>
|
||||
#include <fcntl.h>
|
||||
#include <netinet/in.h>
|
||||
#include <pthread.h>
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
#include <string.h>
|
||||
#include <unistd.h>
|
||||
|
||||
#define BUFFER_SIZE 8096 /* size for the translation buffers */
|
||||
|
||||
static pthread_mutex_t localuser_lock = PTHREAD_MUTEX_INITIALIZER;
|
||||
static int localusecnt = 0;
|
||||
|
||||
static char *tdesc = "Adaptive Differential PCM Coder/Decoder";
|
||||
|
||||
/* Sample frame data */
|
||||
|
||||
#include "slin_adpcm_ex.h"
|
||||
#include "adpcm_slin_ex.h"
|
||||
|
||||
/*
|
||||
* 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);
|
||||
}
|
||||
|
||||
/*
|
||||
* Private workspace for translating signed linear signals to ADPCM.
|
||||
*/
|
||||
|
||||
struct adpcm_encoder_pvt
|
||||
{
|
||||
struct ast_frame f;
|
||||
char offset[AST_FRIENDLY_OFFSET]; /* Space to build offset */
|
||||
short inbuf[BUFFER_SIZE]; /* Unencoded signed linear values */
|
||||
unsigned char outbuf[BUFFER_SIZE]; /* Encoded ADPCM, two nibbles to a word */
|
||||
short ssindex;
|
||||
short signal;
|
||||
int tail;
|
||||
};
|
||||
|
||||
/*
|
||||
* Private workspace for translating ADPCM signals to signed linear.
|
||||
*/
|
||||
|
||||
struct adpcm_decoder_pvt
|
||||
{
|
||||
struct ast_frame f;
|
||||
char offset[AST_FRIENDLY_OFFSET]; /* Space to build offset */
|
||||
short outbuf[BUFFER_SIZE]; /* Decoded signed linear values */
|
||||
int tail;
|
||||
};
|
||||
|
||||
/*
|
||||
* AdpcmToLin_New
|
||||
* Create a new instance of adpcm_decoder_pvt.
|
||||
*
|
||||
* Results:
|
||||
* Returns a pointer to the new instance.
|
||||
*
|
||||
* Side effects:
|
||||
* None.
|
||||
*/
|
||||
|
||||
static struct ast_translator_pvt *
|
||||
adpcmtolin_new ()
|
||||
{
|
||||
struct adpcm_decoder_pvt *tmp;
|
||||
tmp = malloc (sizeof (struct adpcm_decoder_pvt));
|
||||
if (tmp)
|
||||
{
|
||||
memset(tmp, 0, sizeof(*tmp));
|
||||
tmp->tail = 0;
|
||||
localusecnt++;
|
||||
ast_update_use_count ();
|
||||
}
|
||||
return (struct ast_translator_pvt *) tmp;
|
||||
}
|
||||
|
||||
/*
|
||||
* LinToAdpcm_New
|
||||
* Create a new instance of adpcm_encoder_pvt.
|
||||
*
|
||||
* Results:
|
||||
* Returns a pointer to the new instance.
|
||||
*
|
||||
* Side effects:
|
||||
* None.
|
||||
*/
|
||||
|
||||
static struct ast_translator_pvt *
|
||||
lintoadpcm_new ()
|
||||
{
|
||||
struct adpcm_encoder_pvt *tmp;
|
||||
tmp = malloc (sizeof (struct adpcm_encoder_pvt));
|
||||
if (tmp)
|
||||
{
|
||||
memset(tmp, 0, sizeof(*tmp));
|
||||
localusecnt++;
|
||||
ast_update_use_count ();
|
||||
tmp->tail = 0;
|
||||
}
|
||||
return (struct ast_translator_pvt *) tmp;
|
||||
}
|
||||
|
||||
/*
|
||||
* AdpcmToLin_FrameIn
|
||||
* Fill an input buffer with packed 4-bit ADPCM values if there is room
|
||||
* left.
|
||||
*
|
||||
* Results:
|
||||
* Foo
|
||||
*
|
||||
* Side effects:
|
||||
* tmp->tail is the number of packed values in the buffer.
|
||||
*/
|
||||
|
||||
static int
|
||||
adpcmtolin_framein (struct ast_translator_pvt *pvt, struct ast_frame *f)
|
||||
{
|
||||
struct adpcm_decoder_pvt *tmp = (struct adpcm_decoder_pvt *) pvt;
|
||||
int x;
|
||||
short signal;
|
||||
short ssindex;
|
||||
unsigned char *b;
|
||||
|
||||
if (f->datalen < 3) {
|
||||
ast_log(LOG_WARNING, "Didn't have at least three bytes of input\n");
|
||||
return -1;
|
||||
}
|
||||
|
||||
if ((f->datalen - 3) * 4 > sizeof(tmp->outbuf)) {
|
||||
ast_log(LOG_WARNING, "Out of buffer space\n");
|
||||
return -1;
|
||||
}
|
||||
|
||||
/* Reset ssindex and signal to frame's specified values */
|
||||
b = f->data;
|
||||
ssindex = b[0];
|
||||
if (ssindex < 0)
|
||||
ssindex = 0;
|
||||
if (ssindex > 48)
|
||||
ssindex = 48;
|
||||
|
||||
signal = (b[1] << 8) | b[2];
|
||||
|
||||
for (x=3;x<f->datalen;x++) {
|
||||
signal += decode(b[x] >> 4, &ssindex);
|
||||
if (signal > 2047)
|
||||
signal = 2047;
|
||||
if (signal < -2048)
|
||||
signal = -2048;
|
||||
tmp->outbuf[tmp->tail++] = signal << 4;
|
||||
signal += decode(b[x] & 0x0f, &ssindex);
|
||||
if (signal > 2047)
|
||||
signal = 2047;
|
||||
if (signal < -2048)
|
||||
signal = -2048;
|
||||
tmp->outbuf[tmp->tail++] = signal << 4;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* AdpcmToLin_FrameOut
|
||||
* Convert 4-bit ADPCM encoded signals to 16-bit signed linear.
|
||||
*
|
||||
* Results:
|
||||
* Converted signals are placed in tmp->f.data, tmp->f.datalen
|
||||
* and tmp->f.timelen are calculated.
|
||||
*
|
||||
* Side effects:
|
||||
* None.
|
||||
*/
|
||||
|
||||
static struct ast_frame *
|
||||
adpcmtolin_frameout (struct ast_translator_pvt *pvt)
|
||||
{
|
||||
struct adpcm_decoder_pvt *tmp = (struct adpcm_decoder_pvt *) pvt;
|
||||
|
||||
if (!tmp->tail)
|
||||
return NULL;
|
||||
|
||||
tmp->f.frametype = AST_FRAME_VOICE;
|
||||
tmp->f.subclass = AST_FORMAT_SLINEAR;
|
||||
tmp->f.datalen = tmp->tail *2;
|
||||
tmp->f.timelen = tmp->tail / 8;
|
||||
tmp->f.mallocd = 0;
|
||||
tmp->f.offset = AST_FRIENDLY_OFFSET;
|
||||
tmp->f.src = __PRETTY_FUNCTION__;
|
||||
tmp->f.data = tmp->outbuf;
|
||||
tmp->tail = 0;
|
||||
return &tmp->f;
|
||||
}
|
||||
|
||||
/*
|
||||
* LinToAdpcm_FrameIn
|
||||
* Fill an input buffer with 16-bit signed linear PCM values.
|
||||
*
|
||||
* Results:
|
||||
* None.
|
||||
*
|
||||
* Side effects:
|
||||
* tmp->tail is number of signal values in the input buffer.
|
||||
*/
|
||||
|
||||
static int
|
||||
lintoadpcm_framein (struct ast_translator_pvt *pvt, struct ast_frame *f)
|
||||
{
|
||||
struct adpcm_encoder_pvt *tmp = (struct adpcm_encoder_pvt *) pvt;
|
||||
|
||||
if ((tmp->tail + f->datalen / 2) < (sizeof (tmp->inbuf) / 2))
|
||||
{
|
||||
memcpy (&tmp->inbuf[tmp->tail], f->data, f->datalen);
|
||||
tmp->tail += f->datalen / 2;
|
||||
}
|
||||
else
|
||||
{
|
||||
ast_log (LOG_WARNING, "Out of buffer space\n");
|
||||
return -1;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* LinToAdpcm_FrameOut
|
||||
* Convert a buffer of raw 16-bit signed linear PCM to a buffer
|
||||
* of 4-bit ADPCM packed two to a byte (Big Endian).
|
||||
*
|
||||
* Results:
|
||||
* Foo
|
||||
*
|
||||
* Side effects:
|
||||
* Leftover inbuf data gets packed, tail gets updated.
|
||||
*/
|
||||
|
||||
static struct ast_frame *
|
||||
lintoadpcm_frameout (struct ast_translator_pvt *pvt)
|
||||
{
|
||||
struct adpcm_encoder_pvt *tmp = (struct adpcm_encoder_pvt *) pvt;
|
||||
unsigned char adpcm0, adpcm1;
|
||||
int i_max, i;
|
||||
|
||||
if (tmp->tail < 2) return NULL;
|
||||
|
||||
|
||||
i_max = (tmp->tail / 2) * 2;
|
||||
|
||||
tmp->outbuf[0] = tmp->ssindex & 0xff;
|
||||
tmp->outbuf[1] = (tmp->signal >> 8) & 0xff;
|
||||
tmp->outbuf[2] = (tmp->signal & 0xff);
|
||||
|
||||
for (i = 0; i < i_max; i+=2)
|
||||
{
|
||||
adpcm0 = adpcm(tmp->inbuf[i], &tmp->ssindex, &tmp->signal);
|
||||
adpcm1 = adpcm(tmp->inbuf[i+1], &tmp->ssindex, &tmp->signal);
|
||||
tmp->outbuf[i/2 + 3] = (adpcm0 << 4) | adpcm1;
|
||||
};
|
||||
|
||||
|
||||
tmp->f.frametype = AST_FRAME_VOICE;
|
||||
tmp->f.subclass = AST_FORMAT_ADPCM;
|
||||
tmp->f.timelen = i_max / 8;
|
||||
tmp->f.mallocd = 0;
|
||||
tmp->f.offset = AST_FRIENDLY_OFFSET;
|
||||
tmp->f.src = __PRETTY_FUNCTION__;
|
||||
tmp->f.data = tmp->outbuf;
|
||||
tmp->f.datalen = i_max / 2 + 3;
|
||||
|
||||
/*
|
||||
* If there is a signal left over (there should be no more than
|
||||
* one) move it to the beginning of the input buffer.
|
||||
*/
|
||||
|
||||
if (tmp->tail == i_max)
|
||||
tmp->tail = 0;
|
||||
else
|
||||
{
|
||||
tmp->inbuf[0] = tmp->inbuf[tmp->tail];
|
||||
tmp->tail = 1;
|
||||
}
|
||||
return &tmp->f;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* AdpcmToLin_Sample
|
||||
*/
|
||||
|
||||
static struct ast_frame *
|
||||
adpcmtolin_sample ()
|
||||
{
|
||||
static struct ast_frame f;
|
||||
f.frametype = AST_FRAME_VOICE;
|
||||
f.subclass = AST_FORMAT_ADPCM;
|
||||
f.datalen = sizeof (adpcm_slin_ex);
|
||||
f.timelen = sizeof(adpcm_slin_ex) / 4;
|
||||
f.mallocd = 0;
|
||||
f.offset = 0;
|
||||
f.src = __PRETTY_FUNCTION__;
|
||||
f.data = adpcm_slin_ex;
|
||||
return &f;
|
||||
}
|
||||
|
||||
/*
|
||||
* LinToAdpcm_Sample
|
||||
*/
|
||||
|
||||
static struct ast_frame *
|
||||
lintoadpcm_sample ()
|
||||
{
|
||||
static struct ast_frame f;
|
||||
f.frametype = AST_FRAME_VOICE;
|
||||
f.subclass = AST_FORMAT_SLINEAR;
|
||||
f.datalen = sizeof (slin_adpcm_ex);
|
||||
/* Assume 8000 Hz */
|
||||
f.timelen = sizeof (slin_adpcm_ex) / 16;
|
||||
f.mallocd = 0;
|
||||
f.offset = 0;
|
||||
f.src = __PRETTY_FUNCTION__;
|
||||
f.data = slin_adpcm_ex;
|
||||
return &f;
|
||||
}
|
||||
|
||||
/*
|
||||
* Adpcm_Destroy
|
||||
* Destroys a private workspace.
|
||||
*
|
||||
* Results:
|
||||
* It's gone!
|
||||
*
|
||||
* Side effects:
|
||||
* None.
|
||||
*/
|
||||
|
||||
static void
|
||||
adpcm_destroy (struct ast_translator_pvt *pvt)
|
||||
{
|
||||
free (pvt);
|
||||
localusecnt--;
|
||||
ast_update_use_count ();
|
||||
}
|
||||
|
||||
/*
|
||||
* The complete translator for ADPCMToLin.
|
||||
*/
|
||||
|
||||
static struct ast_translator adpcmtolin = {
|
||||
"adpcmtolin",
|
||||
AST_FORMAT_ADPCM,
|
||||
AST_FORMAT_SLINEAR,
|
||||
adpcmtolin_new,
|
||||
adpcmtolin_framein,
|
||||
adpcmtolin_frameout,
|
||||
adpcm_destroy,
|
||||
/* NULL */
|
||||
adpcmtolin_sample
|
||||
};
|
||||
|
||||
/*
|
||||
* The complete translator for LinToADPCM.
|
||||
*/
|
||||
|
||||
static struct ast_translator lintoadpcm = {
|
||||
"lintoadpcm",
|
||||
AST_FORMAT_SLINEAR,
|
||||
AST_FORMAT_ADPCM,
|
||||
lintoadpcm_new,
|
||||
lintoadpcm_framein,
|
||||
lintoadpcm_frameout,
|
||||
adpcm_destroy,
|
||||
/* NULL */
|
||||
lintoadpcm_sample
|
||||
};
|
||||
|
||||
int
|
||||
unload_module (void)
|
||||
{
|
||||
int res;
|
||||
pthread_mutex_lock (&localuser_lock);
|
||||
res = ast_unregister_translator (&lintoadpcm);
|
||||
if (!res)
|
||||
res = ast_unregister_translator (&adpcmtolin);
|
||||
if (localusecnt)
|
||||
res = -1;
|
||||
pthread_mutex_unlock (&localuser_lock);
|
||||
return res;
|
||||
}
|
||||
|
||||
int
|
||||
load_module (void)
|
||||
{
|
||||
int res;
|
||||
res = ast_register_translator (&adpcmtolin);
|
||||
if (!res)
|
||||
res = ast_register_translator (&lintoadpcm);
|
||||
else
|
||||
ast_unregister_translator (&adpcmtolin);
|
||||
return res;
|
||||
}
|
||||
|
||||
/*
|
||||
* Return a description of this module.
|
||||
*/
|
||||
|
||||
char *
|
||||
description (void)
|
||||
{
|
||||
return tdesc;
|
||||
}
|
||||
|
||||
int
|
||||
usecount (void)
|
||||
{
|
||||
int res;
|
||||
STANDARD_USECOUNT (res);
|
||||
return res;
|
||||
}
|
||||
|
||||
char *
|
||||
key ()
|
||||
{
|
||||
return ASTERISK_GPL_KEY;
|
||||
}
|
||||
@ -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;
|
||||
}
|
||||
Loading…
Reference in new issue