627 lines
12 KiB
C
627 lines
12 KiB
C
/*
|
|
* Asterisk -- An open source telephony toolkit.
|
|
*
|
|
* Based on frompcm.c and topcm.c from the Emiliano MIPL browser/
|
|
* interpreter. See http://www.bsdtelephony.com.mx
|
|
*
|
|
* Copyright (c) 2001 - 2005 Digium, Inc.
|
|
* All rights reserved.
|
|
*
|
|
* Karl Sackett <krs@linux-support.net>, 2001-03-21
|
|
*
|
|
* See http://www.asterisk.org for more information about
|
|
* the Asterisk project. Please do not directly contact
|
|
* any of the maintainers of this project for assistance;
|
|
* the project provides a web site, mailing lists and IRC
|
|
* channels for your use.
|
|
*
|
|
* This program is free software, distributed under the terms of
|
|
* the GNU General Public License Version 2. See the LICENSE file
|
|
* at the top of the source tree.
|
|
*/
|
|
|
|
/*! \file
|
|
*
|
|
* \brief codec_adpcm.c - translate between signed linear and Dialogic ADPCM
|
|
*
|
|
* \ingroup codecs
|
|
*/
|
|
|
|
#include <fcntl.h>
|
|
#include <netinet/in.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
#include "asterisk.h"
|
|
|
|
ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
|
|
|
|
#include "asterisk/lock.h"
|
|
#include "asterisk/logger.h"
|
|
#include "asterisk/module.h"
|
|
#include "asterisk/config.h"
|
|
#include "asterisk/options.h"
|
|
#include "asterisk/translate.h"
|
|
#include "asterisk/channel.h"
|
|
#include "asterisk/utils.h"
|
|
|
|
/* define NOT_BLI to use a faster but not bit-level identical version */
|
|
/* #define NOT_BLI */
|
|
|
|
#define BUFFER_SIZE 8096 /* size for the translation buffers */
|
|
|
|
AST_MUTEX_DEFINE_STATIC(localuser_lock);
|
|
static int localusecnt = 0;
|
|
|
|
static char *tdesc = "Adaptive Differential PCM Coder/Decoder";
|
|
|
|
static int useplc = 0;
|
|
|
|
/* Sample frame data */
|
|
|
|
#include "slin_adpcm_ex.h"
|
|
#include "adpcm_slin_ex.h"
|
|
|
|
/*
|
|
* Step size index shift table
|
|
*/
|
|
|
|
static int indsft[8] = { -1, -1, -1, -1, 2, 4, 6, 8 };
|
|
|
|
/*
|
|
* Step size table, where stpsz[i]=floor[16*(11/10)^i]
|
|
*/
|
|
|
|
static int 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
|
|
};
|
|
|
|
/*
|
|
* Decoder/Encoder state
|
|
* States for both encoder and decoder are synchronized
|
|
*/
|
|
struct adpcm_state {
|
|
int ssindex;
|
|
int signal;
|
|
int zero_count;
|
|
int next_flag;
|
|
};
|
|
|
|
/*
|
|
* 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(int encoded, struct adpcm_state *state)
|
|
{
|
|
int diff;
|
|
int step;
|
|
int sign;
|
|
|
|
step = stpsz[state->ssindex];
|
|
|
|
sign = encoded & 0x08;
|
|
encoded &= 0x07;
|
|
#ifdef NOT_BLI
|
|
diff = (((encoded << 1) + 1) * step) >> 3;
|
|
#else /* BLI code */
|
|
diff = step >> 3;
|
|
if (encoded & 4)
|
|
diff += step;
|
|
if (encoded & 2)
|
|
diff += step >> 1;
|
|
if (encoded & 1)
|
|
diff += step >> 2;
|
|
if ((encoded >> 1) & step & 0x1)
|
|
diff++;
|
|
#endif
|
|
if (sign)
|
|
diff = -diff;
|
|
|
|
if (state->next_flag & 0x1)
|
|
state->signal -= 8;
|
|
else if (state->next_flag & 0x2)
|
|
state->signal += 8;
|
|
|
|
state->signal += diff;
|
|
|
|
if (state->signal > 2047)
|
|
state->signal = 2047;
|
|
else if (state->signal < -2047)
|
|
state->signal = -2047;
|
|
|
|
state->next_flag = 0;
|
|
|
|
#ifdef AUTO_RETURN
|
|
if (encoded)
|
|
state->zero_count = 0;
|
|
else if (++(state->zero_count) == 24) {
|
|
state->zero_count = 0;
|
|
if (state->signal > 0)
|
|
state->next_flag = 0x1;
|
|
else if (state->signal < 0)
|
|
state->next_flag = 0x2;
|
|
}
|
|
#endif
|
|
|
|
state->ssindex += indsft[encoded];
|
|
if (state->ssindex < 0)
|
|
state->ssindex = 0;
|
|
else if (state->ssindex > 48)
|
|
state->ssindex = 48;
|
|
|
|
return state->signal << 4;
|
|
}
|
|
|
|
/*
|
|
* 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 int adpcm(short csig, struct adpcm_state *state)
|
|
{
|
|
int diff;
|
|
int step;
|
|
int encoded;
|
|
|
|
/*
|
|
* Clip csig if too large or too small
|
|
*/
|
|
csig >>= 4;
|
|
|
|
step = stpsz[state->ssindex];
|
|
diff = csig - state->signal;
|
|
|
|
#ifdef NOT_BLI
|
|
if (diff < 0) {
|
|
encoded = (-diff << 2) / step;
|
|
if (encoded > 7)
|
|
encoded = 7;
|
|
encoded |= 0x08;
|
|
} else {
|
|
encoded = (diff << 2) / step;
|
|
if (encoded > 7)
|
|
encoded = 7;
|
|
}
|
|
#else /* BLI code */
|
|
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;
|
|
#endif /* NOT_BLI */
|
|
|
|
/* feedback to state */
|
|
decode(encoded, state);
|
|
|
|
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 */
|
|
struct adpcm_state state;
|
|
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 */
|
|
struct adpcm_state state;
|
|
int tail;
|
|
plc_state_t plc;
|
|
};
|
|
|
|
/*
|
|
* 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(void)
|
|
{
|
|
struct adpcm_decoder_pvt *tmp;
|
|
|
|
if ((tmp = ast_calloc(1, sizeof(*tmp)))) {
|
|
tmp->tail = 0;
|
|
plc_init(&tmp->plc);
|
|
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(void)
|
|
{
|
|
struct adpcm_encoder_pvt *tmp;
|
|
|
|
if ((tmp = ast_calloc(1, sizeof(*tmp)))) {
|
|
localusecnt++;
|
|
ast_update_use_count();
|
|
tmp->tail = 0;
|
|
}
|
|
|
|
return (struct ast_translator_pvt *)tmp;
|
|
}
|
|
|
|
/*
|
|
* AdpcmToLin_FrameIn
|
|
* Take an input buffer with packed 4-bit ADPCM values and put decoded PCM in outbuf,
|
|
* 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;
|
|
unsigned char *b;
|
|
|
|
if(f->datalen == 0) { /* perform PLC with nominal framesize of 20ms/160 samples */
|
|
if((tmp->tail + 160) > sizeof(tmp->outbuf) / 2) {
|
|
ast_log(LOG_WARNING, "Out of buffer space\n");
|
|
return -1;
|
|
}
|
|
if(useplc) {
|
|
plc_fillin(&tmp->plc, tmp->outbuf+tmp->tail, 160);
|
|
tmp->tail += 160;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
if (f->datalen * 4 + tmp->tail * 2 > sizeof(tmp->outbuf)) {
|
|
ast_log(LOG_WARNING, "Out of buffer space\n");
|
|
return -1;
|
|
}
|
|
|
|
b = f->data;
|
|
|
|
for (x=0;x<f->datalen;x++) {
|
|
tmp->outbuf[tmp->tail++] = decode((b[x] >> 4) & 0xf, &tmp->state);
|
|
tmp->outbuf[tmp->tail++] = decode(b[x] & 0x0f, &tmp->state);
|
|
}
|
|
|
|
if(useplc)
|
|
plc_rx(&tmp->plc, tmp->outbuf+tmp->tail-f->datalen*2, f->datalen*2);
|
|
|
|
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.samples 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.samples = tmp->tail;
|
|
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;
|
|
int i_max, i;
|
|
|
|
if (tmp->tail < 2)
|
|
return NULL;
|
|
|
|
i_max = tmp->tail & ~1; /* atomic size is 2 samples */
|
|
|
|
/* What is this, state debugging? should be #ifdef'd then
|
|
tmp->outbuf[0] = tmp->ssindex & 0xff;
|
|
tmp->outbuf[1] = (tmp->signal >> 8) & 0xff;
|
|
tmp->outbuf[2] = (tmp->signal & 0xff);
|
|
tmp->outbuf[3] = tmp->zero_count;
|
|
tmp->outbuf[4] = tmp->next_flag;
|
|
*/
|
|
for (i = 0; i < i_max; i+=2) {
|
|
tmp->outbuf[i/2] =
|
|
(adpcm(tmp->inbuf[i ], &tmp->state) << 4) |
|
|
(adpcm(tmp->inbuf[i+1], &tmp->state) );
|
|
};
|
|
|
|
tmp->f.frametype = AST_FRAME_VOICE;
|
|
tmp->f.subclass = AST_FORMAT_ADPCM;
|
|
tmp->f.samples = i_max;
|
|
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;
|
|
|
|
/*
|
|
* 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(void)
|
|
{
|
|
static struct ast_frame f;
|
|
f.frametype = AST_FRAME_VOICE;
|
|
f.subclass = AST_FORMAT_ADPCM;
|
|
f.datalen = sizeof(adpcm_slin_ex);
|
|
f.samples = sizeof(adpcm_slin_ex) * 2;
|
|
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(void)
|
|
{
|
|
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.samples = sizeof(slin_adpcm_ex) / 2;
|
|
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
|
|
};
|
|
|
|
static void parse_config(void)
|
|
{
|
|
struct ast_config *cfg;
|
|
struct ast_variable *var;
|
|
if ((cfg = ast_config_load("codecs.conf"))) {
|
|
if ((var = ast_variable_browse(cfg, "plc"))) {
|
|
while (var) {
|
|
if (!strcasecmp(var->name, "genericplc")) {
|
|
useplc = ast_true(var->value) ? 1 : 0;
|
|
if (option_verbose > 2)
|
|
ast_verbose(VERBOSE_PREFIX_3 "codec_adpcm: %susing generic PLC\n", useplc ? "" : "not ");
|
|
}
|
|
var = var->next;
|
|
}
|
|
}
|
|
ast_config_destroy(cfg);
|
|
}
|
|
}
|
|
|
|
int reload(void)
|
|
{
|
|
parse_config();
|
|
return 0;
|
|
}
|
|
|
|
int unload_module(void)
|
|
{
|
|
int res;
|
|
ast_mutex_lock(&localuser_lock);
|
|
res = ast_unregister_translator(&lintoadpcm);
|
|
if (!res)
|
|
res = ast_unregister_translator(&adpcmtolin);
|
|
if (localusecnt)
|
|
res = -1;
|
|
ast_mutex_unlock(&localuser_lock);
|
|
return res;
|
|
}
|
|
|
|
int load_module(void)
|
|
{
|
|
int res;
|
|
parse_config();
|
|
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;
|
|
}
|