mirror of https://github.com/asterisk/asterisk
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@191 65c4cc65-6c06-0410-ace0-fbb531ad65f31.0
Mark Spencer
26 years ago
parent
c340c2093c
commit
2ebdf66e5f
@ -0,0 +1,348 @@
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/*
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* Asterisk -- A telephony toolkit for Linux.
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*
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* Translate between signed linear and LPC10 (Linear Predictor Code)
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*
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* The lpc10 code is from a library used by nautilus, modified to be a bit
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* nicer to the compiler.
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*
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* See http://www.arl.wustl.edu/~jaf/
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*
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* Copyright (C) 1999, Mark Spencer
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*
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* Mark Spencer <markster@linux-support.net>
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*
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* This program is free software, distributed under the terms of
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* the GNU General Public License
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*/
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#include <asterisk/translate.h>
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#include <asterisk/module.h>
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#include <asterisk/logger.h>
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#include <pthread.h>
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#include <fcntl.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <netinet/in.h>
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#include <string.h>
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#include <stdio.h>
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#include "lpc10/lpc10.h"
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/* Sample frame data */
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#include "slin_lpc10_ex.h"
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#include "lpc10_slin_ex.h"
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/* We use a very strange format here... I have no idea why... The frames are 180
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samples long, which isn't even an even number of milliseconds... Not only that
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but we hvae to waste two bits of each frame to keep them ending on a byte boundary
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because the frames are 54 bits long */
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#define LPC10_BYTES_IN_COMPRESSED_FRAME (LPC10_BITS_IN_COMPRESSED_FRAME + 7)/8
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static pthread_mutex_t localuser_lock = PTHREAD_MUTEX_INITIALIZER;
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static int localusecnt=0;
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static char *tdesc = "LPC10 2.4kbps (signed linear) Voice Coder";
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struct ast_translator_pvt {
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union {
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struct lpc10_encoder_state *enc;
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struct lpc10_decoder_state *dec;
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} lpc10;
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struct ast_frame f;
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/* Space to build offset */
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char offset[AST_FRIENDLY_OFFSET];
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/* Buffer for our outgoing frame */
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short outbuf[LPC10_SAMPLES_PER_FRAME];
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/* Enough to store a full second */
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short buf[8000];
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int tail;
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int longer;
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};
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#define lpc10_coder_pvt ast_translator_pvt
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static struct ast_translator_pvt *lpc10_enc_new()
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{
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struct lpc10_coder_pvt *tmp;
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tmp = malloc(sizeof(struct lpc10_coder_pvt));
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if (tmp) {
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if (!(tmp->lpc10.enc = create_lpc10_encoder_state())) {
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free(tmp);
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tmp = NULL;
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}
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tmp->tail = 0;
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tmp->longer = 0;
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localusecnt++;
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}
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return tmp;
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}
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static struct ast_translator_pvt *lpc10_dec_new()
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{
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struct lpc10_coder_pvt *tmp;
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tmp = malloc(sizeof(struct lpc10_coder_pvt));
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if (tmp) {
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if (!(tmp->lpc10.dec = create_lpc10_decoder_state())) {
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free(tmp);
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tmp = NULL;
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}
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tmp->tail = 0;
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tmp->longer = 0;
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localusecnt++;
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}
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return tmp;
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}
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static struct ast_frame *lintolpc10_sample()
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{
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static struct ast_frame f;
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static int longer = 0;
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f.frametype = AST_FRAME_VOICE;
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f.subclass = AST_FORMAT_SLINEAR;
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f.datalen = sizeof(slin_lpc10_ex);
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/* Assume 8000 Hz */
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f.timelen = LPC10_SAMPLES_PER_FRAME/8;
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f.timelen += longer;
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longer = 1- longer;
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f.mallocd = 0;
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f.offset = 0;
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f.src = __PRETTY_FUNCTION__;
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f.data = slin_lpc10_ex;
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return &f;
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}
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static struct ast_frame *lpc10tolin_sample()
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{
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static struct ast_frame f;
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f.frametype = AST_FRAME_VOICE;
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f.subclass = AST_FORMAT_LPC10;
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f.datalen = sizeof(lpc10_slin_ex);
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/* All frames are 22 ms long (maybe a little more -- why did he choose
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LPC10_SAMPLES_PER_FRAME sample frames anyway?? */
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f.timelen = LPC10_SAMPLES_PER_FRAME/8;
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f.mallocd = 0;
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f.offset = 0;
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f.src = __PRETTY_FUNCTION__;
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f.data = lpc10_slin_ex;
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return &f;
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}
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static struct ast_frame *lpc10tolin_frameout(struct ast_translator_pvt *tmp)
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{
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if (!tmp->tail)
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return NULL;
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/* Signed linear is no particular frame size, so just send whatever
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we have in the buffer in one lump sum */
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tmp->f.frametype = AST_FRAME_VOICE;
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tmp->f.subclass = AST_FORMAT_SLINEAR;
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tmp->f.datalen = tmp->tail * 2;
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/* Assume 8000 Hz */
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tmp->f.timelen = tmp->tail / 8;
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tmp->f.mallocd = 0;
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tmp->f.offset = AST_FRIENDLY_OFFSET;
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tmp->f.src = __PRETTY_FUNCTION__;
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tmp->f.data = tmp->buf;
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/* Reset tail pointer */
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tmp->tail = 0;
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#if 0
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/* Save a sample frame */
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{ static int samplefr = 0;
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if (samplefr == 80) {
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int fd;
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fd = open("lpc10.example", O_WRONLY | O_CREAT, 0644);
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write(fd, tmp->f.data, tmp->f.datalen);
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close(fd);
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}
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samplefr++;
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}
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#endif
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return &tmp->f;
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}
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static void extract_bits(INT32 *bits, unsigned char *c)
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{
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int x;
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for (x=0;x<LPC10_BITS_IN_COMPRESSED_FRAME;x++) {
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if (*c & (0x80 >> (x & 7)))
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bits[x] = 1;
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else
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bits[x] = 0;
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if ((x & 7) == 7)
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c++;
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}
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}
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static void build_bits(unsigned char *c, INT32 *bits)
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{
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unsigned char mask=0x80;
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int x;
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*c = 0;
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for (x=0;x<LPC10_BITS_IN_COMPRESSED_FRAME;x++) {
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if (bits[x])
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*c |= mask;
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mask = mask >> 1;
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if ((x % 8)==7) {
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c++;
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*c = 0;
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mask = 0x80;
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}
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}
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}
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static int lpc10tolin_framein(struct ast_translator_pvt *tmp, struct ast_frame *f)
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{
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/* Assuming there's space left, decode into the current buffer at
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the tail location */
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int x;
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float tmpbuf[LPC10_SAMPLES_PER_FRAME];
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short *sd;
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INT32 bits[LPC10_BITS_IN_COMPRESSED_FRAME];
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if (tmp->tail + LPC10_SAMPLES_PER_FRAME < sizeof(tmp->buf)/2) {
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sd = tmp->buf + tmp->tail;
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extract_bits(bits, f->data);
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if (lpc10_decode(bits, tmpbuf, tmp->lpc10.dec)) {
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ast_log(LOG_WARNING, "Invalid lpc10 data\n");
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return -1;
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}
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for (x=0;x<LPC10_SAMPLES_PER_FRAME;x++) {
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/* Convert to a real between -1.0 and 1.0 */
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sd[x] = 32768.0 * tmpbuf[x];
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}
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tmp->tail+=LPC10_SAMPLES_PER_FRAME;
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} else {
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ast_log(LOG_WARNING, "Out of buffer space\n");
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return -1;
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}
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return 0;
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}
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static int lintolpc10_framein(struct ast_translator_pvt *tmp, struct ast_frame *f)
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{
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/* Just add the frames to our stream */
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/* XXX We should look at how old the rest of our stream is, and if it
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is too old, then we should overwrite it entirely, otherwise we can
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get artifacts of earlier talk that do not belong */
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if (tmp->tail + f->datalen < sizeof(tmp->buf) / 2) {
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memcpy((tmp->buf + tmp->tail), f->data, f->datalen);
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tmp->tail += f->datalen/2;
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} else {
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ast_log(LOG_WARNING, "Out of buffer space\n");
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return -1;
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}
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return 0;
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}
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static struct ast_frame *lintolpc10_frameout(struct ast_translator_pvt *tmp)
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{
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int x;
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float tmpbuf[LPC10_SAMPLES_PER_FRAME];
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INT32 bits[LPC10_BITS_IN_COMPRESSED_FRAME];
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/* We can't work on anything less than a frame in size */
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if (tmp->tail < LPC10_SAMPLES_PER_FRAME)
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return NULL;
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/* Encode a frame of data */
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for (x=0;x<LPC10_SAMPLES_PER_FRAME;x++) {
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tmpbuf[x] = (float)tmp->buf[x] / 32768.0;
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}
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lpc10_encode(tmpbuf, bits, tmp->lpc10.enc);
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build_bits((unsigned char *)tmp->outbuf, bits);
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tmp->f.frametype = AST_FRAME_VOICE;
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tmp->f.subclass = AST_FORMAT_LPC10;
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tmp->f.datalen = LPC10_BYTES_IN_COMPRESSED_FRAME;
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tmp->f.timelen = 22;
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/* We alternate between 22 and 23 ms to simulate 22.5 ms */
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tmp->f.timelen += tmp->longer;
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/* Use one of the two left over bits to record if this is a 22 or 23 ms frame...
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important for IAX use */
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tmp->longer = 1 - tmp->longer;
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tmp->f.mallocd = 0;
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tmp->f.offset = AST_FRIENDLY_OFFSET;
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tmp->f.src = __PRETTY_FUNCTION__;
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tmp->f.data = tmp->outbuf;
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((char *)(tmp->f.data))[LPC10_BYTES_IN_COMPRESSED_FRAME - 1] |= tmp->longer;
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tmp->tail -= LPC10_SAMPLES_PER_FRAME;
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/* Move the data at the end of the buffer to the front */
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if (tmp->tail)
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memmove(tmp->buf, tmp->buf + LPC10_SAMPLES_PER_FRAME, tmp->tail * 2);
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#if 0
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/* Save a sample frame */
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{ static int samplefr = 0;
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if (samplefr == 0) {
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int fd;
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fd = open("lpc10.example", O_WRONLY | O_CREAT, 0644);
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write(fd, tmp->f.data, tmp->f.datalen);
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close(fd);
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}
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samplefr++;
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}
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#endif
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return &tmp->f;
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}
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static void lpc10_destroy(struct ast_translator_pvt *pvt)
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{
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/* Enc and DEC are both just allocated, so they can be freed */
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free(pvt->lpc10.enc);
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free(pvt);
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localusecnt--;
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}
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static struct ast_translator lpc10tolin =
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{ "lpc10tolin",
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AST_FORMAT_LPC10, AST_FORMAT_SLINEAR,
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lpc10_dec_new,
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lpc10tolin_framein,
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lpc10tolin_frameout,
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lpc10_destroy,
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lpc10tolin_sample
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};
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static struct ast_translator lintolpc10 =
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{ "lintolpc10",
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AST_FORMAT_SLINEAR, AST_FORMAT_LPC10,
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lpc10_enc_new,
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lintolpc10_framein,
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lintolpc10_frameout,
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lpc10_destroy,
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lintolpc10_sample
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};
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int unload_module(void)
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{
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int res;
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pthread_mutex_lock(&localuser_lock);
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res = ast_unregister_translator(&lintolpc10);
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if (!res)
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res = ast_unregister_translator(&lpc10tolin);
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if (localusecnt)
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res = -1;
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pthread_mutex_unlock(&localuser_lock);
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return res;
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}
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int load_module(void)
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{
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int res;
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res=ast_register_translator(&lpc10tolin);
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if (!res)
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res=ast_register_translator(&lintolpc10);
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else
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ast_unregister_translator(&lpc10tolin);
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return res;
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}
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char *description(void)
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{
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return tdesc;
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}
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int usecount(void)
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{
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int res;
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STANDARD_USECOUNT(res);
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return res;
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}
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@ -0,0 +1,13 @@
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/*
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* 8-bit raw data
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*
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* Source: example.lpc10
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*
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* Copyright (C) 1999, Mark Spencer and Linux Support Services
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*
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* Distributed under the terms of the GNU General Public License
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*
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*/
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static unsigned char lpc10_slin_ex[] = {
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0x1, 0x8, 0x31, 0x8, 0x31, 0x80, 0x30 };
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@ -0,0 +1,21 @@
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/*
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* Signed 16-bit audio data
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*
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* Source: example.slin
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*
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* Copyright (C) 1999, Mark Spencer and Linux Support Services
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*
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* Distributed under the terms of the GNU General Public License
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*
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*/
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static signed short slin_lpc10_ex[] = {
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000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000,
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000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000,
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000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000,
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000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000,
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000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000,
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000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000,
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000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000,
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000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000,
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000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000, 000000 };
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