/* * CallWeaver -- An open source telephony toolkit. * * Copyright (C) 1999 - 2005, Digium, Inc. * * Mark Spencer * * See http://www.callweaver.org for more information about * the CallWeaver 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_ulaw.c - translate between signed linear and ulaw * */ #include #include #include #include #include #include #define SPANDSP_EXPOSE_INTERNAL_STRUCTURES #include #include "callweaver.h" CALLWEAVER_FILE_VERSION("$HeadURL$", "$Revision$") #include "callweaver/lock.h" #include "callweaver/logger.h" #include "callweaver/module.h" #include "callweaver/config.h" #include "callweaver/options.h" #include "callweaver/channel.h" #include "core/translate.h" #include "callweaver/translate.h" #include "callweaver/callweaver_pcm.h" #define BUFFER_SIZE 8096 /* size for the translation buffers */ static int useplc = 0; /* Sample 10ms of ulaw frame data */ static uint8_t ulaw_slin_ex[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; /*! * \brief Private workspace for translating signed linear signals to ulaw. */ struct ulaw_encoder_pvt { struct cw_frame f; char offset[CW_FRIENDLY_OFFSET]; /*!< Space to build offset */ uint8_t outbuf[BUFFER_SIZE]; /*!< Encoded ulaw, two nibbles to a word */ int tail; }; /*! * \brief Private workspace for translating ulaw signals to signed linear. */ struct ulaw_decoder_pvt { struct cw_frame f; char offset[CW_FRIENDLY_OFFSET]; /*!< Space to build offset */ int16_t outbuf[BUFFER_SIZE]; /*!< Decoded signed linear values */ int tail; plc_state_t plc; }; /*! * \brief ulawtolin_new * Create a new instance of ulaw_decoder_pvt. * * Results: * Returns a pointer to the new instance. * * Side effects: * None. */ static void *ulawtolin_new(void) { struct ulaw_decoder_pvt *tmp; if ((tmp = malloc(sizeof(struct ulaw_decoder_pvt))) == NULL) return NULL; memset(tmp, 0, sizeof(*tmp)); plc_init(&tmp->plc); return tmp; } /*! * \brief lintoulaw_new * Create a new instance of ulaw_encoder_pvt. * * Results: * Returns a pointer to the new instance. * * Side effects: * None. */ static void *lintoulaw_new(void) { struct ulaw_encoder_pvt *tmp; if ((tmp = malloc(sizeof(struct ulaw_encoder_pvt))) == NULL) return NULL; memset(tmp, 0, sizeof(*tmp)); tmp->tail = 0; return tmp; } /*! * \brief ulawtolin_framein * Fill an input buffer with packed 4-bit ulaw values if there is room * left. * * Results: * Foo * * Side effects: * tmp->tail is the number of packed values in the buffer. */ static int ulawtolin_framein(void *pvt, struct cw_frame *f) { struct ulaw_decoder_pvt *tmp = (struct ulaw_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(int16_t) > sizeof(tmp->outbuf)) { cw_log(CW_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 ((tmp->tail + f->datalen)*sizeof(int16_t) > sizeof(tmp->outbuf)) { cw_log(CW_LOG_WARNING, "Out of buffer space\n"); return -1; } /* Reset ssindex and signal to frame's specified values */ b = f->data; for (x = 0; x < f->datalen; x++) tmp->outbuf[tmp->tail + x] = CW_MULAW(b[x]); if (useplc) plc_rx(&tmp->plc, tmp->outbuf+tmp->tail, f->datalen); tmp->tail += f->datalen; return 0; } /*! * \brief ulawtolin_frameout * Convert 4-bit ulaw 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 cw_frame *ulawtolin_frameout(void *pvt) { struct ulaw_decoder_pvt *tmp = (struct ulaw_decoder_pvt *) pvt; if (tmp->tail == 0) return NULL; cw_fr_init_ex(&tmp->f, CW_FRAME_VOICE, CW_FORMAT_SLINEAR); tmp->f.datalen = tmp->tail*sizeof(int16_t); tmp->f.samples = tmp->tail; tmp->f.offset = CW_FRIENDLY_OFFSET; tmp->f.data = tmp->outbuf; tmp->tail = 0; return &tmp->f; } /*! * \brief lintoulaw_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 lintoulaw_framein(void *pvt, struct cw_frame *f) { struct ulaw_encoder_pvt *tmp = (struct ulaw_encoder_pvt *) pvt; int x; int16_t *s; if (tmp->tail + f->datalen/sizeof(int16_t) >= sizeof(tmp->outbuf)) { cw_log(CW_LOG_WARNING, "Out of buffer space\n"); return -1; } s = f->data; for (x = 0; x < f->datalen/sizeof(int16_t); x++) tmp->outbuf[x + tmp->tail] = CW_LIN2MU(s[x]); tmp->tail += f->datalen/sizeof(int16_t); return 0; } /*! * \brief lintoulaw_frameout * Convert a buffer of raw 16-bit signed linear PCM to a buffer * of 4-bit ulaw packed two to a byte (Big Endian). * * Results: * Foo * * Side effects: * Leftover inbuf data gets packed, tail gets updated. */ static struct cw_frame *lintoulaw_frameout(void *pvt) { struct ulaw_encoder_pvt *tmp = (struct ulaw_encoder_pvt *) pvt; if (tmp->tail == 0) return NULL; cw_fr_init_ex(&tmp->f, CW_FRAME_VOICE, CW_FORMAT_ULAW); tmp->f.samples = tmp->tail; tmp->f.offset = CW_FRIENDLY_OFFSET; tmp->f.data = tmp->outbuf; tmp->f.datalen = tmp->tail; tmp->tail = 0; return &tmp->f; } /*! * \brief ulawtolin_sample */ static struct cw_frame *ulawtolin_sample(int *i) { static struct cw_frame f; CW_UNUSED(i); cw_fr_init_ex(&f, CW_FRAME_VOICE, CW_FORMAT_ULAW); f.datalen = sizeof (ulaw_slin_ex); f.samples = sizeof(ulaw_slin_ex); f.data = ulaw_slin_ex; return &f; } /*! * \brief The complete translator for ulawtolin. */ static cw_translator_t ulawtolin = { .name = "ulawtolin", .src_format = CW_FORMAT_ULAW, .src_rate = 8000, .dst_format = CW_FORMAT_SLINEAR, .dst_rate = 8000, .newpvt = ulawtolin_new, .framein = ulawtolin_framein, .frameout = ulawtolin_frameout, .destroy = free, .sample = ulawtolin_sample }; /*! * \brief The complete translator for lintoulaw. */ static cw_translator_t lintoulaw = { .name = "lintoulaw", .src_format = CW_FORMAT_SLINEAR, .src_rate = 8000, .dst_format = CW_FORMAT_ULAW, .dst_rate = 8000, .newpvt = lintoulaw_new, .framein = lintoulaw_framein, .frameout = lintoulaw_frameout, .destroy = free, .sample = cw_translate_linear_sample }; static void parse_config(void) { struct cw_config *cfg; struct cw_variable *var; if ((cfg = cw_config_load("codecs.conf"))) { if ((var = cw_variable_browse(cfg, "plc"))) { while (var) { if (!strcasecmp(var->name, "genericplc")) { useplc = cw_true(var->value) ? 1 : 0; if (option_verbose > 2) cw_verbose(VERBOSE_PREFIX_3 "codec_ulaw: %susing generic PLC\n", useplc ? "" : "not "); } var = var->next; } } cw_config_destroy(cfg); } } static int reload_module(void) { parse_config(); return 0; } static int unload_module(void) { cw_translator_unregister(&ulawtolin); cw_translator_unregister(&lintoulaw); return 0; } static int load_module(void) { parse_config(); cw_translator_register(&ulawtolin); cw_translator_register(&lintoulaw); return 0; } MODULE_INFO(load_module, reload_module, unload_module, NULL, "Mu-law to/from PCM16 translator")