/* * FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application * Copyright (C) 2010, Eric des Courtis * * Version: MPL 1.1 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * Eric des Courtis * Copyright (C) Benbria. All Rights Reserved. * * Contributor(s): * * Piotr Gregor : * Eric des Courtis * * mod_avmd.c -- Advanced Voicemail Detection Module * * This module detects single frequency tones (used in voicemail to denote * the moment caller's voice is started to be recorded, aka. beep sounds, * beeps) using modified DESA-2 algorithm. */ #include #include #include #include #include #include #ifdef WIN32 #include #define ISNAN(x) (!!(_isnan(x))) #else #define ISNAN(x) (isnan(x)) #endif #include "avmd_buffer.h" #include "avmd_desa2_tweaked.h" #include "avmd_sma_buf.h" #include "avmd_options.h" #ifdef AVMD_FAST_MATH #include "avmd_fast_acosf.h" #endif /*! Calculate how many audio samples per ms based on the rate */ #define SAMPLES_PER_MS(r, m) ((r) / (1000/(m))) /*! Minimum beep length */ #define BEEP_TIME (2) /*! How often to evaluate the output of desa2 in ms */ #define SINE_TIME (2*0.125) /*! How long in samples does desa2 results get evaluated */ #define SINE_LEN(r) SAMPLES_PER_MS((r), SINE_TIME) /*! How long in samples is the minimum beep length */ #define BEEP_LEN(r) SAMPLES_PER_MS((r), BEEP_TIME) /*! Number of points in desa2 sample */ #define P (5) /*! Guesstimate frame length in ms */ #define FRAME_TIME (20) /*! Length in samples of the frame (guesstimate) */ #define FRAME_LEN(r) SAMPLES_PER_MS((r), FRAME_TIME) /*! Conversion to Hertz */ #define TO_HZ(r, f) (((r) * (f)) / (2.0 * M_PI)) /*! Minimum beep frequency in Hertz */ #define MIN_FREQUENCY (300.0) /*! Minimum frequency as digital normalized frequency */ #define MIN_FREQUENCY_R(r) ((2.0 * M_PI * MIN_FREQUENCY) / (r)) /*! * Maximum beep frequency in Hertz * Note: The maximum frequency the DESA-2 algorithm can uniquely * identify is 0.25 of the sampling rate. All the frequencies * below that level are detected unambiguously. This means 2kHz * for 8kHz audio. All the frequencies above 0.25 sampling rate * will be aliased to some frequency below that threshold. * This is not a problem here as we are interested in detection * of any sine wave instead of detection of particular frequency. */ #define MAX_FREQUENCY (2500.0) /*! Maximum frequency as digital normalized frequency */ #define MAX_FREQUENCY_R(r) ((2.0 * M_PI * MAX_FREQUENCY) / (r)) /* decrease this value to eliminate false positives */ #define VARIANCE_THRESHOLD (0.00025) #ifdef AVMD_REQUIRE_CONTINUOUS_STREAK /* increase this value to eliminate false positives */ #define SAMPLES_CONSECUTIVE_STREAK 15 #endif /*! Syntax of the API call. */ #define AVMD_SYNTAX " " /*! Number of expected parameters in api call. */ #define AVMD_PARAMS 2 /*! FreeSWITCH CUSTOM event type. */ #define AVMD_EVENT_BEEP "avmd::beep" #define AVMD_CHAR_BUF_LEN 10 #define AVMD_BUF_LINEAR_LEN 160 /* Prototypes */ SWITCH_MODULE_SHUTDOWN_FUNCTION(mod_avmd_shutdown); SWITCH_MODULE_LOAD_FUNCTION(mod_avmd_load); SWITCH_MODULE_DEFINITION(mod_avmd, mod_avmd_load, mod_avmd_shutdown, NULL); SWITCH_STANDARD_API(avmd_api_main); SWITCH_STANDARD_APP(avmd_start_function); /*! Status of the beep detection */ typedef enum { BEEP_DETECTED, BEEP_NOTDETECTED } avmd_beep_state_t; /*! Data related to the current status of the beep */ typedef struct { avmd_beep_state_t beep_state; size_t last_beep; } avmd_state_t; /*! Type that holds session information pertinent to the avmd module. */ typedef struct { /*! Internal FreeSWITCH session. */ switch_core_session_t *session; uint32_t rate; circ_buffer_t b; sma_buffer_t sma_b; sma_buffer_t sqa_b; size_t pos; double f; /* freq_table_t ft; */ avmd_state_t state; switch_time_t start_time; #ifdef AVMD_REQUIRE_CONTINUOUS_STREAK size_t samples_streak; /* number of DESA samples in single streak without reset needed to validate SMA estimator */ #endif size_t sample_count; } avmd_session_t; static void avmd_process(avmd_session_t *session, switch_frame_t *frame); static switch_bool_t avmd_callback(switch_media_bug_t * bug, void *user_data, switch_abc_type_t type); static void init_avmd_session_data(avmd_session_t *avmd_session, switch_core_session_t *fs_session); /*! \brief The avmd session data initialization function. * @author Eric des Courtis * @param avmd_session A reference to a avmd session. * @param fs_session A reference to a FreeSWITCH session. */ static void init_avmd_session_data(avmd_session_t *avmd_session, switch_core_session_t *fs_session) { /*! This is a worst case sample rate estimate */ avmd_session->rate = 48000; INIT_CIRC_BUFFER(&avmd_session->b, (size_t)BEEP_LEN(avmd_session->rate), (size_t)FRAME_LEN(avmd_session->rate), fs_session); if (avmd_session->b.buf == NULL) { switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(fs_session), SWITCH_LOG_ERROR, "Failed to init avmd session." " Buffer error\n"); return; } avmd_session->session = fs_session; avmd_session->pos = 0; avmd_session->f = 0.0; avmd_session->state.last_beep = 0; avmd_session->state.beep_state = BEEP_NOTDETECTED; #ifdef AVMD_REQUIRE_CONTINUOUS_STREAK avmd_session->samples_streak = SAMPLES_CONSECUTIVE_STREAK; #endif avmd_session->sample_count = 0; INIT_SMA_BUFFER( &avmd_session->sma_b, BEEP_LEN(avmd_session->rate) / SINE_LEN(avmd_session->rate), fs_session ); INIT_SMA_BUFFER( &avmd_session->sqa_b, BEEP_LEN(avmd_session->rate) / SINE_LEN(avmd_session->rate), fs_session ); } /*! \brief The callback function that is called when new audio data becomes available. * * @author Eric des Courtis * @param bug A reference to the media bug. * @param user_data The session information for this call. * @param type The switch callback type. * @return The success or failure of the function. */ static switch_bool_t avmd_callback(switch_media_bug_t * bug, void *user_data, switch_abc_type_t type) { avmd_session_t *avmd_session; #ifdef AVMD_OUTBOUND_CHANNEL switch_codec_t *read_codec; #endif #ifdef AVMD_INBOUND_CHANNEL switch_codec_t *write_codec; #endif switch_frame_t *frame; switch_core_session_t *fs_session; avmd_session = (avmd_session_t *) user_data; if (avmd_session == NULL) { switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "No avmd session assigned!\n"); return SWITCH_FALSE; } fs_session = avmd_session->session; if (fs_session == NULL) { switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "No FreeSWITCH session assigned!\n"); return SWITCH_FALSE; } switch (type) { case SWITCH_ABC_TYPE_INIT: #ifdef AVMD_OUTBOUND_CHANNEL read_codec = switch_core_session_get_read_codec(fs_session); if (read_codec == NULL) { switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(fs_session), SWITCH_LOG_WARNING, "No read codec assigned, default session rate to 8000 samples/s\n"); avmd_session->rate = 8000; } else { if (read_codec->implementation == NULL) { switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(fs_session), SWITCH_LOG_WARNING, "No read codec implementation assigned, default session rate to 8000 samples/s\n"); avmd_session->rate = 8000; } else { avmd_session->rate = read_codec->implementation->samples_per_second; } } #endif #ifdef AVMD_INBOUND_CHANNEL write_codec = switch_core_session_get_write_codec(fs_session); if (write_codec == NULL) { switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(fs_session), SWITCH_LOG_WARNING, "No write codec assigned, default session rate to 8000 samples/s\n"); avmd_session->rate = 8000; } else { if (write_codec->implementation == NULL) { switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(fs_session), SWITCH_LOG_WARNING, "No write codec implementation assigned, default session rate to 8000 samples/s\n"); avmd_session->rate = 8000; } else { avmd_session->rate = write_codec->implementation->samples_per_second; } } #endif avmd_session->start_time = switch_micro_time_now(); /* avmd_session->vmd_codec.channels = * read_codec->implementation->number_of_channels; */ switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(fs_session),SWITCH_LOG_INFO, "Avmd session initialized, [%u] samples/s\n", avmd_session->rate); break; case SWITCH_ABC_TYPE_READ_REPLACE: frame = switch_core_media_bug_get_read_replace_frame(bug); avmd_process(avmd_session, frame); return SWITCH_TRUE; case SWITCH_ABC_TYPE_WRITE_REPLACE: frame = switch_core_media_bug_get_write_replace_frame(bug); avmd_process(avmd_session, frame); return SWITCH_TRUE; default: break; } return SWITCH_TRUE; } /*! \brief FreeSWITCH module loading function. * * @author Eric des Courtis * @par Modifications: Piotr Gregor * @return On success SWITCH_STATUS_SUCCES, * on failure SWITCH_STATUS_TERM. */ SWITCH_MODULE_LOAD_FUNCTION(mod_avmd_load) { #ifdef AVMD_FAST_MATH char err[150]; int ret; #endif switch_application_interface_t *app_interface; switch_api_interface_t *api_interface; /* connect my internal structure to the blank pointer passed to me */ *module_interface = switch_loadable_module_create_module_interface(pool, modname); if (switch_event_reserve_subclass(AVMD_EVENT_BEEP) != SWITCH_STATUS_SUCCESS) { switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Couldn't register subclass [%s]!\n", AVMD_EVENT_BEEP); return SWITCH_STATUS_TERM; } switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_NOTICE, "Advanced voicemail detection enabled\n"); #ifdef AVMD_FAST_MATH ret = init_fast_acosf(); if (ret != 0) { strerror_r(errno, err, 150); switch (ret) { case -1: switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Can't access file [%s], error [%s]\n", ACOS_TABLE_FILENAME, err); break; case -2: switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Error creating file [%s], error [%s]\n", ACOS_TABLE_FILENAME, err); break; case -3: switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Access rights are OK but can't open file [%s], error [%s]\n", ACOS_TABLE_FILENAME, err); break; case -4: switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Access rights are OK but can't mmap file [%s], error [%s]\n", ACOS_TABLE_FILENAME, err); break; default: switch_log_printf(SWITCH_CHANNEL_LOG,SWITCH_LOG_ERROR, "Unknown error [%d] while initializing fast cos table [%s], " "errno [%s]\n", ret, ACOS_TABLE_FILENAME, err); return SWITCH_STATUS_TERM; } return SWITCH_STATUS_TERM; } else switch_log_printf( SWITCH_CHANNEL_LOG, SWITCH_LOG_NOTICE, "Advanced voicemail detection: fast math enabled, arc cosine table " "is [%s]\n", ACOS_TABLE_FILENAME ); #endif SWITCH_ADD_APP(app_interface, "avmd","Beep detection", "Advanced detection of voicemail beeps", avmd_start_function, AVMD_SYNTAX, SAF_NONE); SWITCH_ADD_API(api_interface, "avmd", "Voicemail beep detection", avmd_api_main, AVMD_SYNTAX); switch_console_set_complete("add avmd ::console::list_uuid ::[start:stop"); /* indicate that the module should continue to be loaded */ return SWITCH_STATUS_SUCCESS; } /*! \brief FreeSWITCH application handler function. * This handles calls made from applications such as LUA and the dialplan. * * @author Eric des Courtis * @return Success or failure of the function. */ SWITCH_STANDARD_APP(avmd_start_function) { switch_media_bug_t *bug; switch_status_t status; switch_channel_t *channel; avmd_session_t *avmd_session; switch_media_bug_flag_t flags = 0; if (session == NULL) { switch_log_printf( SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "No FreeSWITCH session assigned!\n" ); return; } channel = switch_core_session_get_channel(session); /* Is this channel already using avmd ? */ bug = (switch_media_bug_t *) switch_channel_get_private(channel, "_avmd_"); /* If it is using avmd */ if (bug != NULL) { /* If we have a stop remove audio bug */ if (strcasecmp(data, "stop") == 0) { switch_channel_set_private(channel, "_avmd_", NULL); switch_core_media_bug_remove(session, &bug); return; } /* We have already started */ switch_log_printf( SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_WARNING, "Cannot run 2 at once on the same channel!\n"); return; } avmd_session = (avmd_session_t *)switch_core_session_alloc( session, sizeof(avmd_session_t)); init_avmd_session_data(avmd_session, session); #ifdef AVMD_INBOUND_CHANNEL flags |= SMBF_READ_REPLACE; #endif #ifdef AVMD_OUTBOUND_CHANNEL flags |= SMBF_WRITE_REPLACE; #endif switch_assert(flags != 0); status = switch_core_media_bug_add( session, "avmd", NULL, avmd_callback, avmd_session, 0, flags, &bug ); if (status != SWITCH_STATUS_SUCCESS) { switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_ERROR, "Failure hooking to stream\n"); return; } switch_channel_set_private(channel, "_avmd_", bug); } /*! \brief Called when the module shuts down. * * @author Eric des Courtis * @return The success or failure of the function. */ SWITCH_MODULE_SHUTDOWN_FUNCTION(mod_avmd_shutdown) { #ifdef AVMD_FAST_MATH int res; #endif switch_event_free_subclass(AVMD_EVENT_BEEP); #ifdef AVMD_FAST_MATH res = destroy_fast_acosf(); if (res != 0) { switch (res) { case -1: switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed unmap arc cosine table\n"); break; case -2: switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed closing arc cosine table\n"); break; default: break; } } #endif switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_NOTICE, "Advanced voicemail detection disabled\n"); return SWITCH_STATUS_SUCCESS; } /*! \brief FreeSWITCH API handler function. * This function handles API calls such as the ones * from mod_event_socket and in some cases * scripts such as LUA scripts. * * @author Eric des Courtis * @return The success or failure of the function. */ SWITCH_STANDARD_API(avmd_api_main) { switch_core_session_t *fs_session = NULL; switch_media_bug_t *bug; avmd_session_t *avmd_session; switch_channel_t *channel; switch_status_t status; int argc; char *argv[AVMD_PARAMS]; char *ccmd = NULL; char *uuid; char *command; switch_core_media_flag_t flags = 0; /* No command? Display usage */ if (zstr(cmd)) { stream->write_function(stream, "-ERR, bad command!\n" "-USAGE: %s\n\n", AVMD_SYNTAX); return SWITCH_STATUS_SUCCESS; } /* Duplicated contents of original string */ ccmd = strdup(cmd); /* Separate the arguments */ argc = switch_separate_string(ccmd, ' ', argv, AVMD_PARAMS); /* If we don't have the expected number of parameters * display usage */ if (argc != AVMD_PARAMS) { stream->write_function(stream, "-ERR, avmd takes [%u] parameters!\n" "-USAGE: %s\n\n", AVMD_PARAMS, AVMD_SYNTAX); goto end; } uuid = argv[0]; command = argv[1]; /* using uuid locate a reference to the FreeSWITCH session */ fs_session = switch_core_session_locate(uuid); /* If the session was not found exit */ if (fs_session == NULL) { stream->write_function(stream, "-ERR, no FreeSWITCH session for uuid [%s]!" "\n-USAGE: %s\n\n", uuid, AVMD_SYNTAX); goto end; } /* Get current channel of the session to tag the session * This indicates that our module is present * At this moment this cannot return NULL, it will either * succeed or assert failed, but we make ourself secure anyway */ channel = switch_core_session_get_channel(fs_session); if (channel == NULL) { stream->write_function(stream, "-ERR, no channel for FreeSWITCH session [%s]!" "\nPlease report this to the developers\n\n", uuid); goto end; } #ifdef AVMD_OUTBOUND_CHANNEL if (SWITCH_CALL_DIRECTION_OUTBOUND != switch_channel_direction(channel)) { stream->write_function(stream, "-ERR, channel for FreeSWITCH session [%s]" "\nis not outbound\n\n", uuid); switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(fs_session), SWITCH_LOG_WARNING, "Channel [%s] is not outbound!\n", switch_channel_get_name(channel)); } else { flags |= SMBF_READ_REPLACE; } #endif #ifdef AVMD_INBOUND_CHANNEL if (SWITCH_CALL_DIRECTION_INBOUND != switch_channel_direction(channel)) { stream->write_function(stream, "-ERR, channel for FreeSWITCH session [%s]" "\nis not inbound.\n\n", uuid); switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(fs_session), SWITCH_LOG_WARNING, "Channel [%s] is not inbound!\n", switch_channel_get_name(channel)); } else { flags |= SMBF_WRITE_REPLACE; } #endif if(flags == 0) { stream->write_function(stream, "-ERR, can't set direction for channel [%s]\n" " for FreeSWITCH session [%s]. Please check avmd configuration\n\n", switch_channel_get_name(channel), uuid); switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(fs_session), SWITCH_LOG_ERROR, "Can't set direction for channel [%s]\n", switch_channel_get_name(channel)); goto end; } #ifdef AVMD_OUTBOUND_CHANNEL if (switch_channel_test_flag(channel, CF_MEDIA_SET) == 0) { stream->write_function(stream, "-ERR, channel [%s] for FreeSWITCH session [%s]" "\nhas no read codec assigned yet. Please try again\n\n", switch_channel_get_name(channel), uuid); switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(fs_session), SWITCH_LOG_ERROR, "Failed to start session. Channel [%s] has no codec assigned yet." " Please try again\n", switch_channel_get_name(channel)); goto end; } #endif /* Is this channel already set? */ bug = (switch_media_bug_t *) switch_channel_get_private(channel, "_avmd_"); /* If yes */ if (bug != NULL) { /* If we have a stop remove audio bug */ if (strcasecmp(command, "stop") == 0) { switch_channel_set_private(channel, "_avmd_", NULL); switch_core_media_bug_remove(fs_session, &bug); switch_safe_free(ccmd); stream->write_function(stream, "+OK, [%s] stopped\n", uuid); goto end; } /* We have already started */ switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(fs_session), SWITCH_LOG_WARNING, "Cannot run 2 at once on the same channel!\n"); goto end; } /* If we don't see the expected start exit */ if (strcasecmp(command, "start") != 0) { stream->write_function(stream, "-ERR, did you mean\n" "api avmd %s start ?\n-USAGE: %s\n\n", uuid, AVMD_SYNTAX); goto end; } /* Allocate memory attached to this FreeSWITCH session for * use in the callback routine and to store state information */ avmd_session = (avmd_session_t *) switch_core_session_alloc( fs_session, sizeof(avmd_session_t)); init_avmd_session_data(avmd_session, fs_session); /* Add a media bug that allows me to intercept the * reading leg of the audio stream */ status = switch_core_media_bug_add( fs_session, "avmd", NULL, avmd_callback, avmd_session, 0, flags, &bug ); /* If adding a media bug fails exit */ if (status != SWITCH_STATUS_SUCCESS) { switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(fs_session), SWITCH_LOG_ERROR, "Failed to add media bug!\n"); stream->write_function(stream, "-ERR, [%s] failed to add media bug!\n\n", uuid); goto end; } /* Set the vmd tag to detect an existing vmd media bug */ switch_channel_set_private(channel, "_avmd_", bug); /* OK */ switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(fs_session), SWITCH_LOG_INFO, "Avmd session on channel [%s] started\n", switch_channel_get_name(channel)); stream->write_function(stream, "+OK, start\n\n"); end: if (fs_session) { switch_core_session_rwunlock(fs_session); } switch_safe_free(ccmd); return SWITCH_STATUS_SUCCESS; } /*! \brief Process one frame of data with avmd algorithm. * @author Eric des Courtis * @par Modifications: Piotr Gregor * @param session An avmd session. * @param frame An audio frame. */ static void avmd_process(avmd_session_t *session, switch_frame_t *frame) { switch_event_t *event; switch_status_t status; switch_event_t *event_copy; switch_channel_t *channel; circ_buffer_t *b; size_t pos; double omega; #ifdef AVMD_DEBUG double f; #endif double v; double sma_digital_freq; uint32_t sine_len_i; char buf[AVMD_CHAR_BUF_LEN]; int sample_to_skip_n = AVMD_SAMLPE_TO_SKIP_N; size_t sample_n = 0; b = &session->b; /* If beep has already been detected skip the CPU heavy stuff */ if (session->state.beep_state == BEEP_DETECTED) return; /* Precompute values used heavily in the inner loop */ sine_len_i = SINE_LEN(session->rate); //sine_len = (double)sine_len_i; //beep_len_i = BEEP_LEN(session->rate); channel = switch_core_session_get_channel(session->session); /* Insert frame of 16 bit samples into buffer */ INSERT_INT16_FRAME(b, (int16_t *)(frame->data), frame->samples); session->sample_count += frame->samples; /* INNER LOOP -- OPTIMIZATION TARGET */ pos = session->pos; while (sample_n < (frame->samples - P)) { /*for (pos = session->pos; pos < (GET_CURRENT_POS(b) - P); pos++) { */ if ((sample_n % sine_len_i) == 0) { /* Get a desa2 frequency estimate every sine len */ omega = avmd_desa2_tweaked(b, pos + sample_n); if (omega < -0.999999 || omega > 0.999999) { #ifdef AVMD_DEBUG switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session->session), SWITCH_LOG_DEBUG, "<<< AVMD RESET >>>\n"); #endif v = 99999.0; #ifdef AVMD_REQUIRE_CONTINUOUS_STREAK RESET_SMA_BUFFER(&session->sma_b); RESET_SMA_BUFFER(&session->sqa_b); session->samples_streak = SAMPLES_CONSECUTIVE_STREAK; sample_to_skip_n = AVMD_SAMLPE_TO_SKIP_N; #endif } else { if (isnan(omega)) { #ifdef AVMD_DEBUG switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session->session), SWITCH_LOG_DEBUG, "<<< AVMD, SKIP NaN >>>\n"); #endif sample_to_skip_n = AVMD_SAMLPE_TO_SKIP_N; goto loop_continue; } if (session->sma_b.pos > 0 && (fabs(omega - session->sma_b.data[session->sma_b.pos - 1]) < 0.00000001)) { #ifdef AVMD_DEBUG switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session->session), SWITCH_LOG_DEBUG, "<<< AVMD, SKIP >>>\n"); #endif goto loop_continue; } #ifdef AVMD_DEBUG switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session->session), SWITCH_LOG_DEBUG, "<<< AVMD omega [%f] >>>\n", omega); #endif if (sample_to_skip_n > 0) { sample_to_skip_n--; goto loop_continue; } /* saturate */ if (omega < -0.9999) omega = -0.9999; if (omega > 0.9999) omega = 0.9999; /* append */ APPEND_SMA_VAL(&session->sma_b, omega); APPEND_SMA_VAL(&session->sqa_b, omega * omega); #ifdef AVMD_REQUIRE_CONTINUOUS_STREAK if (session->samples_streak > 0) --session->samples_streak; #endif /* calculate variance (biased estimator) */ v = session->sqa_b.sma - (session->sma_b.sma * session->sma_b.sma); #ifdef AVMD_DEBUG #ifdef AVMD_FAST_MATH f = 0.5 * (double) fast_acosf((float)omega); sma_digital_freq = 0.5 * (double) fast_acosf((float)session->sma_b.sma); #else f = 0.5 * acos(omega); sma_digital_freq = 0.5 * acos(session->sma_b.sma); #endif /* AVMD_FAST_MATH */ #ifdef AVMD_REQUIRE_CONTINUOUS_STREAK switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session->session), SWITCH_LOG_DEBUG, "<<< AVMD v[%.10f]\tomega[%f]\tf[%f] [%f]Hz\t\tsma[%f][%f]Hz\t\tsqa[%f]\t" "streak[%zu] pos[%zu] sample_n[%zu] lpos[%zu] s[%zu]>>>\n", v, omega, f, TO_HZ(session->rate, f), session->sma_b.sma, TO_HZ(session->rate, sma_digital_freq), session->sqa_b.sma, session->samples_streak, session->sma_b.pos, sample_n, session->sma_b.lpos, pos); #else switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session->session), SWITCH_LOG_DEBUG, "<<< AVMD v[%.10f]\tomega[%f]\tf[%f] [%f]Hz\t\tsma[%f][%f]Hz\t\tsqa[%f]\tpos[%zu]" " sample_n[%zu] lpos[%zu] s[%zu]>>>\n", v, omega, f, TO_HZ(session->rate, f), session->sma_b.sma, TO_HZ(session->rate, sma_digital_freq), session->sqa_b.sma, session->sma_b.pos, sample_n, session->sma_b.lpos, pos); #endif /* AVMD_REQUIRE_CONTINUOUS_STREAK */ #endif /* AVMD_DEBUG */ } /* DECISION */ /* If variance is less than threshold * and we have at least two estimates * then we have detection */ #ifdef AVMD_REQUIRE_CONTINUOUS_STREAK if (v < VARIANCE_THRESHOLD && (session->sma_b.lpos > 1) && (session->samples_streak == 0)) { #else if (v < VARIANCE_THRESHOLD && (session->sma_b.lpos > 1)) { #endif #ifdef AVMD_FAST_MATH sma_digital_freq = 0.5 * (double) fast_acosf((float)session->sma_b.sma); #else sma_digital_freq = 0.5 * acos(session->sma_b.sma); #endif /* AVMD_FAST_MATH */ snprintf(buf, AVMD_CHAR_BUF_LEN, "%f", TO_HZ(session->rate, sma_digital_freq)); switch_channel_set_variable_printf(channel, "avmd_total_time", "[%d]", (int)(switch_micro_time_now() - session->start_time) / 1000); switch_channel_execute_on(channel, "execute_on_avmd_beep"); /* Throw an event to FreeSWITCH */ status = switch_event_create_subclass(&event, SWITCH_EVENT_CUSTOM, AVMD_EVENT_BEEP); if (status != SWITCH_STATUS_SUCCESS) return; switch_event_add_header_string(event, SWITCH_STACK_BOTTOM, "Beep-Status", "stop"); switch_event_add_header_string(event, SWITCH_STACK_BOTTOM, "Unique-ID", switch_core_session_get_uuid(session->session)); switch_event_add_header_string(event, SWITCH_STACK_BOTTOM, "call-command", "avmd"); switch_event_add_header_string(event, SWITCH_STACK_BOTTOM, "frequency", buf); snprintf(buf, AVMD_CHAR_BUF_LEN, "%f", v); switch_event_add_header_string(event, SWITCH_STACK_BOTTOM, "variance", buf); if ((switch_event_dup(&event_copy, event)) != SWITCH_STATUS_SUCCESS) return; switch_core_session_queue_event(session->session, &event); switch_event_fire(&event_copy); #ifdef AVMD_REPORT_STATUS switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session->session), SWITCH_LOG_INFO, "<<< AVMD - Beep Detected: f = [%f], variance = [%f] >>>\n", TO_HZ(session->rate, sma_digital_freq), v); #endif switch_channel_set_variable(channel, "avmd_detect", "TRUE"); RESET_SMA_BUFFER(&session->sma_b); RESET_SMA_BUFFER(&session->sqa_b); session->state.beep_state = BEEP_DETECTED; goto done; } } loop_continue: ++sample_n; } done: session->pos += sample_n; session->pos &= b->mask; return; } /* For Emacs: * Local Variables: * mode:c * indent-tabs-mode:t * tab-width:4 * c-basic-offset:4 * End: * For VIM: * vim:set softtabstop=4 shiftwidth=4 tabstop=4 noet: */