[Freeswitch-svn] [commit] r10623 - freeswitch/trunk/src/mod/applications/mod_vmd
FreeSWITCH SVN
ericdc at freeswitch.org
Fri Dec 5 09:45:39 PST 2008
Author: ericdc
Date: Fri Dec 5 12:45:37 2008
New Revision: 10623
Log:
Voicemain detection mod initial upload. By Eric des Courtis
Added:
freeswitch/trunk/src/mod/applications/mod_vmd/Makefile
freeswitch/trunk/src/mod/applications/mod_vmd/mod_vmd.cpp
Added: freeswitch/trunk/src/mod/applications/mod_vmd/Makefile
==============================================================================
--- (empty file)
+++ freeswitch/trunk/src/mod/applications/mod_vmd/Makefile Fri Dec 5 12:45:37 2008
@@ -0,0 +1,2 @@
+BASE=../../../..
+include $(BASE)/build/modmake.rules
Added: freeswitch/trunk/src/mod/applications/mod_vmd/mod_vmd.cpp
==============================================================================
--- (empty file)
+++ freeswitch/trunk/src/mod/applications/mod_vmd/mod_vmd.cpp Fri Dec 5 12:45:37 2008
@@ -0,0 +1,726 @@
+/*
+ * FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application
+ * Copyright (C) 2008, Eric des Courtis <eric.des.courtis at benbria.com>
+ *
+ * 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 <eric.des.courtis at benbria.com>
+ * Copyright (C) Benbria. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * Eric des Courtis <eric.des.courtis at benbria.com>
+ *
+ *
+ * mod_vmd.c -- Voicemail Detection Module
+ *
+ * This module detects voicemail beeps at any frequency in O(1) time.
+ *
+ */
+
+#include <switch.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <strings.h>
+#include <string.h>
+#include <math.h>
+
+/* Number of points for beep detection */
+#define POINTS 32
+
+/* Number of valid points required for beep detection */
+#define VALID 22
+
+/* Maximum number of invalid points
+ * to declare beep has stopped */
+#define MAX_CHIRP 22
+
+/* Minimum time for a beep */
+#define MIN_TIME 8000
+
+/* Minimum amplitude of the signal */
+#define MIN_AMPL 0.10
+
+/* Minimum beep frequency */
+#define MIN_FREQ (600)
+
+/* Maximum beep frequency */
+#define MAX_FREQ (1100)
+
+/* PSI function for amplitude calculation*/
+#define PSI(x) (x[1]*x[1]-x[2]*x[0])
+
+/* Sample rate */
+#define F (8000)
+
+/* Conversion of frequency to Hz */
+#define TO_HZ(f) ((F * f) / (2.0 * M_PI))
+
+/* Number of points in discreet energy separation */
+#define P (5)
+
+/* Maximum signed value of int16_t
+ * DEPRECATED */
+#define ADJUST (32768)
+/* Same as above times two
+ * DEPRECATED */
+#define ADJUST_MAX (65536)
+
+/* Signed L16 to relative floating point conversion */
+#define CONVERT_PT(d, i, m) do{ d = ((((double)i + (double)m) / \
+ (double)(2 * m)) - 0.5) * 2.0; } while(0)
+
+/* Discreet energy separation tolerance to error */
+#define TOLERANCE (0.20)
+
+/* Maximum value within tolerance */
+#define TOLERANCE_T(m) (m + (m * TOLERANCE))
+
+/* Minimum value within tolerance */
+#define TOLERANCE_B(m) (m - (m * TOLERANCE))
+
+/* Syntax of the API call */
+#define VMD_SYNTAX "<uuid> <command>"
+
+/* Number of expected parameters in api call */
+#define VMD_PARAMS 2
+
+/* FreeSWITCH CUSTOM event type */
+#define VMD_EVENT_BEEP "vmd::beep"
+
+/* Prototypes */
+SWITCH_MODULE_SHUTDOWN_FUNCTION(mod_vmd_shutdown);
+/* SWITCH_MODULE_RUNTIME_FUNCTION(mod_vmd_runtime); */
+SWITCH_STANDARD_API(vmd_api_main);
+
+SWITCH_MODULE_LOAD_FUNCTION(mod_vmd_load);
+SWITCH_MODULE_DEFINITION(mod_vmd, mod_vmd_load, NULL, NULL);
+SWITCH_STANDARD_APP(vmd_start_function);
+
+/* Type that holds state information about the beep */
+typedef enum vmd_state{
+ BEEP_DETECTED, BEEP_NOT_DETECTED
+} vmd_state_t;
+
+/* Type that holds data for 5 points of discreet energy separation */
+typedef struct vmd_point{
+ double freq;
+ double ampl;
+} vmd_point_t;
+
+/* Type that holds codec information */
+typedef struct vmd_codec_info{
+ int rate;
+ int channels;
+} vmd_codec_info_t;
+
+/* Type that holds session information pertinent to the vmd module */
+typedef struct vmd_session_info{
+ /* State of the session */
+ vmd_state_t state;
+ /* Snapshot of DESA samples */
+ vmd_point_t points[POINTS];
+ /* Internal FreeSWITCH session */
+ switch_core_session_t *session;
+ /* Codec information for the session */
+ vmd_codec_info_t vmd_codec;
+ /* Current position in the snapshot */
+ unsigned int pos;
+ /* Frequency aproximation of a detected beep */
+ double beep_freq;
+ /* A count of how long a distinct beep was detected by
+ * by the discreet energy separation algorithm */
+ switch_size_t timestamp;
+/*
+ int16_t *data;
+ ssize_t data_len;
+*/
+} vmd_session_info_t;
+
+static switch_bool_t process_data(vmd_session_info_t *vmd_info,
+ switch_frame_t *frame);
+static switch_bool_t vmd_callback(switch_media_bug_t *bug,
+ void *user_data, switch_abc_type_t type);
+static double freq_estimator(double *x);
+static double ampl_estimator(double *x);
+static void convert_pts(int16_t *i_pts, double *d_pts, int16_t max);
+static void find_beep(vmd_session_info_t *vmd_info, switch_frame_t *frame);
+static double median(double *m, int n);
+
+/*
+#define PRINT(a) do{ switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, a); }while(0)
+#define PRINT2(a, b) do{ switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, a, b); }while(0)
+*/
+
+static switch_bool_t vmd_callback(switch_media_bug_t *bug,
+ void *user_data, switch_abc_type_t type)
+{
+ vmd_session_info_t *vmd_info;
+ switch_codec_t *read_codec;
+ switch_frame_t *frame;
+
+ vmd_info = (vmd_session_info_t *)user_data;
+ if(vmd_info == NULL) return SWITCH_FALSE;
+
+ switch(type){
+
+ case SWITCH_ABC_TYPE_INIT:
+ read_codec =
+ switch_core_session_get_read_codec(vmd_info->session);
+ vmd_info->vmd_codec.rate =
+ read_codec->implementation->samples_per_second;
+ vmd_info->vmd_codec.channels =
+ read_codec->implementation->number_of_channels;
+ break;
+
+ case SWITCH_ABC_TYPE_CLOSE:
+ case SWITCH_ABC_TYPE_READ:
+ case SWITCH_ABC_TYPE_WRITE:
+ break;
+
+ case SWITCH_ABC_TYPE_READ_REPLACE:
+ frame = switch_core_media_bug_get_read_replace_frame(bug);
+ return process_data(vmd_info, frame);
+
+ case SWITCH_ABC_TYPE_WRITE_REPLACE:
+ break;
+ }
+
+ return SWITCH_TRUE;
+}
+
+static switch_bool_t process_data(vmd_session_info_t *vmd_info,
+ switch_frame_t *frame)
+{
+ int i;
+ unsigned int j;
+ double pts[P];
+ int16_t *data;
+ int16_t max;
+ ssize_t len;
+
+ len = frame->samples * sizeof(int16_t);
+ data = (int16_t *)frame->data;
+
+ for(max = abs(data[0]), i = 1; i < frame->samples; i++){
+ if(abs(data[i]) > max) max = abs(data[i]);
+ }
+
+/*
+ if(vmd_info->data_len != len){
+ vmd_info->data_len = len;
+ if(vmd_info->data != NULL) free(vmd_info->data);
+ vmd_info->data = (int16_t *)malloc(len);
+ if(vmd_info->data == NULL) return SWITCH_FALSE;
+ }
+
+ (void)memcpy(vmd_info->data, data, len);
+ for(i = 2; i < frame->samples; i++){
+ vmd_info->data[i] =
+ 0.0947997 * data[i]
+ -
+ 0.0947997 * data[i - 2]
+ -
+ 1.4083405 * vmd_info->data[i - 1]
+ +
+ 0.8104005 * vmd_info->data[i - 2];
+ }
+*/
+
+ for(i = 0, j = vmd_info->pos; i < frame->samples; j++, j %= POINTS, i += 5){
+/* convert_pts(vmd_info->data + i, pts); */
+ convert_pts(data + i, pts, max);
+ vmd_info->points[j].freq = TO_HZ(freq_estimator(pts));
+ vmd_info->points[j].ampl = ampl_estimator(pts);
+ vmd_info->pos = j % POINTS;
+ find_beep(vmd_info, frame);
+ }
+
+ return SWITCH_TRUE;
+}
+
+static void find_beep(vmd_session_info_t *vmd_info, switch_frame_t *frame)
+{
+ int i;
+ int c;
+ double m[POINTS];
+ double med;
+ unsigned int j = (vmd_info->pos + 1) % POINTS;
+ unsigned int k = j;
+ switch_status_t status;
+ switch_event_t *event;
+ switch_event_t *event_copy;
+
+ switch(vmd_info->state){
+ case BEEP_DETECTED:
+ for(c = 0, i = 0; i < POINTS; j++, j %= POINTS, i++){
+ vmd_info->timestamp++;
+ if(vmd_info->points[j].freq < TOLERANCE_T(vmd_info->beep_freq) &&
+ vmd_info->points[j].freq > TOLERANCE_B(vmd_info->beep_freq)){
+ c++;
+ vmd_info->beep_freq = (vmd_info->beep_freq * 0.95) + (vmd_info->points[j].freq * 0.05);
+ }
+ }
+
+ if(c < (POINTS - MAX_CHIRP)){
+ vmd_info->state = BEEP_NOT_DETECTED;
+ if(vmd_info->timestamp < MIN_TIME) break;
+
+ status = switch_event_create_subclass(&event,
+ SWITCH_EVENT_CUSTOM, VMD_EVENT_BEEP);
+ if(status != SWITCH_STATUS_SUCCESS) return;
+
+ switch_event_add_header_string(
+ event,
+ SWITCH_STACK_BOTTOM,
+ "Beep-Status",
+ "stop"
+ );
+
+ switch_event_add_header(
+ event,
+ SWITCH_STACK_BOTTOM,
+ "Beep-Time",
+ "%d", vmd_info->timestamp / POINTS
+ );
+
+ switch_event_add_header(
+ event,
+ SWITCH_STACK_BOTTOM,
+ "Unique-ID",
+ "%s", switch_core_session_get_uuid(vmd_info->session)
+ );
+
+ switch_event_add_header(
+ event,
+ SWITCH_STACK_BOTTOM,
+ "Frequency",
+ "%6.4lf", vmd_info->beep_freq
+ );
+
+ switch_event_add_header_string(
+ event,
+ SWITCH_STACK_BOTTOM,
+ "call-command",
+ "vmd"
+ );
+
+ status = switch_event_dup(&event_copy, event);
+ if(status != SWITCH_STATUS_SUCCESS) return;
+
+ switch_core_session_queue_event(vmd_info->session, &event);
+ switch_event_fire(&event_copy);
+
+ vmd_info->timestamp = 0;
+ }
+
+ break;
+
+ case BEEP_NOT_DETECTED:
+
+ for(i = 0; i < POINTS; k++, k %= POINTS, i++){
+ m[i] = vmd_info->points[k].freq;
+ if(m[i] == NAN) m[i] = 0.0;
+ }
+
+ med = median(m, POINTS);
+ if(med == NAN){
+ for(i = 0; i < POINTS; i++){
+ if(m[i] != NAN){
+ med = m[i];
+ break;
+ }
+ }
+ }
+
+ for(c = 0, i = 0; i < POINTS; j++, j %= POINTS, i++){
+ if(vmd_info->points[j].freq < TOLERANCE_T(med) &&
+ vmd_info->points[j].freq > TOLERANCE_B(med)){
+ if(vmd_info->points[j].ampl > MIN_AMPL &&
+ vmd_info->points[j].freq > MIN_FREQ &&
+ vmd_info->points[j].freq < MAX_FREQ){
+ c++;
+ }
+ }
+ }
+
+
+ if(c >= VALID){
+ vmd_info->state = BEEP_DETECTED;
+ vmd_info->beep_freq = med;
+ vmd_info->timestamp = 0;
+ }
+
+ break;
+ }
+}
+
+/* Find the median of an array of doubles */
+static double median(double *m, int n)
+{
+ int i;
+ int less;
+ int greater;
+ int equal;
+ double min;
+ double max;
+ double guess;
+ double maxltguess;
+ double mingtguess;
+
+ min = max = m[0] ;
+
+ for (i = 1; i < n; i++) {
+ if(m[i] < min) min = m[i];
+ if(m[i] > max) max = m[i];
+ }
+
+ while(1){
+ guess = ( min + max ) / 2;
+ less = 0;
+ greater = 0;
+ equal = 0;
+ maxltguess = min;
+ mingtguess = max;
+
+ for(i = 0; i < n; i++) {
+ if(m[i] < guess){
+ less++;
+ if(m[i] > maxltguess) maxltguess = m[i];
+ }else if (m[i] > guess) {
+ greater++;
+ if(m[i] < mingtguess) mingtguess = m[i];
+ }else equal++;
+ }
+
+ if (less <= ( n + 1 ) / 2 && greater <= ( n + 1 ) / 2) break;
+ else if (less > greater) max = maxltguess;
+ else min = mingtguess;
+ }
+
+ if(less >= ( n + 1 ) / 2) return maxltguess;
+ else if(less + equal >= ( n + 1 ) / 2) return guess;
+
+ return mingtguess;
+}
+
+/* Convert many points for Signed L16 to relative floating point */
+static void convert_pts(int16_t *i_pts, double *d_pts, int16_t max)
+{
+ int i;
+ for(i = 0; i < P; i++) CONVERT_PT(d_pts[i], i_pts[i], max);
+}
+
+/* Amplitude estimator for DESA-2 */
+double ampl_estimator(double *x)
+{
+ double freq_sq;
+
+ freq_sq = freq_estimator(x);
+ freq_sq *= freq_sq;
+
+ return sqrt( PSI(x) / sin(freq_sq) );
+}
+
+/* The DESA-2 algorithm */
+double freq_estimator(double *x)
+{
+ return 0.5 * acos(
+ (((x[2] * x[2]) - (x[0] * x[4]))
+ -
+ ( (x[1] * x[1]) - (x[0] * x[2]))
+ -
+ ( (x[3] * x[3]) - (x[2] * x[4])))
+ /
+ (2.0 * ((x[2] * x[2]) - (x[1] * x[3])))
+
+ );
+}
+
+
+SWITCH_MODULE_LOAD_FUNCTION(mod_vmd_load)
+{
+ 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);
+
+ switch_log_printf(
+ SWITCH_CHANNEL_LOG,
+ SWITCH_LOG_NOTICE,
+ "Voicemail detection enabled\n"
+ );
+
+ SWITCH_ADD_APP(app_interface, "vmd", "Detect beeps", "Detect voicemail beeps",
+ vmd_start_function, "[start] [stop]", SAF_NONE);
+
+ SWITCH_ADD_API(api_interface, "vmd", "Detected voicemail beeps",
+ vmd_api_main, VMD_SYNTAX);
+
+ /* indicate that the module should continue to be loaded */
+ return SWITCH_STATUS_SUCCESS;
+}
+
+/* Same as api function see it for comments */
+SWITCH_STANDARD_APP(vmd_start_function)
+{
+ switch_media_bug_t *bug;
+ switch_status_t status;
+ switch_channel_t *channel;
+ vmd_session_info_t *vmd_info;
+ int i;
+
+ if(session == NULL) return;
+
+ channel = switch_core_session_get_channel(session);
+
+ /* Is this channel already set? */
+ bug = (switch_media_bug_t *) switch_channel_get_private(channel, "_vmd_");
+ /* If yes */
+ if(bug != NULL){
+ /* If we have a stop remove audio bug */
+ if(strcasecmp(data, "stop") == 0){
+ switch_channel_set_private(channel, "_vmd_", NULL);
+ switch_core_media_bug_remove(session, &bug);
+ return;
+ }
+
+ /* We have already started */
+ switch_log_printf(
+ SWITCH_CHANNEL_LOG,
+ SWITCH_LOG_WARNING,
+ "Cannot run 2 at once on the same channel!\n"
+ );
+
+ return;
+ }
+
+ vmd_info = (vmd_session_info_t *)switch_core_session_alloc(
+ session,
+ sizeof(vmd_session_info_t)
+ );
+
+ vmd_info->state = BEEP_NOT_DETECTED;
+ vmd_info->session = session;
+ vmd_info->pos = 0;
+/*
+ vmd_info->data = NULL;
+ vmd_info->data_len = 0;
+*/
+ for(i = 0; i < POINTS; i++){
+ vmd_info->points[i].freq = 0.0;
+ vmd_info->points[i].ampl = 0.0;
+ }
+
+ status = switch_core_media_bug_add(
+ session,
+ vmd_callback,
+ vmd_info,
+ 0,
+ SMBF_READ_REPLACE,
+ &bug
+ );
+
+ if(status != SWITCH_STATUS_SUCCESS){
+ switch_log_printf(
+ SWITCH_CHANNEL_LOG,
+ SWITCH_LOG_ERROR,
+ "Failure hooking to stream\n"
+ );
+
+ return;
+ }
+
+
+ switch_channel_set_private(channel, "_vmd_", bug);
+
+}
+
+/* Called when the system shuts down */
+SWITCH_MODULE_SHUTDOWN_FUNCTION(mod_vmd_shutdown)
+{
+ switch_log_printf(
+ SWITCH_CHANNEL_LOG,
+ SWITCH_LOG_NOTICE,
+ "Voicemail detection disabled\n"
+ );
+
+ return SWITCH_STATUS_SUCCESS;
+}
+
+SWITCH_STANDARD_API(vmd_api_main)
+{
+ switch_core_session_t *vmd_session;
+ switch_media_bug_t *bug;
+ vmd_session_info_t *vmd_info;
+ switch_channel_t *channel;
+ switch_event_t *event;
+ switch_status_t status;
+ int argc;
+ char *argv[VMD_PARAMS];
+ char *ccmd;
+ char *uuid;
+ char *command;
+ int i;
+
+ /* No command? Display usage */
+ if(cmd == NULL){
+ stream->write_function(stream, "-USAGE: %s\n", VMD_SYNTAX);
+ return SWITCH_STATUS_SUCCESS;
+ }
+
+ /* Duplicated contents of original string */
+ ccmd = strdup(cmd);
+ /* Separate the arguments */
+ argc = switch_separate_string(ccmd, ' ', argv, VMD_PARAMS);
+
+ /* If we don't have the expected number of parameters
+ * display usage */
+ if(argc != VMD_PARAMS){
+ stream->write_function(stream, "-USAGE: %s\n", VMD_SYNTAX);
+ switch_safe_free(ccmd);
+ return SWITCH_STATUS_SUCCESS;
+ }
+
+ uuid = argv[0];
+ command = argv[1];
+
+ /* using uuid locate a reference to the FreeSWITCH session */
+ vmd_session = switch_core_session_locate(uuid);
+
+ /* If the session was not found exit */
+ if(vmd_session == NULL){
+ switch_safe_free(ccmd);
+ stream->write_function(stream, "-USAGE: %s\n", VMD_SYNTAX);
+ return SWITCH_STATUS_FALSE;
+ }
+
+ /* Get current channel of the session to tag the session
+ * This indicates that our module is present */
+ channel = switch_core_session_get_channel(vmd_session);
+
+ /* Is this channel already set? */
+ bug = (switch_media_bug_t *) switch_channel_get_private(channel, "_vmd_");
+ /* If yes */
+ if(bug != NULL){
+ /* If we have a stop remove audio bug */
+ if(strcasecmp(command, "stop") == 0){
+ switch_channel_set_private(channel, "_vmd_", NULL);
+ switch_core_media_bug_remove(vmd_session, &bug);
+ switch_safe_free(ccmd);
+ stream->write_function(stream, "+OK\n");
+ return SWITCH_STATUS_SUCCESS;
+ }
+
+ /* We have already started */
+ switch_log_printf(
+ SWITCH_CHANNEL_LOG,
+ SWITCH_LOG_WARNING,
+ "Cannot run 2 at once on the same channel!\n"
+ );
+
+ switch_safe_free(ccmd);
+ return SWITCH_STATUS_FALSE;
+ }
+
+ /* If we don't see the expected start exit */
+ if(strcasecmp(command, "start") != 0){
+ switch_safe_free(ccmd);
+ stream->write_function(stream, "-USAGE: %s\n", VMD_SYNTAX);
+ return SWITCH_STATUS_FALSE;
+ }
+
+ /* Allocate memory attached to this FreeSWITCH session for
+ * use in the callback routine and to store state information */
+ vmd_info = (vmd_session_info_t *)switch_core_session_alloc(
+ vmd_session,
+ sizeof(vmd_session_info_t)
+ );
+
+ /* Set initial values and states */
+ vmd_info->state = BEEP_NOT_DETECTED;
+ vmd_info->session = vmd_session;
+ vmd_info->pos = 0;
+/*
+ vmd_info->data = NULL;
+ vmd_info->data_len = 0;
+*/
+
+ for(i = 0; i < POINTS; i++){
+ vmd_info->points[i].freq = 0.0;
+ vmd_info->points[i].ampl = 0.0;
+ }
+
+ /* Add a media bug that allows me to intercept the
+ * reading leg of the audio stream */
+ status = switch_core_media_bug_add(
+ vmd_session,
+ vmd_callback,
+ vmd_info,
+ 0,
+ SMBF_READ_REPLACE,
+ &bug
+ );
+
+ /* If adding a media bug fails exit */
+ if(status != SWITCH_STATUS_SUCCESS){
+ switch_log_printf(
+ SWITCH_CHANNEL_LOG,
+ SWITCH_LOG_ERROR,
+ "Failure hooking to stream\n"
+ );
+
+ switch_safe_free(ccmd);
+ return SWITCH_STATUS_FALSE;
+ }
+
+ /* Set the vmd tag to detect an existing vmd media bug */
+ switch_channel_set_private(channel, "_vmd_", bug);
+
+ /* Everything went according to plan! Notify the user */
+ stream->write_function(stream, "+OK\n");
+
+ switch_safe_free(ccmd);
+ return SWITCH_STATUS_SUCCESS;
+}
+
+/*
+ If it exists, this is called in it's own thread
+ when the module-load completes. If it returns anything
+ but SWITCH_STATUS_TERM it will be called again automatically
+*/
+
+/*
+SWITCH_MODULE_RUNTIME_FUNCTION(mod_vmd_runtime)
+{
+ while(looping){
+
+ switch_yield(1000);
+ }
+
+ return SWITCH_STATUS_TERM;
+}
+*/
+
+/* 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 expandtab:
+ */
+
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