From: Piotr Gregor <piotrek.gregor@gmail.com>
Date: Fri, 19 Aug 2016 18:41:19 +0000 (+0100)
Subject: FS-9447: [mod_avmd] increase default value of samples to skip
X-Git-Tag: v1.6.10~1^2~17^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fb065a148aca5925dd13893c80bdb60c7f459cc3;p=thirdparty%2Ffreeswitch.git

FS-9447: [mod_avmd] increase default value of samples to skip

Increase value of samples to skip at the beginning of new frame.
This increases the robustness against false detections observed
on German voicemail from Switzerland (see wav audio attached
to case FS-9447).
---

diff --git a/src/mod/applications/mod_avmd/conf/autoload_configs/avmd.conf.xml b/src/mod/applications/mod_avmd/conf/autoload_configs/avmd.conf.xml
index 039658cf8d..2366195621 100644
--- a/src/mod/applications/mod_avmd/conf/autoload_configs/avmd.conf.xml
+++ b/src/mod/applications/mod_avmd/conf/autoload_configs/avmd.conf.xml
@@ -8,12 +8,14 @@
 
         <!-- Global settings -->
 
-            <!-- define/undefine this to enable/disable printing of avmd
+            <!-- define/undefine this to enable/disable logging of avmd
                  intermediate computations to log -->
             <param name="debug" value="0"/>
 
-            <!-- define/undef this to enable/disable reporting of beep
-                 detection status after session ended -->
+            <!-- define/undef this to enable/disable verbose logging (and reporting to the console)
+                 of detection status and other diagnostics like parameters avmd session has been started with,
+                 change of configuration parameters, beep detection status after session ended
+                 (stop event is fired independently of this setting and beep status included there) -->
             <param name="report_status" value="1"/>
 
             <!-- define/undefine this to enable/disable faster computation
@@ -33,12 +35,15 @@
             <param name="require_continuous_streak" value="1"/>
 
             <!-- required number of consecutive elements in the SMA buffer
-                 without reset -->
+                 without reset. This parameter helps to avoid false beeps, bigger this value is
+                smaller the probability of getting false detection -->
             <param name="sample_n_continuous_streak" value="15"/>
 
             <!-- define number of samples to skip starting from the beginning
-                 of the frame and after reset -->
-            <param name="sample_n_to_skip" value="6"/>
+                 of the frame and/or after reset  has happened. This serves the purpose of skipping first few
+                estimations on each frame, as these estimations may be inaccurate. This parameter also helps
+                to give more robust detections when it's value is increased (up to scertain limit of about 60). -->
+            <param name="sample_n_to_skip" value="15"/>
 
             <!-- define/undefine this to enable/disable simplified estimation
                  of frequency based on approximation of sin(x) with (x)