From bugtracker: "fix totalAnalysisTime to handle periods of no channel activity"

(closes issue #9256)
Reported by: cmaj
Patches:
      amd-dont-wait-too-long-for-frames-take3.diff.txt uploaded by cmaj (license 111)
Tested by: cmaj, skygreg, ZX81, rjain

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@101649 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/apps/app_amd.c b/apps/app_amd.c
index e5dee1efc528fa7c8341846ff153e12ffe95be44..52f474048105eb10bcad638588b7b4e7b6c1f643 100644 (file)
--- a/apps/app_amd.c
+++ b/apps/app_amd.c
@@ -86,19 +86,22 @@ static int dfltBetweenWordsSilence  = 50;
 static int dfltMaximumNumberOfWords = 3;
 static int dfltSilenceThreshold     = 256;
 
+/* Set to the lowest ms value provided in amd.conf or application parameters */
+static int dfltMaxWaitTimeForFrame  = 50;
+
 static void isAnsweringMachine(struct ast_channel *chan, void *data)
 {
        int res = 0;
        struct ast_frame *f = NULL;
        struct ast_dsp *silenceDetector = NULL;
-       int dspsilence = 0, readFormat, framelength;
+       int dspsilence = 0, readFormat, framelength = 0;
        int inInitialSilence = 1;
        int inGreeting = 0;
        int voiceDuration = 0;
        int silenceDuration = 0;
        int iTotalTime = 0;
        int iWordsCount = 0;
-       int currentState = STATE_IN_SILENCE;
+       int currentState = STATE_IN_WORD;
        int previousState = STATE_IN_SILENCE;
        int consecutiveVoiceDuration = 0;
        char amdCause[256] = "", amdStatus[256] = "";
@@ -116,6 +119,7 @@ static void isAnsweringMachine(struct ast_channel *chan, void *data)
        int betweenWordsSilence  = dfltBetweenWordsSilence;
        int maximumNumberOfWords = dfltMaximumNumberOfWords;
        int silenceThreshold     = dfltSilenceThreshold;
+       int maxWaitTimeForFrame  = dfltMaxWaitTimeForFrame;
 
        AST_DECLARE_APP_ARGS(args,
                             AST_APP_ARG(argInitialSilence);
@@ -154,6 +158,20 @@ static void isAnsweringMachine(struct ast_channel *chan, void *data)
        } else if (option_debug)
                ast_log(LOG_DEBUG, "AMD using the default parameters.\n");
 
+       /* Find lowest ms value, that will be max wait time for a frame */
+       if (maxWaitTimeForFrame > initialSilence)
+               maxWaitTimeForFrame = initialSilence;
+       if (maxWaitTimeForFrame > greeting)
+               maxWaitTimeForFrame = greeting;
+       if (maxWaitTimeForFrame > afterGreetingSilence)
+               maxWaitTimeForFrame = afterGreetingSilence;
+       if (maxWaitTimeForFrame > totalAnalysisTime)
+               maxWaitTimeForFrame = totalAnalysisTime;
+       if (maxWaitTimeForFrame > minimumWordLength)
+               maxWaitTimeForFrame = minimumWordLength;
+       if (maxWaitTimeForFrame > betweenWordsSilence)
+               maxWaitTimeForFrame = betweenWordsSilence;
+
        /* Now we're ready to roll! */
        if (option_verbose > 2)
                ast_verbose(VERBOSE_PREFIX_3 "AMD: initialSilence [%d] greeting [%d] afterGreetingSilence [%d] "
@@ -182,7 +200,8 @@ static void isAnsweringMachine(struct ast_channel *chan, void *data)
        ast_dsp_set_threshold(silenceDetector, silenceThreshold);
 
        /* Now we go into a loop waiting for frames from the channel */
-       while ((res = ast_waitfor(chan, totalAnalysisTime)) > -1) {
+       while ((res = ast_waitfor(chan, 2 * maxWaitTimeForFrame)) > -1) {
+
                /* If we fail to read in a frame, that means they hung up */
                if (!(f = ast_read(chan))) {
                        if (option_verbose > 2)
@@ -193,9 +212,13 @@ static void isAnsweringMachine(struct ast_channel *chan, void *data)
                        break;
                }
 
-               if (f->frametype == AST_FRAME_VOICE) {
+               if (f->frametype == AST_FRAME_VOICE || f->frametype == AST_FRAME_NULL || f->frametype == AST_FRAME_CNG) {
                        /* If the total time exceeds the analysis time then give up as we are not too sure */
-                       framelength = (ast_codec_get_samples(f) / DEFAULT_SAMPLES_PER_MS);
+                       if (f->frametype == AST_FRAME_VOICE)
+                               framelength = (ast_codec_get_samples(f) / DEFAULT_SAMPLES_PER_MS);
+                       else
+                               framelength += 2 * maxWaitTimeForFrame;
+
                        iTotalTime += framelength;
                        if (iTotalTime >= totalAnalysisTime) {
                                if (option_verbose > 2) 
@@ -207,9 +230,14 @@ static void isAnsweringMachine(struct ast_channel *chan, void *data)
                        }
 
                        /* Feed the frame of audio into the silence detector and see if we get a result */
-                       dspsilence = 0;
-                       ast_dsp_silence(silenceDetector, f, &dspsilence);
-                       if (dspsilence) {
+                       if (f->frametype != AST_FRAME_VOICE)
+                               dspsilence += 2 * maxWaitTimeForFrame;
+                       else {
+                               dspsilence = 0;
+                               ast_dsp_silence(silenceDetector, f, &dspsilence);
+                       }
+
+                       if (dspsilence > 0) {
                                silenceDuration = dspsilence;
                                
                                if (silenceDuration >= betweenWordsSilence) {
@@ -229,6 +257,7 @@ static void isAnsweringMachine(struct ast_channel *chan, void *data)
                                        ast_frfree(f);
                                        strcpy(amdStatus , "MACHINE");
                                        sprintf(amdCause , "INITIALSILENCE-%d-%d", silenceDuration, initialSilence);
+                                       res = 1;
                                        break;
                                }
                                
@@ -239,6 +268,7 @@ static void isAnsweringMachine(struct ast_channel *chan, void *data)
                                        ast_frfree(f);
                                        strcpy(amdStatus , "HUMAN");
                                        sprintf(amdCause , "HUMAN-%d-%d", silenceDuration, afterGreetingSilence);
+                                       res = 1;
                                        break;
                                }
                                
@@ -262,6 +292,7 @@ static void isAnsweringMachine(struct ast_channel *chan, void *data)
                                        ast_frfree(f);
                                        strcpy(amdStatus , "MACHINE");
                                        sprintf(amdCause , "MAXWORDS-%d-%d", iWordsCount, maximumNumberOfWords);
+                                       res = 1;
                                        break;
                                }
                                
@@ -271,6 +302,7 @@ static void isAnsweringMachine(struct ast_channel *chan, void *data)
                                        ast_frfree(f);
                                        strcpy(amdStatus , "MACHINE");
                                        sprintf(amdCause , "LONGGREETING-%d-%d", voiceDuration, greeting);
+                                       res = 1;
                                        break;
                                }