1 files changed, 26 insertions, 8 deletions

diff --git a/src/lib/ndpi_analyze.c b/src/lib/ndpi_analyze.c
index 176f4eeef..1f72cb978 100644
--- a/src/lib/ndpi_analyze.c
+++ b/src/lib/ndpi_analyze.c
@@ -38,18 +38,14 @@
 /* ********************************************************************************* */
 
 void ndpi_init_data_analysis(struct ndpi_analyze_struct *ret, u_int16_t _max_series_len) {
-  u_int32_t len;
-
   memset(ret, 0, sizeof(*ret));
 
   if(_max_series_len > MAX_SERIES_LEN) _max_series_len = MAX_SERIES_LEN;
   ret->num_values_array_len = _max_series_len;
 
   if(ret->num_values_array_len > 0) {
-    len = sizeof(u_int64_t) * ret->num_values_array_len;
-    if((ret->values = ndpi_malloc(len)) != NULL)
-      memset(ret->values, 0, len);
-    else
+    if((ret->values = (u_int64_t *)ndpi_calloc(ret->num_values_array_len,
+					       sizeof(u_int64_t))) == NULL)
       ret->num_values_array_len = 0;
   }
 }
@@ -116,6 +112,12 @@ void ndpi_data_add_value(struct ndpi_analyze_struct *s, const u_int64_t value) {
   if(!s)
     return;
 
+  if(s->num_data_entries > 0) {
+    u_int64_t last = ndpi_data_last(s);
+
+    s->jitter_total += (last > value) ? (last - value) : (value - last);
+  }
+
   if(s->sum_total == 0)
     s->min_val = s->max_val = value;
   else {
@@ -205,6 +207,15 @@ float ndpi_data_mean(struct ndpi_analyze_struct *s) {
 
 /* ********************************************************************************* */
 
+float ndpi_data_jitter(struct ndpi_analyze_struct *s) {
+  if(!s || s->num_data_entries < 2)
+    return(0);
+  else
+    return((float)s->jitter_total / (float)(s->num_data_entries - 1));
+}
+
+/* ********************************************************************************* */
+
 /* Compute the average only on the sliding window */
 float ndpi_data_window_average(struct ndpi_analyze_struct *s) {
   if(s && s->num_values_array_len) {
@@ -1356,9 +1367,16 @@ int ndpi_ses_add_value(struct ndpi_ses_struct *ses, const double _value, double
 
   if(ses->num_values == 0)
     *forecast = value;
-  else
+  else {
+#if 1
+    /* "Classic" formula */
+    *forecast = (ses->params.alpha * value) + ((1 - ses->params.alpha) * ses->last_forecast);
+#else
+    /* Alternative formula */
     *forecast = (ses->params.alpha * (ses->last_value - ses->last_forecast)) + ses->last_forecast;
-
+#endif
+  }
+  
   error  = value - *forecast;
   sq_error =  error * error;
   ses->sum_square_error += sq_error, ses->prev_error.sum_square_error += sq_error;