Changeset 2208

Timestamp:

Aug 13, 2008 1:50:19 PM (16 years ago)

Author:

bennylp

Message:

More ticket #590: handle the case when mic level is set too high causing echo to be mistakenly treated as local user speaking

File:

• pjproject/trunk/pjmedia/src/pjmedia/echo_suppress.c (modified) (8 diffs)

pjproject/trunk/pjmedia/src/pjmedia/echo_suppress.c

@@ -382 +382 @@
 
 /* Set state */
-static void echo_supp_set_state(echo_supp *ec, enum talk_state state)
-{
+static void echo_supp_set_state(echo_supp *ec, enum talk_state state, 
+                                unsigned level)
+{
+    PJ_UNUSED_ARG(level);
+
     if (state != ec->talk_state) {
-        TRACE_((THIS_FILE, "[%03d.%03d] %s --> %s", 
+        TRACE_((THIS_FILE, "[%03d.%03d] %s --> %s, level=%u", 
                            (ec->update_cnt * SEGMENT_PTIME / 1000), 
                            ((ec->update_cnt * SEGMENT_PTIME) % 1000),
                            state_names[ec->talk_state],
-                           state_names[state]));
+                           state_names[state], level));
         ec->talk_state = state;
     }
@@ -466 +469 @@
         ulaw = pjmedia_linear2ulaw(sum_play_level/ec->templ_cnt) ^ 0xFF;
         if (ulaw < MIN_SIGNAL_ULAW) {
-            echo_supp_set_state(ec, ST_REM_SILENT);
+            echo_supp_set_state(ec, ST_REM_SILENT, ulaw);
             return;
         }
@@ -472 +475 @@
         /* Bail out if local user is talking */
         if (sum_rec_level >= sum_play_level) {
-            echo_supp_set_state(ec, ST_LOCAL_TALK);
+            echo_supp_set_state(ec, ST_LOCAL_TALK, ulaw);
             return;
         }
 
+#if 0
+        // disabled: not a good idea if mic throws out loud echo
         /* Also bail out if we suspect there's a doubletalk */
         ulaw = pjmedia_linear2ulaw(sum_rec_level/ec->templ_cnt) ^ 0xFF;
         if (ulaw > MIN_SIGNAL_ULAW) {
-            echo_supp_set_state(ec, ST_DOUBLETALK);
+            echo_supp_set_state(ec, ST_DOUBLETALK, ulaw);
             return;
         }
+#endif
 
         /* Calculate correlation and save to temporary array */
@@ -493 +499 @@
 
     /* We seem to have good signal, we can update the EC state */
-    echo_supp_set_state(ec, ST_REM_TALK);
+    echo_supp_set_state(ec, ST_REM_TALK, MIN_SIGNAL_ULAW);
 
     /* Accummulate the correlation value to the history and at the same
@@ -646 +652 @@
                  */
                 factor = 1.0;
-                echo_supp_set_state(ec, ST_LOCAL_TALK);
-            } else {
+                echo_supp_set_state(ec, ST_LOCAL_TALK, rec_level);
+            } else if (rec_level >= play_level) {
                 /* Seems that both are talking. Scale the mic signal
                  * down a little bit to reduce echo, while allowing both
@@ -653 +659 @@
                  */
                 factor = (float)(ec->avg_factor[ec->tail_index] * 2);
-                echo_supp_set_state(ec, ST_DOUBLETALK);
+                echo_supp_set_state(ec, ST_DOUBLETALK, rec_level);
+            } else {
+                /* Speaker is active, but we've picked up large signal in
+                 * the microphone. Assume that this is an echo, so bring 
+                 * the level down to minimum too.
+                 */
+                factor = ec->min_factor[ec->tail_index] / 2;
+                echo_supp_set_state(ec, ST_REM_TALK, play_level);
             }
         } else {
@@ -662 +675 @@
                  */
                 factor = ec->avg_factor[ec->tail_index] * 3 / 2;
-                echo_supp_set_state(ec, ST_REM_SILENT);
+                echo_supp_set_state(ec, ST_REM_SILENT, rec_level);
             } else {
                 /* Mic is idle, but there's something playing in speaker.
@@ -668 +681 @@
                  */
                 factor = ec->min_factor[ec->tail_index] / 2;
-                echo_supp_set_state(ec, ST_REM_TALK);
+                echo_supp_set_state(ec, ST_REM_TALK, play_level);
             }
         }