Changeset 3115 for pjproject/trunk/pjsip-apps/src/samples/aectest.c

Timestamp:

Mar 3, 2010 2:47:35 PM (14 years ago)

Author:

nanang

Message:

Ticket #1042, minor updates related to AEC:

• Added requirement of AEC minimal latency between reference and echo in aectest sample app.
• Modified AEC latency in sound port to 3/4 of playback latency.
• Few cleaned up echo_common.c: unused vars, a bit stricter latency check (to be at least as much as PTIME).

File:

• pjproject/trunk/pjsip-apps/src/samples/aectest.c (modified) (5 diffs)

pjproject/trunk/pjsip-apps/src/samples/aectest.c

@@ -56 +56 @@
 "\n"
 " options:\n"
-"  -d  The delay between playback and capture in ms. Default is zero.\n"
+"  -d  The delay between playback and capture in ms, at least 25 ms.\n"
+"      Default is 25 ms. See note below.                            \n"
 "  -l  Set the echo tail length in ms. Default is 200 ms            \n"
 "  -r  Set repeat count (default=1)                                 \n"
 "  -a  Algorithm: 0=default, 1=speex, 3=echo suppress               \n"
-"  -i  Interactive                                                  \n";
+"  -i  Interactive                                                  \n"
+"\n"
+" Note that for the AEC internal buffering mechanism, it is required\n"
+" that the echoed signal (in REC.WAV) is delayed from the           \n"
+" corresponding reference signal (in PLAY.WAV) at least as much as  \n"
+" frame time + PJMEDIA_WSOLA_DELAY_MSEC. In this application, frame \n"
+" time is 20 ms and default PJMEDIA_WSOLA_DELAY_MSEC is 5 ms, hence \n"
+" 25 ms delay is the minimum value.                                 \n";
 
 /* 
@@ -92 +100 @@
     pjmedia_frame play_frame, rec_frame;
     unsigned opt = 0;
-    unsigned latency_ms = 0;
+    unsigned latency_ms = 25;
     unsigned tail_ms = TAIL_LENGTH;
     pj_timestamp t0, t1;
@@ -102 +110 @@
         case 'd':
             latency_ms = atoi(pj_optarg);
+            if (latency_ms < 25) {
+                puts("Invalid delay");
+                puts(desc);
+            }
             break;
         case 'l':
@@ -128 +140 @@
             repeat = atoi(pj_optarg);
             if (repeat < 1) {
-                puts("Invalid algorithm");
+                puts("Invalid repeat count");
                 puts(desc);
                 return 1;
@@ -252 +264 @@
     pj_get_timestamp(&t1);
 
-    i = pjmedia_wav_writer_port_get_pos(wav_out) * 1000 / 
+    i = pjmedia_wav_writer_port_get_pos(wav_out) / sizeof(pj_int16_t) * 1000 / 
         (wav_out->info.clock_rate * wav_out->info.channel_count);
     PJ_LOG(3,(THIS_FILE, "Processed %3d.%03ds audio",