Changeset 3115

Timestamp:

Mar 3, 2010 2:47:35 PM (15 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).

Location:

pjproject/trunk

Files:

• pjmedia/src/pjmedia/echo_common.c (modified) (4 diffs)
• pjmedia/src/pjmedia/sound_port.c (modified) (1 diff)
• pjsip-apps/src/samples/aectest.c (modified) (5 diffs)

pjproject/trunk/pjmedia/src/pjmedia/echo_common.c

@@ -25 +25 @@
 #include <pj/list.h>
 #include <pj/log.h>
+#include <pj/math.h>
 #include <pj/pool.h>
 #include "echo_internal.h"
@@ -47 +48 @@
 
     pj_bool_t        lat_ready;     /* lat_buf has been filled in.          */
-    unsigned         lat_target_cnt;/* Target number of frames in lat_buf   */
-    unsigned         lat_buf_cnt;   /* Actual number of frames in lat_buf   */
     struct frame     lat_buf;       /* Frame queue for delayed playback     */
     struct frame     lat_free;      /* Free frame list.                     */
@@ -145 +144 @@
                                          pjmedia_echo_state **p_echo )
 {
-    unsigned ptime;
+    unsigned ptime, lat_cnt;
     pjmedia_echo_state *ec;
     pj_status_t status;
@@ -195 +194 @@
     /* Create latency buffers */
     ptime = samples_per_frame * 1000 / clock_rate;
-    if (latency_ms == 0) {
+    if (latency_ms > ptime) {
+        /* Normalize latency with delaybuf/WSOLA latency */
+        latency_ms -= PJ_MIN(ptime, PJMEDIA_WSOLA_DELAY_MSEC);
+    }
+    if (latency_ms < ptime) {
         /* Give at least one frame delay to simplify programming */
         latency_ms = ptime;
     }
-    ec->lat_target_cnt = latency_ms / ptime;
-    if (ec->lat_target_cnt != 0) {
-        unsigned i;
-        for (i=0; i < ec->lat_target_cnt; ++i)  {
-            struct frame *frm;
-
-            frm = (struct frame*) pj_pool_alloc(pool, (samples_per_frame<<1) +
-                                                      sizeof(struct frame));
-            pj_list_push_back(&ec->lat_free, frm);
-        }
-    } else {
-        ec->lat_ready = PJ_TRUE;
+    lat_cnt = latency_ms / ptime;
+    while (lat_cnt--)  {
+        struct frame *frm;
+
+        frm = (struct frame*) pj_pool_alloc(pool, (samples_per_frame<<1) +
+                                                  sizeof(struct frame));
+        pj_list_push_back(&ec->lat_free, frm);
     }
 

pjproject/trunk/pjmedia/src/pjmedia/sound_port.c

@@ -564 +564 @@
             //delay_ms = (si.rec_latency + si.play_latency) * 1000 /
             //     snd_port->clock_rate;
-            delay_ms = prm.output_latency_ms;
+            /* Set EC latency to 3/4 of output latency to reduce the
+             * possibility of missing/late reference frame.
+             */
+            delay_ms = prm.output_latency_ms * 3/4;
             status = pjmedia_echo_create2(pool, snd_port->clock_rate, 
                                           snd_port->channel_count,

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",