aubuf: better support for different put/get ptime

By default the ptime for writing frames to the aubuf is 20ms. If e.g. module pulse_async is used the ptime for reading dynamically changes and lies around 5ms. - Compute ptime for get/put separately, and consider channel number. - Computed jitter was too low. Reset ts0 and tr0 only if a frame is missing. - Support wish size values that are not a multiple of written frames, if read frames are smaller. This avoids underruns at the beginning of a stream. - Remove the +1 byte for max_sz. This makes no sense and no difference.
baresip · Jun 17, 2022 · 23b910b · 23b910b
1 parent ec60419
commit 23b910b
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Showing 6 changed files with 73 additions and 51 deletions.
diff --git a/docs/aubuf/ajb.plot b/docs/aubuf/ajb.plot
@@ -57,7 +57,7 @@
 # Choose your preferred gnuplot terminal or use e.g. evince to view the
 # ajb.eps!
 
-#set terminal x11
+#set terminal qt persist
 set terminal postscript eps size 15,10 enhanced color
 set output 'ajb.eps'
 #set terminal png size 1280,480

diff --git a/docs/aubuf/config b/docs/aubuf/config
@@ -1,9 +1,9 @@
 #audio_path		/usr/local/share/baresip
-audio_player		pulse,
-audio_source		pulse,
-audio_alert		pulse,
+audio_player		pulse_async,
+audio_source		pulse_async,
+audio_alert		pulse_async,
 audio_level		no
-audio_buffer   20-250
+audio_buffer   30-250
 audio_buffer_mode	adaptive
 audio_silence		0.0
 

diff --git a/docs/aubuf/generate_plots.sh b/docs/aubuf/generate_plots.sh
@@ -16,7 +16,7 @@ function init_jitter () {
 
 function enable_jitter() {
     echo "ENABLE JITTER ..."
-    sudo tc qdisc add dev ifb1 root netem delay 200ms 100ms
+    sudo tc qdisc add dev ifb1 root netem delay 0ms 150ms
 }
 
 
@@ -47,11 +47,11 @@ i=1
 for ptime in 20 10 5 15 30 40; do
 
     sed -e "s/ptime=[0-9]*/ptime=$ptime/" -i accounts
-    for buf in $ptime $(( 2*ptime )) $(( 3*ptime )) $(( 4*ptime )) $(( 6*ptime )); do
+    for buf in $(( ptime + ptime/2 )) $(( ptime )) $(( 2*ptime )) $(( 4*ptime )) $(( 6*ptime )); do
         echo "########### ptime $ptime buffer $buf ###############"
 
         sed -e "s/audio_buffer\s*[0-9]*\-.*/audio_buffer   $buf-250/" -i config
-        baresip -f . > /tmp/b.log 2>&1 &
+        baresip -v -f . > /tmp/b.log 2>&1 &
         sleep 1
         echo "/dial $target" | nc -N localhost 5555
 

diff --git a/src/aubuf/ajb.c b/src/aubuf/ajb.c
@@ -34,8 +34,9 @@ struct ajb {
 	int32_t jitter;      /**< Jitter in [us]                  */
 	mtx_t *lock;
 
-	uint64_t ts0;        /**< previous timestamp              */
-	uint64_t tr0;        /**< previous time of arrival        */
+	uint64_t ts;         /**< previous timestamp              */
+	uint64_t ts0;        /**< reference timestamp             */
+	uint64_t tr0;        /**< reference time of arrival       */
 	uint64_t tr00;       /**< arrival of first packet         */
 #if DEBUG_LEVEL >= 6
 	struct {
@@ -51,7 +52,6 @@ struct ajb {
 
 	enum ajb_state as;   /**< computed jitter buffer state    */
 
-	uint32_t ptime;      /**< Packet time [us]                */
 	int32_t avbuftime;   /**< average buffered time [us]      */
 	bool started;        /**< Started flag                    */
 	uint32_t bufmin;     /**< Minimum buffer time [us]        */
@@ -170,6 +170,7 @@ void ajb_reset(struct ajb *ajb)
 		return;
 
 	mtx_lock(ajb->lock);
+	ajb->ts  = 0;
 	ajb->ts0 = 0;
 	ajb->tr0 = 0;
 
@@ -194,23 +195,23 @@ void ajb_calc(struct ajb *ajb, const struct auframe *af, size_t cur_sz)
 	int32_t d;                         /**< Time shift in [us]           */
 	int32_t da;                        /**< Absolut time shift in [us]   */
 	int32_t s;                         /**< EMA coefficient              */
-	int64_t ts;                        /**< Time stamp                   */
+	uint64_t ts;                       /**< Time stamp                   */
+	uint64_t ds;                       /**< Time stamp duration          */
+	uint32_t ptime;                    /**< Packet time [us]             */
 	size_t sz;
 
-
 	if (!ajb || !af || !af->srate)
 		return;
 
 	mtx_lock(ajb->lock);
 	sz = aufmt_sample_size(af->fmt);
-	ts = (int64_t) af->timestamp;
+	ts = af->timestamp;
 	tr = tmr_jiffies_usec();
 	if (!ajb->ts0)
 		goto out;
 
-	d = (int32_t) ( ((int64_t) tr - (int64_t) ajb->tr0) -
-			(ts - (int64_t) ajb->ts0) );
-
+	ds = ts - ajb->ts0;
+	d = (int32_t) (int64_t) ( (tr - ajb->tr0) - ds );
 	da = abs(d);
 
 	buftime = (uint32_t) (cur_sz * 1000 /
@@ -230,9 +231,6 @@ void ajb_calc(struct ajb *ajb, const struct auframe *af, size_t cur_sz)
 		ajb->started = true;
 	}
 
-	if (!ajb->ptime)
-		goto out;
-
 	s = da > ajb->jitter ? JITTER_UP_SPEED : 1;
 
 	ajb->jitter += (da - ajb->jitter) * s / JITTER_EMA_COEFF;
@@ -242,10 +240,15 @@ void ajb_calc(struct ajb *ajb, const struct auframe *af, size_t cur_sz)
 	bufmin = (uint32_t) ajb->jitter * BUFTIME_LO / 100;
 	bufmax = (uint32_t) ajb->jitter * BUFTIME_HI / 100;
 
-	bufmin = MAX(bufmin, ajb->ptime * 2 / 3);
-	bufmax = MAX(bufmax, bufmin + 7 * ajb->ptime / 6);
+	ptime = (uint32_t) (af->sampc * AUDIO_TIMEBASE / (af->srate * af->ch));
+	bufmin = MAX(bufmin, ptime * 2 / 3);
+	bufmax = MAX(bufmax, bufmin + 7 * ptime / 6);
 	ajb->bufmin = bufmin;
 
+	/* reset time base if a frame is missing */
+	if (ts - ajb->ts > ptime)
+		ajb->ts0 = 0;
+
 	if ((uint32_t) ajb->avbuftime < bufmin)
 		ajb->as = AJB_LOW;
 	else if ((uint32_t) ajb->avbuftime > bufmax)
@@ -261,8 +264,11 @@ void ajb_calc(struct ajb *ajb, const struct auframe *af, size_t cur_sz)
 	plot_ajb(ajb, tr / 1000);
 #endif
 out:
-	ajb->ts0 = ts;
-	ajb->tr0 = tr;
+	ajb->ts = ts;
+	if (!ajb->ts0) {
+		ajb->ts0 = ts;
+		ajb->tr0 = tr;
+	}
 	mtx_unlock(ajb->lock);
 }
 
@@ -273,6 +279,7 @@ void ajb_set_ts0(struct ajb *ajb, uint64_t timestamp)
 		return;
 
 	mtx_lock(ajb->lock);
+	ajb->ts  = timestamp;
 	ajb->ts0 = timestamp;
 	ajb->tr0 = tmr_jiffies_usec();
 	mtx_unlock(ajb->lock);
@@ -282,6 +289,7 @@ void ajb_set_ts0(struct ajb *ajb, uint64_t timestamp)
 enum ajb_state ajb_get(struct ajb *ajb, struct auframe *af)
 {
 	enum ajb_state as = AJB_GOOD;
+	uint32_t ptime;      /**< Packet time [us]                */
 
 	if (!ajb || !af || !af->srate || !af->sampc)
 		return AJB_GOOD;
@@ -290,7 +298,7 @@ enum ajb_state ajb_get(struct ajb *ajb, struct auframe *af)
 	ajb->af = *af;
 
 	/* ptime in [us] */
-	ajb->ptime = (uint32_t) (af->sampc * 1000 * 1000 / af->srate);
+	ptime = (uint32_t) (af->sampc * AUDIO_TIMEBASE / (af->srate * af->ch));
 	if (!ajb->avbuftime)
 		goto out;
 
@@ -301,7 +309,7 @@ enum ajb_state ajb_get(struct ajb *ajb, struct auframe *af)
 	as = ajb->as;
 	if (as == AJB_HIGH) {
 		/* early adjustment of avbuftime */
-		ajb->avbuftime -= ajb->ptime;
+		ajb->avbuftime -= ptime;
 		ajb->as = AJB_GOOD;
 #if DEBUG_LEVEL >= 6
 		ajb->plot.as = AJB_HIGH;
@@ -311,7 +319,7 @@ enum ajb_state ajb_get(struct ajb *ajb, struct auframe *af)
 	}
 	else if (as == AJB_LOW) {
 		/* early adjustment */
-		ajb->avbuftime += ajb->ptime;
+		ajb->avbuftime += ptime;
 		ajb->as = AJB_GOOD;
 #if DEBUG_LEVEL >= 6
 		ajb->plot.as = AJB_LOW;

diff --git a/src/aubuf/ajb.h b/src/aubuf/ajb.h
@@ -4,6 +4,7 @@
  * Copyright (C) 2022 Commend.com - c.spielberger@commend.com
  */
 
+#define AUDIO_TIMEBASE 1000000U
 
 enum ajb_state {
 	AJB_GOOD = 0,

diff --git a/src/aubuf/aubuf.c b/src/aubuf/aubuf.c
@@ -13,7 +13,6 @@
 
 
 #define AUBUF_DEBUG 0
-#define AUDIO_TIMEBASE 1000000U
 
 
 /** Locked audio-buffer with almost zero-copy */
@@ -23,7 +22,8 @@ struct aubuf {
 	size_t wish_sz;
 	size_t cur_sz;
 	size_t max_sz;
-	bool filling;
+	size_t fill_sz;         /**< To fill size                            */
+	uint32_t pkt_sz;        /**< Packet size                             */
 	bool started;
 	uint64_t ts;
 
@@ -130,8 +130,8 @@ int aubuf_alloc(struct aubuf **abp, size_t min_sz, size_t max_sz)
 		goto out;
 
 	ab->wish_sz = min_sz;
-	ab->max_sz = max_sz;
-	ab->filling = true;
+	ab->max_sz  = max_sz;
+	ab->fill_sz = min_sz;
 
  out:
 	if (err)
@@ -216,6 +216,7 @@ int aubuf_append_auframe(struct aubuf *ab, struct mbuf *mb,
 {
 	struct frame *f;
 	size_t max_sz;
+	size_t sz;
 
 	if (!ab || !mb)
 		return EINVAL;
@@ -228,12 +229,17 @@ int aubuf_append_auframe(struct aubuf *ab, struct mbuf *mb,
 	if (af)
 		f->af = *af;
 
+	sz = mbuf_get_left(mb);
+
 	mtx_lock(ab->lock);
+	ab->pkt_sz = sz;
+	if (ab->fill_sz >= ab->pkt_sz)
+		ab->fill_sz -= ab->pkt_sz;
 
 	list_insert_sorted(&ab->afl, frame_less_equal, NULL, &f->le, f);
-	ab->cur_sz += mbuf_get_left(mb);
+	ab->cur_sz += sz;
 
-	max_sz = ab->started ? ab->max_sz : ab->wish_sz + 1;
+	max_sz = ab->started ? ab->max_sz : ab->wish_sz;
 	if (ab->max_sz && ab->cur_sz > max_sz) {
 #if AUBUF_DEBUG
 		if (ab->started) {
@@ -244,16 +250,12 @@ int aubuf_append_auframe(struct aubuf *ab, struct mbuf *mb,
 #endif
 		f = list_ledata(ab->afl.head);
 		if (f) {
-			ab->cur_sz -= mbuf_get_left(f->mb);
+			ab->cur_sz -= sz;
 			mem_deref(f);
 		}
 	}
 
-	if (ab->filling && ab->cur_sz >= ab->wish_sz)
-		ab->filling = false;
-
 	mtx_unlock(ab->lock);
-
 	return 0;
 }
 
@@ -294,7 +296,7 @@ int aubuf_write_auframe(struct aubuf *ab, const struct auframe *af)
 
 	mtx_lock(ab->lock);
 	mem_deref(mb);
-	ajb = !ab->filling && ab->ajb;
+	ajb = !ab->fill_sz && ab->ajb;
 	mtx_unlock(ab->lock);
 
 	if (ajb)
@@ -320,6 +322,7 @@ void aubuf_read_auframe(struct aubuf *ab, struct auframe *af)
 	if (!ab || !af)
 		return;
 
+	sz = auframe_size(af);
 	if (!ab->ajb && ab->mode == AUBUF_ADAPTIVE)
 		ab->ajb = ajb_alloc(ab->silence);
 
@@ -333,27 +336,28 @@ void aubuf_read_auframe(struct aubuf *ab, struct auframe *af)
 		goto out;
 	}
 
-	sz = auframe_size(af);
-	if (ab->cur_sz < (ab->filling ? ab->wish_sz : sz)) {
+	if (ab->fill_sz || ab->cur_sz < sz) {
 #if AUBUF_DEBUG
-		if (!ab->filling) {
+		if (!ab->fill_sz) {
 			++ab->stats.ur;
-			(void)re_printf("aubuf: %p underrun (cur=%zu)\n",
-					ab, ab->cur_sz);
+			(void)re_printf("aubuf: %p underrun "
+					"(cur=%zu, sz=%zu)\n",
+					ab, ab->cur_sz, sz);
+			fflush(stdout);
 			plot_underrun(ab->ajb);
 		}
 #endif
-		if (!ab->filling)
+		if (!ab->fill_sz)
 			ajb_set_ts0(ab->ajb, 0);
 
-		filling = ab->filling;
-		ab->filling = true;
+		filling = ab->fill_sz > 0;
 		memset(af->sampv, 0, sz);
 		if (filling)
 			goto out;
+		else
+			ab->fill_sz = ab->wish_sz;
 	}
 
-	ab->started = true;
 	read_auframe(ab, af);
 	if (as == AJB_HIGH) {
 #if AUBUF_DEBUG
@@ -364,6 +368,15 @@ void aubuf_read_auframe(struct aubuf *ab, struct auframe *af)
 	}
 
  out:
+
+	if (ab->fill_sz && ab->fill_sz < ab->pkt_sz) {
+		if (ab->fill_sz >= sz)
+			ab->fill_sz -= sz;
+		else
+			ab->fill_sz = 0;
+	}
+
+	ab->started = true;
 	mtx_unlock(ab->lock);
 }
 
@@ -426,7 +439,7 @@ void aubuf_flush(struct aubuf *ab)
 	mtx_lock(ab->lock);
 
 	list_flush(&ab->afl);
-	ab->filling = true;
+	ab->fill_sz = ab->wish_sz;
 	ab->cur_sz  = 0;
 	ab->ts      = 0;
 
@@ -451,8 +464,8 @@ int aubuf_debug(struct re_printf *pf, const struct aubuf *ab)
 		return 0;
 
 	mtx_lock(ab->lock);
-	err = re_hprintf(pf, "wish_sz=%zu cur_sz=%zu filling=%d",
-			 ab->wish_sz, ab->cur_sz, ab->filling);
+	err = re_hprintf(pf, "wish_sz=%zu cur_sz=%zu fill_sz=%zu",
+			 ab->wish_sz, ab->cur_sz, ab->fill_sz);
 
 #if AUBUF_DEBUG
 	err |= re_hprintf(pf, " [overrun=%zu underrun=%zu]",