From 10a16a632106a7ffdf7df50df5062497cff6d663 Mon Sep 17 00:00:00 2001
From: Arun Raghavan <arun@arunraghavan.net>
Date: Sat, 24 Sep 2016 23:22:01 +0530
Subject: [PATCH] rtpsbcpay: Fix timestamping

We were just picking the timestamp of the last buffer pushed into our
adapter before we had enough data to push out.

This fixes things to figure out how large each frame is and what
duration it covers, so we can set both the timestamp and duration
correctly.

Also adds some DISCONT handling.
---
 gst/rtp/gstrtpsbcpay.c | 27 ++++++++++++++++++++++-----
 gst/rtp/gstrtpsbcpay.h |  3 ++-
 2 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/gst/rtp/gstrtpsbcpay.c b/gst/rtp/gstrtpsbcpay.c
index dc3d860742..794a817ed8 100644
--- a/gst/rtp/gstrtpsbcpay.c
+++ b/gst/rtp/gstrtpsbcpay.c
@@ -157,6 +157,8 @@ gst_rtp_sbc_pay_set_caps (GstRTPBasePayload * payload, GstCaps * caps)
       bitpool, channel_mode);
 
   sbcpay->frame_length = frame_len;
+  sbcpay->frame_duration = ((blocks * subbands) * GST_SECOND) / rate;
+  sbcpay->last_timestamp = GST_CLOCK_TIME_NONE;
 
   gst_rtp_base_payload_set_options (payload, "audio", TRUE, "SBC", rate);
 
@@ -214,9 +216,12 @@ gst_rtp_sbc_pay_flush_buffers (GstRtpSBCPay * sbcpay)
       g_quark_from_static_string (GST_META_TAG_AUDIO_STR));
   outbuf = gst_buffer_append (outbuf, paybuf);
 
-  /* FIXME: what about duration? */
-  GST_BUFFER_PTS (outbuf) = sbcpay->timestamp;
-  GST_DEBUG_OBJECT (sbcpay, "Pushing %d bytes", payload_length);
+  GST_BUFFER_PTS (outbuf) = sbcpay->last_timestamp;
+  GST_BUFFER_DURATION (outbuf) = frame_count * sbcpay->frame_duration;
+  GST_DEBUG_OBJECT (sbcpay, "Pushing %d bytes: %" GST_TIME_FORMAT,
+      payload_length, GST_TIME_ARGS (GST_BUFFER_PTS (outbuf)));
+
+  sbcpay->last_timestamp += frame_count * sbcpay->frame_duration;
 
   return gst_rtp_base_payload_push (GST_RTP_BASE_PAYLOAD (sbcpay), outbuf);
 }
@@ -230,7 +235,19 @@ gst_rtp_sbc_pay_handle_buffer (GstRTPBasePayload * payload, GstBuffer * buffer)
   /* FIXME check for negotiation */
 
   sbcpay = GST_RTP_SBC_PAY (payload);
-  sbcpay->timestamp = GST_BUFFER_PTS (buffer);
+
+  if (GST_BUFFER_IS_DISCONT (buffer)) {
+    /* Try to flush whatever's left */
+    gst_rtp_sbc_pay_flush_buffers (sbcpay);
+    /* Drop the rest */
+    gst_adapter_flush (sbcpay->adapter,
+        gst_adapter_available (sbcpay->adapter));
+    /* Reset timestamps */
+    sbcpay->last_timestamp = GST_CLOCK_TIME_NONE;
+  }
+
+  if (sbcpay->last_timestamp == GST_CLOCK_TIME_NONE)
+    sbcpay->last_timestamp = GST_BUFFER_PTS (buffer);
 
   gst_adapter_push (sbcpay->adapter, buffer);
 
@@ -347,7 +364,7 @@ gst_rtp_sbc_pay_init (GstRtpSBCPay * self)
 {
   self->adapter = gst_adapter_new ();
   self->frame_length = 0;
-  self->timestamp = 0;
+  self->last_timestamp = GST_CLOCK_TIME_NONE;
 
   self->min_frames = DEFAULT_MIN_FRAMES;
 }
diff --git a/gst/rtp/gstrtpsbcpay.h b/gst/rtp/gstrtpsbcpay.h
index 42cf02e2d4..76ee66da34 100644
--- a/gst/rtp/gstrtpsbcpay.h
+++ b/gst/rtp/gstrtpsbcpay.h
@@ -46,9 +46,10 @@ struct _GstRtpSBCPay {
 	GstRTPBasePayload base;
 
 	GstAdapter *adapter;
-	GstClockTime timestamp;
+	GstClockTime last_timestamp;
 
 	guint frame_length;
+        GstClockTime frame_duration;
 
 	guint min_frames;
 };