From 5a9b602c9e19afe3ee9df02ce67af95f92309309 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Olivier=20Cr=C3=AAte?= <olivier.crete@collabora.com>
Date: Tue, 18 Jun 2019 13:45:15 -0400
Subject: [PATCH] rtph264pay: Report latency when in maximal aggregation mode

---
 gst/rtp/gstrtph264pay.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
 gst/rtp/gstrtph264pay.h |  3 +++
 2 files changed, 48 insertions(+)

diff --git a/gst/rtp/gstrtph264pay.c b/gst/rtp/gstrtph264pay.c
index 0ccd3dc..17f94ee 100644
--- a/gst/rtp/gstrtph264pay.c
+++ b/gst/rtp/gstrtph264pay.c
@@ -125,6 +125,8 @@ static gboolean gst_rtp_h264_pay_sink_event (GstRTPBasePayload * payload,
     GstEvent * event);
 static GstStateChangeReturn gst_rtp_h264_pay_change_state (GstElement *
     element, GstStateChange transition);
+static gboolean gst_rtp_h264_pay_src_query (GstPad * pad, GstObject * parent,
+    GstQuery * query);
 
 static void gst_rtp_h264_pay_reset_bundle (GstRtpH264Pay * rtph264pay);
 
@@ -214,6 +216,9 @@ gst_rtp_h264_pay_init (GstRtpH264Pay * rtph264pay)
   rtph264pay->discont = FALSE;
 
   rtph264pay->adapter = gst_adapter_new ();
+
+  gst_pad_set_query_function (GST_RTP_BASE_PAYLOAD_SRCPAD (rtph264pay),
+      gst_rtp_h264_pay_src_query);
 }
 
 static void
@@ -398,6 +403,42 @@ done:
   return caps;
 }
 
+static gboolean
+gst_rtp_h264_pay_src_query (GstPad * pad, GstObject * parent, GstQuery * query)
+{
+  GstRtpH264Pay *rtph264pay = GST_RTP_H264_PAY (parent);
+
+  if (GST_QUERY_TYPE (query) == GST_QUERY_LATENCY) {
+    gboolean retval;
+    gboolean live;
+    GstClockTime min_latency, max_latency;
+
+    retval = gst_pad_query_default (pad, parent, query);
+    if (!retval)
+      return retval;
+
+    if (rtph264pay->stream_format == GST_H264_STREAM_FORMAT_UNKNOWN ||
+        rtph264pay->alignment == GST_H264_ALIGNMENT_UNKNOWN)
+      return FALSE;
+
+    gst_query_parse_latency (query, &live, &min_latency, &max_latency);
+
+    if (rtph264pay->aggregate_mode == GST_RTP_H264_AGGREGATE_MAX_STAP &&
+        rtph264pay->alignment != GST_H264_ALIGNMENT_AU && rtph264pay->fps_num) {
+      GstClockTime one_frame = gst_util_uint64_scale_int (GST_SECOND,
+          rtph264pay->fps_denum, rtph264pay->fps_num);
+
+      min_latency += one_frame;
+      max_latency += one_frame;
+      gst_query_set_latency (query, live, min_latency, max_latency);
+    }
+    return TRUE;
+  }
+
+  return gst_pad_query_default (pad, parent, query);
+}
+
+
 /* take the currently configured SPS and PPS lists and set them on the caps as
  * sprop-parameter-sets */
 static gboolean
@@ -504,6 +545,10 @@ gst_rtp_h264_pay_setcaps (GstRTPBasePayload * basepayload, GstCaps * caps)
       rtph264pay->stream_format = GST_H264_STREAM_FORMAT_BYTESTREAM;
   }
 
+  if (!gst_structure_get_fraction (str, "framerate", &rtph264pay->fps_num,
+          &rtph264pay->fps_denum))
+    rtph264pay->fps_num = rtph264pay->fps_denum = 0;
+
   /* packetized AVC video has a codec_data */
   if ((value = gst_structure_get_value (str, "codec_data"))) {
     guint num_sps, num_pps;
diff --git a/gst/rtp/gstrtph264pay.h b/gst/rtp/gstrtph264pay.h
index e6cce4c..879394b 100644
--- a/gst/rtp/gstrtph264pay.h
+++ b/gst/rtp/gstrtph264pay.h
@@ -82,6 +82,9 @@ struct _GstRtpH264Pay
   gboolean send_spspps;
   GstClockTime last_spspps;
 
+  gint fps_num;
+  gint fps_denum;
+
   /* TRUE if the next NALU processed should have the DELTA_UNIT flag */
   gboolean delta_unit;
   /* TRUE if the next NALU processed should have the DISCONT flag */
-- 
2.7.4