From b4d8c04f08dce9f720fd4df3237d4f9986f98c43 Mon Sep 17 00:00:00 2001
From: Mathieu Duponchelle <mathieu.duponchelle@opencreed.com>
Date: Mon, 2 Mar 2015 13:53:03 +0100
Subject: [PATCH] adaptivedemux: [API]: get_presentation_offset virtual method.

Asks the subclass for a potential time offset to apply to each
separate stream, in dash streams can have "presentation time offsets",
which can be different for each stream.

https://bugzilla.gnome.org/show_bug.cgi?id=745455
---
 gst-libs/gst/adaptivedemux/gstadaptivedemux.c | 21 +++++++++++++++++++
 gst-libs/gst/adaptivedemux/gstadaptivedemux.h | 12 +++++++++++
 2 files changed, 33 insertions(+)

diff --git a/gst-libs/gst/adaptivedemux/gstadaptivedemux.c b/gst-libs/gst/adaptivedemux/gstadaptivedemux.c
index 97eee51b98..e06c14bc37 100644
--- a/gst-libs/gst/adaptivedemux/gstadaptivedemux.c
+++ b/gst-libs/gst/adaptivedemux/gstadaptivedemux.c
@@ -701,6 +701,19 @@ gst_adaptive_demux_expose_stream (GstAdaptiveDemux * demux,
   return gst_element_add_pad (GST_ELEMENT_CAST (demux), pad);
 }
 
+static GstClockTime
+gst_adaptive_demux_stream_get_presentation_offset (GstAdaptiveDemux * demux,
+    GstAdaptiveDemuxStream * stream)
+{
+  GstAdaptiveDemuxClass *klass;
+
+  klass = GST_ADAPTIVE_DEMUX_GET_CLASS (demux);
+
+  g_return_val_if_fail (klass->get_presentation_offset, FALSE);
+
+  return klass->get_presentation_offset (demux, stream);
+}
+
 static gboolean
 gst_adaptive_demux_expose_streams (GstAdaptiveDemux * demux,
     gboolean first_segment)
@@ -741,8 +754,12 @@ gst_adaptive_demux_expose_streams (GstAdaptiveDemux * demux,
         min_pts;
   for (iter = demux->streams; iter; iter = g_list_next (iter)) {
     GstAdaptiveDemuxStream *stream = iter->data;
+    GstClockTime offset;
 
+    offset = gst_adaptive_demux_stream_get_presentation_offset (demux, stream);
     stream->segment = demux->segment;
+    stream->segment.start = stream->segment.position =
+        stream->fragment.timestamp + offset;
     stream->pending_segment = gst_event_new_segment (&stream->segment);
   }
 
@@ -1347,6 +1364,8 @@ gst_adaptive_demux_stream_push_buffer (GstAdaptiveDemuxStream * stream,
   GstAdaptiveDemux *demux = stream->demux;
   GstFlowReturn ret = GST_FLOW_OK;
   gboolean discont = FALSE;
+  GstClockTime offset =
+      gst_adaptive_demux_stream_get_presentation_offset (demux, stream);
 
   if (stream->first_fragment_buffer) {
     if (demux->segment.rate < 0)
@@ -1375,6 +1394,8 @@ gst_adaptive_demux_stream_push_buffer (GstAdaptiveDemuxStream * stream,
 
   stream->first_fragment_buffer = FALSE;
 
+  if (GST_BUFFER_PTS (buffer) != GST_CLOCK_TIME_NONE)
+    GST_BUFFER_PTS (buffer) += offset;
   GST_BUFFER_DURATION (buffer) = GST_CLOCK_TIME_NONE;
   GST_BUFFER_DTS (buffer) = GST_CLOCK_TIME_NONE;
 
diff --git a/gst-libs/gst/adaptivedemux/gstadaptivedemux.h b/gst-libs/gst/adaptivedemux/gstadaptivedemux.h
index 6169af7577..36e20ef7ea 100644
--- a/gst-libs/gst/adaptivedemux/gstadaptivedemux.h
+++ b/gst-libs/gst/adaptivedemux/gstadaptivedemux.h
@@ -377,6 +377,18 @@ struct _GstAdaptiveDemuxClass
    * Return: %TRUE if successful
    */
   gboolean (*get_live_seek_range) (GstAdaptiveDemux * demux, gint64 * start, gint64 * stop);
+
+  /**
+   * get_presentation_offset:
+   * @demux: #GstAdaptiveDemux
+   * @stream: #GstAdaptiveDemuxStream
+   *
+   * Gets the delay to apply to @stream.
+   *
+   * Return: a #GstClockTime representing the (positive) time offset to apply to
+   * @stream.
+   */
+  GstClockTime (*get_presentation_offset) (GstAdaptiveDemux *demux, GstAdaptiveDemuxStream *stream);
 };
 
 GType    gst_adaptive_demux_get_type (void);