From 7c402d5866a3fcfeba2768e702a50899d7491b27 Mon Sep 17 00:00:00 2001
From: Zaheer Abbas Merali <zaheerabbas@merali.org>
Date: Fri, 21 May 2010 13:14:04 +0100
Subject: [PATCH] matroskamux: add streamheaders

---
 gst/matroska/ebml-write.c   | 52 +++++++++++++++++++++++++++++++++++
 gst/matroska/ebml-write.h   |  8 ++++++
 gst/matroska/matroska-mux.c | 66 +++++++++++++++++++++++++++++++--------------
 3 files changed, 106 insertions(+), 20 deletions(-)

diff --git a/gst/matroska/ebml-write.c b/gst/matroska/ebml-write.c
index 2b1e2fd..b31472d 100644
--- a/gst/matroska/ebml-write.c
+++ b/gst/matroska/ebml-write.c
@@ -62,6 +62,9 @@ gst_ebml_write_init (GstEbmlWrite * ebml, GstEbmlWriteClass * klass)
   ebml->pos = 0;
 
   ebml->cache = NULL;
+  ebml->streamheader = NULL;
+  ebml->streamheader_pos = 0;
+  ebml->writing_streamheader = FALSE;
 }
 
 static void
@@ -76,6 +79,11 @@ gst_ebml_write_finalize (GObject * object)
     ebml->cache = NULL;
   }
 
+  if (ebml->streamheader) {
+    gst_byte_writer_free (ebml->streamheader);
+    ebml->streamheader = NULL;
+  }
+
   GST_CALL_PARENT (G_OBJECT_CLASS, finalize, (object));
 }
 
@@ -142,6 +150,33 @@ gst_ebml_last_write_result (GstEbmlWrite * ebml)
 }
 
 
+void
+gst_ebml_start_streamheader (GstEbmlWrite * ebml)
+{
+  g_return_if_fail (ebml->streamheader == NULL);
+
+  GST_DEBUG ("Starting streamheader at %" G_GUINT64_FORMAT, ebml->pos);
+  ebml->streamheader = gst_byte_writer_new_with_size (1000, FALSE);
+  ebml->streamheader_pos = ebml->pos;
+  ebml->writing_streamheader = TRUE;
+}
+
+GstBuffer *
+gst_ebml_stop_streamheader (GstEbmlWrite * ebml)
+{
+  GstBuffer *buffer;
+
+  if (!ebml->streamheader)
+    return NULL;
+
+  buffer = gst_byte_writer_free_and_get_buffer (ebml->streamheader);
+  ebml->streamheader = NULL;
+  GST_DEBUG ("Streamheader was size %d", GST_BUFFER_SIZE (buffer));
+
+  ebml->writing_streamheader = FALSE;
+  return buffer;
+}
+
 /**
  * gst_ebml_write_set_cache:
  * @ebml: a #GstEbmlWrite.
@@ -336,6 +371,10 @@ gst_ebml_write_element_push (GstEbmlWrite * ebml, GstBuffer * buf)
   ebml->pos += data_size;
 
   /* if there's no cache, then don't push it! */
+  if (ebml->writing_streamheader) {
+    gst_byte_writer_put_data (ebml->streamheader, GST_BUFFER_DATA (buf),
+        data_size);
+  }
   if (ebml->cache) {
     gst_byte_writer_put_data (ebml->cache, GST_BUFFER_DATA (buf), data_size);
     gst_buffer_unref (buf);
@@ -371,6 +410,19 @@ gst_ebml_write_seek (GstEbmlWrite * ebml, guint64 pos)
 {
   GstEvent *event;
 
+  if (ebml->writing_streamheader) {
+    GST_DEBUG ("wanting to seek to pos %" G_GUINT64_FORMAT, pos);
+    if (pos >= ebml->streamheader_pos &&
+        pos <= ebml->streamheader_pos + ebml->streamheader->parent.size) {
+      gst_byte_writer_set_pos (ebml->streamheader,
+          pos - ebml->streamheader_pos);
+      GST_DEBUG ("seeked in streamheader to position %" G_GUINT64_FORMAT,
+          pos - ebml->streamheader_pos);
+    } else {
+      GST_WARNING
+          ("we are writing streamheader still and seek is out of bounds");
+    }
+  }
   /* Cache seeking. A bit dangerous, we assume the client writer
    * knows what he's doing... */
   if (ebml->cache) {
diff --git a/gst/matroska/ebml-write.h b/gst/matroska/ebml-write.h
index 26e9d9e..72ac2e1 100644
--- a/gst/matroska/ebml-write.h
+++ b/gst/matroska/ebml-write.h
@@ -55,6 +55,10 @@ typedef struct _GstEbmlWrite {
   GstFlowReturn last_write_result;
 
   gboolean need_newsegment;
+
+  gboolean writing_streamheader;
+  GstByteWriter *streamheader;
+  guint64 streamheader_pos;
 } GstEbmlWrite;
 
 typedef struct _GstEbmlWriteClass {
@@ -68,6 +72,10 @@ void    gst_ebml_write_reset         (GstEbmlWrite *ebml);
 
 GstFlowReturn gst_ebml_last_write_result (GstEbmlWrite *ebml);
 
+/* Used to create streamheaders */
+void    gst_ebml_start_streamheader  (GstEbmlWrite *ebml);
+GstBuffer*    gst_ebml_stop_streamheader   (GstEbmlWrite *ebml);
+
 /*
  * Caching means that we do not push one buffer for
  * each element, but fill this one until a flush.
diff --git a/gst/matroska/matroska-mux.c b/gst/matroska/matroska-mux.c
index 9a70121..1a15ee5 100644
--- a/gst/matroska/matroska-mux.c
+++ b/gst/matroska/matroska-mux.c
@@ -2005,11 +2005,13 @@ gst_matroska_mux_start (GstMatroskaMux * mux)
   GstClockTime duration = 0;
   guint32 segment_uid[4];
   GTimeVal time = { 0, 0 };
+  GstBuffer *streamheader_buffer;
 
   /* we start with a EBML header */
   doctype = mux->doctype;
   GST_INFO_OBJECT (ebml, "DocType: %s, Version: %d",
       doctype, mux->doctype_version);
+  gst_ebml_start_streamheader (ebml);
   gst_ebml_write_header (ebml, doctype, mux->doctype_version);
 
   /* the rest of the header is cached */
@@ -2044,30 +2046,31 @@ gst_matroska_mux_start (GstMatroskaMux * mux)
   gst_ebml_write_uint (ebml, GST_MATROSKA_ID_TIMECODESCALE, mux->time_scale);
   mux->duration_pos = ebml->pos;
   /* get duration */
-  for (collected = mux->collect->data; collected;
-      collected = g_slist_next (collected)) {
-    GstMatroskaPad *collect_pad;
-    GstFormat format = GST_FORMAT_TIME;
-    GstPad *thepad;
-    gint64 trackduration;
-
-    collect_pad = (GstMatroskaPad *) collected->data;
-    thepad = collect_pad->collect.pad;
+  if (!mux->is_live) {
+    for (collected = mux->collect->data; collected;
+        collected = g_slist_next (collected)) {
+      GstMatroskaPad *collect_pad;
+      GstFormat format = GST_FORMAT_TIME;
+      GstPad *thepad;
+      gint64 trackduration;
 
-    /* Query the total length of the track. */
-    GST_DEBUG_OBJECT (thepad, "querying peer duration");
-    if (gst_pad_query_peer_duration (thepad, &format, &trackduration)) {
-      GST_DEBUG_OBJECT (thepad, "duration: %" GST_TIME_FORMAT,
-          GST_TIME_ARGS (trackduration));
-      if (trackduration != GST_CLOCK_TIME_NONE && trackduration > duration) {
-        duration = (GstClockTime) trackduration;
+      collect_pad = (GstMatroskaPad *) collected->data;
+      thepad = collect_pad->collect.pad;
+
+      /* Query the total length of the track. */
+      GST_DEBUG_OBJECT (thepad, "querying peer duration");
+      if (gst_pad_query_peer_duration (thepad, &format, &trackduration)) {
+        GST_DEBUG_OBJECT (thepad, "duration: %" GST_TIME_FORMAT,
+            GST_TIME_ARGS (trackduration));
+        if (trackduration != GST_CLOCK_TIME_NONE && trackduration > duration) {
+          duration = (GstClockTime) trackduration;
+        }
       }
     }
+    gst_ebml_write_float (ebml, GST_MATROSKA_ID_DURATION,
+        gst_guint64_to_gdouble (duration) /
+        gst_guint64_to_gdouble (mux->time_scale));
   }
-  gst_ebml_write_float (ebml, GST_MATROSKA_ID_DURATION,
-      gst_guint64_to_gdouble (duration) /
-      gst_guint64_to_gdouble (mux->time_scale));
-
   gst_ebml_write_utf8 (ebml, GST_MATROSKA_ID_MUXINGAPP,
       "GStreamer plugin version " PACKAGE_VERSION);
   if (mux->writing_app && mux->writing_app[0]) {
@@ -2101,6 +2104,29 @@ gst_matroska_mux_start (GstMatroskaMux * mux)
 
   /* lastly, flush the cache */
   gst_ebml_write_flush_cache (ebml);
+  streamheader_buffer = gst_ebml_stop_streamheader (ebml);
+  /* lets set the pad caps, which is how the buffer caps is set currently :( */
+  {
+    GstCaps *caps;
+    GstStructure *s;
+    GValue streamheader = { 0 };
+    GValue bufval = { 0 };
+    if (!strcmp (mux->doctype, GST_MATROSKA_DOCTYPE_WEBM)) {
+      caps = gst_caps_from_string ("video/webm");
+    } else {
+      caps = gst_caps_from_string ("video/x-matroska");
+    }
+    s = gst_caps_get_structure (caps, 0);
+    g_value_init (&streamheader, GST_TYPE_ARRAY);
+    g_value_init (&bufval, GST_TYPE_BUFFER);
+    gst_value_set_buffer (&bufval, streamheader_buffer);
+    gst_value_array_append_value (&streamheader, &bufval);
+    g_value_unset (&bufval);
+    gst_structure_set_value (s, "streamheader", &streamheader);
+    g_value_unset (&streamheader);
+    gst_pad_set_caps (mux->srcpad, caps);
+    gst_caps_unref (caps);
+  }
 }
 
 static void
-- 
2.7.4