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diff --git a/gst/videomixer/videomixer2.c b/gst/videomixer/videomixer2.c
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+++ b/gst/videomixer/videomixer2.c
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+/* Generic video mixer plugin
+ * Copyright (C) 2004, 2008 Wim Taymans <wim@fluendo.com>
+ * Copyright (C) 2010 Sebastian Dröge <sebastian.droege@collabora.co.uk>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+/**
+ * SECTION:element-videomixer2
+ *
+ * Videomixer2 can accept AYUV, ARGB and BGRA video streams. For each of the requested
+ * sink pads it will compare the incoming geometry and framerate to define the
+ * output parameters. Indeed output video frames will have the geometry of the
+ * biggest incoming video stream and the framerate of the fastest incoming one.
+ *
+ * All sink pads must be either AYUV, ARGB or BGRA, but a mixture of them is not 
+ * supported. The src pad will have the same colorspace as the sinks. 
+ * No colorspace conversion is done. 
+ * 
+ * Individual parameters for each input stream can be configured on the
+ * #GstVideoMixer2Pad.
+ *
+ * At this stage, videomixer2 is considered UNSTABLE. The API provided in the
+ * properties may yet change in the near future. When videomixer2 is stable,
+ * it will replace #videomixer
+ *
+ * <refsect2>
+ * <title>Sample pipelines</title>
+ * |[
+ * gst-launch-0.10 \
+ *   videotestsrc pattern=1 ! \
+ *   video/x-raw-yuv,format=\(fourcc\)AYUV,framerate=\(fraction\)10/1,width=100,height=100 ! \
+ *   videobox border-alpha=0 top=-70 bottom=-70 right=-220 ! \
+ *   videomixer2 name=mix sink_0::alpha=0.7 sink_1::alpha=0.5 ! \
+ *   ffmpegcolorspace ! xvimagesink \
+ *   videotestsrc ! \
+ *   video/x-raw-yuv,format=\(fourcc\)AYUV,framerate=\(fraction\)5/1,width=320,height=240 ! mix.
+ * ]| A pipeline to demonstrate videomixer used together with videobox.
+ * This should show a 320x240 pixels video test source with some transparency
+ * showing the background checker pattern. Another video test source with just
+ * the snow pattern of 100x100 pixels is overlayed on top of the first one on
+ * the left vertically centered with a small transparency showing the first
+ * video test source behind and the checker pattern under it. Note that the
+ * framerate of the output video is 10 frames per second.
+ * |[
+ * gst-launch videotestsrc pattern=1 ! \
+ *   video/x-raw-rgb, framerate=\(fraction\)10/1, width=100, height=100 ! \
+ *   videomixer2 name=mix ! ffmpegcolorspace ! ximagesink \
+ *   videotestsrc !  \
+ *   video/x-raw-rgb, framerate=\(fraction\)5/1, width=320, height=240 ! mix.
+ * ]| A pipeline to demostrate bgra mixing. (This does not demonstrate alpha blending). 
+ * |[
+ * gst-launch videotestsrc pattern=1 ! \
+ *   video/x-raw-yuv,format =\(fourcc\)I420, framerate=\(fraction\)10/1, width=100, height=100 ! \
+ *   videomixer2 name=mix ! ffmpegcolorspace ! ximagesink \
+ *   videotestsrc ! \
+ *   video/x-raw-yuv,format=\(fourcc\)I420, framerate=\(fraction\)5/1, width=320, height=240 ! mix.
+ * ]| A pipeline to test I420
+ * |[
+ * gst-launch videomixer2 name=mixer sink_1::alpha=0.5 sink_1::xpos=50 sink_1::ypos=50 ! \
+ *   ffmpegcolorspace ! ximagesink \
+ *   videotestsrc pattern=snow timestamp-offset=3000000000 ! \
+ *   "video/x-raw-yuv,format=(fourcc)AYUV,width=640,height=480,framerate=(fraction)30/1" ! \
+ *   timeoverlay ! queue2 ! mixer. \
+ *   videotestsrc pattern=smpte ! \
+ *   "video/x-raw-yuv,format=(fourcc)AYUV,width=800,height=600,framerate=(fraction)10/1" ! \
+ *   timeoverlay ! queue2 ! mixer.
+ * ]| A pipeline to demonstrate synchronized mixing (the second stream starts after 3 seconds)
+ * </refsect2>
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <string.h>
+
+#include "videomixer2.h"
+#include "videomixer2pad.h"
+
+#include <gst/controller/gstcontroller.h>
+
+#ifdef DISABLE_ORC
+#define orc_memset memset
+#else
+#include <orc/orcfunctions.h>
+#endif
+
+GST_DEBUG_CATEGORY_STATIC (gst_videomixer2_debug);
+#define GST_CAT_DEFAULT gst_videomixer2_debug
+
+#define GST_VIDEO_MIXER2_GET_LOCK(mix) \
+  (GST_VIDEO_MIXER2(mix)->lock)
+#define GST_VIDEO_MIXER2_LOCK(mix) \
+  (g_mutex_lock(GST_VIDEO_MIXER2_GET_LOCK (mix)))
+#define GST_VIDEO_MIXER2_UNLOCK(mix) \
+  (g_mutex_unlock(GST_VIDEO_MIXER2_GET_LOCK (mix)))
+
+static GstStaticPadTemplate src_factory = GST_STATIC_PAD_TEMPLATE ("src",
+    GST_PAD_SRC,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("AYUV") ";" GST_VIDEO_CAPS_BGRA ";"
+        GST_VIDEO_CAPS_ARGB ";" GST_VIDEO_CAPS_RGBA ";" GST_VIDEO_CAPS_ABGR ";"
+        GST_VIDEO_CAPS_YUV ("Y444") ";" GST_VIDEO_CAPS_YUV ("Y42B") ";"
+        GST_VIDEO_CAPS_YUV ("YUY2") ";" GST_VIDEO_CAPS_YUV ("UYVY") ";"
+        GST_VIDEO_CAPS_YUV ("YVYU") ";"
+        GST_VIDEO_CAPS_YUV ("I420") ";" GST_VIDEO_CAPS_YUV ("YV12") ";"
+        GST_VIDEO_CAPS_YUV ("Y41B") ";" GST_VIDEO_CAPS_RGB ";"
+        GST_VIDEO_CAPS_BGR ";" GST_VIDEO_CAPS_xRGB ";" GST_VIDEO_CAPS_xBGR ";"
+        GST_VIDEO_CAPS_RGBx ";" GST_VIDEO_CAPS_BGRx)
+    );
+
+static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink_%d",
+    GST_PAD_SINK,
+    GST_PAD_REQUEST,
+    GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("AYUV") ";" GST_VIDEO_CAPS_BGRA ";"
+        GST_VIDEO_CAPS_ARGB ";" GST_VIDEO_CAPS_RGBA ";" GST_VIDEO_CAPS_ABGR ";"
+        GST_VIDEO_CAPS_YUV ("Y444") ";" GST_VIDEO_CAPS_YUV ("Y42B") ";"
+        GST_VIDEO_CAPS_YUV ("YUY2") ";" GST_VIDEO_CAPS_YUV ("UYVY") ";"
+        GST_VIDEO_CAPS_YUV ("YVYU") ";"
+        GST_VIDEO_CAPS_YUV ("I420") ";" GST_VIDEO_CAPS_YUV ("YV12") ";"
+        GST_VIDEO_CAPS_YUV ("Y41B") ";" GST_VIDEO_CAPS_RGB ";"
+        GST_VIDEO_CAPS_BGR ";" GST_VIDEO_CAPS_xRGB ";" GST_VIDEO_CAPS_xBGR ";"
+        GST_VIDEO_CAPS_RGBx ";" GST_VIDEO_CAPS_BGRx)
+    );
+
+static void gst_videomixer2_child_proxy_init (gpointer g_iface,
+    gpointer iface_data);
+static gboolean gst_videomixer2_push_sink_event (GstVideoMixer2 * mix,
+    GstEvent * event);
+static void gst_videomixer2_release_pad (GstElement * element, GstPad * pad);
+static void gst_videomixer2_reset_qos (GstVideoMixer2 * mix);
+
+static void
+_do_init (GType object_type)
+{
+  static const GInterfaceInfo child_proxy_info = {
+    (GInterfaceInitFunc) gst_videomixer2_child_proxy_init,
+    NULL,
+    NULL
+  };
+
+  g_type_add_interface_static (object_type, GST_TYPE_CHILD_PROXY,
+      &child_proxy_info);
+}
+
+struct _GstVideoMixer2Collect
+{
+  GstCollectData2 collect;      /* we extend the CollectData */
+
+  GstVideoMixer2Pad *mixpad;
+
+  GstBuffer *queued;            /* buffer for which we don't know the end time yet */
+
+  GstBuffer *buffer;            /* buffer that should be blended now */
+  GstClockTime start_time;
+  GstClockTime end_time;
+};
+
+#define DEFAULT_PAD_ZORDER 0
+#define DEFAULT_PAD_XPOS   0
+#define DEFAULT_PAD_YPOS   0
+#define DEFAULT_PAD_ALPHA  1.0
+enum
+{
+  PROP_PAD_0,
+  PROP_PAD_ZORDER,
+  PROP_PAD_XPOS,
+  PROP_PAD_YPOS,
+  PROP_PAD_ALPHA
+};
+
+G_DEFINE_TYPE (GstVideoMixer2Pad, gst_videomixer2_pad, GST_TYPE_PAD);
+
+static void
+gst_videomixer2_collect_free (GstCollectData2 * data)
+{
+  GstVideoMixer2Collect *cdata = (GstVideoMixer2Collect *) data;
+
+  gst_buffer_replace (&cdata->buffer, NULL);
+}
+
+static gboolean
+gst_videomixer2_update_src_caps (GstVideoMixer2 * mix)
+{
+  GSList *l;
+  gint best_width = -1, best_height = -1;
+  gdouble best_fps = -1, cur_fps;
+  gint best_fps_n = -1, best_fps_d = -1;
+  gboolean ret = TRUE;
+
+  GST_VIDEO_MIXER2_LOCK (mix);
+
+  for (l = mix->sinkpads; l; l = l->next) {
+    GstVideoMixer2Pad *mpad = l->data;
+    gint this_width, this_height;
+
+    if (mpad->fps_n == 0 || mpad->fps_d == 0 ||
+        mpad->width == 0 || mpad->height == 0)
+      continue;
+
+    this_width = mpad->width + MAX (mpad->xpos, 0);
+    this_height = mpad->height + MAX (mpad->ypos, 0);
+
+    if (best_width < this_width)
+      best_width = this_width;
+    if (best_height < this_height)
+      best_height = this_height;
+
+    if (mpad->fps_d == 0)
+      cur_fps = 0.0;
+    else
+      gst_util_fraction_to_double (mpad->fps_n, mpad->fps_d, &cur_fps);
+    if (best_fps < cur_fps) {
+      best_fps = cur_fps;
+      best_fps_n = mpad->fps_n;
+      best_fps_d = mpad->fps_d;
+    }
+  }
+
+  if (best_fps_n <= 0 && best_fps_d <= 0) {
+    best_fps_n = 25;
+    best_fps_d = 1;
+    best_fps = 25.0;
+  }
+
+  if (best_width > 0 && best_height > 0 && best_fps > 0) {
+    GstCaps *caps, *peercaps;
+    GstStructure *s;
+
+    if (mix->fps_n != best_fps_n || mix->fps_d != best_fps_d) {
+      if (mix->segment.last_stop != -1) {
+        mix->ts_offset = mix->segment.last_stop - mix->segment.start;
+        mix->nframes = 0;
+      }
+    }
+
+    caps = gst_video_format_new_caps (mix->format,
+        best_width, best_height, best_fps_n, best_fps_d,
+        mix->par_n, mix->par_d);
+
+    peercaps = gst_pad_peer_get_caps (mix->srcpad);
+    if (peercaps) {
+      GstCaps *tmp;
+
+      s = gst_caps_get_structure (caps, 0);
+      gst_structure_set (s, "width", GST_TYPE_INT_RANGE, 1, G_MAXINT, "height",
+          GST_TYPE_INT_RANGE, 1, G_MAXINT, "framerate", GST_TYPE_FRACTION_RANGE,
+          0, 1, G_MAXINT, 1, NULL);
+
+      tmp = gst_caps_intersect (caps, peercaps);
+      gst_caps_unref (caps);
+      gst_caps_unref (peercaps);
+      caps = tmp;
+      if (gst_caps_is_empty (caps)) {
+        ret = FALSE;
+        GST_VIDEO_MIXER2_UNLOCK (mix);
+        goto done;
+      }
+
+      gst_caps_truncate (caps);
+      s = gst_caps_get_structure (caps, 0);
+      gst_structure_fixate_field_nearest_int (s, "width", best_width);
+      gst_structure_fixate_field_nearest_int (s, "height", best_height);
+      gst_structure_fixate_field_nearest_fraction (s, "framerate", best_fps_n,
+          best_fps_d);
+
+      gst_structure_get_int (s, "width", &best_width);
+      gst_structure_get_int (s, "height", &best_height);
+      gst_structure_get_fraction (s, "fraction", &best_fps_n, &best_fps_d);
+    }
+
+    mix->fps_n = best_fps_n;
+    mix->fps_d = best_fps_d;
+    mix->width = best_width;
+    mix->height = best_height;
+
+    GST_VIDEO_MIXER2_UNLOCK (mix);
+    ret = gst_pad_set_caps (mix->srcpad, caps);
+    gst_caps_unref (caps);
+  } else {
+    GST_VIDEO_MIXER2_UNLOCK (mix);
+  }
+
+done:
+  return ret;
+}
+
+
+static gboolean
+gst_videomixer2_pad_sink_setcaps (GstPad * pad, GstCaps * caps)
+{
+  GstVideoMixer2 *mix;
+  GstVideoMixer2Pad *mixpad;
+  GstVideoFormat fmt;
+  gint width, height;
+  gint fps_n = 0, fps_d = 0;
+  gint par_n = 1, par_d = 1;
+  gboolean ret = FALSE;
+  GstStructure *s;
+
+  GST_INFO_OBJECT (pad, "Setting caps %" GST_PTR_FORMAT, caps);
+
+  mix = GST_VIDEO_MIXER2 (gst_pad_get_parent (pad));
+  mixpad = GST_VIDEO_MIXER2_PAD (pad);
+
+  if (!gst_video_format_parse_caps (caps, &fmt, &width, &height) ||
+      !gst_video_parse_caps_pixel_aspect_ratio (caps, &par_n, &par_d)) {
+    GST_ERROR_OBJECT (pad, "Failed to parse caps");
+    goto beach;
+  }
+
+  s = gst_caps_get_structure (caps, 0);
+  if (gst_structure_has_field (s, "framerate")
+      && !gst_video_parse_caps_framerate (caps, &fps_n, &fps_d)) {
+    GST_ERROR_OBJECT (pad, "Failed to parse caps");
+    goto beach;
+  }
+
+  GST_VIDEO_MIXER2_LOCK (mix);
+  if (mix->format != GST_VIDEO_FORMAT_UNKNOWN) {
+    if (mix->format != fmt || mix->par_n != par_n || mix->par_d != par_d) {
+      GST_ERROR_OBJECT (pad, "Caps not compatible with other pads' caps");
+      GST_VIDEO_MIXER2_UNLOCK (mix);
+      goto beach;
+    }
+  }
+
+  mix->format = fmt;
+  mix->par_n = par_n;
+  mix->par_d = par_d;
+  mixpad->fps_n = fps_n;
+  mixpad->fps_d = fps_d;
+  mixpad->width = width;
+  mixpad->height = height;
+
+  GST_VIDEO_MIXER2_UNLOCK (mix);
+
+  ret = gst_videomixer2_update_src_caps (mix);
+
+beach:
+  gst_object_unref (mix);
+
+  return ret;
+}
+
+static GstCaps *
+gst_videomixer2_pad_sink_getcaps (GstPad * pad)
+{
+  GstVideoMixer2 *mix;
+  GstCaps *srccaps;
+  GstStructure *s;
+  gint i, n;
+
+  mix = GST_VIDEO_MIXER2 (gst_pad_get_parent (pad));
+
+  srccaps = gst_pad_get_fixed_caps_func (GST_PAD (mix->srcpad));
+  srccaps = gst_caps_make_writable (srccaps);
+
+  n = gst_caps_get_size (srccaps);
+  for (i = 0; i < n; i++) {
+    s = gst_caps_get_structure (srccaps, i);
+    gst_structure_set (s, "width", GST_TYPE_INT_RANGE, 1, G_MAXINT,
+        "height", GST_TYPE_INT_RANGE, 1, G_MAXINT,
+        "framerate", GST_TYPE_FRACTION_RANGE, 0, 1, G_MAXINT, 1, NULL);
+    if (!gst_structure_has_field (s, "pixel-aspect-ratio"))
+      gst_structure_set (s, "pixel-aspect-ratio", GST_TYPE_FRACTION, 1, 1,
+          NULL);
+  }
+
+  GST_DEBUG_OBJECT (pad, "Returning %" GST_PTR_FORMAT, srccaps);
+
+  return srccaps;
+}
+
+static gboolean
+gst_videomixer2_pad_sink_acceptcaps (GstPad * pad, GstCaps * caps)
+{
+  gboolean ret;
+  GstVideoMixer2 *mix;
+  GstCaps *accepted_caps;
+  gint i, n;
+  GstStructure *s;
+
+  mix = GST_VIDEO_MIXER2 (gst_pad_get_parent (pad));
+  GST_DEBUG_OBJECT (pad, "%" GST_PTR_FORMAT, caps);
+
+  accepted_caps = gst_pad_get_fixed_caps_func (GST_PAD (mix->srcpad));
+  accepted_caps = gst_caps_make_writable (accepted_caps);
+  GST_LOG_OBJECT (pad, "src caps %" GST_PTR_FORMAT, accepted_caps);
+
+  n = gst_caps_get_size (accepted_caps);
+  for (i = 0; i < n; i++) {
+    s = gst_caps_get_structure (accepted_caps, i);
+    gst_structure_set (s, "width", GST_TYPE_INT_RANGE, 1, G_MAXINT,
+        "height", GST_TYPE_INT_RANGE, 1, G_MAXINT,
+        "framerate", GST_TYPE_FRACTION_RANGE, 0, 1, G_MAXINT, 1, NULL);
+    if (!gst_structure_has_field (s, "pixel-aspect-ratio"))
+      gst_structure_set (s, "pixel-aspect-ratio", GST_TYPE_FRACTION, 1, 1,
+          NULL);
+  }
+
+  ret = gst_caps_can_intersect (caps, accepted_caps);
+  GST_INFO_OBJECT (pad, "%saccepted caps %" GST_PTR_FORMAT, (ret ? "" : "not "),
+      caps);
+  GST_INFO_OBJECT (pad, "acceptable caps are %" GST_PTR_FORMAT, accepted_caps);
+
+  gst_caps_unref (accepted_caps);
+
+  gst_object_unref (mix);
+  return ret;
+}
+
+static void
+gst_videomixer2_pad_get_property (GObject * object, guint prop_id,
+    GValue * value, GParamSpec * pspec)
+{
+  GstVideoMixer2Pad *pad = GST_VIDEO_MIXER2_PAD (object);
+
+  switch (prop_id) {
+    case PROP_PAD_ZORDER:
+      g_value_set_uint (value, pad->zorder);
+      break;
+    case PROP_PAD_XPOS:
+      g_value_set_int (value, pad->xpos);
+      break;
+    case PROP_PAD_YPOS:
+      g_value_set_int (value, pad->ypos);
+      break;
+    case PROP_PAD_ALPHA:
+      g_value_set_double (value, pad->alpha);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static int
+pad_zorder_compare (const GstVideoMixer2Pad * pad1,
+    const GstVideoMixer2Pad * pad2)
+{
+  return pad1->zorder - pad2->zorder;
+}
+
+static void
+gst_videomixer2_pad_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec)
+{
+  GstVideoMixer2Pad *pad = GST_VIDEO_MIXER2_PAD (object);
+  GstVideoMixer2 *mix = GST_VIDEO_MIXER2 (gst_pad_get_parent (GST_PAD (pad)));
+
+  switch (prop_id) {
+    case PROP_PAD_ZORDER:
+      GST_VIDEO_MIXER2_LOCK (mix);
+      pad->zorder = g_value_get_uint (value);
+
+      mix->sinkpads = g_slist_sort (mix->sinkpads,
+          (GCompareFunc) pad_zorder_compare);
+      GST_VIDEO_MIXER2_UNLOCK (mix);
+      break;
+    case PROP_PAD_XPOS:
+      pad->xpos = g_value_get_int (value);
+      break;
+    case PROP_PAD_YPOS:
+      pad->ypos = g_value_get_int (value);
+      break;
+    case PROP_PAD_ALPHA:
+      pad->alpha = g_value_get_double (value);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+
+  gst_object_unref (mix);
+}
+
+static void
+gst_videomixer2_pad_class_init (GstVideoMixer2PadClass * klass)
+{
+  GObjectClass *gobject_class = (GObjectClass *) klass;
+
+  gobject_class->set_property = gst_videomixer2_pad_set_property;
+  gobject_class->get_property = gst_videomixer2_pad_get_property;
+
+  g_object_class_install_property (gobject_class, PROP_PAD_ZORDER,
+      g_param_spec_uint ("zorder", "Z-Order", "Z Order of the picture",
+          0, 10000, DEFAULT_PAD_ZORDER,
+          G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
+  g_object_class_install_property (gobject_class, PROP_PAD_XPOS,
+      g_param_spec_int ("xpos", "X Position", "X Position of the picture",
+          G_MININT, G_MAXINT, DEFAULT_PAD_XPOS,
+          G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
+  g_object_class_install_property (gobject_class, PROP_PAD_YPOS,
+      g_param_spec_int ("ypos", "Y Position", "Y Position of the picture",
+          G_MININT, G_MAXINT, DEFAULT_PAD_YPOS,
+          G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
+  g_object_class_install_property (gobject_class, PROP_PAD_ALPHA,
+      g_param_spec_double ("alpha", "Alpha", "Alpha of the picture", 0.0, 1.0,
+          DEFAULT_PAD_ALPHA,
+          G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
+}
+
+static void
+gst_videomixer2_pad_init (GstVideoMixer2Pad * mixerpad)
+{
+  /* setup some pad functions */
+  gst_pad_set_setcaps_function (GST_PAD (mixerpad),
+      gst_videomixer2_pad_sink_setcaps);
+  gst_pad_set_acceptcaps_function (GST_PAD (mixerpad),
+      GST_DEBUG_FUNCPTR (gst_videomixer2_pad_sink_acceptcaps));
+  gst_pad_set_getcaps_function (GST_PAD (mixerpad),
+      gst_videomixer2_pad_sink_getcaps);
+
+  mixerpad->zorder = DEFAULT_PAD_ZORDER;
+  mixerpad->xpos = DEFAULT_PAD_XPOS;
+  mixerpad->ypos = DEFAULT_PAD_YPOS;
+  mixerpad->alpha = DEFAULT_PAD_ALPHA;
+}
+
+/* GstVideoMixer2 */
+#define DEFAULT_BACKGROUND VIDEO_MIXER2_BACKGROUND_CHECKER
+enum
+{
+  PROP_0,
+  PROP_BACKGROUND
+};
+
+#define GST_TYPE_VIDEO_MIXER2_BACKGROUND (gst_videomixer2_background_get_type())
+static GType
+gst_videomixer2_background_get_type (void)
+{
+  static GType video_mixer_background_type = 0;
+
+  static const GEnumValue video_mixer_background[] = {
+    {VIDEO_MIXER2_BACKGROUND_CHECKER, "Checker pattern", "checker"},
+    {VIDEO_MIXER2_BACKGROUND_BLACK, "Black", "black"},
+    {VIDEO_MIXER2_BACKGROUND_WHITE, "White", "white"},
+    {VIDEO_MIXER2_BACKGROUND_TRANSPARENT,
+        "Transparent Background to enable further mixing", "transparent"},
+    {0, NULL, NULL},
+  };
+
+  if (!video_mixer_background_type) {
+    video_mixer_background_type =
+        g_enum_register_static ("GstVideoMixer2Background",
+        video_mixer_background);
+  }
+  return video_mixer_background_type;
+}
+
+
+GST_BOILERPLATE_FULL (GstVideoMixer2, gst_videomixer2, GstElement,
+    GST_TYPE_ELEMENT, _do_init);
+
+static void
+gst_videomixer2_update_qos (GstVideoMixer2 * mix, gdouble proportion,
+    GstClockTimeDiff diff, GstClockTime timestamp)
+{
+  GST_DEBUG_OBJECT (mix,
+      "Updating QoS: proportion %lf, diff %s%" GST_TIME_FORMAT ", timestamp %"
+      GST_TIME_FORMAT, proportion, (diff < 0) ? "-" : "",
+      GST_TIME_ARGS (ABS (diff)), GST_TIME_ARGS (timestamp));
+
+  GST_OBJECT_LOCK (mix);
+  mix->proportion = proportion;
+  if (G_LIKELY (timestamp != GST_CLOCK_TIME_NONE)) {
+    if (G_UNLIKELY (diff > 0))
+      mix->earliest_time =
+          timestamp + 2 * diff + gst_util_uint64_scale_int (GST_SECOND,
+          mix->fps_d, mix->fps_n);
+    else
+      mix->earliest_time = timestamp + diff;
+  } else {
+    mix->earliest_time = GST_CLOCK_TIME_NONE;
+  }
+  GST_OBJECT_UNLOCK (mix);
+}
+
+static void
+gst_videomixer2_reset_qos (GstVideoMixer2 * mix)
+{
+  gst_videomixer2_update_qos (mix, 0.5, 0, GST_CLOCK_TIME_NONE);
+  mix->qos_processed = mix->qos_dropped = 0;
+}
+
+static void
+gst_videomixer2_read_qos (GstVideoMixer2 * mix, gdouble * proportion,
+    GstClockTime * time)
+{
+  GST_OBJECT_LOCK (mix);
+  *proportion = mix->proportion;
+  *time = mix->earliest_time;
+  GST_OBJECT_UNLOCK (mix);
+}
+
+static void
+gst_videomixer2_reset (GstVideoMixer2 * mix)
+{
+  GSList *l;
+
+  mix->format = GST_VIDEO_FORMAT_UNKNOWN;
+  mix->width = mix->height = 0;
+  mix->fps_n = mix->fps_d = 0;
+  mix->par_n = mix->par_d = 0;
+  mix->ts_offset = 0;
+  mix->nframes = 0;
+
+  gst_segment_init (&mix->segment, GST_FORMAT_TIME);
+  mix->segment.last_stop = -1;
+
+  gst_videomixer2_reset_qos (mix);
+
+  for (l = mix->sinkpads; l; l = l->next) {
+    GstVideoMixer2Pad *p = l->data;
+    GstVideoMixer2Collect *mixcol = p->mixcol;
+
+    gst_buffer_replace (&mixcol->buffer, NULL);
+    mixcol->start_time = -1;
+    mixcol->end_time = -1;
+
+    p->fps_n = p->fps_d = 0;
+    p->width = p->height = 0;
+  }
+
+  mix->newseg_pending = TRUE;
+  mix->flush_stop_pending = FALSE;
+}
+
+/*  1 == OK
+ *  0 == need more data
+ * -1 == EOS
+ * -2 == error
+ */
+static gint
+gst_videomixer2_fill_queues (GstVideoMixer2 * mix,
+    GstClockTime output_start_time, GstClockTime output_end_time)
+{
+  GSList *l;
+  gboolean eos = TRUE;
+  gboolean need_more_data = FALSE;
+
+  for (l = mix->sinkpads; l; l = l->next) {
+    GstVideoMixer2Pad *pad = l->data;
+    GstVideoMixer2Collect *mixcol = pad->mixcol;
+    GstSegment *segment = &pad->mixcol->collect.segment;
+    GstBuffer *buf;
+
+    buf = gst_collect_pads2_peek (mix->collect, &mixcol->collect);
+    if (buf) {
+      GstClockTime start_time, end_time;
+
+      start_time = GST_BUFFER_TIMESTAMP (buf);
+      if (start_time == -1) {
+        gst_buffer_unref (buf);
+        GST_ERROR_OBJECT (pad, "Need timestamped buffers!");
+        return -2;
+      }
+
+      /* FIXME: Make all this work with negative rates */
+
+      if ((mixcol->buffer && start_time < GST_BUFFER_TIMESTAMP (mixcol->buffer))
+          || (mixcol->queued
+              && start_time < GST_BUFFER_TIMESTAMP (mixcol->queued))) {
+        GST_WARNING_OBJECT (pad, "Buffer from the past, dropping");
+        gst_buffer_unref (buf);
+        buf = gst_collect_pads2_pop (mix->collect, &mixcol->collect);
+        gst_buffer_unref (buf);
+        need_more_data = TRUE;
+        continue;
+      }
+
+      if (mixcol->queued) {
+        end_time = start_time - GST_BUFFER_TIMESTAMP (mixcol->queued);
+        start_time = GST_BUFFER_TIMESTAMP (mixcol->queued);
+        gst_buffer_unref (buf);
+        buf = gst_buffer_ref (mixcol->queued);
+      } else {
+        end_time = GST_BUFFER_DURATION (buf);
+
+        if (end_time == -1) {
+          mixcol->queued = buf;
+          need_more_data = TRUE;
+          continue;
+        }
+      }
+
+      g_assert (start_time != -1 && end_time != -1);
+      end_time += start_time;   /* convert from duration to position */
+
+      if (mixcol->end_time != -1 && mixcol->end_time > end_time) {
+        GST_WARNING_OBJECT (pad, "Buffer from the past, dropping");
+        if (buf == mixcol->queued) {
+          gst_buffer_unref (buf);
+          gst_buffer_replace (&mixcol->queued, NULL);
+        } else {
+          gst_buffer_unref (buf);
+          buf = gst_collect_pads2_pop (mix->collect, &mixcol->collect);
+          gst_buffer_unref (buf);
+        }
+
+        need_more_data = TRUE;
+        continue;
+      }
+
+      /* Check if it's inside the segment */
+      if (start_time >= segment->stop || end_time < segment->start) {
+        GST_DEBUG_OBJECT (pad, "Buffer outside the segment");
+
+        if (buf == mixcol->queued) {
+          gst_buffer_unref (buf);
+          gst_buffer_replace (&mixcol->queued, NULL);
+        } else {
+          gst_buffer_unref (buf);
+          buf = gst_collect_pads2_pop (mix->collect, &mixcol->collect);
+          gst_buffer_unref (buf);
+        }
+
+        need_more_data = TRUE;
+        continue;
+      }
+
+      /* Clip to segment and convert to running time */
+      start_time = MAX (start_time, segment->start);
+      if (segment->stop != -1)
+        end_time = MIN (end_time, segment->stop);
+      start_time =
+          gst_segment_to_running_time (segment, GST_FORMAT_TIME, start_time);
+      end_time =
+          gst_segment_to_running_time (segment, GST_FORMAT_TIME, end_time);
+      g_assert (start_time != -1 && end_time != -1);
+
+      /* Convert to the output segment rate */
+      if (mix->segment.abs_rate != 1.0) {
+        start_time *= mix->segment.abs_rate;
+        end_time *= mix->segment.abs_rate;
+      }
+
+      if (end_time >= output_start_time && start_time < output_end_time) {
+        GST_DEBUG_OBJECT (pad,
+            "Taking new buffer with start time %" GST_TIME_FORMAT,
+            GST_TIME_ARGS (start_time));
+        gst_buffer_replace (&mixcol->buffer, buf);
+        mixcol->start_time = start_time;
+        mixcol->end_time = end_time;
+
+        if (buf == mixcol->queued) {
+          gst_buffer_unref (buf);
+          gst_buffer_replace (mixcol->queued, NULL);
+        } else {
+          gst_buffer_unref (buf);
+          buf = gst_collect_pads2_pop (mix->collect, &mixcol->collect);
+          gst_buffer_unref (buf);
+        }
+        eos = FALSE;
+      } else if (start_time >= output_end_time) {
+        GST_DEBUG_OBJECT (pad, "Keeping buffer until %" GST_TIME_FORMAT,
+            GST_TIME_ARGS (start_time));
+        eos = FALSE;
+      } else {
+        GST_DEBUG_OBJECT (pad, "Too old buffer -- dropping");
+        if (buf == mixcol->queued) {
+          gst_buffer_unref (buf);
+          gst_buffer_replace (&mixcol->queued, NULL);
+        } else {
+          gst_buffer_unref (buf);
+          buf = gst_collect_pads2_pop (mix->collect, &mixcol->collect);
+          gst_buffer_unref (buf);
+        }
+
+        need_more_data = TRUE;
+        continue;
+      }
+    } else {
+      if (mixcol->end_time != -1) {
+        if (mixcol->end_time < output_start_time) {
+          gst_buffer_replace (&mixcol->buffer, NULL);
+          mixcol->start_time = mixcol->end_time = -1;
+          if (!GST_COLLECT_PADS2_STATE_IS_SET (mixcol,
+                  GST_COLLECT_PADS2_STATE_EOS))
+            need_more_data = TRUE;
+        } else {
+          eos = FALSE;
+        }
+      }
+    }
+  }
+
+  if (need_more_data)
+    return 0;
+  if (eos)
+    return -1;
+
+  return 1;
+}
+
+static GstFlowReturn
+gst_videomixer2_blend_buffers (GstVideoMixer2 * mix,
+    GstClockTime output_start_time, GstClockTime output_end_time,
+    GstBuffer ** outbuf)
+{
+  GSList *l;
+  GstFlowReturn ret;
+  guint outsize;
+  BlendFunction composite;
+
+  outsize = gst_video_format_get_size (mix->format, mix->width, mix->height);
+  ret = gst_pad_alloc_buffer_and_set_caps (mix->srcpad, GST_BUFFER_OFFSET_NONE,
+      outsize, GST_PAD_CAPS (mix->srcpad), outbuf);
+  if (ret != GST_FLOW_OK)
+    return ret;
+
+  GST_BUFFER_TIMESTAMP (*outbuf) = output_start_time;
+  GST_BUFFER_DURATION (*outbuf) = output_end_time - output_start_time;
+
+  /* default to blending */
+  composite = mix->blend;
+  switch (mix->background) {
+    case VIDEO_MIXER2_BACKGROUND_CHECKER:
+      mix->fill_checker (GST_BUFFER_DATA (*outbuf), mix->width, mix->height);
+      break;
+    case VIDEO_MIXER2_BACKGROUND_BLACK:
+      mix->fill_color (GST_BUFFER_DATA (*outbuf), mix->width,
+          mix->height, 16, 128, 128);
+      break;
+    case VIDEO_MIXER2_BACKGROUND_WHITE:
+      mix->fill_color (GST_BUFFER_DATA (*outbuf), mix->width,
+          mix->height, 240, 128, 128);
+      break;
+    case VIDEO_MIXER2_BACKGROUND_TRANSPARENT:
+      orc_memset (GST_BUFFER_DATA (*outbuf), 0,
+          gst_video_format_get_row_stride (mix->format, 0,
+              mix->width) * mix->height);
+      /* use overlay to keep background transparent */
+      composite = mix->overlay;
+      break;
+  }
+
+  for (l = mix->sinkpads; l; l = l->next) {
+    GstVideoMixer2Pad *pad = l->data;
+    GstVideoMixer2Collect *mixcol = pad->mixcol;
+
+    if (mixcol->buffer != NULL) {
+      GstClockTime timestamp;
+      gint64 stream_time;
+      GstSegment *seg;
+
+      seg = &mixcol->collect.segment;
+
+      timestamp = GST_BUFFER_TIMESTAMP (mixcol->buffer);
+
+      stream_time =
+          gst_segment_to_stream_time (seg, GST_FORMAT_TIME, timestamp);
+
+      /* sync object properties on stream time */
+      if (GST_CLOCK_TIME_IS_VALID (stream_time))
+        gst_object_sync_values (G_OBJECT (pad), stream_time);
+
+      composite (GST_BUFFER_DATA (mixcol->buffer),
+          pad->xpos, pad->ypos, pad->width, pad->height, pad->alpha,
+          GST_BUFFER_DATA (*outbuf), mix->width, mix->height);
+    }
+  }
+
+  return GST_FLOW_OK;
+}
+
+/* Perform qos calculations before processing the next frame. Returns TRUE if
+ * the frame should be processed, FALSE if the frame can be dropped entirely */
+static gint64
+gst_videomixer2_do_qos (GstVideoMixer2 * mix, GstClockTime timestamp)
+{
+  GstClockTime qostime, earliest_time;
+  gdouble proportion;
+  gint64 jitter;
+
+  /* no timestamp, can't do QoS => process frame */
+  if (G_UNLIKELY (!GST_CLOCK_TIME_IS_VALID (timestamp))) {
+    GST_LOG_OBJECT (mix, "invalid timestamp, can't do QoS, process frame");
+    return -1;
+  }
+
+  /* get latest QoS observation values */
+  gst_videomixer2_read_qos (mix, &proportion, &earliest_time);
+
+  /* skip qos if we have no observation (yet) => process frame */
+  if (G_UNLIKELY (!GST_CLOCK_TIME_IS_VALID (earliest_time))) {
+    GST_LOG_OBJECT (mix, "no observation yet, process frame");
+    return -1;
+  }
+
+  /* qos is done on running time */
+  qostime =
+      gst_segment_to_running_time (&mix->segment, GST_FORMAT_TIME, timestamp);
+
+  /* see how our next timestamp relates to the latest qos timestamp */
+  GST_LOG_OBJECT (mix, "qostime %" GST_TIME_FORMAT ", earliest %"
+      GST_TIME_FORMAT, GST_TIME_ARGS (qostime), GST_TIME_ARGS (earliest_time));
+
+  jitter = GST_CLOCK_DIFF (qostime, earliest_time);
+  if (qostime != GST_CLOCK_TIME_NONE && jitter > 0) {
+    GST_DEBUG_OBJECT (mix, "we are late, drop frame");
+    return jitter;
+  }
+
+  GST_LOG_OBJECT (mix, "process frame");
+  return jitter;
+}
+
+static GstFlowReturn
+gst_videomixer2_collected (GstCollectPads2 * pads, GstVideoMixer2 * mix)
+{
+  GstFlowReturn ret;
+  GstClockTime output_start_time, output_end_time;
+  GstBuffer *outbuf = NULL;
+  gint res;
+  gint64 jitter;
+
+  /* If we're not negotiated yet... */
+  if (mix->format == GST_VIDEO_FORMAT_UNKNOWN)
+    return GST_FLOW_NOT_NEGOTIATED;
+
+  if (g_atomic_int_compare_and_exchange (&mix->flush_stop_pending, TRUE, FALSE)) {
+    GST_DEBUG_OBJECT (mix, "pending flush stop");
+    gst_pad_push_event (mix->srcpad, gst_event_new_flush_stop ());
+  }
+
+  GST_VIDEO_MIXER2_LOCK (mix);
+
+  if (mix->newseg_pending) {
+    GST_DEBUG_OBJECT (mix, "Sending NEWSEGMENT event");
+    if (!gst_pad_push_event (mix->srcpad, gst_event_new_new_segment_full (FALSE,
+                mix->segment.rate, mix->segment.applied_rate,
+                mix->segment.format, mix->segment.start, mix->segment.stop,
+                mix->segment.time))) {
+      ret = GST_FLOW_ERROR;
+      goto done;
+    }
+    mix->newseg_pending = FALSE;
+  }
+
+  if (mix->segment.last_stop == -1)
+    output_start_time = mix->segment.start;
+  else
+    output_start_time = mix->segment.last_stop;
+
+  if (output_start_time >= mix->segment.stop) {
+    GST_DEBUG_OBJECT (mix, "Segment done");
+    gst_pad_push_event (mix->srcpad, gst_event_new_eos ());
+    ret = GST_FLOW_UNEXPECTED;
+    goto done;
+  }
+
+  output_end_time =
+      mix->ts_offset + gst_util_uint64_scale (mix->nframes + 1,
+      GST_SECOND * mix->fps_d, mix->fps_n);
+  if (mix->segment.stop != -1)
+    output_end_time = MIN (output_end_time, mix->segment.stop);
+
+  res = gst_videomixer2_fill_queues (mix, output_start_time, output_end_time);
+
+  if (res == 0) {
+    GST_DEBUG_OBJECT (mix, "Need more data for decisions");
+    ret = GST_FLOW_OK;
+    goto done;
+  } else if (res == -1) {
+    GST_DEBUG_OBJECT (mix, "All sinkpads are EOS -- forwarding");
+    gst_pad_push_event (mix->srcpad, gst_event_new_eos ());
+    ret = GST_FLOW_UNEXPECTED;
+    goto done;
+  } else if (res == -2) {
+    GST_ERROR_OBJECT (mix, "Error collecting buffers");
+    ret = GST_FLOW_ERROR;
+    goto done;
+  }
+
+  jitter = gst_videomixer2_do_qos (mix, output_start_time);
+  if (jitter <= 0) {
+    ret =
+        gst_videomixer2_blend_buffers (mix, output_start_time,
+        output_end_time, &outbuf);
+    mix->qos_processed++;
+  } else {
+    GstMessage *msg;
+
+    mix->qos_dropped++;
+
+    /* TODO: live */
+    msg =
+        gst_message_new_qos (GST_OBJECT_CAST (mix), FALSE,
+        gst_segment_to_running_time (&mix->segment, GST_FORMAT_TIME,
+            output_start_time), gst_segment_to_stream_time (&mix->segment,
+            GST_FORMAT_TIME, output_start_time), output_start_time,
+        output_end_time - output_start_time);
+    gst_message_set_qos_values (msg, jitter, mix->proportion, 1000000);
+    gst_message_set_qos_stats (msg, GST_FORMAT_BUFFERS, mix->qos_processed,
+        mix->qos_dropped);
+    gst_element_post_message (GST_ELEMENT_CAST (mix), msg);
+
+    ret = GST_FLOW_OK;
+  }
+
+  gst_segment_set_last_stop (&mix->segment, GST_FORMAT_TIME, output_end_time);
+  mix->nframes++;
+
+  GST_VIDEO_MIXER2_UNLOCK (mix);
+  if (outbuf) {
+    GST_LOG_OBJECT (mix,
+        "Pushing buffer with ts %" GST_TIME_FORMAT " and duration %"
+        GST_TIME_FORMAT, GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (outbuf)),
+        GST_TIME_ARGS (GST_BUFFER_DURATION (outbuf)));
+    ret = gst_pad_push (mix->srcpad, outbuf);
+  }
+  GST_VIDEO_MIXER2_LOCK (mix);
+
+done:
+  GST_VIDEO_MIXER2_UNLOCK (mix);
+
+  return ret;
+}
+
+static GstCaps *
+gst_videomixer2_src_getcaps (GstPad * pad)
+{
+  GstVideoMixer2 *mix = GST_VIDEO_MIXER2 (gst_pad_get_parent (pad));
+  GstCaps *caps;
+  GstStructure *s;
+  gint n;
+
+  if (mix->format != GST_VIDEO_FORMAT_UNKNOWN) {
+    caps = gst_caps_copy (GST_PAD_CAPS (mix->srcpad));
+  } else {
+    caps = gst_caps_copy (gst_pad_get_pad_template_caps (mix->srcpad));
+  }
+
+  n = gst_caps_get_size (caps) - 1;
+  for (; n >= 0; n--) {
+    s = gst_caps_get_structure (caps, n);
+    gst_structure_set (s, "width", GST_TYPE_INT_RANGE, 1, G_MAXINT,
+        "height", GST_TYPE_INT_RANGE, 1, G_MAXINT, NULL);
+    if (mix->fps_d != 0) {
+      gst_structure_set (s,
+          "framerate", GST_TYPE_FRACTION_RANGE, 0, 1, G_MAXINT, 1, NULL);
+    }
+  }
+
+  gst_object_unref (mix);
+
+  return caps;
+}
+
+static gboolean
+gst_videomixer2_query_duration (GstVideoMixer2 * mix, GstQuery * query)
+{
+  gint64 max;
+  gboolean res;
+  GstFormat format;
+  GstIterator *it;
+  gboolean done;
+
+  /* parse format */
+  gst_query_parse_duration (query, &format, NULL);
+
+  max = -1;
+  res = TRUE;
+  done = FALSE;
+
+  /* Take maximum of all durations */
+  it = gst_element_iterate_sink_pads (GST_ELEMENT_CAST (mix));
+  while (!done) {
+    GstIteratorResult ires;
+    gpointer item;
+
+    ires = gst_iterator_next (it, &item);
+    switch (ires) {
+      case GST_ITERATOR_DONE:
+        done = TRUE;
+        break;
+      case GST_ITERATOR_OK:
+      {
+        GstPad *pad = GST_PAD_CAST (item);
+        gint64 duration;
+
+        /* ask sink peer for duration */
+        res &= gst_pad_query_peer_duration (pad, &format, &duration);
+        /* take max from all valid return values */
+        if (res) {
+          /* valid unknown length, stop searching */
+          if (duration == -1) {
+            max = duration;
+            done = TRUE;
+          }
+          /* else see if bigger than current max */
+          else if (duration > max)
+            max = duration;
+        }
+        gst_object_unref (pad);
+        break;
+      }
+      case GST_ITERATOR_RESYNC:
+        max = -1;
+        res = TRUE;
+        gst_iterator_resync (it);
+        break;
+      default:
+        res = FALSE;
+        done = TRUE;
+        break;
+    }
+  }
+  gst_iterator_free (it);
+
+  if (res) {
+    /* and store the max */
+    GST_DEBUG_OBJECT (mix, "Total duration in format %s: %"
+        GST_TIME_FORMAT, gst_format_get_name (format), GST_TIME_ARGS (max));
+    gst_query_set_duration (query, format, max);
+  }
+
+  return res;
+}
+
+static gboolean
+gst_videomixer2_query_latency (GstVideoMixer2 * mix, GstQuery * query)
+{
+  GstClockTime min, max;
+  gboolean live;
+  gboolean res;
+  GstIterator *it;
+  gboolean done;
+
+  res = TRUE;
+  done = FALSE;
+  live = FALSE;
+  min = 0;
+  max = GST_CLOCK_TIME_NONE;
+
+  /* Take maximum of all latency values */
+  it = gst_element_iterate_sink_pads (GST_ELEMENT_CAST (mix));
+  while (!done) {
+    GstIteratorResult ires;
+    gpointer item;
+
+    ires = gst_iterator_next (it, &item);
+    switch (ires) {
+      case GST_ITERATOR_DONE:
+        done = TRUE;
+        break;
+      case GST_ITERATOR_OK:
+      {
+        GstPad *pad = GST_PAD_CAST (item);
+        GstQuery *peerquery;
+        GstClockTime min_cur, max_cur;
+        gboolean live_cur;
+
+        peerquery = gst_query_new_latency ();
+
+        /* Ask peer for latency */
+        res &= gst_pad_peer_query (pad, peerquery);
+
+        /* take max from all valid return values */
+        if (res) {
+          gst_query_parse_latency (peerquery, &live_cur, &min_cur, &max_cur);
+
+          if (min_cur > min)
+            min = min_cur;
+
+          if (max_cur != GST_CLOCK_TIME_NONE &&
+              ((max != GST_CLOCK_TIME_NONE && max_cur > max) ||
+                  (max == GST_CLOCK_TIME_NONE)))
+            max = max_cur;
+
+          live = live || live_cur;
+        }
+
+        gst_query_unref (peerquery);
+        gst_object_unref (pad);
+        break;
+      }
+      case GST_ITERATOR_RESYNC:
+        live = FALSE;
+        min = 0;
+        max = GST_CLOCK_TIME_NONE;
+        res = TRUE;
+        gst_iterator_resync (it);
+        break;
+      default:
+        res = FALSE;
+        done = TRUE;
+        break;
+    }
+  }
+  gst_iterator_free (it);
+
+  if (res) {
+    /* store the results */
+    GST_DEBUG_OBJECT (mix, "Calculated total latency: live %s, min %"
+        GST_TIME_FORMAT ", max %" GST_TIME_FORMAT,
+        (live ? "yes" : "no"), GST_TIME_ARGS (min), GST_TIME_ARGS (max));
+    gst_query_set_latency (query, live, min, max);
+  }
+
+  return res;
+}
+
+static gboolean
+gst_videomixer2_src_query (GstPad * pad, GstQuery * query)
+{
+  GstVideoMixer2 *mix = GST_VIDEO_MIXER2 (gst_pad_get_parent (pad));
+  gboolean res = FALSE;
+
+  switch (GST_QUERY_TYPE (query)) {
+    case GST_QUERY_POSITION:
+    {
+      GstFormat format;
+
+      gst_query_parse_position (query, &format, NULL);
+
+      switch (format) {
+        case GST_FORMAT_TIME:
+          gst_query_set_position (query, format,
+              gst_segment_to_stream_time (&mix->segment, GST_FORMAT_TIME,
+                  mix->segment.last_stop));
+          res = TRUE;
+          break;
+        default:
+          break;
+      }
+      break;
+    }
+    case GST_QUERY_DURATION:
+      res = gst_videomixer2_query_duration (mix, query);
+      break;
+    case GST_QUERY_LATENCY:
+      res = gst_videomixer2_query_latency (mix, query);
+      break;
+    default:
+      /* FIXME, needs a custom query handler because we have multiple
+       * sinkpads */
+      res = FALSE;
+      gst_query_unref (query);
+      break;
+  }
+
+  gst_object_unref (mix);
+  return res;
+}
+
+static gboolean
+gst_videomixer2_src_event (GstPad * pad, GstEvent * event)
+{
+  GstVideoMixer2 *mix = GST_VIDEO_MIXER2 (gst_pad_get_parent (pad));
+  gboolean result;
+
+  switch (GST_EVENT_TYPE (event)) {
+    case GST_EVENT_QOS:{
+      GstClockTimeDiff diff;
+      GstClockTime timestamp;
+      gdouble proportion;
+
+      gst_event_parse_qos (event, &proportion, &diff, &timestamp);
+
+      gst_videomixer2_update_qos (mix, proportion, diff, timestamp);
+
+      result = gst_videomixer2_push_sink_event (mix, event);
+      break;
+    }
+    case GST_EVENT_SEEK:
+    {
+      gdouble rate;
+      GstFormat fmt;
+      GstSeekFlags flags;
+      GstSeekType start_type, stop_type;
+      gint64 start, stop;
+      GSList *l;
+      gdouble abs_rate;
+
+      /* parse the seek parameters */
+      gst_event_parse_seek (event, &rate, &fmt, &flags, &start_type,
+          &start, &stop_type, &stop);
+
+      if (rate <= 0.0) {
+        GST_ERROR_OBJECT (mix, "Negative rates not supported yet");
+        result = FALSE;
+        gst_event_unref (event);
+        break;
+      }
+
+      GST_DEBUG_OBJECT (mix, "Handling SEEK event");
+
+      /* check if we are flushing */
+      if (flags & GST_SEEK_FLAG_FLUSH) {
+        /* flushing seek, start flush downstream, the flush will be done
+         * when all pads received a FLUSH_STOP. */
+        gst_pad_push_event (mix->srcpad, gst_event_new_flush_start ());
+
+        /* make sure we accept nothing anymore and return WRONG_STATE */
+        gst_collect_pads2_set_flushing (mix->collect, TRUE);
+      }
+
+      /* now wait for the collected to be finished and mark a new
+       * segment */
+      GST_COLLECT_PADS2_STREAM_LOCK (mix->collect);
+
+      abs_rate = ABS (rate);
+
+      GST_VIDEO_MIXER2_LOCK (mix);
+      for (l = mix->sinkpads; l; l = l->next) {
+        GstVideoMixer2Pad *p = l->data;
+
+        if (flags & GST_SEEK_FLAG_FLUSH) {
+          gst_buffer_replace (&p->mixcol->buffer, NULL);
+          p->mixcol->start_time = p->mixcol->end_time = -1;
+          continue;
+        }
+
+        /* Convert to the output segment rate */
+        if (mix->segment.abs_rate != abs_rate) {
+          if (mix->segment.abs_rate != 1.0 && p->mixcol->buffer) {
+            p->mixcol->start_time /= mix->segment.abs_rate;
+            p->mixcol->end_time /= mix->segment.abs_rate;
+          }
+          if (abs_rate != 1.0 && p->mixcol->buffer) {
+            p->mixcol->start_time *= abs_rate;
+            p->mixcol->end_time *= abs_rate;
+          }
+        }
+      }
+      GST_VIDEO_MIXER2_UNLOCK (mix);
+
+      gst_segment_set_seek (&mix->segment, rate, fmt, flags, start_type, start,
+          stop_type, stop, NULL);
+      mix->segment.last_stop = -1;
+      mix->ts_offset = 0;
+      mix->nframes = 0;
+      mix->newseg_pending = TRUE;
+
+      if (flags & GST_SEEK_FLAG_FLUSH) {
+        gst_collect_pads2_set_flushing (mix->collect, FALSE);
+
+        /* we can't send FLUSH_STOP here since upstream could start pushing data
+         * after we unlock mix->collect.
+         * We set flush_stop_pending to TRUE instead and send FLUSH_STOP after
+         * forwarding the seek upstream or from gst_videomixer_collected,
+         * whichever happens first.
+         */
+        mix->flush_stop_pending = TRUE;
+      }
+
+      GST_COLLECT_PADS2_STREAM_UNLOCK (mix->collect);
+
+      gst_videomixer2_reset_qos (mix);
+
+      result = gst_videomixer2_push_sink_event (mix, event);
+
+      if (g_atomic_int_compare_and_exchange (&mix->flush_stop_pending, TRUE,
+              FALSE)) {
+        GST_DEBUG_OBJECT (mix, "pending flush stop");
+        gst_pad_push_event (mix->srcpad, gst_event_new_flush_stop ());
+      }
+
+      break;
+    }
+    case GST_EVENT_NAVIGATION:
+      /* navigation is rather pointless. */
+      result = FALSE;
+      gst_event_unref (event);
+      break;
+    default:
+      /* just forward the rest for now */
+      result = gst_videomixer2_push_sink_event (mix, event);
+      break;
+  }
+  gst_object_unref (mix);
+
+  return result;
+}
+
+static gboolean
+gst_videomixer2_src_setcaps (GstPad * pad, GstCaps * caps)
+{
+  GstVideoMixer2 *mix = GST_VIDEO_MIXER2 (gst_pad_get_parent_element (pad));
+  gboolean ret = FALSE;
+  GstVideoFormat fmt;
+  gint width, height;
+  gint fps_n, fps_d;
+  gint par_n, par_d;
+
+  GST_INFO_OBJECT (pad, "set src caps: %" GST_PTR_FORMAT, caps);
+
+  mix->blend = NULL;
+  mix->overlay = NULL;
+  mix->fill_checker = NULL;
+  mix->fill_color = NULL;
+
+  if (!gst_video_format_parse_caps (caps, &fmt, &width, &height) ||
+      !gst_video_parse_caps_framerate (caps, &fps_n, &fps_d) ||
+      !gst_video_parse_caps_pixel_aspect_ratio (caps, &par_n, &par_d))
+    goto done;
+
+  GST_VIDEO_MIXER2_LOCK (mix);
+
+  if (mix->fps_n != fps_n || mix->fps_d != fps_d) {
+    if (mix->segment.last_stop != -1) {
+      mix->ts_offset = mix->segment.last_stop - mix->segment.start;
+      mix->nframes = 0;
+    }
+    gst_videomixer2_reset_qos (mix);
+  }
+
+  mix->format = fmt;
+  mix->width = width;
+  mix->height = height;
+  mix->fps_n = fps_n;
+  mix->fps_d = fps_d;
+  mix->par_n = par_n;
+  mix->par_d = par_d;
+
+  switch (mix->format) {
+    case GST_VIDEO_FORMAT_AYUV:
+      mix->blend = gst_video_mixer_blend_ayuv;
+      mix->overlay = gst_video_mixer_overlay_ayuv;
+      mix->fill_checker = gst_video_mixer_fill_checker_ayuv;
+      mix->fill_color = gst_video_mixer_fill_color_ayuv;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_ARGB:
+      mix->blend = gst_video_mixer_blend_argb;
+      mix->overlay = gst_video_mixer_overlay_argb;
+      mix->fill_checker = gst_video_mixer_fill_checker_argb;
+      mix->fill_color = gst_video_mixer_fill_color_argb;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_BGRA:
+      mix->blend = gst_video_mixer_blend_bgra;
+      mix->overlay = gst_video_mixer_overlay_bgra;
+      mix->fill_checker = gst_video_mixer_fill_checker_bgra;
+      mix->fill_color = gst_video_mixer_fill_color_bgra;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_ABGR:
+      mix->blend = gst_video_mixer_blend_abgr;
+      mix->overlay = gst_video_mixer_overlay_abgr;
+      mix->fill_checker = gst_video_mixer_fill_checker_abgr;
+      mix->fill_color = gst_video_mixer_fill_color_abgr;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_RGBA:
+      mix->blend = gst_video_mixer_blend_rgba;
+      mix->overlay = gst_video_mixer_overlay_rgba;
+      mix->fill_checker = gst_video_mixer_fill_checker_rgba;
+      mix->fill_color = gst_video_mixer_fill_color_rgba;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_Y444:
+      mix->blend = gst_video_mixer_blend_y444;
+      mix->overlay = mix->blend;
+      mix->fill_checker = gst_video_mixer_fill_checker_y444;
+      mix->fill_color = gst_video_mixer_fill_color_y444;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_Y42B:
+      mix->blend = gst_video_mixer_blend_y42b;
+      mix->overlay = mix->blend;
+      mix->fill_checker = gst_video_mixer_fill_checker_y42b;
+      mix->fill_color = gst_video_mixer_fill_color_y42b;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_YUY2:
+      mix->blend = gst_video_mixer_blend_yuy2;
+      mix->overlay = mix->blend;
+      mix->fill_checker = gst_video_mixer_fill_checker_yuy2;
+      mix->fill_color = gst_video_mixer_fill_color_yuy2;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_UYVY:
+      mix->blend = gst_video_mixer_blend_uyvy;
+      mix->overlay = mix->blend;
+      mix->fill_checker = gst_video_mixer_fill_checker_uyvy;
+      mix->fill_color = gst_video_mixer_fill_color_uyvy;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_YVYU:
+      mix->blend = gst_video_mixer_blend_yvyu;
+      mix->overlay = mix->blend;
+      mix->fill_checker = gst_video_mixer_fill_checker_yvyu;
+      mix->fill_color = gst_video_mixer_fill_color_yvyu;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_I420:
+      mix->blend = gst_video_mixer_blend_i420;
+      mix->overlay = mix->blend;
+      mix->fill_checker = gst_video_mixer_fill_checker_i420;
+      mix->fill_color = gst_video_mixer_fill_color_i420;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_YV12:
+      mix->blend = gst_video_mixer_blend_yv12;
+      mix->overlay = mix->blend;
+      mix->fill_checker = gst_video_mixer_fill_checker_yv12;
+      mix->fill_color = gst_video_mixer_fill_color_yv12;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_Y41B:
+      mix->blend = gst_video_mixer_blend_y41b;
+      mix->overlay = mix->blend;
+      mix->fill_checker = gst_video_mixer_fill_checker_y41b;
+      mix->fill_color = gst_video_mixer_fill_color_y41b;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_RGB:
+      mix->blend = gst_video_mixer_blend_rgb;
+      mix->overlay = mix->blend;
+      mix->fill_checker = gst_video_mixer_fill_checker_rgb;
+      mix->fill_color = gst_video_mixer_fill_color_rgb;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_BGR:
+      mix->blend = gst_video_mixer_blend_bgr;
+      mix->overlay = mix->blend;
+      mix->fill_checker = gst_video_mixer_fill_checker_bgr;
+      mix->fill_color = gst_video_mixer_fill_color_bgr;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_xRGB:
+      mix->blend = gst_video_mixer_blend_xrgb;
+      mix->overlay = mix->blend;
+      mix->fill_checker = gst_video_mixer_fill_checker_xrgb;
+      mix->fill_color = gst_video_mixer_fill_color_xrgb;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_xBGR:
+      mix->blend = gst_video_mixer_blend_xbgr;
+      mix->overlay = mix->blend;
+      mix->fill_checker = gst_video_mixer_fill_checker_xbgr;
+      mix->fill_color = gst_video_mixer_fill_color_xbgr;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_RGBx:
+      mix->blend = gst_video_mixer_blend_rgbx;
+      mix->overlay = mix->blend;
+      mix->fill_checker = gst_video_mixer_fill_checker_rgbx;
+      mix->fill_color = gst_video_mixer_fill_color_rgbx;
+      ret = TRUE;
+      break;
+    case GST_VIDEO_FORMAT_BGRx:
+      mix->blend = gst_video_mixer_blend_bgrx;
+      mix->overlay = mix->blend;
+      mix->fill_checker = gst_video_mixer_fill_checker_bgrx;
+      mix->fill_color = gst_video_mixer_fill_color_bgrx;
+      ret = TRUE;
+      break;
+    default:
+      break;
+  }
+  GST_VIDEO_MIXER2_UNLOCK (mix);
+
+done:
+  gst_object_unref (mix);
+
+  return ret;
+}
+
+static GstFlowReturn
+gst_videomixer2_sink_prepare_buffer (GstCollectPads2 * pads,
+    GstCollectData2 * data, GstBuffer * buf, GstVideoMixer2 * mix)
+{
+  GstVideoMixer2Pad *pad = GST_VIDEO_MIXER2_PAD (data->pad);
+  GstVideoMixer2Collect *mixcol = pad->mixcol;
+  GstClockTime start_time, end_time;
+
+  start_time = GST_BUFFER_TIMESTAMP (buf);
+  if (start_time == -1) {
+    GST_ERROR_OBJECT (pad, "Timestamped buffers required!");
+    return GST_FLOW_ERROR;
+  }
+
+  end_time = GST_BUFFER_DURATION (buf);
+  if (end_time == -1)
+    end_time = gst_util_uint64_scale_int (GST_SECOND, pad->fps_d, pad->fps_n);
+  if (end_time == -1)
+    return GST_FLOW_OK;
+
+  start_time = MAX (start_time, mixcol->collect.segment.start);
+  start_time =
+      gst_segment_to_running_time (&mixcol->collect.segment,
+      GST_FORMAT_TIME, start_time);
+
+  end_time += GST_BUFFER_TIMESTAMP (buf);
+  if (mixcol->collect.segment.stop != -1)
+    end_time = MIN (end_time, mixcol->collect.segment.stop);
+  end_time =
+      gst_segment_to_running_time (&mixcol->collect.segment,
+      GST_FORMAT_TIME, end_time);
+
+  /* Convert to the output segment rate */
+  if (mix->segment.abs_rate != 1.0) {
+    start_time *= mix->segment.abs_rate;
+    end_time *= mix->segment.abs_rate;
+  }
+
+  if (mixcol->buffer != NULL && end_time < mixcol->end_time) {
+    return GST_COLLECT_PADS2_FLOW_DROP;
+  }
+
+  return GST_FLOW_OK;
+}
+
+static gboolean
+gst_videomixer2_sink_event (GstCollectPads2 * pads, GstCollectData2 * cdata,
+    GstEvent * event, GstVideoMixer2 * mix)
+{
+  GstVideoMixer2Pad *pad = GST_VIDEO_MIXER2_PAD (cdata->pad);
+  gboolean ret = TRUE;
+
+  GST_DEBUG_OBJECT (pad, "Got %s event on pad %s:%s",
+      GST_EVENT_TYPE_NAME (event), GST_DEBUG_PAD_NAME (pad));
+
+  /* return FALSE => event will be forwarded */
+  switch (GST_EVENT_TYPE (event)) {
+    case GST_EVENT_NEWSEGMENT:{
+      GstFormat fmt;
+      gst_event_parse_new_segment (event, NULL, NULL, &fmt, NULL, NULL, NULL);
+
+      g_assert (fmt == GST_FORMAT_TIME);
+      /* eat NEWSEGMENT events, collectpads2 unrefs the event */
+      ret = FALSE;
+      break;
+    }
+    case GST_EVENT_FLUSH_STOP:
+      mix->newseg_pending = TRUE;
+      mix->flush_stop_pending = FALSE;
+      gst_videomixer2_reset_qos (mix);
+      gst_buffer_replace (&pad->mixcol->buffer, NULL);
+      pad->mixcol->start_time = -1;
+      pad->mixcol->end_time = -1;
+
+      gst_segment_init (&mix->segment, GST_FORMAT_TIME);
+      mix->segment.last_stop = -1;
+      mix->ts_offset = 0;
+      mix->nframes = 0;
+
+      gst_pad_push_event (mix->srcpad, event);
+      break;
+    default:
+      gst_pad_push_event (mix->srcpad, event);
+      break;
+  }
+
+  return ret;
+}
+
+static gboolean
+forward_event_func (GstPad * pad, GValue * ret, GstEvent * event)
+{
+  gst_event_ref (event);
+  GST_LOG_OBJECT (pad, "About to send event %s", GST_EVENT_TYPE_NAME (event));
+  if (!gst_pad_push_event (pad, event)) {
+    g_value_set_boolean (ret, FALSE);
+    GST_WARNING_OBJECT (pad, "Sending event  %p (%s) failed.",
+        event, GST_EVENT_TYPE_NAME (event));
+  } else {
+    GST_LOG_OBJECT (pad, "Sent event  %p (%s).",
+        event, GST_EVENT_TYPE_NAME (event));
+  }
+  gst_object_unref (pad);
+  return TRUE;
+}
+
+static gboolean
+gst_videomixer2_push_sink_event (GstVideoMixer2 * mix, GstEvent * event)
+{
+  GstIterator *it;
+  GValue vret = { 0 };
+
+  GST_LOG_OBJECT (mix, "Forwarding event %p (%s)", event,
+      GST_EVENT_TYPE_NAME (event));
+
+  g_value_init (&vret, G_TYPE_BOOLEAN);
+  g_value_set_boolean (&vret, TRUE);
+  it = gst_element_iterate_sink_pads (GST_ELEMENT_CAST (mix));
+  gst_iterator_fold (it, (GstIteratorFoldFunction) forward_event_func, &vret,
+      event);
+  gst_iterator_free (it);
+  gst_event_unref (event);
+
+  return g_value_get_boolean (&vret);
+}
+
+/* GstElement vmethods */
+static GstStateChangeReturn
+gst_videomixer2_change_state (GstElement * element, GstStateChange transition)
+{
+  GstVideoMixer2 *mix = GST_VIDEO_MIXER2 (element);
+  GstStateChangeReturn ret;
+
+  switch (transition) {
+    case GST_STATE_CHANGE_READY_TO_PAUSED:
+      GST_LOG_OBJECT (mix, "starting collectpads");
+      gst_collect_pads2_start (mix->collect);
+      break;
+    case GST_STATE_CHANGE_PAUSED_TO_READY:
+      GST_LOG_OBJECT (mix, "stopping collectpads");
+      gst_collect_pads2_stop (mix->collect);
+      break;
+    default:
+      break;
+  }
+
+  ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
+
+  switch (transition) {
+    case GST_STATE_CHANGE_PAUSED_TO_READY:
+      gst_videomixer2_reset (mix);
+      break;
+    default:
+      break;
+  }
+
+  return ret;
+}
+
+static GstPad *
+gst_videomixer2_request_new_pad (GstElement * element,
+    GstPadTemplate * templ, const gchar * req_name)
+{
+  GstVideoMixer2 *mix;
+  GstVideoMixer2Pad *mixpad;
+  GstElementClass *klass = GST_ELEMENT_GET_CLASS (element);
+
+  mix = GST_VIDEO_MIXER2 (element);
+
+  if (templ == gst_element_class_get_pad_template (klass, "sink_%d")) {
+    gint serial = 0;
+    gchar *name = NULL;
+    GstVideoMixer2Collect *mixcol = NULL;
+
+    GST_VIDEO_MIXER2_LOCK (mix);
+    if (req_name == NULL || strlen (req_name) < 6
+        || !g_str_has_prefix (req_name, "sink_")) {
+      /* no name given when requesting the pad, use next available int */
+      serial = mix->next_sinkpad++;
+    } else {
+      /* parse serial number from requested padname */
+      serial = g_ascii_strtoull (&req_name[5], NULL, 10);
+      if (serial >= mix->next_sinkpad)
+        mix->next_sinkpad = serial + 1;
+    }
+    /* create new pad with the name */
+    name = g_strdup_printf ("sink_%d", serial);
+    mixpad = g_object_new (GST_TYPE_VIDEO_MIXER2_PAD, "name", name, "direction",
+        templ->direction, "template", templ, NULL);
+    g_free (name);
+
+    mixpad->zorder = mix->numpads;
+    mixpad->xpos = DEFAULT_PAD_XPOS;
+    mixpad->ypos = DEFAULT_PAD_YPOS;
+    mixpad->alpha = DEFAULT_PAD_ALPHA;
+
+    mixcol = (GstVideoMixer2Collect *)
+        gst_collect_pads2_add_pad_full (mix->collect, GST_PAD (mixpad),
+        sizeof (GstVideoMixer2Collect),
+        (GstCollectData2DestroyNotify) gst_videomixer2_collect_free, TRUE);
+
+    /* Keep track of each other */
+    mixcol->mixpad = mixpad;
+    mixpad->mixcol = mixcol;
+
+    mixcol->start_time = -1;
+    mixcol->end_time = -1;
+
+    /* Keep an internal list of mixpads for zordering */
+    mix->sinkpads = g_slist_append (mix->sinkpads, mixpad);
+    mix->numpads++;
+    GST_VIDEO_MIXER2_UNLOCK (mix);
+  } else {
+    return NULL;
+  }
+
+  GST_DEBUG_OBJECT (element, "Adding pad %s", GST_PAD_NAME (mixpad));
+
+  /* add the pad to the element */
+  gst_element_add_pad (element, GST_PAD (mixpad));
+  gst_child_proxy_child_added (GST_OBJECT (mix), GST_OBJECT (mixpad));
+
+  return GST_PAD (mixpad);
+}
+
+static void
+gst_videomixer2_release_pad (GstElement * element, GstPad * pad)
+{
+  GstVideoMixer2 *mix = NULL;
+  GstVideoMixer2Pad *mixpad;
+  gboolean update_caps;
+
+  mix = GST_VIDEO_MIXER2 (element);
+
+  GST_VIDEO_MIXER2_LOCK (mix);
+  if (G_UNLIKELY (g_slist_find (mix->sinkpads, pad) == NULL)) {
+    g_warning ("Unknown pad %s", GST_PAD_NAME (pad));
+    goto error;
+  }
+
+  mixpad = GST_VIDEO_MIXER2_PAD (pad);
+
+  mix->sinkpads = g_slist_remove (mix->sinkpads, pad);
+  gst_child_proxy_child_removed (GST_OBJECT (mix), GST_OBJECT (mixpad));
+  mix->numpads--;
+
+  update_caps = mix->format != GST_VIDEO_FORMAT_UNKNOWN;
+  GST_VIDEO_MIXER2_UNLOCK (mix);
+
+  gst_collect_pads2_remove_pad (mix->collect, pad);
+
+  if (update_caps)
+    gst_videomixer2_update_src_caps (mix);
+
+  gst_element_remove_pad (element, pad);
+  return;
+error:
+  GST_VIDEO_MIXER2_UNLOCK (mix);
+}
+
+/* GObject vmethods */
+static void
+gst_videomixer2_finalize (GObject * o)
+{
+  GstVideoMixer2 *mix = GST_VIDEO_MIXER2 (o);
+
+  gst_object_unref (mix->collect);
+  g_mutex_free (mix->lock);
+
+  G_OBJECT_CLASS (parent_class)->finalize (o);
+}
+
+static void
+gst_videomixer2_get_property (GObject * object,
+    guint prop_id, GValue * value, GParamSpec * pspec)
+{
+  GstVideoMixer2 *mix = GST_VIDEO_MIXER2 (object);
+
+  switch (prop_id) {
+    case PROP_BACKGROUND:
+      g_value_set_enum (value, mix->background);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+gst_videomixer2_set_property (GObject * object,
+    guint prop_id, const GValue * value, GParamSpec * pspec)
+{
+  GstVideoMixer2 *mix = GST_VIDEO_MIXER2 (object);
+
+  switch (prop_id) {
+    case PROP_BACKGROUND:
+      mix->background = g_value_get_enum (value);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+/* GstChildProxy implementation */
+static GstObject *
+gst_videomixer2_child_proxy_get_child_by_index (GstChildProxy * child_proxy,
+    guint index)
+{
+  GstVideoMixer2 *mix = GST_VIDEO_MIXER2 (child_proxy);
+  GstObject *obj;
+
+  GST_VIDEO_MIXER2_LOCK (mix);
+  if ((obj = g_slist_nth_data (mix->sinkpads, index)))
+    gst_object_ref (obj);
+  GST_VIDEO_MIXER2_UNLOCK (mix);
+  return obj;
+}
+
+static guint
+gst_videomixer2_child_proxy_get_children_count (GstChildProxy * child_proxy)
+{
+  guint count = 0;
+  GstVideoMixer2 *mix = GST_VIDEO_MIXER2 (child_proxy);
+
+  GST_VIDEO_MIXER2_LOCK (mix);
+  count = mix->numpads;
+  GST_VIDEO_MIXER2_UNLOCK (mix);
+  GST_INFO_OBJECT (mix, "Children Count: %d", count);
+  return count;
+}
+
+static void
+gst_videomixer2_child_proxy_init (gpointer g_iface, gpointer iface_data)
+{
+  GstChildProxyInterface *iface = g_iface;
+
+  GST_INFO ("intializing child proxy interface");
+  iface->get_child_by_index = gst_videomixer2_child_proxy_get_child_by_index;
+  iface->get_children_count = gst_videomixer2_child_proxy_get_children_count;
+}
+
+/* GObject boilerplate */
+static void
+gst_videomixer2_base_init (gpointer g_class)
+{
+  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
+
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&src_factory));
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&sink_factory));
+
+  gst_element_class_set_details_simple (element_class, "Video mixer 2",
+      "Filter/Editor/Video",
+      "Mix multiple video streams", "Wim Taymans <wim@fluendo.com>, "
+      "Sebastian Dröge <sebastian.droege@collabora.co.uk>");
+}
+
+static void
+gst_videomixer2_class_init (GstVideoMixer2Class * klass)
+{
+  GObjectClass *gobject_class = (GObjectClass *) klass;
+  GstElementClass *gstelement_class = (GstElementClass *) klass;
+
+  gobject_class->finalize = gst_videomixer2_finalize;
+
+  gobject_class->get_property = gst_videomixer2_get_property;
+  gobject_class->set_property = gst_videomixer2_set_property;
+
+  g_object_class_install_property (gobject_class, PROP_BACKGROUND,
+      g_param_spec_enum ("background", "Background", "Background type",
+          GST_TYPE_VIDEO_MIXER2_BACKGROUND,
+          DEFAULT_BACKGROUND, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+  gstelement_class->request_new_pad =
+      GST_DEBUG_FUNCPTR (gst_videomixer2_request_new_pad);
+  gstelement_class->release_pad =
+      GST_DEBUG_FUNCPTR (gst_videomixer2_release_pad);
+  gstelement_class->change_state =
+      GST_DEBUG_FUNCPTR (gst_videomixer2_change_state);
+
+  /* Register the pad class */
+  g_type_class_ref (GST_TYPE_VIDEO_MIXER2_PAD);
+}
+
+static void
+gst_videomixer2_init (GstVideoMixer2 * mix, GstVideoMixer2Class * g_class)
+{
+  GstElementClass *klass = GST_ELEMENT_GET_CLASS (mix);
+
+  mix->srcpad =
+      gst_pad_new_from_template (gst_element_class_get_pad_template (klass,
+          "src"), "src");
+  gst_pad_set_getcaps_function (GST_PAD (mix->srcpad),
+      GST_DEBUG_FUNCPTR (gst_videomixer2_src_getcaps));
+  gst_pad_set_setcaps_function (GST_PAD (mix->srcpad),
+      GST_DEBUG_FUNCPTR (gst_videomixer2_src_setcaps));
+  gst_pad_set_query_function (GST_PAD (mix->srcpad),
+      GST_DEBUG_FUNCPTR (gst_videomixer2_src_query));
+  gst_pad_set_event_function (GST_PAD (mix->srcpad),
+      GST_DEBUG_FUNCPTR (gst_videomixer2_src_event));
+  gst_element_add_pad (GST_ELEMENT (mix), mix->srcpad);
+
+  mix->collect = gst_collect_pads2_new ();
+  mix->background = DEFAULT_BACKGROUND;
+
+  gst_collect_pads2_set_function (mix->collect,
+      (GstCollectPads2Function) GST_DEBUG_FUNCPTR (gst_videomixer2_collected),
+      mix);
+  gst_collect_pads2_set_event_function (mix->collect,
+      (GstCollectPads2EventFunction) gst_videomixer2_sink_event, mix);
+  gst_collect_pads2_set_prepare_buffer_function (mix->collect,
+      (GstCollectPads2BufferFunction) gst_videomixer2_sink_prepare_buffer, mix);
+
+  mix->lock = g_mutex_new ();
+  /* initialize variables */
+  gst_videomixer2_reset (mix);
+}
+
+/* Element registration */
+gboolean
+gst_videomixer2_register (GstPlugin * plugin)
+{
+  GST_DEBUG_CATEGORY_INIT (gst_videomixer2_debug, "videomixer2", 0,
+      "video mixer 2");
+
+  return gst_element_register (plugin, "videomixer2", GST_RANK_SECONDARY,
+      GST_TYPE_VIDEO_MIXER2);
+}