Added videosignal plugin with two plugins to analyse video frames.

Original commit message from CVS:
* configure.ac:
* docs/plugins/Makefile.am:
* docs/plugins/gst-plugins-bad-plugins-docs.sgml:
* docs/plugins/gst-plugins-bad-plugins-sections.txt:
* docs/plugins/inspect/plugin-videosignal.xml:
* gst/videosignal/Makefile.am:
* gst/videosignal/gstvideoanalyse.c: (gst_video_analyse_set_caps),
(gst_video_analyse_post_message), (gst_video_analyse_420),
(gst_video_analyse_transform_ip), (gst_video_analyse_set_property),
(gst_video_analyse_get_property), (gst_video_analyse_base_init),
(gst_video_analyse_class_init), (gst_video_analyse_init),
(gst_video_analyse_get_type):
* gst/videosignal/gstvideoanalyse.h:
* gst/videosignal/gstvideodetect.c: (gst_video_detect_set_caps),
(gst_video_detect_post_message),
(gst_video_detect_calc_brightness), (gst_video_detect_420),
(gst_video_detect_transform_ip), (gst_video_detect_set_property),
(gst_video_detect_get_property), (gst_video_detect_base_init),
(gst_video_detect_class_init), (gst_video_detect_init),
(gst_video_detect_get_type):
* gst/videosignal/gstvideodetect.h:
* gst/videosignal/gstvideosignal.c: (plugin_init):
* gst/videosignal/gstvideosignal.h:
Added videosignal plugin with two plugins to analyse video frames.
Added videoanalyse to report about brightness and variance in video
frames.
Added videodetect to detect predefined patterns in a video signal.

7 files changed, 1105 insertions, 0 deletions

diff --git a/gst/videosignal/Makefile.am b/gst/videosignal/Makefile.am
new file mode 100644
index 00000000..1877c4c0
--- /dev/null
+++ b/gst/videosignal/Makefile.am
@@ -0,0 +1,12 @@
+plugin_LTLIBRARIES = libgstvideosignal.la 
+
+noinst_HEADERS = gstvideoanalyse.h gstvideodetect.h
+
+libgstvideosignal_la_SOURCES = gstvideosignal.c   \
+                               gstvideoanalyse.c  \
+                               gstvideodetect.c
+
+libgstvideosignal_la_CFLAGS = $(GST_CFLAGS) $(GST_BASE_CFLAGS) \
+			    $(GST_PLUGINS_BASE_CFLAGS)
+libgstvideosignal_la_LIBADD = $(GST_PLUGINS_BASE_LIBS) -lgstvideo-@GST_MAJORMINOR@ $(GST_BASE_LIBS) $(GST_LIBS)
+libgstvideosignal_la_LDFLAGS = $(GST_PLUGIN_LDFLAGS)
diff --git a/gst/videosignal/gstvideoanalyse.c b/gst/videosignal/gstvideoanalyse.c
new file mode 100644
index 00000000..d0cdf70c
--- /dev/null
+++ b/gst/videosignal/gstvideoanalyse.c
@@ -0,0 +1,353 @@
+/* GStreamer
+ * Copyright (C) <2006> Wim Taymans <wim@fluendo.com>
+ *
+ * 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-videoanalyse
+ * @short_description: Analyse and report about the video frame
+ *
+ * <refsect2>
+ * <para>
+ * This plugin analyses every video frame and if the <link
+ * linkend="GstVideoAnalyse--message">message property</link> is #TRUE, posts an element
+ * message with video statistics called <classname>&quot;GstVideoAnalyse&quot;</classname>.
+ * The message's structure contains these fields:
+ * <itemizedlist>
+ * <listitem>
+ *   <para>
+ *   #GstClockTime
+ *   <classname>&quot;timestamp&quot;</classname>:
+ *   the timestamp of the buffer that triggered the message.
+ *   </para>
+ * </listitem>
+ * <listitem>
+ *   <para>
+ *   #GstClockTime
+ *   <classname>&quot;stream-time&quot;</classname>:
+ *   the stream time of the buffer.
+ *   </para>
+ * </listitem>
+ * <listitem>
+ *   <para>
+ *   #GstClockTime
+ *   <classname>&quot;running-time&quot;</classname>:
+ *   the running_time of the buffer.
+ *   </para>
+ * </listitem>
+ * <listitem>
+ *   <para>
+ *   #GstClockTime
+ *   <classname>&quot;duration&quot;</classname>:
+ *   the duration of the buffer.
+ *   </para>
+ * </listitem>
+ * <listitem>
+ *   <para>
+ *   #gdouble
+ *   <classname>&quot;brightness&quot;</classname>:
+ *   the average brightness of the frame.
+ *   </para>
+ * </listitem>
+ * <listitem>
+ *   <para>
+ *   #gdouble
+ *   <classname>&quot;brightness-variance&quot;</classname>:
+ *   the brightness variance of the frame.
+ *   </para>
+ * </listitem>
+  * </itemizedlist>
+ * </para>
+ * <title>Example launch line</title>
+ * <para>
+ * <programlisting>
+ * gst-launch -m videotestsrc ! videoanalyse ! ffmpegcolorspace ! ximagesink
+ * </programlisting>
+ * This pipeline emits messages to the console for each frame that has been analysed. 
+ * </para>
+ * </refsect2>
+ *
+ * Last reviewed on 2007-05-30 (0.10.5)
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "gstvideoanalyse.h"
+
+#include <string.h>
+#include <math.h>
+
+#include <gst/video/video.h>
+
+/* GstVideoAnalyse signals and args */
+
+#define DEFAULT_MESSAGE		TRUE
+
+enum
+{
+  PROP_0,
+  PROP_MESSAGE
+};
+
+GST_DEBUG_CATEGORY_STATIC (video_analyse_debug);
+#define GST_CAT_DEFAULT video_analyse_debug
+
+static const GstElementDetails video_analyse_details =
+GST_ELEMENT_DETAILS ("Video analyser",
+    "Filter/Effect/Video",
+    "Analyse video signal",
+    "Wim Taymans <wim@fluendo.com>");
+
+static GstStaticPadTemplate gst_video_analyse_src_template =
+GST_STATIC_PAD_TEMPLATE ("src",
+    GST_PAD_SRC,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("{ I420, YV12 }"))
+    );
+
+static GstStaticPadTemplate gst_video_analyse_sink_template =
+GST_STATIC_PAD_TEMPLATE ("sink",
+    GST_PAD_SINK,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("{ I420, YV12 }"))
+    );
+
+static GstVideoFilterClass *parent_class = NULL;
+
+static gboolean
+gst_video_analyse_set_caps (GstBaseTransform * btrans, GstCaps * incaps,
+    GstCaps * outcaps)
+{
+  GstVideoAnalyse *vf;
+  GstStructure *in_s;
+  gboolean ret;
+
+  vf = GST_VIDEO_ANALYSE (btrans);
+
+  in_s = gst_caps_get_structure (incaps, 0);
+
+  ret = gst_structure_get_int (in_s, "width", &vf->width);
+  ret &= gst_structure_get_int (in_s, "height", &vf->height);
+
+  return ret;
+}
+
+/* Useful macros */
+#define GST_VIDEO_I420_Y_ROWSTRIDE(width) (GST_ROUND_UP_4(width))
+#define GST_VIDEO_I420_U_ROWSTRIDE(width) (GST_ROUND_UP_8(width)/2)
+#define GST_VIDEO_I420_V_ROWSTRIDE(width) ((GST_ROUND_UP_8(GST_VIDEO_I420_Y_ROWSTRIDE(width)))/2)
+
+#define GST_VIDEO_I420_Y_OFFSET(w,h) (0)
+#define GST_VIDEO_I420_U_OFFSET(w,h) (GST_VIDEO_I420_Y_OFFSET(w,h)+(GST_VIDEO_I420_Y_ROWSTRIDE(w)*GST_ROUND_UP_2(h)))
+#define GST_VIDEO_I420_V_OFFSET(w,h) (GST_VIDEO_I420_U_OFFSET(w,h)+(GST_VIDEO_I420_U_ROWSTRIDE(w)*GST_ROUND_UP_2(h)/2))
+
+#define GST_VIDEO_I420_SIZE(w,h)     (GST_VIDEO_I420_V_OFFSET(w,h)+(GST_VIDEO_I420_V_ROWSTRIDE(w)*GST_ROUND_UP_2(h)/2))
+
+static void
+gst_video_analyse_post_message (GstVideoAnalyse * videoanalyse,
+    GstBuffer * buffer)
+{
+  GstBaseTransform *trans;
+  GstMessage *m;
+  guint64 duration, timestamp, running_time, stream_time;
+
+  trans = GST_BASE_TRANSFORM_CAST (videoanalyse);
+
+  /* get timestamps */
+  timestamp = GST_BUFFER_TIMESTAMP (buffer);
+  duration = GST_BUFFER_DURATION (buffer);
+  running_time = gst_segment_to_running_time (&trans->segment, GST_FORMAT_TIME,
+      timestamp);
+  stream_time = gst_segment_to_stream_time (&trans->segment, GST_FORMAT_TIME,
+      timestamp);
+
+  m = gst_message_new_element (GST_OBJECT_CAST (videoanalyse),
+      gst_structure_new ("GstVideoAnalyse",
+          "timestamp", G_TYPE_UINT64, timestamp,
+          "stream-time", G_TYPE_UINT64, stream_time,
+          "running-time", G_TYPE_UINT64, running_time,
+          "duration", G_TYPE_UINT64, duration,
+          "brightness", G_TYPE_DOUBLE, videoanalyse->brightness,
+          "brightness-variance", G_TYPE_DOUBLE, videoanalyse->brightness_var,
+          NULL));
+
+  gst_element_post_message (GST_ELEMENT_CAST (videoanalyse), m);
+}
+
+static void
+gst_video_analyse_420 (GstVideoAnalyse * videoanalyse, guint8 * data,
+    gint width, gint height)
+{
+  guint64 sum;
+  gint avg, diff;
+  gint i, j;
+  guint8 *d;
+
+  d = data;
+  sum = 0;
+  /* do brightness as average of pixel brightness in 0.0 to 1.0 */
+  for (i = 0; i < height; i++) {
+    for (j = 0; j < width; j++) {
+      sum += data[j];
+    }
+    d += GST_VIDEO_I420_Y_ROWSTRIDE (width);
+  }
+  avg = sum / (width * height);
+  videoanalyse->brightness = sum / (255.0 * width * height);
+
+  d = data;
+  sum = 0;
+  /* do variance */
+  for (i = 0; i < height; i++) {
+    for (j = 0; j < width; j++) {
+      diff = (avg - d[j]);
+      sum += diff * diff;
+    }
+    d += GST_VIDEO_I420_Y_ROWSTRIDE (width);
+  }
+  videoanalyse->brightness_var = sum / (255.0 * 255.0 * width * height);
+}
+
+static GstFlowReturn
+gst_video_analyse_transform_ip (GstBaseTransform * trans, GstBuffer * buf)
+{
+  GstVideoAnalyse *videoanalyse;
+  GstFlowReturn ret = GST_FLOW_OK;
+  guint8 *data;
+
+  videoanalyse = GST_VIDEO_ANALYSE (trans);
+
+  data = GST_BUFFER_DATA (buf);
+
+  gst_video_analyse_420 (videoanalyse, data, videoanalyse->width,
+      videoanalyse->height);
+
+  if (videoanalyse->message)
+    gst_video_analyse_post_message (videoanalyse, buf);
+
+  return ret;
+}
+
+static void
+gst_video_analyse_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec)
+{
+  GstVideoAnalyse *videoanalyse;
+
+  videoanalyse = GST_VIDEO_ANALYSE (object);
+
+  switch (prop_id) {
+    case PROP_MESSAGE:
+      videoanalyse->message = g_value_get_boolean (value);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+gst_video_analyse_get_property (GObject * object, guint prop_id, GValue * value,
+    GParamSpec * pspec)
+{
+  GstVideoAnalyse *videoanalyse;
+
+  videoanalyse = GST_VIDEO_ANALYSE (object);
+
+  switch (prop_id) {
+    case PROP_MESSAGE:
+      g_value_set_boolean (value, videoanalyse->message);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+gst_video_analyse_base_init (gpointer g_class)
+{
+  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
+
+  gst_element_class_set_details (element_class, &video_analyse_details);
+
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&gst_video_analyse_sink_template));
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&gst_video_analyse_src_template));
+}
+
+static void
+gst_video_analyse_class_init (gpointer klass, gpointer class_data)
+{
+  GObjectClass *gobject_class;
+  GstBaseTransformClass *trans_class;
+
+  gobject_class = (GObjectClass *) klass;
+  trans_class = (GstBaseTransformClass *) klass;
+
+  parent_class = g_type_class_peek_parent (klass);
+
+  gobject_class->set_property = gst_video_analyse_set_property;
+  gobject_class->get_property = gst_video_analyse_get_property;
+
+  g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_MESSAGE,
+      g_param_spec_boolean ("message", "Message",
+          "Post statics messages",
+          DEFAULT_MESSAGE, G_PARAM_READWRITE | G_PARAM_CONSTRUCT));
+
+  trans_class->set_caps = GST_DEBUG_FUNCPTR (gst_video_analyse_set_caps);
+  trans_class->transform_ip =
+      GST_DEBUG_FUNCPTR (gst_video_analyse_transform_ip);
+  trans_class->passthrough_on_same_caps = TRUE;
+}
+
+static void
+gst_video_analyse_init (GTypeInstance * instance, gpointer g_class)
+{
+  GstVideoAnalyse *videoanalyse;
+
+  videoanalyse = GST_VIDEO_ANALYSE (instance);
+
+  GST_DEBUG_OBJECT (videoanalyse, "gst_video_analyse_init");
+}
+
+GType
+gst_video_analyse_get_type (void)
+{
+  static GType video_analyse_type = 0;
+
+  if (!video_analyse_type) {
+    static const GTypeInfo video_analyse_info = {
+      sizeof (GstVideoAnalyseClass),
+      gst_video_analyse_base_init,
+      NULL,
+      gst_video_analyse_class_init,
+      NULL,
+      NULL,
+      sizeof (GstVideoAnalyse),
+      0,
+      gst_video_analyse_init,
+    };
+
+    video_analyse_type = g_type_register_static (GST_TYPE_VIDEO_FILTER,
+        "GstVideoAnalyse", &video_analyse_info, 0);
+  }
+  return video_analyse_type;
+}
diff --git a/gst/videosignal/gstvideoanalyse.h b/gst/videosignal/gstvideoanalyse.h
new file mode 100644
index 00000000..221f63ba
--- /dev/null
+++ b/gst/videosignal/gstvideoanalyse.h
@@ -0,0 +1,67 @@
+/* GStreamer
+ * Copyright (C) <2006> Wim Taymans <wim@fluendo.com>
+ *
+ * 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.
+ */
+
+#ifndef __GST_VIDEO_ANALYSE_H__
+#define __GST_VIDEO_ANALYSE_H__
+
+#include <gst/video/gstvideofilter.h>
+
+G_BEGIN_DECLS
+
+#define GST_TYPE_VIDEO_ANALYSE \
+  (gst_video_analyse_get_type())
+#define GST_VIDEO_ANALYSE(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_VIDEO_ANALYSE,GstVideoAnalyse))
+#define GST_VIDEO_ANALYSE_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_VIDEO_ANALYSE,GstVideoAnalyseClass))
+#define GST_IS_VIDEO_ANALYSE(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_VIDEO_ANALYSE))
+#define GST_IS_VIDEO_ANALYSE_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_VIDEO_ANALYSE))
+
+typedef struct _GstVideoAnalyse GstVideoAnalyse;
+typedef struct _GstVideoAnalyseClass GstVideoAnalyseClass;
+
+/**
+ * GstVideoAnalyse:
+ *
+ * Opaque datastructure.
+ */
+struct _GstVideoAnalyse {
+  GstVideoFilter videofilter;
+  
+  gint width, height;
+
+  gboolean message;
+
+  gdouble brightness;
+  gdouble brightness_var;
+
+  guint64 interval;
+};
+
+struct _GstVideoAnalyseClass {
+  GstVideoFilterClass parent_class;
+};
+
+GType gst_video_analyse_get_type (void);
+
+G_END_DECLS
+
+#endif /* __GST_VIDEO_ANALYSE_H__ */
diff --git a/gst/videosignal/gstvideodetect.c b/gst/videosignal/gstvideodetect.c
new file mode 100644
index 00000000..54d0dd77
--- /dev/null
+++ b/gst/videosignal/gstvideodetect.c
@@ -0,0 +1,493 @@
+/* GStreamer
+ * Copyright (C) <2007> Wim Taymans <wim@fluendo.com>
+ *
+ * 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-videodetect
+ * @short_description: Detect a pattern in a video signal
+ *
+ * <refsect2>
+ * <para>
+ * This plugin detects ::pattern-count squares in the bottom left corner of
+ * the video frames. The squares have a width and height of respectively
+ * ::pattern-width and ::patern-height. Even squares must be black and odd
+ * squares must be white.
+ * </para>
+ * <para>
+ * When the pattern has been found, ::pattern-data-count squares after the
+ * pattern squares are read as a bitarray. White squares represent a 1 bit and
+ * black squares a 0 bit. The bitarray will will included in the element message
+ * that is posted (see below).
+ * </para>
+ * <para>
+ * After the pattern has been found and the data pattern has been read, an
+ * element message called <classname>&quot;GstVideoDetect&quot;</classname> will
+ * be posted on the bus. If the pattern is no longer found in the frame, the
+ * same element message is posted with the have-pattern field set to #FALSE.
+ * The message is only posted if the <link linkend="GstVideoDetect--message">message
+ * property</link> is #TRUE.
+ * </para>
+ * <para>
+ * The message's structure contains these fields:
+ * <itemizedlist>
+ * <listitem>
+ *   <para>
+ *   #gboolean
+ *   <classname>&quot;have-pattern&quot;</classname>:
+ *   if the pattern was found. This field will be set to #TRUE for as long as
+ *   the pattern was found in the frame and set to FALSE for the first frame
+ *   that does not contain the pattern anymore.
+ *   </para>
+ * </listitem>
+ * <listitem>
+ *   <para>
+ *   #GstClockTime
+ *   <classname>&quot;timestamp&quot;</classname>:
+ *   the timestamp of the buffer that triggered the message.
+ *   </para>
+ * </listitem>
+ * <listitem>
+ *   <para>
+ *   #GstClockTime
+ *   <classname>&quot;stream-time&quot;</classname>:
+ *   the stream time of the buffer.
+ *   </para>
+ * </listitem>
+ * <listitem>
+ *   <para>
+ *   #GstClockTime
+ *   <classname>&quot;running-time&quot;</classname>:
+ *   the running_time of the buffer.
+ *   </para>
+ * </listitem>
+ * <listitem>
+ *   <para>
+ *   #GstClockTime
+ *   <classname>&quot;duration&quot;</classname>:
+ *   the duration of the buffer.
+ *   </para>
+ * </listitem>
+ * <listitem>
+ *   <para>
+ *   #guint
+ *   <classname>&quot;data&quot;</classname>:
+ *   the data-pattern found after the pattern or 0 when have-signal is #FALSE.
+ *   </para>
+ * </listitem>
+ * </itemizedlist>
+ * </para>
+ * <title>Example launch line</title>
+ * <para>
+ * <programlisting>
+ * gst-launch videotestsrc ! videodetect ! ffmpegcolorspace ! ximagesink
+ * </programlisting>
+ * </para>
+ * </refsect2>
+ *
+ * Last reviewed on 2007-05-30 (0.10.5)
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "gstvideodetect.h"
+
+#include <string.h>
+#include <math.h>
+
+#include <gst/video/video.h>
+
+/* GstVideoDetect signals and args */
+
+#define DEFAULT_MESSAGE              TRUE
+#define DEFAULT_PATTERN_WIDTH        4
+#define DEFAULT_PATTERN_HEIGHT       16
+#define DEFAULT_PATTERN_COUNT        4
+#define DEFAULT_PATTERN_DATA_COUNT   5
+#define DEFAULT_PATTERN_SENSITIVITY  0.2
+
+enum
+{
+  PROP_0,
+  PROP_MESSAGE,
+  PROP_PATTERN_WIDTH,
+  PROP_PATTERN_HEIGHT,
+  PROP_PATTERN_COUNT,
+  PROP_PATTERN_DATA_COUNT,
+  PROP_PATTERN_SENSITIVITY
+};
+
+GST_DEBUG_CATEGORY_STATIC (video_detect_debug);
+#define GST_CAT_DEFAULT video_detect_debug
+
+static const GstElementDetails video_detect_details =
+GST_ELEMENT_DETAILS ("Video detecter",
+    "Filter/Effect/Video",
+    "Detect patterns in a video signal",
+    "Wim Taymans <wim@fluendo.com>");
+
+static GstStaticPadTemplate gst_video_detect_src_template =
+GST_STATIC_PAD_TEMPLATE ("src",
+    GST_PAD_SRC,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("{ I420, YV12 }"))
+    );
+
+static GstStaticPadTemplate gst_video_detect_sink_template =
+GST_STATIC_PAD_TEMPLATE ("sink",
+    GST_PAD_SINK,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("{ I420, YV12 }"))
+    );
+
+static GstVideoFilterClass *parent_class = NULL;
+
+static gboolean
+gst_video_detect_set_caps (GstBaseTransform * btrans, GstCaps * incaps,
+    GstCaps * outcaps)
+{
+  GstVideoDetect *vf;
+  GstStructure *in_s;
+  gboolean ret;
+
+  vf = GST_VIDEO_DETECT (btrans);
+
+  in_s = gst_caps_get_structure (incaps, 0);
+
+  ret = gst_structure_get_int (in_s, "width", &vf->width);
+  ret &= gst_structure_get_int (in_s, "height", &vf->height);
+  ret &= gst_structure_get_fourcc (in_s, "format", &vf->format);
+
+  return ret;
+}
+
+/* Useful macros */
+#define GST_VIDEO_I420_Y_ROWSTRIDE(width) (GST_ROUND_UP_4(width))
+#define GST_VIDEO_I420_U_ROWSTRIDE(width) (GST_ROUND_UP_8(width)/2)
+#define GST_VIDEO_I420_V_ROWSTRIDE(width) ((GST_ROUND_UP_8(GST_VIDEO_I420_Y_ROWSTRIDE(width)))/2)
+
+#define GST_VIDEO_I420_Y_OFFSET(w,h) (0)
+#define GST_VIDEO_I420_U_OFFSET(w,h) (GST_VIDEO_I420_Y_OFFSET(w,h)+(GST_VIDEO_I420_Y_ROWSTRIDE(w)*GST_ROUND_UP_2(h)))
+#define GST_VIDEO_I420_V_OFFSET(w,h) (GST_VIDEO_I420_U_OFFSET(w,h)+(GST_VIDEO_I420_U_ROWSTRIDE(w)*GST_ROUND_UP_2(h)/2))
+
+#define GST_VIDEO_I420_SIZE(w,h)     (GST_VIDEO_I420_V_OFFSET(w,h)+(GST_VIDEO_I420_V_ROWSTRIDE(w)*GST_ROUND_UP_2(h)/2))
+
+static void
+gst_video_detect_post_message (GstVideoDetect * videodetect, GstBuffer * buffer,
+    guint data)
+{
+  GstBaseTransform *trans;
+  GstMessage *m;
+  guint64 duration, timestamp, running_time, stream_time;
+
+  trans = GST_BASE_TRANSFORM_CAST (videodetect);
+
+  /* get timestamps */
+  timestamp = GST_BUFFER_TIMESTAMP (buffer);
+  duration = GST_BUFFER_DURATION (buffer);
+  running_time = gst_segment_to_running_time (&trans->segment, GST_FORMAT_TIME,
+      timestamp);
+  stream_time = gst_segment_to_stream_time (&trans->segment, GST_FORMAT_TIME,
+      timestamp);
+
+  /* post message */
+  m = gst_message_new_element (GST_OBJECT_CAST (videodetect),
+      gst_structure_new ("GstVideoDetect",
+          "have-pattern", G_TYPE_BOOLEAN, videodetect->in_pattern,
+          "timestamp", G_TYPE_UINT64, timestamp,
+          "stream-time", G_TYPE_UINT64, stream_time,
+          "running-time", G_TYPE_UINT64, running_time,
+          "duration", G_TYPE_UINT64, duration,
+          "data", G_TYPE_UINT, data, NULL));
+  gst_element_post_message (GST_ELEMENT_CAST (videodetect), m);
+}
+
+static gdouble
+gst_video_detect_calc_brightness (GstVideoDetect * videodetect, guint8 * data,
+    gint width, gint height, gint stride)
+{
+  gint i, j;
+  guint64 sum;
+
+  sum = 0;
+  for (i = 0; i < height; i++) {
+    for (j = 0; j < width; j++) {
+      sum += data[j];
+    }
+    /* move to next line */
+    data += stride;
+  }
+  return sum / (255.0 * width * height);
+}
+
+static void
+gst_video_detect_420 (GstVideoDetect * videodetect, GstBuffer * buffer)
+{
+  gdouble brightness;
+  gint i, pw, ph, stride, width, height;
+  guint8 *d, *data;
+  guint pattern_data;
+
+  data = GST_BUFFER_DATA (buffer);
+
+  width = videodetect->width;
+  height = videodetect->height;
+
+  pw = videodetect->pattern_width;
+  ph = videodetect->pattern_height;
+  stride = GST_VIDEO_I420_Y_ROWSTRIDE (width);
+
+  /* analyse the bottom left pixels */
+  for (i = 0; i < videodetect->pattern_count; i++) {
+    d = data;
+    /* move to start of bottom left */
+    d += stride * (height - ph);
+    /* move to i-th pattern */
+    d += pw * i;
+
+    /* calc brightness of width * height box */
+    brightness =
+        gst_video_detect_calc_brightness (videodetect, d, pw, ph, stride);
+
+    GST_DEBUG_OBJECT (videodetect, "brightness %f", brightness);
+
+    if (i & 1) {
+      /* odd pixels must be white */
+      if (brightness < (1.0 - videodetect->pattern_sensitivity))
+        goto no_pattern;
+    } else {
+      /* even pixels must be black */
+      if (brightness > videodetect->pattern_sensitivity)
+        goto no_pattern;
+    }
+  }
+  GST_DEBUG_OBJECT (videodetect, "found pattern");
+
+  pattern_data = 0;
+
+  /* get the data of the pattern */
+  for (i = 0; i < videodetect->pattern_data_count; i++) {
+    d = data;
+    /* move to start of bottom left, after the pattern */
+    d += stride * (height - ph) + (videodetect->pattern_count * pw);
+    /* move to i-th pattern data */
+    d += pw * i;
+
+    /* calc brightness of width * height box */
+    brightness =
+        gst_video_detect_calc_brightness (videodetect, d, pw, ph, stride);
+    /* update pattern */
+    pattern_data <<= 1;
+    if (brightness > 0.5)
+      pattern_data |= 1;
+  }
+
+  GST_DEBUG_OBJECT (videodetect, "have data %u", pattern_data);
+
+  videodetect->in_pattern = TRUE;
+  gst_video_detect_post_message (videodetect, buffer, pattern_data);
+
+  return;
+
+no_pattern:
+  {
+    GST_DEBUG_OBJECT (videodetect, "no pattern found");
+    if (videodetect->in_pattern) {
+      videodetect->in_pattern = FALSE;
+      gst_video_detect_post_message (videodetect, buffer, 0);
+    }
+    return;
+  }
+}
+
+static GstFlowReturn
+gst_video_detect_transform_ip (GstBaseTransform * trans, GstBuffer * buf)
+{
+  GstVideoDetect *videodetect;
+  GstFlowReturn ret = GST_FLOW_OK;
+
+  videodetect = GST_VIDEO_DETECT (trans);
+
+  gst_video_detect_420 (videodetect, buf);
+
+  return ret;
+}
+
+static void
+gst_video_detect_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec)
+{
+  GstVideoDetect *videodetect;
+
+  videodetect = GST_VIDEO_DETECT (object);
+
+  switch (prop_id) {
+    case PROP_MESSAGE:
+      videodetect->message = g_value_get_boolean (value);
+      break;
+    case PROP_PATTERN_WIDTH:
+      videodetect->pattern_width = g_value_get_int (value);
+      break;
+    case PROP_PATTERN_HEIGHT:
+      videodetect->pattern_height = g_value_get_int (value);
+      break;
+    case PROP_PATTERN_COUNT:
+      videodetect->pattern_count = g_value_get_int (value);
+      break;
+    case PROP_PATTERN_DATA_COUNT:
+      videodetect->pattern_data_count = g_value_get_int (value);
+      break;
+    case PROP_PATTERN_SENSITIVITY:
+      videodetect->pattern_sensitivity = g_value_get_double (value);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+gst_video_detect_get_property (GObject * object, guint prop_id, GValue * value,
+    GParamSpec * pspec)
+{
+  GstVideoDetect *videodetect;
+
+  videodetect = GST_VIDEO_DETECT (object);
+
+  switch (prop_id) {
+    case PROP_MESSAGE:
+      g_value_set_boolean (value, videodetect->message);
+      break;
+    case PROP_PATTERN_WIDTH:
+      g_value_set_int (value, videodetect->pattern_width);
+      break;
+    case PROP_PATTERN_HEIGHT:
+      g_value_set_int (value, videodetect->pattern_height);
+      break;
+    case PROP_PATTERN_COUNT:
+      g_value_set_int (value, videodetect->pattern_count);
+      break;
+    case PROP_PATTERN_DATA_COUNT:
+      g_value_set_int (value, videodetect->pattern_data_count);
+      break;
+    case PROP_PATTERN_SENSITIVITY:
+      g_value_set_double (value, videodetect->pattern_sensitivity);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+gst_video_detect_base_init (gpointer g_class)
+{
+  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
+
+  gst_element_class_set_details (element_class, &video_detect_details);
+
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&gst_video_detect_sink_template));
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&gst_video_detect_src_template));
+}
+
+static void
+gst_video_detect_class_init (gpointer klass, gpointer class_data)
+{
+  GObjectClass *gobject_class;
+  GstBaseTransformClass *trans_class;
+
+  gobject_class = (GObjectClass *) klass;
+  trans_class = (GstBaseTransformClass *) klass;
+
+  parent_class = g_type_class_peek_parent (klass);
+
+  gobject_class->set_property = gst_video_detect_set_property;
+  gobject_class->get_property = gst_video_detect_get_property;
+
+  g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_MESSAGE,
+      g_param_spec_boolean ("message", "Message",
+          "Post statics messages",
+          DEFAULT_MESSAGE, G_PARAM_READWRITE | G_PARAM_CONSTRUCT));
+  g_object_class_install_property (gobject_class, PROP_PATTERN_WIDTH,
+      g_param_spec_int ("pattern-width", "Pattern width",
+          "The width of the pattern markers", 1, G_MAXINT,
+          DEFAULT_PATTERN_WIDTH, G_PARAM_READWRITE | G_PARAM_CONSTRUCT));
+  g_object_class_install_property (gobject_class, PROP_PATTERN_HEIGHT,
+      g_param_spec_int ("pattern-height", "Pattern height",
+          "The height of the pattern markers", 1, G_MAXINT,
+          DEFAULT_PATTERN_HEIGHT, G_PARAM_READWRITE | G_PARAM_CONSTRUCT));
+  g_object_class_install_property (gobject_class, PROP_PATTERN_COUNT,
+      g_param_spec_int ("pattern-count", "Pattern count",
+          "The number of pattern markers", 1, G_MAXINT,
+          DEFAULT_PATTERN_COUNT, G_PARAM_READWRITE | G_PARAM_CONSTRUCT));
+  g_object_class_install_property (gobject_class, PROP_PATTERN_DATA_COUNT,
+      g_param_spec_int ("pattern-data-count", "Pattern data count",
+          "The number of extra data pattern markers", 0, G_MAXINT,
+          DEFAULT_PATTERN_DATA_COUNT, G_PARAM_READWRITE | G_PARAM_CONSTRUCT));
+  g_object_class_install_property (gobject_class, PROP_PATTERN_SENSITIVITY,
+      g_param_spec_double ("pattern-sensitivity", "Pattern sensitivity",
+          "The sensitivity for detecting the markers (0.0 = highest, 0.5 lowest)",
+          0.0, 0.5, DEFAULT_PATTERN_SENSITIVITY,
+          G_PARAM_READWRITE | G_PARAM_CONSTRUCT));
+
+  trans_class->set_caps = GST_DEBUG_FUNCPTR (gst_video_detect_set_caps);
+  trans_class->transform_ip = GST_DEBUG_FUNCPTR (gst_video_detect_transform_ip);
+  trans_class->passthrough_on_same_caps = TRUE;
+
+  GST_DEBUG_CATEGORY_INIT (video_detect_debug, "videodetect", 0,
+      "Video detect");
+}
+
+static void
+gst_video_detect_init (GTypeInstance * instance, gpointer g_class)
+{
+  GstVideoDetect *videodetect;
+
+  videodetect = GST_VIDEO_DETECT (instance);
+
+  GST_DEBUG_OBJECT (videodetect, "gst_video_detect_init");
+
+  videodetect->in_pattern = FALSE;
+}
+
+GType
+gst_video_detect_get_type (void)
+{
+  static GType video_detect_type = 0;
+
+  if (!video_detect_type) {
+    static const GTypeInfo video_detect_info = {
+      sizeof (GstVideoDetectClass),
+      gst_video_detect_base_init,
+      NULL,
+      gst_video_detect_class_init,
+      NULL,
+      NULL,
+      sizeof (GstVideoDetect),
+      0,
+      gst_video_detect_init,
+    };
+
+    video_detect_type = g_type_register_static (GST_TYPE_VIDEO_FILTER,
+        "GstVideoDetect", &video_detect_info, 0);
+  }
+  return video_detect_type;
+}
diff --git a/gst/videosignal/gstvideodetect.h b/gst/videosignal/gstvideodetect.h
new file mode 100644
index 00000000..8fa5c05f
--- /dev/null
+++ b/gst/videosignal/gstvideodetect.h
@@ -0,0 +1,70 @@
+/* GStreamer
+ * Copyright (C) <2006> Wim Taymans <wim@fluendo.com>
+ *
+ * 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.
+ */
+
+#ifndef __GST_VIDEO_DETECT_H__
+#define __GST_VIDEO_DETECT_H__
+
+#include <gst/video/gstvideofilter.h>
+
+G_BEGIN_DECLS
+
+#define GST_TYPE_VIDEO_DETECT \
+  (gst_video_detect_get_type())
+#define GST_VIDEO_DETECT(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_VIDEO_DETECT,GstVideoDetect))
+#define GST_VIDEO_DETECT_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_VIDEO_DETECT,GstVideoDetectClass))
+#define GST_IS_VIDEO_DETECT(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_VIDEO_DETECT))
+#define GST_IS_VIDEO_DETECT_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_VIDEO_DETECT))
+
+typedef struct _GstVideoDetect GstVideoDetect;
+typedef struct _GstVideoDetectClass GstVideoDetectClass;
+
+/**
+ * GstVideoDetect:
+ *
+ * Opaque datastructure.
+ */
+struct _GstVideoDetect {
+  GstVideoFilter videofilter;
+  
+  gint width, height;
+  guint32 format;
+
+  gboolean message;
+  gint pattern_width;
+  gint pattern_height;
+  gint pattern_count;
+  gint pattern_data_count;
+  gdouble pattern_sensitivity;
+
+  gboolean in_pattern;
+};
+
+struct _GstVideoDetectClass {
+  GstVideoFilterClass parent_class;
+};
+
+GType gst_video_detect_get_type (void);
+
+G_END_DECLS
+
+#endif /* __GST_VIDEO_DETECT_H__ */
diff --git a/gst/videosignal/gstvideosignal.c b/gst/videosignal/gstvideosignal.c
new file mode 100644
index 00000000..55b81cc2
--- /dev/null
+++ b/gst/videosignal/gstvideosignal.c
@@ -0,0 +1,45 @@
+/* GStreamer
+ * Copyright (C) <2007> Wim Taymans <wim@fluendo.com>
+ *
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "gstvideoanalyse.h"
+#include "gstvideodetect.h"
+
+static gboolean
+plugin_init (GstPlugin * plugin)
+{
+  gboolean res;
+
+  res = gst_element_register (plugin, "videoanalyse", GST_RANK_NONE,
+      GST_TYPE_VIDEO_ANALYSE);
+
+  res &= gst_element_register (plugin, "videodetect", GST_RANK_NONE,
+      GST_TYPE_VIDEO_DETECT);
+
+  return res;
+}
+
+GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
+    GST_VERSION_MINOR,
+    "videosignal",
+    "Various video signal analysers",
+    plugin_init, VERSION, GST_LICENSE, GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN);
diff --git a/gst/videosignal/gstvideosignal.h b/gst/videosignal/gstvideosignal.h
new file mode 100644
index 00000000..ffbc913c
--- /dev/null
+++ b/gst/videosignal/gstvideosignal.h
@@ -0,0 +1,65 @@
+/* GStreamer
+ * Copyright (C) <2006> Wim Taymans <wim@fluendo.com>
+ *
+ * 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.
+ */
+
+#ifndef __GST_VIDEO_SIGNAL_H__
+#define __GST_VIDEO_SIGNAL_H__
+
+#include <gst/video/gstvideofilter.h>
+
+G_BEGIN_DECLS
+
+#define GST_TYPE_VIDEO_SIGNAL \
+  (gst_video_signal_get_type())
+#define GST_VIDEO_SIGNAL(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_VIDEO_SIGNAL,GstVideoSignal))
+#define GST_VIDEO_SIGNAL_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_VIDEO_SIGNAL,GstVideoSignalClass))
+#define GST_IS_VIDEO_SIGNAL(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_VIDEO_SIGNAL))
+#define GST_IS_VIDEO_SIGNAL_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_VIDEO_SIGNAL))
+
+typedef struct _GstVideoSignal GstVideoSignal;
+typedef struct _GstVideoSignalClass GstVideoSignalClass;
+
+/**
+ * GstVideoSignal:
+ *
+ * Opaque datastructure.
+ */
+struct _GstVideoSignal {
+  GstVideoFilter videofilter;
+  
+  gint width, height;
+
+  gdouble brightness;
+  gdouble brightness_var;
+
+  guint64 interval;
+};
+
+struct _GstVideoSignalClass {
+  GstVideoFilterClass parent_class;
+};
+
+GType gst_video_signal_get_type (void);
+
+G_END_DECLS
+
+#endif /* __GST_VIDEO_SIGNAL_H__ */