--- /dev/null
+/* GStreamer Element
+ *
+ * Copyright 2011 Collabora Ltd.
+ * @author: Mark Nauwelaerts <mark.nauwelaerts@collabora.co.uk>
+ * Copyright 2011 Nokia Corp.
+ *
+ * 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 <string.h>
+
+#include <gst/gst.h>
+#include <gst/base/gstcollectpads.h>
+#include <gst/video/video.h>
+
+#include "gstcompare.h"
+
+GST_DEBUG_CATEGORY_STATIC (compare_debug);
+#define GST_CAT_DEFAULT compare_debug
+
+
+static GstStaticPadTemplate src_factory = GST_STATIC_PAD_TEMPLATE ("src",
+ GST_PAD_SRC,
+ GST_PAD_ALWAYS,
+ GST_STATIC_CAPS_ANY);
+
+static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink",
+ GST_PAD_SINK,
+ GST_PAD_ALWAYS,
+ GST_STATIC_CAPS_ANY);
+
+static GstStaticPadTemplate check_sink_factory =
+GST_STATIC_PAD_TEMPLATE ("check",
+ GST_PAD_SINK,
+ GST_PAD_ALWAYS,
+ GST_STATIC_CAPS_ANY);
+
+enum GstCompareMethod
+{
+ GST_COMPARE_METHOD_MEM,
+ GST_COMPARE_METHOD_MAX,
+ GST_COMPARE_METHOD_SSIM
+};
+
+#define GST_COMPARE_METHOD_TYPE (gst_compare_method_get_type())
+static GType
+gst_compare_method_get_type (void)
+{
+ static GType method_type = 0;
+
+ static const GEnumValue method_types[] = {
+ {GST_COMPARE_METHOD_MEM, "Memory", "mem"},
+ {GST_COMPARE_METHOD_MAX, "Maximum metric", "max"},
+ {GST_COMPARE_METHOD_SSIM, "SSIM (raw video)", "ssim"},
+ {0, NULL, NULL}
+ };
+
+ if (!method_type) {
+ method_type = g_enum_register_static ("GstCompareMethod", method_types);
+ }
+ return method_type;
+}
+
+/* Filter signals and args */
+enum
+{
+ /* FILL ME */
+ LAST_SIGNAL
+};
+
+enum
+{
+ PROP_0,
+ PROP_META,
+ PROP_OFFSET_TS,
+ PROP_METHOD,
+ PROP_THRESHOLD,
+ PROP_UPPER,
+ PROP_LAST
+};
+
+#define DEFAULT_META GST_BUFFER_COPY_ALL
+#define DEFAULT_OFFSET_TS FALSE
+#define DEFAULT_METHOD GST_COMPARE_METHOD_MEM
+#define DEFAULT_THRESHOLD 0
+#define DEFAULT_UPPER TRUE
+
+static void gst_compare_set_property (GObject * object,
+ guint prop_id, const GValue * value, GParamSpec * pspec);
+static void gst_compare_get_property (GObject * object,
+ guint prop_id, GValue * value, GParamSpec * pspec);
+
+static void gst_compare_reset (GstCompare * overlay);
+
+static GstCaps *gst_compare_getcaps (GstPad * pad);
+static GstFlowReturn gst_compare_collect_pads (GstCollectPads * cpads,
+ GstCompare * comp);
+
+static GstStateChangeReturn gst_compare_change_state (GstElement * element,
+ GstStateChange transition);
+
+GST_BOILERPLATE (GstCompare, gst_compare, GstElement, GST_TYPE_ELEMENT);
+
+
+static void
+gst_compare_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_add_pad_template (element_class,
+ gst_static_pad_template_get (&check_sink_factory));
+ gst_element_class_set_details_simple (element_class, "Compare buffers",
+ "Filter/Debug", "Compares incoming buffers",
+ "Mark Nauwelaerts <mark.nauwelaerts@collabora.co.uk>");
+}
+
+static void
+gst_compare_finalize (GObject * object)
+{
+ GstCompare *comp = GST_COMPARE (object);
+
+ gst_object_unref (comp->cpads);
+
+ G_OBJECT_CLASS (parent_class)->finalize (object);
+}
+
+static void
+gst_compare_class_init (GstCompareClass * klass)
+{
+ GObjectClass *gobject_class;
+ GstElementClass *gstelement_class;
+
+ gobject_class = (GObjectClass *) klass;
+ gstelement_class = (GstElementClass *) klass;
+
+ GST_DEBUG_CATEGORY_INIT (compare_debug, "compare", 0, "Compare buffers");
+
+ gstelement_class->change_state = GST_DEBUG_FUNCPTR (gst_compare_change_state);
+
+ gobject_class->set_property = gst_compare_set_property;
+ gobject_class->get_property = gst_compare_get_property;
+ gobject_class->finalize = gst_compare_finalize;
+
+ g_object_class_install_property (gobject_class, PROP_META,
+ g_param_spec_flags ("meta", "Compare Meta",
+ "Indicates which metadata should be compared",
+ gst_buffer_copy_flags_get_type (), DEFAULT_META,
+ G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+ g_object_class_install_property (gobject_class, PROP_OFFSET_TS,
+ g_param_spec_boolean ("offset-ts", "Offsets Timestamps",
+ "Consider OFFSET and OFFSET_END part of timestamp metadata",
+ DEFAULT_OFFSET_TS, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+ g_object_class_install_property (gobject_class, PROP_METHOD,
+ g_param_spec_enum ("method", "Content Compare Method",
+ "Method to compare buffer content",
+ GST_COMPARE_METHOD_TYPE, DEFAULT_METHOD,
+ G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+ g_object_class_install_property (gobject_class, PROP_THRESHOLD,
+ g_param_spec_double ("threshold", "Content Threshold",
+ "Threshold beyond which to consider content different as determined by content-method",
+ 0, G_MAXDOUBLE, DEFAULT_THRESHOLD,
+ G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+ g_object_class_install_property (gobject_class, PROP_UPPER,
+ g_param_spec_boolean ("upper", "Threshold Upper Bound",
+ "Whether threshold value is upper bound or lower bound for difference measure",
+ DEFAULT_UPPER, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+}
+
+static void
+gst_compare_init (GstCompare * comp, GstCompareClass * klass)
+{
+ comp->cpads = gst_collect_pads_new ();
+ gst_collect_pads_set_function (comp->cpads,
+ (GstCollectPadsFunction) GST_DEBUG_FUNCPTR (gst_compare_collect_pads),
+ comp);
+
+ comp->sinkpad = gst_pad_new_from_static_template (&sink_factory, "sink");
+ gst_pad_set_getcaps_function (comp->sinkpad, gst_compare_getcaps);
+ gst_element_add_pad (GST_ELEMENT (comp), comp->sinkpad);
+
+ comp->checkpad =
+ gst_pad_new_from_static_template (&check_sink_factory, "check");
+ gst_pad_set_getcaps_function (comp->checkpad, gst_compare_getcaps);
+ gst_element_add_pad (GST_ELEMENT (comp), comp->checkpad);
+
+ gst_collect_pads_add_pad_full (comp->cpads, comp->sinkpad,
+ sizeof (GstCollectData), NULL);
+ gst_collect_pads_add_pad_full (comp->cpads, comp->checkpad,
+ sizeof (GstCollectData), NULL);
+
+ comp->srcpad = gst_pad_new_from_static_template (&src_factory, "src");
+ gst_pad_set_getcaps_function (comp->srcpad, gst_compare_getcaps);
+ gst_element_add_pad (GST_ELEMENT (comp), comp->srcpad);
+
+ /* init properties */
+ comp->meta = DEFAULT_META;
+ comp->offset_ts = DEFAULT_OFFSET_TS;
+ comp->method = DEFAULT_METHOD;
+ comp->threshold = DEFAULT_THRESHOLD;
+ comp->upper = DEFAULT_UPPER;
+
+ gst_compare_reset (comp);
+}
+
+static void
+gst_compare_reset (GstCompare * comp)
+{
+}
+
+static GstCaps *
+gst_compare_getcaps (GstPad * pad)
+{
+ GstCompare *comp;
+ GstPad *otherpad;
+ GstCaps *result;
+
+ comp = GST_COMPARE (gst_pad_get_parent (pad));
+ if (G_UNLIKELY (comp == NULL))
+ return gst_caps_new_any ();
+
+ otherpad = (pad == comp->srcpad ? comp->sinkpad : comp->srcpad);
+ result = gst_pad_peer_get_caps (otherpad);
+ if (result == NULL)
+ result = gst_caps_new_any ();
+
+ gst_object_unref (comp);
+
+ return result;
+}
+
+static void
+gst_compare_meta (GstCompare * comp, GstBuffer * buf1, GstBuffer * buf2)
+{
+ gint flags = 0;
+
+ if (comp->meta & GST_BUFFER_COPY_FLAGS) {
+ if (GST_BUFFER_FLAGS (buf1) != GST_BUFFER_FLAGS (buf2)) {
+ flags |= GST_BUFFER_COPY_FLAGS;
+ GST_DEBUG_OBJECT (comp, "flags %d != flags %d", GST_BUFFER_FLAGS (buf1),
+ GST_BUFFER_FLAGS (buf2));
+ }
+ }
+ if (comp->meta & GST_BUFFER_COPY_TIMESTAMPS) {
+ if (GST_BUFFER_TIMESTAMP (buf1) != GST_BUFFER_TIMESTAMP (buf2)) {
+ flags |= GST_BUFFER_COPY_TIMESTAMPS;
+ GST_DEBUG_OBJECT (comp,
+ "ts %" GST_TIME_FORMAT " != ts %" GST_TIME_FORMAT,
+ GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (buf1)),
+ GST_TIME_ARGS (GST_BUFFER_TIMESTAMP (buf2)));
+ }
+ if (GST_BUFFER_DURATION (buf1) != GST_BUFFER_DURATION (buf2)) {
+ flags |= GST_BUFFER_COPY_TIMESTAMPS;
+ GST_DEBUG_OBJECT (comp,
+ "dur %" GST_TIME_FORMAT " != dur %" GST_TIME_FORMAT,
+ GST_TIME_ARGS (GST_BUFFER_DURATION (buf1)),
+ GST_TIME_ARGS (GST_BUFFER_DURATION (buf2)));
+ }
+ if (comp->offset_ts) {
+ if (GST_BUFFER_OFFSET (buf1) != GST_BUFFER_OFFSET (buf2)) {
+ flags |= GST_BUFFER_COPY_TIMESTAMPS;
+ GST_DEBUG_OBJECT (comp,
+ "offset %" G_GINT64_FORMAT " != offset %" G_GINT64_FORMAT,
+ GST_BUFFER_OFFSET (buf1), GST_BUFFER_OFFSET (buf2));
+ }
+ if (GST_BUFFER_OFFSET_END (buf1) != GST_BUFFER_OFFSET_END (buf2)) {
+ flags |= GST_BUFFER_COPY_TIMESTAMPS;
+ GST_DEBUG_OBJECT (comp,
+ "offset_end %" G_GINT64_FORMAT " != offset_end %" G_GINT64_FORMAT,
+ GST_BUFFER_OFFSET_END (buf1), GST_BUFFER_OFFSET_END (buf2));
+ }
+ }
+ }
+ if (comp->meta & GST_BUFFER_COPY_CAPS) {
+ if (!gst_caps_is_equal (GST_BUFFER_CAPS (buf1), GST_BUFFER_CAPS (buf2))) {
+ flags |= GST_BUFFER_COPY_CAPS;
+ GST_DEBUG_OBJECT (comp,
+ "caps %" GST_PTR_FORMAT " != caps %" GST_PTR_FORMAT,
+ GST_BUFFER_CAPS (buf1), GST_BUFFER_CAPS (buf2));
+ }
+ }
+
+ /* signal mismatch by debug and message */
+ if (flags) {
+ GST_WARNING_OBJECT (comp, "buffers %p and %p failed metadata match %d",
+ buf1, buf2, flags);
+
+ gst_element_post_message (GST_ELEMENT (comp),
+ gst_message_new_element (GST_OBJECT (comp),
+ gst_structure_new ("delta", "meta", G_TYPE_INT, flags, NULL)));
+ }
+}
+
+/* when comparing contents, it is already ensured sizes are equal */
+
+static gint
+gst_compare_mem (GstCompare * comp, GstBuffer * buf1, GstBuffer * buf2)
+{
+ return memcmp (GST_BUFFER_DATA (buf1), GST_BUFFER_DATA (buf2),
+ GST_BUFFER_SIZE (buf1)) ? 1 : 0;
+}
+
+static gint
+gst_compare_max (GstCompare * comp, GstBuffer * buf1, GstBuffer * buf2)
+{
+ gint i, delta = 0;
+ gint8 *data1, *data2;
+
+ data1 = (gint8 *) GST_BUFFER_DATA (buf1);
+ data2 = (gint8 *) GST_BUFFER_DATA (buf2);
+
+ /* primitive loop */
+ for (i = 0; i < GST_BUFFER_SIZE (buf1); i++) {
+ gint diff = ABS (*data1 - *data2);
+ if (diff > 0)
+ GST_LOG_OBJECT (comp, "diff at %d = %d", i, diff);
+ delta = MAX (delta, ABS (*data1 - *data2));
+ data1++;
+ data2++;
+ }
+
+ return delta;
+}
+
+static double
+gst_compare_ssim_window (GstCompare * comp, guint8 * data1, guint8 * data2,
+ gint width, gint height, gint step, gint stride)
+{
+ gint count = 0, i, j;
+ gint sum1 = 0, sum2 = 0, ssum1 = 0, ssum2 = 0, acov = 0;
+ gdouble avg1, avg2, var1, var2, cov;
+
+ const gdouble k1 = 0.01;
+ const gdouble k2 = 0.03;
+ const gdouble L = 255.0;
+ const gdouble c1 = (k1 * L) * (k1 * L);
+ const gdouble c2 = (k2 * L) * (k2 * L);
+
+ /* plain and simple; no fancy optimizations */
+ for (i = 0; i < height; i++) {
+ for (j = 0; j < width; j++) {
+ sum1 += *data1;
+ sum2 += *data2;
+ ssum1 += *data1 * *data1;
+ ssum2 += *data2 * *data2;
+ acov += *data1 * *data2;
+ count++;
+ data1 += step;
+ data2 += step;
+ }
+ data1 -= j * step;
+ data2 -= j * step;
+ data1 += stride;
+ data2 += stride;
+ }
+
+ avg1 = sum1 / count;
+ avg2 = sum2 / count;
+ var1 = ssum1 / count - avg1 * avg1;
+ var2 = ssum2 / count - avg2 * avg2;
+ cov = acov / count - avg1 * avg2;
+
+ return (2 * avg1 * avg2 + c1) * (2 * cov + c2) /
+ ((avg1 * avg1 + avg2 * avg2 + c1) * (var1 + var2 + c2));
+}
+
+/* @width etc are for the particular component */
+static gdouble
+gst_compare_ssim_component (GstCompare * comp, guint8 * data1, guint8 * data2,
+ gint width, gint height, gint step, gint stride)
+{
+ const gint window = 16;
+ gdouble ssim_sum = 0;
+ gint count = 0, i, j;
+
+ for (j = 0; j + (window / 2) < height; j += (window / 2)) {
+ for (i = 0; i + (window / 2) < width; i += (window / 2)) {
+ gdouble ssim;
+
+ ssim = gst_compare_ssim_window (comp, data1 + step * i + j * stride,
+ data2 + step * i + j * stride,
+ MIN (window, width - i), MIN (window, height - j), step, stride);
+ GST_LOG_OBJECT (comp, "ssim for %dx%d at (%d, %d) = %f", window, window,
+ i, j, ssim);
+ ssim_sum += ssim;
+ count++;
+ }
+ }
+
+ return (ssim_sum / count);
+}
+
+static gdouble
+gst_compare_ssim (GstCompare * comp, GstBuffer * buf1, GstBuffer * buf2)
+{
+ GstCaps *caps;
+ GstVideoFormat format, f;
+ gint width, height, w, h, i, comps;
+ gdouble cssim[4], ssim, c[4] = { 1.0, 0.0, 0.0, 0.0 };
+ guint8 *data1, *data2;
+
+ caps = GST_BUFFER_CAPS (buf1);
+ if (!caps)
+ goto invalid_input;
+
+ if (!gst_video_format_parse_caps (caps, &format, &width, &height))
+ goto invalid_input;
+
+ caps = GST_BUFFER_CAPS (buf2);
+ if (!caps)
+ goto invalid_input;
+
+ if (!gst_video_format_parse_caps (caps, &f, &w, &h))
+ goto invalid_input;
+
+ if (f != format || w != width || h != height)
+ return comp->threshold + 1;
+
+ comps = gst_video_format_is_gray (format) ? 1 : 3;
+ if (gst_video_format_has_alpha (format))
+ comps += 1;
+
+ /* note that some are reported both yuv and gray */
+ for (i = 0; i < comps; ++i)
+ c[i] = 1.0;
+ /* increase luma weight if yuv */
+ if (gst_video_format_is_yuv (format) && (comps > 1))
+ c[0] = comps - 1;
+ for (i = 0; i < comps; ++i)
+ c[i] /= (gst_video_format_is_yuv (format) && (comps > 1)) ?
+ 2 * (comps - 1) : comps;
+
+ data1 = GST_BUFFER_DATA (buf1);
+ data2 = GST_BUFFER_DATA (buf2);
+ for (i = 0; i < comps; i++) {
+ gint offset, cw, ch, step, stride;
+
+ /* only support most common formats */
+ if (gst_video_format_get_component_depth (format, i) != 8)
+ goto unsupported_input;
+ offset = gst_video_format_get_component_offset (format, i, width, height);
+ cw = gst_video_format_get_component_width (format, i, width);
+ ch = gst_video_format_get_component_height (format, i, height);
+ step = gst_video_format_get_pixel_stride (format, i);
+ stride = gst_video_format_get_row_stride (format, i, width);
+
+ GST_LOG_OBJECT (comp, "component %d", i);
+ cssim[i] = gst_compare_ssim_component (comp, data1 + offset, data2 + offset,
+ cw, ch, step, stride);
+ GST_LOG_OBJECT (comp, "ssim[%d] = %f", i, cssim[i]);
+ }
+
+#ifndef GST_DISABLE_GST_DEBUG
+ for (i = 0; i < 4; i++) {
+ GST_DEBUG_OBJECT (comp, "ssim[%d] = %f, c[%d] = %f", i, cssim[i], i, c[i]);
+ }
+#endif
+
+ ssim = cssim[0] * c[0] + cssim[1] * c[1] + cssim[2] * c[2] + cssim[3] * c[3];
+
+ return ssim;
+
+ /* ERRORS */
+invalid_input:
+ {
+ GST_ERROR_OBJECT (comp, "ssim method needs raw video input");
+ return 0;
+ }
+unsupported_input:
+ {
+ GST_ERROR_OBJECT (comp, "raw video format not supported %" GST_PTR_FORMAT,
+ caps);
+ return 0;
+ }
+}
+
+static void
+gst_compare_buffers (GstCompare * comp, GstBuffer * buf1, GstBuffer * buf2)
+{
+ gdouble delta = 0;
+
+ /* first check metadata */
+ gst_compare_meta (comp, buf1, buf2);
+
+ /* check content according to method */
+ /* but at least size should match */
+ if (GST_BUFFER_SIZE (buf1) != GST_BUFFER_SIZE (buf2)) {
+ delta = comp->threshold + 1;
+ } else {
+ GST_MEMDUMP_OBJECT (comp, "buffer 1", GST_BUFFER_DATA (buf1),
+ GST_BUFFER_SIZE (buf1));
+ GST_MEMDUMP_OBJECT (comp, "buffer 2", GST_BUFFER_DATA (buf2),
+ GST_BUFFER_SIZE (buf2));
+ switch (comp->method) {
+ case GST_COMPARE_METHOD_MEM:
+ delta = gst_compare_mem (comp, buf1, buf2);
+ break;
+ case GST_COMPARE_METHOD_MAX:
+ delta = gst_compare_max (comp, buf1, buf2);
+ break;
+ case GST_COMPARE_METHOD_SSIM:
+ delta = gst_compare_ssim (comp, buf1, buf2);
+ break;
+ default:
+ g_assert_not_reached ();
+ break;
+ }
+ }
+
+ if ((comp->upper && delta > comp->threshold) ||
+ (!comp->upper && delta < comp->threshold)) {
+ GST_WARNING_OBJECT (comp, "buffers %p and %p failed content match %f",
+ buf1, buf2, delta);
+
+ gst_element_post_message (GST_ELEMENT (comp),
+ gst_message_new_element (GST_OBJECT (comp),
+ gst_structure_new ("delta", "content", G_TYPE_DOUBLE, delta,
+ NULL)));
+ }
+}
+
+static GstFlowReturn
+gst_compare_collect_pads (GstCollectPads * cpads, GstCompare * comp)
+{
+ GstBuffer *buf1, *buf2;
+
+ buf1 = gst_collect_pads_pop (comp->cpads,
+ gst_pad_get_element_private (comp->sinkpad));
+
+ buf2 = gst_collect_pads_pop (comp->cpads,
+ gst_pad_get_element_private (comp->checkpad));
+
+ if (!buf1 && !buf2) {
+ gst_pad_push_event (comp->srcpad, gst_event_new_eos ());
+ return GST_FLOW_UNEXPECTED;
+ } else if (buf1 && buf2) {
+ gst_compare_buffers (comp, buf1, buf2);
+ } else {
+ GST_WARNING_OBJECT (comp, "buffer %p != NULL", buf1 ? buf1 : buf2);
+
+ comp->count++;
+ gst_element_post_message (GST_ELEMENT (comp),
+ gst_message_new_element (GST_OBJECT (comp),
+ gst_structure_new ("delta", "count", G_TYPE_INT, comp->count,
+ NULL)));
+ }
+
+ if (buf1)
+ gst_pad_push (comp->srcpad, buf1);
+
+ if (buf2)
+ gst_buffer_unref (buf2);
+
+ return GST_FLOW_OK;
+}
+
+static void
+gst_compare_set_property (GObject * object, guint prop_id,
+ const GValue * value, GParamSpec * pspec)
+{
+ GstCompare *comp = GST_COMPARE (object);
+
+ switch (prop_id) {
+ case PROP_META:
+ comp->meta = g_value_get_flags (value);
+ break;
+ case PROP_OFFSET_TS:
+ comp->offset_ts = g_value_get_boolean (value);
+ break;
+ case PROP_METHOD:
+ comp->method = g_value_get_enum (value);
+ break;
+ case PROP_THRESHOLD:
+ comp->threshold = g_value_get_double (value);
+ break;
+ case PROP_UPPER:
+ comp->upper = g_value_get_boolean (value);
+ break;
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+ break;
+ }
+}
+
+static void
+gst_compare_get_property (GObject * object, guint prop_id, GValue * value,
+ GParamSpec * pspec)
+{
+ GstCompare *comp = GST_COMPARE (object);
+
+ switch (prop_id) {
+ case PROP_META:
+ g_value_set_flags (value, comp->meta);
+ break;
+ case PROP_OFFSET_TS:
+ g_value_set_boolean (value, comp->offset_ts);
+ break;
+ case PROP_METHOD:
+ g_value_set_enum (value, comp->method);
+ break;
+ case PROP_THRESHOLD:
+ g_value_set_double (value, comp->threshold);
+ break;
+ case PROP_UPPER:
+ g_value_set_boolean (value, comp->upper);
+ break;
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+ break;
+ }
+}
+
+static GstStateChangeReturn
+gst_compare_change_state (GstElement * element, GstStateChange transition)
+{
+ GstCompare *comp = GST_COMPARE (element);
+ GstStateChangeReturn ret;
+
+ switch (transition) {
+ case GST_STATE_CHANGE_NULL_TO_READY:
+ case GST_STATE_CHANGE_READY_TO_PAUSED:
+ gst_collect_pads_start (comp->cpads);
+ break;
+ case GST_STATE_CHANGE_PAUSED_TO_READY:
+ gst_collect_pads_stop (comp->cpads);
+ break;
+ default:
+ break;
+ }
+
+ ret = GST_CALL_PARENT_WITH_DEFAULT (GST_ELEMENT_CLASS, change_state,
+ (element, transition), GST_STATE_CHANGE_SUCCESS);
+ if (ret != GST_STATE_CHANGE_SUCCESS)
+ return ret;
+
+ switch (transition) {
+ case GST_STATE_CHANGE_PAUSED_TO_READY:
+ gst_compare_reset (comp);
+ break;
+ default:
+ break;
+ }
+
+ return GST_STATE_CHANGE_SUCCESS;
+}