cairooverlay: Add generic Cairo overlay video element.

Allows applications to connect to the "draw" signal of
the element and do their custom drawing there.
Includes an example application demonstrating usage.

Fixes: https://bugzilla.gnome.org/show_bug.cgi?id=595520
This commit is contained in:
Jon Nordby 2011-01-28 02:14:04 +02:00 committed by Sebastian Dröge
parent 3ec3bed497
commit 32dff9df75
14 changed files with 594 additions and 9 deletions

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@ -715,6 +715,13 @@ AG_GST_CHECK_FEATURE(CAIRO, [Cairo graphics rendering], cairo, [
AG_GST_PKG_CHECK_MODULES(CAIRO, cairo >= 1.0.0)
])
dnl *** cairo-gobject ***
translit(dnm, m, l) AM_CONDITIONAL(USE_CAIRO_GOBJECT, true)
AG_GST_CHECK_FEATURE(CAIRO_GOBJECT,
[Cairo graphics rendering gobject bindings], cairooverlay, [
AG_GST_PKG_CHECK_MODULES(CAIRO_GOBJECT, cairo-gobject >= 1.10.0)
])
dnl **** ESound ****
translit(dnm, m, l) AM_CONDITIONAL(USE_ESD, true)
AG_GST_CHECK_FEATURE(ESD, [ESounD sound daemon], esdsink, [
@ -1021,6 +1028,7 @@ AM_CONDITIONAL(USE_AALIB, false)
AM_CONDITIONAL(USE_ANNODEX, false)
AM_CONDITIONAL(USE_BZ2, false)
AM_CONDITIONAL(USE_CAIRO, false)
AM_CONDITIONAL(USE_CAIRO_GOBJECT, false)
AM_CONDITIONAL(USE_DIRECTSOUND, false)
AM_CONDITIONAL(USE_DV1394, false)
AM_CONDITIONAL(USE_ESD, false)
@ -1191,6 +1199,7 @@ tests/Makefile
tests/check/Makefile
tests/examples/Makefile
tests/examples/audiofx/Makefile
tests/examples/cairo/Makefile
tests/examples/equalizer/Makefile
tests/examples/jack/Makefile
tests/examples/level/Makefile

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@ -81,6 +81,7 @@ EXTRA_HFILES = \
$(top_srcdir)/ext/cairo/gsttextoverlay.h \
$(top_srcdir)/ext/cairo/gsttimeoverlay.h \
$(top_srcdir)/ext/cairo/gstcairorender.h \
$(top_srcdir)/ext/cairo/gstcairooverlay.h \
$(top_srcdir)/ext/dv/gstdvdec.h \
$(top_srcdir)/ext/dv/gstdvdemux.h \
$(top_srcdir)/ext/esd/esdsink.h \

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@ -51,6 +51,7 @@
<xi:include href="xml/element-cairotextoverlay.xml" />
<xi:include href="xml/element-cairotimeoverlay.xml" />
<xi:include href="xml/element-cairorender.xml" />
<xi:include href="xml/element-cairooverlay.xml" />
<xi:include href="xml/element-capssetter.xml" />
<xi:include href="xml/element-cmmldec.xml" />
<xi:include href="xml/element-cmmlenc.xml" />

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@ -465,6 +465,18 @@ GST_CAIRO_RENDER_CLASS
gst_cairo_render_get_type
</SECTION>
<SECTION>
<FILE>element-cairooverlay</FILE>
<TITLE>cairooverlay</TITLE>
GstCairoOverlay
<SUBSECTION Standard>
GstCairoOverlayClass
GST_TYPE_CAIRO_OVERLAY
GST_CAIRO_OVERLAY
GST_CAIRO_OVERLAY_CLASS
gst_cairo_overlay_get_type
</SECTION>
<SECTION>
<FILE>element-capssetter</FILE>
<TITLE>capssetter</TITLE>

2
ext/cairo/.gitignore vendored Normal file
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@ -0,0 +1,2 @@
gstcairo-marshal.c
gstcairo-marshal.h

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@ -1,20 +1,45 @@
plugin_LTLIBRARIES = libgstcairo.la
noinst_HEADERS = gsttimeoverlay.h gsttextoverlay.h gstcairorender.h
if USE_CAIRO_GOBJECT
glib_enum_define = GST_CAIRO
glib_gen_prefix = gst_cairo
glib_gen_basename = gstcairo
include $(top_srcdir)/common/gst-glib-gen.mak
built_sources = gstcairo-marshal.c
built_headers = gstcairo-marshal.h
BUILT_SOURCES = $(built_sources) $(built_headers)
gstcairo_gobject_dep_sources = gstcairooverlay.c
gstcairo_gobject_dep_headers = gstcairooverlay.h
CLEANFILES = $(BUILT_SOURCES)
endif
noinst_HEADERS = \
gsttimeoverlay.h \
gsttextoverlay.h \
gstcairorender.h \
$(gstcairo_gobject_dep_headers)
libgstcairo_la_SOURCES = \
gstcairo.c \
gsttimeoverlay.c \
gsttextoverlay.c \
gstcairorender.c
gstcairorender.c \
$(gstcairo_gobject_dep_sources)
nodist_libgstcairo_la_SOURCES = \
$(built_sources)
libgstcairo_la_CFLAGS = \
$(GST_PLUGINS_BASE_CFLAGS) \
$(GST_PLUGINS_BASE_CFLAGS) \
$(GST_BASE_CFLAGS) \
$(GST_CFLAGS) $(CAIRO_CFLAGS)
$(GST_CFLAGS) $(CAIRO_CFLAGS) $(CAIRO_GOBJECT_CFLAGS)
libgstcairo_la_LIBADD = \
$(GST_BASE_LIBS) \
$(GST_LIBS) $(CAIRO_LIBS) $(LIBM)
$(GST_BASE_LIBS) -lgstvideo-$(GST_MAJORMINOR) \
$(GST_LIBS) $(CAIRO_LIBS) $(CAIRO_GOBJECT_LIBS) $(LIBM)
libgstcairo_la_LDFLAGS = $(GST_PLUGIN_LDFLAGS)
libgstcairo_la_LIBTOOLFLAGS = --tag=disable-static
EXTRA_DIST = cairo-marshal.list

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@ -0,0 +1,2 @@
VOID:BOXED,UINT64,UINT64
VOID:BOXED

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@ -25,6 +25,11 @@
#include <gsttimeoverlay.h>
#include <gsttextoverlay.h>
#include <gstcairorender.h>
#ifdef HAVE_CAIRO_GOBJECT
#include <gstcairooverlay.h>
#endif
#include <string.h>
#include <math.h>
@ -37,6 +42,10 @@ plugin_init (GstPlugin * plugin)
GST_TYPE_CAIRO_TEXT_OVERLAY);
gst_element_register (plugin, "cairotimeoverlay", GST_RANK_NONE,
GST_TYPE_CAIRO_TIME_OVERLAY);
#ifdef HAVE_CAIRO_GOBJECT
gst_element_register (plugin, "cairooverlay", GST_RANK_NONE,
GST_TYPE_CAIRO_OVERLAY);
#endif
gst_element_register (plugin, "cairorender", GST_RANK_SECONDARY,
GST_TYPE_CAIRO_RENDER);

245
ext/cairo/gstcairooverlay.c Normal file
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@ -0,0 +1,245 @@
/* GStreamer
* Copyright (C) <2011> Jon Nordby <jononor@gmail.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-cairooverlay
*
* cairooverlay renders an overlay using a application provided render function.
*
* The full example can be found in tests/examples/cairo/cairo_overlay.c
* <refsect2>
* <title>Example code</title>
* |[
*
* #include &lt;gst/gst.h&gt;
* #include &lt;gst/video/video.h&gt;
*
* ...
*
* typedef struct {
* gboolean valid;
* int width;
* int height;
* } CairoOverlayState;
*
* ...
*
* static void
* prepare_overlay (GstElement * overlay, GstCaps * caps, gpointer user_data)
* {
* CairoOverlayState *state = (CairoOverlayState *)user_data;
*
* gst_video_format_parse_caps (caps, NULL, &amp;state-&gt;width, &amp;state-&gt;height);
* state-&gt;valid = TRUE;
* }
*
* static void
* draw_overlay (GstElement * overlay, cairo_t * cr, guint64 timestamp,
* guint64 duration, gpointer user_data)
* {
* CairoOverlayState *s = (CairoOverlayState *)user_data;
* double scale;
*
* if (!s-&gt;valid)
* return;
*
* scale = 2*(((timestamp/(int)1e7) % 70)+30)/100.0;
* cairo_translate(cr, s-&gt;width/2, (s-&gt;height/2)-30);
* cairo_scale (cr, scale, scale);
*
* cairo_move_to (cr, 0, 0);
* cairo_curve_to (cr, 0,-30, -50,-30, -50,0);
* cairo_curve_to (cr, -50,30, 0,35, 0,60 );
* cairo_curve_to (cr, 0,35, 50,30, 50,0 ); *
* cairo_curve_to (cr, 50,-30, 0,-30, 0,0 );
* cairo_set_source_rgba (cr, 0.9, 0.0, 0.1, 0.7);
* cairo_fill (cr);
* }
*
* ...
*
* cairo_overlay = gst_element_factory_make (&quot;cairooverlay&quot;, &quot;overlay&quot;);
*
* g_signal_connect (cairo_overlay, &quot;draw&quot;, G_CALLBACK (draw_overlay),
* overlay_state);
* g_signal_connect (cairo_overlay, &quot;caps-changed&quot;,
* G_CALLBACK (prepare_overlay), overlay_state);
* ...
*
* ]|
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "gstcairooverlay.h"
#include "gstcairo-marshal.h"
#include <gst/video/video.h>
#include <cairo.h>
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
#define ARGB_CAPS GST_VIDEO_CAPS_BGRx " ; " GST_VIDEO_CAPS_BGRA " ; "
#else
#define ARGB_CAPS GST_VIDEO_CAPS_xRGB " ; " GST_VIDEO_CAPS_ARGB " ; "
#endif
static GstStaticPadTemplate gst_cairo_overlay_src_template =
GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS (ARGB_CAPS)
);
static GstStaticPadTemplate gst_cairo_overlay_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS (ARGB_CAPS)
);
GST_BOILERPLATE (GstCairoOverlay, gst_cairo_overlay, GstVideoFilter,
GST_TYPE_VIDEO_FILTER);
enum
{
SIGNAL_DRAW,
SIGNAL_CAPS_CHANGED,
N_SIGNALS
};
static guint gst_cairo_overlay_signals[N_SIGNALS];
static gboolean
gst_cairo_overlay_set_caps (GstBaseTransform * btrans, GstCaps * incaps,
GstCaps * outcaps)
{
GstCairoOverlay *overlay = GST_CAIRO_OVERLAY (btrans);
GstStructure *s = gst_caps_get_structure (incaps, 0);
if (!gst_structure_get_int (s, "bpp", &(overlay->bpp))) {
return FALSE;
}
g_signal_emit (overlay, gst_cairo_overlay_signals[SIGNAL_CAPS_CHANGED], 0,
incaps, NULL);
return G_LIKELY (gst_video_format_parse_caps (incaps,
&overlay->caps_format, &overlay->caps_width, &overlay->caps_height));
}
static GstFlowReturn
gst_cairo_overlay_transform_ip (GstBaseTransform * btrans, GstBuffer * buf)
{
GstCairoOverlay *overlay = GST_CAIRO_OVERLAY (btrans);
cairo_surface_t *surface;
cairo_t *cr;
cairo_format_t format;
format = (overlay->bpp == 32) ? CAIRO_FORMAT_ARGB32 : CAIRO_FORMAT_RGB24;
surface =
cairo_image_surface_create_for_data (GST_BUFFER_DATA (buf), format,
overlay->caps_width, overlay->caps_height, overlay->caps_width * 4);
if (G_UNLIKELY (!surface))
return GST_FLOW_ERROR;
cr = cairo_create (surface);
if (G_UNLIKELY (!cr)) {
cairo_surface_destroy (surface);
return GST_FLOW_ERROR;
}
g_signal_emit (overlay, gst_cairo_overlay_signals[SIGNAL_DRAW], 0,
cr, GST_BUFFER_TIMESTAMP (buf), GST_BUFFER_DURATION (buf), NULL);
cairo_destroy (cr);
cairo_surface_destroy (surface);
return GST_FLOW_OK;
}
static void
gst_cairo_overlay_base_init (gpointer g_class)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
gst_element_class_set_details_simple (element_class, "Cairo overlay",
"Filter/Editor/Video",
"Render overlay on a video stream using Cairo",
"Jon Nordby <jononor@gmail.com>");
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&gst_cairo_overlay_sink_template));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&gst_cairo_overlay_src_template));
}
static void
gst_cairo_overlay_class_init (GstCairoOverlayClass * klass)
{
GstBaseTransformClass *trans_class;
trans_class = (GstBaseTransformClass *) klass;
trans_class->set_caps = gst_cairo_overlay_set_caps;
trans_class->transform_ip = gst_cairo_overlay_transform_ip;
/**
* GstCairoOverlay::draw:
* @overlay: Overlay element emitting the signal.
* @cr: Cairo context to draw to.
* @timestamp: Timestamp (see GstClockTime) of the current buffer.
* @duration: Duration (see GstClockTime) of the current buffer.
*
* This signal is emitted when the overlay should be drawn.
*/
gst_cairo_overlay_signals[SIGNAL_DRAW] =
g_signal_new ("draw",
G_TYPE_FROM_CLASS (klass),
0,
0,
NULL,
NULL,
gst_cairo_marshal_VOID__BOXED_UINT64_UINT64,
G_TYPE_NONE, 3, CAIRO_GOBJECT_TYPE_CONTEXT, G_TYPE_UINT64, G_TYPE_UINT64);
/**
* GstCairoOverlay::caps-changed:
* @overlay: Overlay element emitting the signal.
* @caps: The caps of the element.
*
* This signal is emitted when the caps of the element has changed.
*/
gst_cairo_overlay_signals[SIGNAL_CAPS_CHANGED] =
g_signal_new ("caps-changed",
G_TYPE_FROM_CLASS (klass),
0,
0,
NULL, NULL, gst_cairo_marshal_VOID__BOXED, G_TYPE_NONE, 1, GST_TYPE_CAPS);
}
static void
gst_cairo_overlay_init (GstCairoOverlay * overlay, GstCairoOverlayClass * klass)
{
}

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@ -0,0 +1,60 @@
/* GStreamer
* Copyright (C) <2011> Jon Nordby <jononor@gmail.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_CAIRO_OVERLAY_H__
#define __GST_CAIRO_OVERLAY_H__
#include <gst/gst.h>
#include <gst/video/video.h>
#include <gst/video/gstvideofilter.h>
#include <cairo.h>
#include <cairo-gobject.h>
G_BEGIN_DECLS
#define GST_TYPE_CAIRO_OVERLAY \
(gst_cairo_overlay_get_type())
#define GST_CAIRO_OVERLAY(obj) \
(G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_CAIRO_OVERLAY,GstCairoOverlay))
#define GST_CAIRO_OVERLAY_CLASS(klass) \
(G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_CAIRO_OVERLAY,GstCairoOverlayClass))
#define GST_IS_CAIRO_OVERLAY(obj) \
(G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_CAIRO_OVERLAY))
#define GST_IS_CAIRO_OVERLAY_CLASS(klass) \
(G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_CAIRO_OVERLAY))
typedef struct _GstCairoOverlay {
GstVideoFilter parent_instance;
/* < private > */
GstVideoFormat caps_format;
int caps_width;
int caps_height;
int bpp;
} GstCairoOverlay;
typedef struct _GstCairoOverlayClass {
GstVideoFilterClass parent_class;
} GstCairoOverlayClass;
GType gst_cairo_overlay_get_type(void);
G_END_DECLS
#endif /* __GST_CAIRO_OVERLAY_H__ */

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@ -4,8 +4,16 @@ else
JACK_DIR=
endif
SUBDIRS = audiofx equalizer $(JACK_DIR) level pulse rtp shapewipe spectrum v4l2
if USE_CAIRO
CAIRO_DIR=cairo
else
CAIRO_DIR=
endif
DIST_SUBDIRS = audiofx equalizer jack level pulse rtp shapewipe spectrum v4l2
SUBDIRS = audiofx equalizer $(JACK_DIR) level pulse \
rtp shapewipe spectrum v4l2 $(CAIRO_DIR)
DIST_SUBDIRS = audiofx equalizer jack level pulse \
rtp shapewipe spectrum v4l2 $(CAIRO_DIR)
include $(top_srcdir)/common/parallel-subdirs.mak

1
tests/examples/cairo/.gitignore vendored Normal file
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@ -0,0 +1 @@
cairo_overlay

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@ -0,0 +1,11 @@
if USE_CAIRO_GOBJECT
if HAVE_GTK
noinst_PROGRAMS = cairo_overlay
endif
endif
cairo_overlay_SOURCES = cairo_overlay.c
cairo_overlay_CFLAGS = $(GST_CFLAGS) $(GTK_CFLAGS) $(CAIRO_CFLAGS)
cairo_overlay_LDFLAGS = \
$(GST_LIBS) -lgstinterfaces-0.10 -lgstvideo-$(GST_MAJORMINOR) \
$(GTK_LIBS) $(CAIRO_LIBS)

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@ -0,0 +1,199 @@
/* GStreamer
* Copyright (C) 2011 Jon Nordby <jononor@gmail.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.
*/
/*
* Example showing usage of the cairooverlay element
*
* Note: The example program not run on non-X11 platforms because
* it is using the xvimageoverlay element. That part of the code was
* roughly based on gst_x_overlay documentation.
*/
#include <gst/gst.h>
#include <gst/video/video.h>
#include <gst/interfaces/xoverlay.h>
#include <gtk/gtk.h>
#include <cairo.h>
#include <cairo-gobject.h>
#ifdef GDK_WINDOWING_X11
#include <gdk/gdkx.h>
#endif
static gulong video_window_xid = 0;
static GstBusSyncReply
bus_sync_handler (GstBus * bus, GstMessage * message, gpointer user_data)
{
if (GST_MESSAGE_TYPE (message) != GST_MESSAGE_ELEMENT)
return GST_BUS_PASS;
if (!gst_structure_has_name (message->structure, "prepare-xwindow-id"))
return GST_BUS_PASS;
if (video_window_xid != 0) {
GstXOverlay *xoverlay;
xoverlay = GST_X_OVERLAY (GST_MESSAGE_SRC (message));
gst_x_overlay_set_window_handle (xoverlay, video_window_xid);
} else {
g_warning ("Should have obtained video_window_xid by now!");
}
gst_message_unref (message);
return GST_BUS_DROP;
}
static void
video_widget_realize_cb (GtkWidget * widget, gpointer data)
{
#ifdef GDK_WINDOWING_X11
video_window_xid = GDK_WINDOW_XID (widget->window);
#endif
}
static GtkWidget *
setup_gtk_window (void)
{
GtkWidget *video_window;
GtkWidget *app_window;
app_window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
video_window = gtk_drawing_area_new ();
g_signal_connect (video_window, "realize",
G_CALLBACK (video_widget_realize_cb), NULL);
gtk_widget_set_double_buffered (video_window, FALSE);
gtk_container_add (GTK_CONTAINER (app_window), video_window);
gtk_widget_show_all (app_window);
gtk_widget_realize (app_window);
g_assert (video_window_xid != 0);
return app_window;
}
/* Datastructure to share the state we are interested in between
* prepare and render function. */
typedef struct
{
gboolean valid;
int width;
int height;
} CairoOverlayState;
/* Store the information from the caps that we are interested in. */
static void
prepare_overlay (GstElement * overlay, GstCaps * caps, gpointer user_data)
{
CairoOverlayState *state = (CairoOverlayState *) user_data;
gst_video_format_parse_caps (caps, NULL, &state->width, &state->height);
state->valid = TRUE;
}
/* Draw the overlay.
* This function draws a cute "beating" heart. */
static void
draw_overlay (GstElement * overlay, cairo_t * cr, guint64 timestamp,
guint64 duration, gpointer user_data)
{
CairoOverlayState *s = (CairoOverlayState *) user_data;
double scale;
if (!s->valid)
return;
scale = 2 * (((timestamp / (int) 1e7) % 70) + 30) / 100.0;
cairo_translate (cr, s->width / 2, (s->height / 2) - 30);
cairo_scale (cr, scale, scale);
cairo_move_to (cr, 0, 0);
cairo_curve_to (cr, 0, -30, -50, -30, -50, 0);
cairo_curve_to (cr, -50, 30, 0, 35, 0, 60);
cairo_curve_to (cr, 0, 35, 50, 30, 50, 0);
cairo_curve_to (cr, 50, -30, 0, -30, 0, 0);
cairo_set_source_rgba (cr, 0.9, 0.0, 0.1, 0.7);
cairo_fill (cr);
}
static GstElement *
setup_gst_pipeline (CairoOverlayState * overlay_state)
{
GstElement *pipeline;
GstElement *cairo_overlay;
GstElement *source, *adaptor1, *adaptor2, *sink;
GstBus *bus;
pipeline = gst_pipeline_new ("cairo-overlay-example");
/* Adaptors needed because cairooverlay only supports ARGB data */
source = gst_element_factory_make ("videotestsrc", "source");
adaptor1 = gst_element_factory_make ("ffmpegcolorspace", "adaptor1");
cairo_overlay = gst_element_factory_make ("cairooverlay", "overlay");
adaptor2 = gst_element_factory_make ("ffmpegcolorspace", "adaptor2");
sink = gst_element_factory_make ("xvimagesink", "sink");
/* If failing, the element could not be created */
g_assert (cairo_overlay);
/* Hook up the neccesary signals for cairooverlay */
g_signal_connect (cairo_overlay, "draw",
G_CALLBACK (draw_overlay), overlay_state);
g_signal_connect (cairo_overlay, "caps-changed",
G_CALLBACK (prepare_overlay), overlay_state);
gst_bin_add_many (GST_BIN (pipeline), source, adaptor1,
cairo_overlay, adaptor2, sink, NULL);
if (!gst_element_link_many (source, adaptor1,
cairo_overlay, adaptor2, sink, NULL)) {
g_warning ("Failed to link elements!");
}
bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline));
gst_bus_set_sync_handler (bus, (GstBusSyncHandler) bus_sync_handler, NULL);
gst_object_unref (bus);
return pipeline;
}
int
main (int argc, char **argv)
{
GtkWidget *window;
GstElement *pipeline;
CairoOverlayState *overlay_state;
gtk_init (&argc, &argv);
gst_init (&argc, &argv);
window = setup_gtk_window ();
overlay_state = g_new (CairoOverlayState, 1);
pipeline = setup_gst_pipeline (overlay_state);
gst_element_set_state (pipeline, GST_STATE_PLAYING);
gtk_main ();
gst_object_unref (pipeline);
gtk_widget_destroy (GTK_WIDGET (window));
g_free (overlay_state);
}