gstreamer/tests/examples/controller/absolute-example.c

98 lines
2.7 KiB
C
Raw Normal View History

/*
* text-color-example.c
*
* Builds a pipeline with [videotestsrc ! textoverlay ! ximagesink] and
* moves text
*
* Needs gst-plugins-base installed.
*/
#include <gst/gst.h>
#include <gst/controller/gstinterpolationcontrolsource.h>
#include <gst/controller/gstlfocontrolsource.h>
#include <gst/controller/gstargbcontrolbinding.h>
#include <gst/controller/gstdirectcontrolbinding.h>
gint
main (gint argc, gchar ** argv)
{
gint res = 1;
GstElement *src, *text, *sink;
GstElement *bin;
GstControlSource *cs;
GstClock *clock;
GstClockID clock_id;
GstClockReturn wait_ret;
gst_init (&argc, &argv);
/* build pipeline */
bin = gst_pipeline_new ("pipeline");
clock = gst_pipeline_get_clock (GST_PIPELINE (bin));
src = gst_element_factory_make ("videotestsrc", NULL);
if (!src) {
GST_WARNING ("need videotestsrc from gst-plugins-base");
goto Error;
}
g_object_set (src, "pattern", /* red */ 4,
NULL);
text = gst_element_factory_make ("textoverlay", NULL);
if (!text) {
GST_WARNING ("need textoverlay from gst-plugins-base");
goto Error;
}
g_object_set (text,
"text", "GStreamer rocks!",
"font-desc", "Sans, 30",
"xpos", 0.0, "wrap-mode", -1, "halignment", /* position */ 4,
"valignment", /* position */ 3,
NULL);
sink = gst_element_factory_make ("ximagesink", NULL);
if (!sink) {
GST_WARNING ("need ximagesink from gst-plugins-base");
goto Error;
}
gst_bin_add_many (GST_BIN (bin), src, text, sink, NULL);
if (!gst_element_link_many (src, text, sink, NULL)) {
GST_WARNING ("can't link elements");
goto Error;
}
/* setup control sources */
cs = gst_interpolation_control_source_new ();
gst_object_add_control_binding (GST_OBJECT_CAST (text),
gst_direct_control_binding_new_absolute (GST_OBJECT_CAST (text), "deltax",
cs));
g_object_set (cs, "mode", GST_INTERPOLATION_MODE_LINEAR, NULL);
// At second 0 the text will be at 0px on the x-axis
gst_timed_value_control_source_set ((GstTimedValueControlSource *) cs, 0, 0);
// At second 5 the text will be at 1000px on the x-axis
gst_timed_value_control_source_set ((GstTimedValueControlSource *) cs,
GST_SECOND * 5, 1000);
gst_object_unref (cs);
/* run for 10 seconds */
clock_id =
gst_clock_new_single_shot_id (clock,
gst_clock_get_time (clock) + (10 * GST_SECOND));
if (gst_element_set_state (bin, GST_STATE_PLAYING)) {
if ((wait_ret = gst_clock_id_wait (clock_id, NULL)) != GST_CLOCK_OK) {
GST_WARNING ("clock_id_wait returned: %d", wait_ret);
}
gst_element_set_state (bin, GST_STATE_NULL);
}
/* cleanup */
gst_clock_id_unref (clock_id);
gst_object_unref (G_OBJECT (clock));
gst_object_unref (G_OBJECT (bin));
res = 0;
Error:
return (res);
}