gstreamer/tests/examples/controller/audio-example.c
2014-08-07 14:54:37 +01:00

95 lines
2.7 KiB
C

/*
* audio-example.c
*
* Builds a pipeline with [ audiotestsource ! autoaudiosink ] and sweeps
* frequency and volume.
*
* Needs gst-plugins-base + gst-plugins-good installed.
*/
#include <gst/gst.h>
#include <gst/controller/gstinterpolationcontrolsource.h>
#include <gst/controller/gstdirectcontrolbinding.h>
gint
main (gint argc, gchar ** argv)
{
gint res = 1;
GstElement *src, *sink;
GstElement *bin;
GstControlSource *cs1, *cs2;
GstTimedValueControlSource *tvcs;
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 ("audiotestsrc", NULL);
if (!src) {
GST_WARNING ("need audiotestsrc from gst-plugins-base");
goto Error;
}
sink = gst_element_factory_make ("autoaudiosink", NULL);
if (!sink) {
GST_WARNING ("need autoaudiosink from gst-plugins-good");
goto Error;
}
gst_bin_add_many (GST_BIN (bin), src, sink, NULL);
if (!gst_element_link (src, sink)) {
GST_WARNING ("can't link elements");
goto Error;
}
/* setup control sources */
cs1 = gst_interpolation_control_source_new ();
cs2 = gst_interpolation_control_source_new ();
gst_object_add_control_binding (GST_OBJECT_CAST (src),
gst_direct_control_binding_new (GST_OBJECT_CAST (src), "volume", cs1));
gst_object_add_control_binding (GST_OBJECT_CAST (src),
gst_direct_control_binding_new (GST_OBJECT_CAST (src), "freq", cs2));
/* set interpolation mode */
g_object_set (cs1, "mode", GST_INTERPOLATION_MODE_LINEAR, NULL);
g_object_set (cs2, "mode", GST_INTERPOLATION_MODE_LINEAR, NULL);
/* set control values */
tvcs = (GstTimedValueControlSource *) cs1;
gst_timed_value_control_source_set (tvcs, 0 * GST_SECOND, 0.0);
gst_timed_value_control_source_set (tvcs, 5 * GST_SECOND, 1.0);
gst_object_unref (cs1);
tvcs = (GstTimedValueControlSource *) cs2;
gst_timed_value_control_source_set (tvcs, 0 * GST_SECOND, 220.0 / 20000.0);
gst_timed_value_control_source_set (tvcs, 3 * GST_SECOND, 3520.0 / 20000.0);
gst_timed_value_control_source_set (tvcs, 6 * GST_SECOND, 440.0 / 20000.0);
gst_object_unref (cs2);
/* run for 7 seconds */
clock_id =
gst_clock_new_single_shot_id (clock,
gst_clock_get_time (clock) + (7 * 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 (clock);
gst_object_unref (bin);
res = 0;
Error:
return (res);
}