Add the void_source filter that generates silence.

build/android/basedescs.h

@@ -2,12 +2,14 @@
 
 extern MSFilterDesc ms_tee_desc;
 extern MSFilterDesc ms_join_desc;
+extern MSFilterDesc ms_void_source_desc;
 extern MSFilterDesc ms_void_sink_desc;
  
 
 MSFilterDesc * ms_base_filter_descs[]={
 &ms_tee_desc,
 &ms_join_desc,
+&ms_void_source_desc,
 &ms_void_sink_desc,
 NULL
 };

build/iphone/basedescs.h

@@ -2,6 +2,7 @@
 
 extern MSFilterDesc ms_tee_desc;
 extern MSFilterDesc ms_join_desc;
+extern MSFilterDesc ms_void_source_desc;
 extern MSFilterDesc ms_void_sink_desc;
 extern MSFilterDesc ms_itc_source_desc;
 extern MSFilterDesc ms_itc_sink_desc;
@@ -9,6 +10,7 @@ extern MSFilterDesc ms_itc_sink_desc;
 MSFilterDesc * ms_base_filter_descs[]={
 &ms_tee_desc,
 &ms_join_desc,
+&ms_void_source_desc,
 &ms_void_sink_desc,
 &ms_itc_source_desc,
 &ms_itc_sink_desc,

include/mediastreamer2/allfilters.h

@@ -81,6 +81,7 @@ typedef enum MSFilterId{
 	MS_H263_OLD_ENC_ID,
 	MS_MIRE_ID,
 	MS_VFW_ID,
+	MS_VOID_SOURCE_ID,
 	MS_VOID_SINK_ID,
 	MS_DSCAP_ID,
 	MS_AQ_READ_ID,

src/otherfilters/void.c

@@ -18,8 +18,58 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */
 
 #include "mediastreamer2/msfilter.h"
+#include "mediastreamer2/msticker.h"
 
 
+struct VoidSourceState {
+	int rate;
+	int nchannels;
+};
+
+typedef struct VoidSourceState VoidSourceState;
+
+
+static void void_source_init(MSFilter *f) {
+	VoidSourceState *s = (VoidSourceState *)ms_new(VoidSourceState, 1);
+	s->rate = 8000;
+	s->nchannels = 1;
+	f->data = s;
+}
+
+static void void_source_uninit(MSFilter *f) {
+	ms_free(f->data);
+}
+
+static void void_source_process(MSFilter *f) {
+	mblk_t *m;
+	VoidSourceState *s = (VoidSourceState *)f->data;
+	int nsamples;
+
+	nsamples = (f->ticker->interval * s->rate) / 1000;
+	m = allocb(nsamples * s->nchannels * 2, 0);
+	memset(m->b_wptr, 0, nsamples * s->nchannels * 2);
+	m->b_wptr += nsamples * s->nchannels * 2;
+	ms_queue_put(f->outputs[0], m);
+}
+
+static int void_source_set_rate(MSFilter *f, void *arg) {
+	VoidSourceState *s = (VoidSourceState *)f->data;
+	s->rate = *((int*)arg);
+	return 0;
+}
+
+static int void_source_set_nchannels(MSFilter *f, void *arg) {
+	VoidSourceState *s = (VoidSourceState *)f->data;
+	s->nchannels = *(int *)arg;
+	return 0;
+}
+
+MSFilterMethod void_source_methods[] = {
+	{ MS_FILTER_SET_SAMPLE_RATE, void_source_set_rate },
+	{ MS_FILTER_SET_NCHANNELS, void_source_set_nchannels },
+	{ 0, NULL }
+};
+
 static void void_sink_process(MSFilter *f){
 	mblk_t *im;
 	while((im=ms_queue_get(f->inputs[0]))!=NULL){
@@ -29,6 +79,23 @@ static void void_sink_process(MSFilter *f){
 
 #ifdef _MSC_VER
 
+MSFilterDesc ms_void_source_desc={
+	MS_VOID_SOURCE_ID,
+	"MSVoidSource",
+	N_("A filter that generates silence on its output (useful for beginning some graphs)."),
+	MS_FILTER_OTHER,
+	NULL,
+	0,
+	1,
+	void_source_init,
+	NULL,
+	void_source_process,
+	NULL,
+	void_source_uninit,
+	void_source_methods,
+	MS_FILTER_IS_PUMP
+};
+
 MSFilterDesc ms_void_sink_desc={
 	MS_VOID_SINK_ID,
 	"MSVoidSink",
@@ -46,6 +113,20 @@ MSFilterDesc ms_void_sink_desc={
 
 #else
 
+MSFilterDesc ms_void_source_desc={
+	.id=MS_VOID_SOURCE_ID,
+	.name="MSVoidSource",
+	.text=N_("A filter that generates silence on its output (useful for beginning some graphs)."),
+	.category=MS_FILTER_OTHER,
+	.ninputs=0,
+	.noutputs=1,
+	.init=void_source_init,
+	.process=void_source_process,
+	.uninit=void_source_uninit,
+	.methods=void_source_methods,
+	.flags=MS_FILTER_IS_PUMP
+};
+
 MSFilterDesc ms_void_sink_desc={
 	.id=MS_VOID_SINK_ID,
 	.name="MSVoidSink",
@@ -58,4 +139,5 @@ MSFilterDesc ms_void_sink_desc={
 
 #endif
 
+MS_FILTER_DESC_EXPORT(ms_void_source_desc)
 MS_FILTER_DESC_EXPORT(ms_void_sink_desc)