GStreamer error : Gstreamer encountered a general stream error - gstreamer

Question

I am working gstreamer for iOS, but having error with demux.
It says "Eror received from element matroskademux0 : Gstreamer encountered a general stream error".
Here is the soure code.
GstBus *bus;
GSource *bus_source;
GstElement *source1, *clrspace1, *clrspace2, *clrspace, *videobox1, *sink, *source2, *mpegenc, *avimux;
GstElement *videomixer;
GstElement *decodebin1, *decodebin2;
GstElement *queue;
/* Build pipeline */
pipeline = gst_pipeline_new("pipelinecomposer");
source1 = gst_element_factory_make("filesrc", "source1");
source2 = gst_element_factory_make("filesrc", "source2");
videobox1 = gst_element_factory_make("videobox", "videobox");
videomixer = gst_element_factory_make("videomixer", "videomixer");
clrspace1 = gst_element_factory_make("videoconvert", "clrspace1");
clrspace2 = gst_element_factory_make("videoconvert", "clrspace2");
clrspace = gst_element_factory_make("videoconvert", "clrspace");
sink = gst_element_factory_make("filesink", "sink");
mpegenc = gst_element_factory_make("x264enc", "mpegenc");
avimux = gst_element_factory_make("mpegtsmux", "avimux");
decodebin1 = gst_element_factory_make("decodebin", "decodebin1");
decodebin2 = gst_element_factory_make("decodebin", "decodebin2");
queue = gst_element_factory_make("queue", "queue");
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *filePath = [NSString stringWithFormat:#"%#/%#", documentsDirectory, #"1.avi"];
NSString *filePath_1 = [NSString stringWithFormat:#"%#", #"/Users/john/Movies/1.webm"];
NSString *filePath_2 = [NSString stringWithFormat:#"%#", #"/Users/john/Movies/2.webm"];
g_object_set (G_OBJECT (source1), "location", [filePath_1 UTF8String], NULL);
g_object_set (G_OBJECT (source2), "location", [filePath_2 UTF8String], NULL);
g_object_set (G_OBJECT (sink), "location", [filePath UTF8String], NULL);
g_object_set(videobox1,"border-alpha",0,"top",0,"left",0,NULL);
gst_bin_add_many(GST_BIN (pipeline), source1, sink, videobox1, videomixer, clrspace1, clrspace2, clrspace, source2, mpegenc, avimux, decodebin1, decodebin2, nil);
gst_element_link_many(source1, decodebin1, clrspace1, videobox1, videomixer, clrspace, mpegenc, avimux, sink, nil);
gst_element_link_many(source2, decodebin2, clrspace2, videomixer, nil);
gst_element_set_state(pipeline, GST_STATE_PLAYING);
Please help me.
Hello guys,
solved problem.
I have to use pad for filesrc.
Here is the modified source codes.
static void on_pad_added (GstElement *element, GstPad *pad, gpointer data)
{
GstPad *sinkpad;
GstElement *decoder = (GstElement *) data;
/* We can now link this pad with the vorbis-decoder sink pad */
g_print ("Dynamic pad created, linking demuxer/decoder\n");
sinkpad = gst_element_get_static_pad (decoder, "sink");
gst_pad_link (pad, sinkpad);
gst_object_unref (sinkpad);
}
/* Main method for the bus monitoring code */
-(void) app_function
{
GstBus *bus;
GSource *bus_source;
GstElement *source1, *clrspace1, *clrspace2, *clrspace, *videobox1, *sink, *source2, *mpegenc, *avimux;
GstElement *videomixer;
GstElement *decodebin1, *decodebin2;
GstElement *matroskademux1, *vp8dec1;
GST_DEBUG ("Creating pipeline");
/* Create our own GLib Main Context and make it the default one */
context = g_main_context_new ();
g_main_context_push_thread_default(context);
/* Build pipeline */
pipeline = gst_pipeline_new("pipelinecomposer");
source1 = gst_element_factory_make("filesrc", "source1");
source2 = gst_element_factory_make("filesrc", "source2");
videobox1 = gst_element_factory_make("videobox", "videobox");
videomixer = gst_element_factory_make("videomixer", "videomixer");
clrspace1 = gst_element_factory_make("videoconvert", "clrspace1");
clrspace2 = gst_element_factory_make("videoconvert", "clrspace2");
clrspace = gst_element_factory_make("videoconvert", "clrspace");
sink = gst_element_factory_make("filesink", "sink");
mpegenc = gst_element_factory_make("x264enc", "mpegenc");
avimux = gst_element_factory_make("mpegtsmux", "avimux");
decodebin1 = gst_element_factory_make("decodebin", "decodebin1");
decodebin2 = gst_element_factory_make("decodebin", "decodebin2");
matroskademux1 = gst_element_factory_make("matroskademux", "matroskademux1");
vp8dec1 = gst_element_factory_make("vp8dec", "vp8dec1");
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *filePath = [NSString stringWithFormat:#"%#/%#", documentsDirectory, #"1.avi"];
NSString *filePath_1 = [NSString stringWithFormat:#"%#", #"/Users/johanbasore1/Movies/1.webm"];
NSString *filePath_2 = [NSString stringWithFormat:#"%#", #"/Users/johanbasore1/Movies/2.webm"];
g_object_set (G_OBJECT (source1), "location", [filePath_1 UTF8String], NULL);
g_object_set (G_OBJECT (source2), "location", [filePath_2 UTF8String], NULL);
g_object_set (G_OBJECT (sink), "location", [filePath UTF8String], NULL);
g_object_set(videobox1,"border-alpha",0,"top",0,"left",0,NULL);
g_signal_connect(matroskademux1, "pad-added", G_CALLBACK(on_pad_added), vp8dec1);
gst_bin_add_many(GST_BIN (pipeline), source1, matroskademux1, vp8dec1 , sink, clrspace1, mpegenc, avimux, nil);
gst_element_link(source1, matroskademux1);
gst_element_link_many(vp8dec1, clrspace1, mpegenc, avimux, sink, nil);
}