h.264 - Playing RTSP with python-gstreamer -

i use gstreamer playing rtsp stream ip cameras (like axis.) use command line this:

gst-launch-0.10 rtspsrc location=rtsp://192.168.0.127/axis-media/media.amp latency=0 ! decodebin ! autovideosink 

and work fine.

i want control gui in pygtk use gstreamer python bindings. i've wrote piece of code:

[...] self.player = gst.pipeline("player") source = gst.element_factory_make("rtspsrc", "source") source.set_property("location", "rtsp://192.168.0.127/axis-media/media.amp") decoder = gst.element_factory_make("decodebin", "decoder") sink = gst.element_factory_make("autovideosink", "sink")  self.player.add(source, decoder, sink) gst.element_link_many(source, decoder, sink)  bus = self.player.get_bus() bus.add_signal_watch() bus.enable_sync_message_emission() bus.connect("message", self.on_message) bus.connect("sync-message::element", self.on_sync_message) [...] 

but doesn't work , quit message:

gst.element_link_many(source, decoder,sink) gst.linkerror: failed link source decoder 

i've try improve cli use h264:

gst-launch-0.10 -v rtspsrc location=rtsp://192.168.0.127/axis-media/media.amp ! rtph264depay !  ffdec_h264 ! xvimagesink 

and implement in python code that:

[...] self.player = gst.pipeline("player") source = gst.element_factory_make("rtspsrc", "source") depay = gst.element_factory_make("rtph264depay", "depay") decoder = gst.element_factory_make("ffdec_h264", "decoder") sink = gst.element_factory_make("xvimagesink", "output")  self.player.add(source, depay, decoder, sink) gst.element_link_many(source, depay, decoder, sink) [...] 

but got same error :(

gst.linkerror: failed link source depay 

there wrong between source (rtspsrc), work decodebin filesrc (don't work of course rtph264depay)

i don't understand why doesn't work because work in cli. experts of gstreamer can me ?

thanks in advance.

regards,

i have "c" implementation of code looking for. think should simple convert "python"

 //display rtsp streaming of video  //(c) 2011 enthusiasticgeek  // code distributed in hope useful,  // without warranty; without implied warranty of  // merchantability or fitness particular purpose.    #include <string.h> #include <math.h> #include <gst/gst.h> #include <glib.h>  static gboolean bus_call (gstbus *bus,gstmessage *msg, gpointer data){   gmainloop *loop = (gmainloop *) data;    switch (gst_message_type (msg)) {      case gst_message_eos:       g_print ("stream ends\n");       g_main_loop_quit (loop);       break;      case gst_message_error: {       gchar  *debug;       gerror *error;        gst_message_parse_error (msg, &error, &debug);       g_free (debug);        g_printerr ("error: %s\n", error->message);       g_error_free (error);        g_main_loop_quit (loop);       break;     }     default:       break;   }    return true; }  static void on_pad_added (gstelement *element, gstpad *pad, gpointer data){    gstpad *sinkpad;   gstelement *decoder = (gstelement *) data;    /* can link pad rtsp-decoder sink pad */   g_print ("dynamic pad created, linking source/demuxer\n");    sinkpad = gst_element_get_static_pad (decoder, "sink");    gst_pad_link (pad, sinkpad);    gst_object_unref (sinkpad); }  int main (int argc, char *argv[]) {   gmainloop *loop;   gstbus *bus;   gstelement *source;   gstelement *decoder;   gstelement *sink;   gstelement *pipeline;   gstelement *demux;   gstelement *colorspace;    /* initializing gstreamer */   gst_init (&argc, &argv);   loop = g_main_loop_new (null, false);   //gst-launch-0.10 rtspsrc location=rtsp://<ip> ! decodebin ! ffmpegcolorspace ! autovideosink  //gst-launch -v rtspsrc location="rtsp://<ip> ! rtpmp4vdepay ! mpeg4videoparse ! ffdec_mpeg4 ! ffmpegcolorspace! autovideosink  //gst-launch -v rtspsrc location="rtsp://<ip> ! rtpmp4vdepay ! ffdec_mpeg4 ! ffmpegcolorspace! autovideosink   /* create pipe's elements */   pipeline = gst_pipeline_new ("video player");   g_assert (pipeline);   source   = gst_element_factory_make ("rtspsrc", "source");   g_assert (source);   demux = gst_element_factory_make ("rtpmp4vdepay", "depay");   g_assert (demux);   decoder = gst_element_factory_make ("ffdec_mpeg4", "decoder");   g_assert (decoder);   colorspace     = gst_element_factory_make ("ffmpegcolorspace",  "colorspace");   g_assert(colorspace);   sink     = gst_element_factory_make ("autovideosink", "output");   g_assert (sink);    /*make sure: every elements created ok*/   if (!pipeline || !source || !demux || !decoder || !colorspace || !sink) {     g_printerr ("one of elements wasn't create... exiting\n");     return -1;   }    g_printf(" \npipeline part(a) ->(dynamic/runtime link)  part(b)[ part(b-1) -> part(b-2) -> part(b-3) ]\n\n");   g_printf(" [source](dynamic)->(dynamic)[demux]->[decoder]->[colorspace]->[videosink] \n\n");    /* set video source */   g_object_set (g_object (source), "location", argv[1], null);   //g_object_set (g_object (source), "do-rtcp", true, null);   g_object_set (g_object (source), "latency", 0, null);    /* putting message handler */   bus = gst_pipeline_get_bus (gst_pipeline (pipeline));   gst_bus_add_watch (bus, bus_call, loop);   gst_object_unref (bus);    /* add elements bin */   gst_bin_add_many (gst_bin (pipeline), source, demux, decoder, colorspace, sink, null);    /* link confirmation */   if (!gst_element_link_many (demux, decoder, colorspace, sink, null)){      g_warning ("linking part (b) fail...");   }    g_printf("\nnote source linked demuxer(depayload) dynamically.\n\      reason rtspsrc may contain various elements (for example\n\      audio , video). source pad(s) created @ run time,\n\      rtspsrc when detects amount , nature of elements.\n\      therefore connect callback function executed\n\      when \"pad-added\" emitted.\n");    /* dynamic pad creation */   if(! g_signal_connect (source, "pad-added", g_callback (on_pad_added),demux))   {     g_warning ("linking part (a) part (b) fail...");   }   /* run pipeline */   g_print ("playing: %s\n", argv[1]);   gst_element_set_state (pipeline, gst_state_playing);   g_main_loop_run (loop);    /* ending playback */   g_print ("end of streaming... ending playback\n");   gst_element_set_state (pipeline, gst_state_null);    /* eliminating pipeline */   g_print ("eliminating pipeline\n");   gst_object_unref (gst_object (pipeline));    return 0; } 

makefile

test = test12 ext = c cc = gcc cpp = g++ gstreamer:     $(cc) -g $(test).$(ext) -o $(test) `pkg-config gstreamer-0.10 --libs --cflags` `pkg-config gtk+-2.0 --libs --cflags` clean:     rm -rf $(test) 

update

equivalent java code

 // display rtsp streaming of video  // (c) 2011 enthusiasticgeek  // code distributed in hope useful,  // without warranty; without implied warranty of  // merchantability or fitness particular purpose  // leave credits intact  package video2; //replace package import java.awt.borderlayout; import java.awt.dimension;  import javax.swing.jframe; import javax.swing.swingutilities;  //import org.gstreamer.caps; import org.gstreamer.element; import org.gstreamer.elementfactory; import org.gstreamer.gst; import org.gstreamer.pad; import org.gstreamer.paddirection; import org.gstreamer.pipeline; import org.gstreamer.swing.videocomponent;  /**  * simple videotest example.  */ public class main {     public main() {     }     private static pipeline pipe;     public static void main(string[] args) {     // quartz abysmally slow @ scaling video reason, turn off.     system.setproperty("apple.awt.graphics.usequartz", "false");      args = gst.init("swingvideotest", args);      pipe = new pipeline("pipeline");     /*     final element videosrc = elementfactory.make("videotestsrc", "source");     final element videofilter = elementfactory.make("capsfilter", "flt");     videofilter.setcaps(caps.fromstring("video/x-raw-yuv, width=720, height=576"             + ", bpp=32, depth=32, framerate=25/1"));     */       pipe.getbus().connect(new bus.error() {         public void errormessage(gstobject source, int code, string message) {             system.out.println("error occurred: " + message);             gst.quit();         }     });     pipe.getbus().connect(new bus.state_changed() {         public void statechanged(gstobject source, state old, state current, state pending) {             if (source == pipe) {                 system.out.println("pipeline state changed " + old + " " + current);             }         }     });     pipe.getbus().connect(new bus.eos() {         public void endofstream(gstobject source) {             system.out.println("finished playing file");             gst.quit();         }     });               pipe.getbus().connect(new bus.tag() {         public void tagsfound(gstobject source, taglist taglist) {             (string tag : taglist.gettagnames()) {                 system.out.println("found tag " + tag + " = "                         + taglist.getvalue(tag, 0));             }         }     });      final element source = elementfactory.make("rtspsrc", "source");     final element demux = elementfactory.make("rtpmp4vdepay", "depay");     final element decoder=elementfactory.make("ffdec_mpeg4", "decoder");     final element colorspace = elementfactory.make("ffmpegcolorspace",  "colorspace");     //final element sink = elementfactory.make ("autovideosink", "output");      swingutilities.invokelater(new runnable() {          public void run() {             // create video component , link in             videocomponent videocomponent = new videocomponent();             element videosink = videocomponent.getelement();             source.connect(new element.pad_added() {            public void padadded(element element, pad pad) {             pad.link(demux.getstaticpad("sink"));            }             });             pad p = new pad(null, paddirection.src);            source.addpad(p);              source.set("location","rtsp://<user>:<pass>@<ip>/mpeg4/1/media.amp");  //replace source              pipe.addmany(source, demux, decoder, colorspace, videosink);             element.linkmany(demux, decoder, colorspace, videosink);              // create jframe display video output             jframe frame = new jframe("swing video test");             frame.setdefaultcloseoperation(jframe.exit_on_close);             frame.add(videocomponent, borderlayout.center);             videocomponent.setpreferredsize(new dimension(720, 576));             frame.pack();             frame.setvisible(true);              // start pipeline processing             pipe.play();         }     });     } }