<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type"> <title></title> </head> <body bgcolor="#ffffff" text="#000000"> On 10/25/2011 08:06 AM, Rossana Guerra wrote: <blockquote cite="mid:CAAMjx-fTwirkrZUcbswN8xt2=fqbMK+z3G=2Ww5VufLQPqscWw@mail.gmail.com" type="cite">Hello everyone, I am translating the following code to C/C++: <a moz-do-not-send="true" href="http://notes.brooks.nu/2011/01/python-gstreamer-controller/">http://notes.brooks.nu/2011/01/python-gstreamer-controller/</a> It's a controller for controlling the alpha channel during crossfade, I adapted it for transitions, using, smpte instead. </blockquote> smptealpha does not have a property called "alpha". Only "border" and "invert" are controllable right now. Stefan <blockquote cite="mid:CAAMjx-fTwirkrZUcbswN8xt2=fqbMK+z3G=2Ww5VufLQPqscWw@mail.gmail.com" type="cite"> The fact is it returns NULL and the programs stop running. The code is below, I appreciate any suggestion. I am a bit clueless is an adaptation of a code I did before and it works. Thanks and regards. Rossana //// the code #include <gst.h> #include <controller/gstcontroller.h> #include <iostream> using namespace std; // Manejador de errores static gboolean bus_call (GstBus *bus, GstMessage *msg, gpointer data) { ::::::::::::::::::::::::................ } static void on_pad_added (GstElement *element, GstPad *pad, gpointer  data) {   GstPad *sinkpad = NULL;   GstElement * elemento = (GstElement *) data;   /* Ahora linkeo el pad de comp con sink pad */   g_print ("Dynamic pad created, linking queue\n");   sinkpad = gst_element_get_static_pad (elemento, "sink");   gst_pad_link (pad, sinkpad);   gst_object_unref(sinkpad); } int main(int argc, char *argv[]) {   GMainLoop *loop = NULL;   GstElement *src1, *src2,*dec1,*dec2,*alfa1,*color,*smpte,*queue,*sink;   GstBus *bus;   gdouble duracion = 500;   gint transicion = 1;   cout << "Inicio..." << endl;     /* init GStreamer */   gst_init (&argc, &argv);   gst_controller_init (&argc, &argv);   loop = g_main_loop_new (NULL, FALSE);    /* make sure we have input */   if (argc != 3) {     g_print ("Usage: %s <filename1> <filename2>\n", argv[0]);     return -1;   }     src1 = gst_element_factory_make("filesrc", "src1");   g_object_set(G_OBJECT(src1),"location",argv[1], NULL);   src2 = gst_element_factory_make("filesrc", "src2");   g_object_set(G_OBJECT(src1),"location",argv[2], NULL);   GstElement *pipeline = gst_pipeline_new ("video-player");   dec1 = gst_element_factory_make("decodebin2","dec1");   dec2 = gst_element_factory_make("decodebin2","dec2");   bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline));   gst_bus_add_watch (bus, bus_call, loop);   gst_object_unref (bus);   alfa1   = gst_element_factory_make ("alpha","alfa1");   smpte  = gst_element_factory_make ("smptealpha","smpte");   color  = gst_element_factory_make ("ffmpegcolorspace", "color");   GstElement * mixer  = gst_element_factory_make("videomixer", "mixer");   if ((!alfa1) || (!smpte) || (!color) || (!mixer))   {       g_printerr ("Alguno de los elementos del Bin no pudo ser creado. Saliendo\n");      return 0;   }   queue = gst_element_factory_make("queue", "queue");   sink  = gst_element_factory_make("autovideosink", "sink");   cout << "Creando 1..." << endl;   // Agrego Controlador   GstController * ctrl = NULL;   if (!(ctrl = gst_controller_new (G_OBJECT(smpte), "alpha",NULL)))  /// Here's the error, always return NULL   {         cout << "ctrl value..." << ctrl << endl;                 GST_WARNING ("No puede controlar el elemento fuente\n");         return 1;   } </blockquote> <blockquote cite="mid:CAAMjx-fTwirkrZUcbswN8xt2=fqbMK+z3G=2Ww5VufLQPqscWw@mail.gmail.com" type="cite">   // Todo valor GValue debe inicializarse en 0   GValue val_double = { 0, };   g_value_init (&val_double, G_TYPE_DOUBLE);   // Creo la fuente al controlador y la asocio al controlador   // Seteo modo de interpolacion   GstInterpolationControlSource * csource = gst_interpolation_control_source_new();   gst_controller_set_control_source (ctrl, "alpha", GST_CONTROL_SOURCE (csource));   gst_interpolation_control_source_set_interpolation_mode(csource,GST_INTERPOLATE_LINEAR);   // Seteo primer valor   g_value_set_double(&val_double, 0.0);   gst_interpolation_control_source_set(csource,(0 * GST_MSECOND),&val_double);   // Seteo segundo valor   g_value_set_double (&val_double, duracion);   gst_interpolation_control_source_set(csource,(1 * GST_MSECOND),&val_double);   g_object_unref (csource);   gst_bin_add_many (GST_BIN (pipeline),src1, src2, dec1, dec2, alfa1, smpte, mixer, queue, color, sink, NULL);   g_signal_connect (G_OBJECT (dec1), "pad-added", G_CALLBACK (on_pad_added),alfa1);   g_signal_connect (G_OBJECT (dec2), "pad-added", G_CALLBACK (on_pad_added),smpte);   gst_element_link (src1,dec1);   gst_element_link (src2,dec2);   gst_element_link (alfa1,mixer);   gst_element_link (smpte,mixer);   gst_element_link (mixer,queue);   gst_element_link (queue,sink);   g_object_set(smpte,"type", transicion, NULL);   /* now run */   gst_element_set_state (pipeline, GST_STATE_PLAYING);   cout << "Playing..." << endl;   g_main_loop_run (loop);     /* also clean up */   gst_element_set_state (pipeline, GST_STATE_NULL);   gst_object_unref (GST_OBJECT (pipeline));   return 0; } <pre wrap=""> <fieldset class="mimeAttachmentHeader"></fieldset> _______________________________________________ gstreamer-devel mailing list <a class="moz-txt-link-abbreviated" href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.freedesktop.org</a> <a class="moz-txt-link-freetext" href="http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel">http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a> </pre> </blockquote> </body> </html>