If you have OpenCV, it will be easy. Zheng Xing Ph.D Student Hanlon Financial Systems Lab Stevens Institute of Technology <div class="gmail_quote">On Jun 28, 2015 1:22 PM, "yannick inizan" <<a href="mailto:inizan.yannick@gmail.com">inizan.yannick@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div class="gmail_extra">I use playbin element and emit "convert-sample" signal. raw data is converted with GdkPixbuf here an example (in Vala) : <a href="http://pastebin.com/Ex83wP6m" target="_blank">http://pastebin.com/Ex83wP6m</a></div><div class="gmail_extra"> <div class="gmail_quote">2015-06-28 16:49 GMT+02:00 Faran <<a href="mailto:m.faran.majeed@gmail.com" target="_blank">m.faran.majeed@gmail.com</a>>: <blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">I've written the following code to extract video frames but now am stuck. Could anyone please help??? #include <gst/gst.h> #include <gst/app/gstappsrc.h> #include <gst/app/gstappsink.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 ("End of stream\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 sink_pad_add(GstElement *src, GstPad *pad, gpointer data) { g_print("\n This method is called when sink is padded \n"); } static void on_pad_added (GstElement *src, GstPad *new_pad, gpointer data) { GstPad *sink_pad_audio, *sink_pad_video; 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"); sink_pad_audio = gst_element_get_static_pad (decoder, "sink"); //sink_pad_video = gst_element_get_static_pad (decoder, "sink"); gst_pad_link (new_pad, sink_pad_audio); gst_object_unref (sink_pad_audio); } static void image_processing() { g_print("image processing method is called"); } int main (int argc, char *argv[]) { GMainLoop *loop; GstElement *pipeline, *source, *demuxer, *decoder, *conv, *sink; GstElement *video_decoder, *video_conv, *video_sink; GstBus *bus; guint bus_watch_id; GstElementFactory *factory; /* Initialisation */ gst_init (&argc, &argv); loop = g_main_loop_new (NULL, FALSE); /* Check input arguments */ if (argc != 2) { g_printerr ("Usage: %s <Ogg/Vorbis filename>\n", argv[0]); return -1; } /* Create gstreamer elements */ pipeline = gst_pipeline_new ("audio-player"); source = gst_element_factory_make ("filesrc", "source"); demuxer = gst_element_factory_make ("oggdemux", "ogg-demuxer"); video_decoder = gst_element_factory_make ("theoradec","video_decoder"); video_conv = gst_element_factory_make ("videoconvert","video_convert"); video_sink = gst_element_factory_make ("autovideosink","sink"); if(!demuxer){g_print("qtdemuxer is not created");} if(!video_conv){g_print("video converter is not created");} if (!pipeline || !source || !demuxer || !decoder || !conv || !sink || !video_decoder || !video_conv || !video_sink) { g_printerr ("One element could not be created. Exiting.\n"); return -1; } /* Set up the pipeline */ /* we set the input filename to the source element */ g_object_set (G_OBJECT (source), "location", argv[1], NULL); /* we add a message handler */ bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline)); bus_watch_id = gst_bus_add_watch (bus, bus_call, loop); gst_object_unref (bus); /* we add all elements into the pipeline */ /* file-source | ogg-demuxer | vorbis-decoder | converter | alsa-output */ //gst_bin_add_many (GST_BIN (pipeline), source, demuxer, decoder, conv, sink /*,video_decoder, video_conv, video_sink*/, NULL); gst_bin_add_many (GST_BIN (pipeline), source, demuxer, video_decoder, video_conv, video_sink, NULL); /* we link the elements together */ /* file-source -> ogg-demuxer ~> vorbis-decoder -> converter -> alsa-output */ gst_element_link (source, demuxer); //gst_element_link_many (decoder, conv, sink, NULL); for .ogg audio gst_element_link_many (video_decoder, video_conv, video_sink, NULL); // for .ogg video /*if(!gst_element_link_many (video_conv, video_sink, NULL)) { g_print("One of the element is not linking"); }*/ g_signal_connect (demuxer, "pad-added", G_CALLBACK (on_pad_added), video_decoder); g_signal_connect (video_conv, "pad-added", G_CALLBACK(sink_pad_add), video_sink); g_object_connect (video_conv, "pad-added", G_CALLBACK(sink_pad_add), video_sink); /* note that the demuxer will be linked to the decoder dynamically. The reason is that Ogg may contain various streams (for example audio and video). The source pad(s) will be created at run time, by the demuxer when it detects the amount and nature of streams. Therefore we connect a callback function which will be executed when the "pad-added" is emitted.*/ /* Set the pipeline to "playing" state*/ g_print ("Now playing: %s\n", argv[1]); gst_element_set_state (pipeline, GST_STATE_PLAYING); /* Iterate */ g_print ("Running...\n"); gchar *name; g_object_get(G_OBJECT (video_sink), "name", &name, NULL); factory = gst_element_factory_find ("autovideosink"); g_print("The name of video_sink is %s \n", name); g_print ("The '%s' element is a member of the category %s.\n" "Description: %s\n", gst_plugin_feature_get_name (GST_PLUGIN_FEATURE (factory)), gst_element_factory_get_metadata (factory, GST_ELEMENT_METADATA_KLASS), gst_element_factory_get_metadata (factory, GST_ELEMENT_METADATA_DESCRIPTION)); GstPad *pad = gst_element_get_static_pad(video_sink, name); //name = gst_pad_get_name (pad); g_print ("A new pad %s was created\n", name); g_free (name); GstCaps *c = gst_pad_get_pad_template_caps(pad); g_print("Th structure is %c", c); GstSample *sample; g_signal_emit_by_name (video_sink, "pull-sample", sample); GstCaps *caps = gst_sample_get_caps(sample); GstBuffer *buffer = gst_sample_get_buffer (sample); //buffer = gst_app_sink_pull_buffer(pro->sink) GstMapInfo map; gst_buffer_map (buffer, &map, GST_MAP_READ); gint width, height; const GstStructure *str; str = gst_caps_get_structure (caps, 0); gst_structure_get_int (str, "width", &width); gst_structure_get_int (str, "height", &height); g_print("The width is = %d", width); g_print("The height is = %d", height); cv::Mat frame(cv::Size(width, height), CV_8UC3, (char*)map.data, -3); cv::imwrite("Test2.jpg", frame); GstElement *rsink = gst_bin_get_by_name( GST_BIN( pipeline ), "sink" ); GstSample *pstGstSample1; // pstGstSample1 = gst_app_sink_pull_sample( (GstAppSink *)rsink); //image_processing(pstGstSample1); g_main_loop_run (loop); /* Out of the main loop, clean up nicely */ g_print ("Returned, stopping playback\n"); gst_element_set_state (pipeline, GST_STATE_NULL); GST_DEBUG_BIN_TO_DOT_FILE(GST_BIN(pipeline), GST_DEBUG_GRAPH_SHOW_ALL ,"/home/siraj/Desktop/myplayer"); g_print ("Deleting pipeline\n"); gst_object_unref (GST_OBJECT (pipeline)); g_source_remove (bus_watch_id); g_main_loop_unref (loop); return 0; } -- View this message in context: <a href="http://gstreamer-devel.966125.n4.nabble.com/How-to-extract-video-frames-from-pipeline-through-gstreamer-1-0-tp4672495.html" rel="noreferrer" target="_blank">http://gstreamer-devel.966125.n4.nabble.com/How-to-extract-video-frames-from-pipeline-through-gstreamer-1-0-tp4672495.html</a> Sent from the GStreamer-devel mailing list archive at Nabble.com. _______________________________________________ gstreamer-devel mailing list <a href="mailto:gstreamer-devel@lists.freedesktop.org" target="_blank">gstreamer-devel@lists.freedesktop.org</a> <a href="http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" rel="noreferrer" target="_blank">http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a> </blockquote></div> </div></div> _______________________________________________ gstreamer-devel mailing list <a href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.freedesktop.org</a> <a href="http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" rel="noreferrer" target="_blank">http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a> </blockquote></div>