[gst-devel] How to concatenate video files

[Stefan v. Wachter]

Hi all,

maybe this solution can help somebody else:
I compiled the gnonlin sources on WinXP using MSVC Express 2008 without 
major problems. With libgstgnonlin.dll the following c code works to 
concatenate 2 video files which are given as command line arguments:

BTW: Why don't you distribute the gnonlin binaries along with the other 
win32 binaries?

Thanks a lot for your work on gstreamer!
Stefan

#include <stdio.h>
#include <tchar.h>
#include <gst/gst.h>

GstElement *pipeline, *conv, *sink, *comp, *gnlfilesource1, *gnlfilesource2;

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 *err;

            gst_message_parse_error (msg, &err, &debug);
            g_free (debug);

            g_print ("Error: %s\n", err->message);
            g_error_free (err);

            g_main_loop_quit (loop);
            break;
        }
        case GST_MESSAGE_STATE_CHANGED: {
            g_print ("GST_MESSAGE_STATE_CHANGED: \n");
            break;
        }
        case GST_MESSAGE_SEGMENT_DONE: {
            g_print ("Bus msg: GST_MESSAGE_SEGMENT_DONE\n");

            break;
        }
        default:
        {
            g_print ("Msg-Type: %d", GST_MESSAGE_TYPE (msg));
            break;
        }    
        break;
    }

    return TRUE;
}

static void
comp_new_pad (GstElement *element,
              GstPad     *pad,
              gpointer    data)
{
    GstPad *sinkpad;
    /* We can now link this pad with the  decoder */

//    sinkpad = gst_element_get_pad (parser, "sink"); // do we have to 
ask for a compatible pad?
    sinkpad = gst_element_get_compatible_pad (conv, pad, 
gst_pad_get_caps(pad));

    gchar* srcCapsStr = gst_caps_to_string (gst_pad_get_caps(pad) );
    gchar* sinkCapsStr = gst_caps_to_string (gst_pad_get_caps(sinkpad) );
    //  
    GstPadLinkReturn result = gst_pad_link (pad, sinkpad);
    if (result == GST_PAD_LINK_OK)
        g_print ("Dynamic pad created, linking comp/parser\n");
    else
        g_print ("comp_new_pad(): gst_pad_link() failed! result: %d\n", 
result);
 

    gst_object_unref (sinkpad);
}

int
main (int   argc,
      char *argv[])
{
    GMainLoop *loop;
    GstBus *bus;

    /* initialize GStreamer */
    gst_init (&argc, &argv);
    loop = g_main_loop_new (NULL, FALSE);
    gst_debug_set_active(true);
    gst_debug_set_threshold_for_name ("*", GST_LEVEL_INFO ); // 
GST_LEVEL_LOG

    /* check input arguments */
    if (argc != 3) {
        g_print ("Usage: %s <filename1> <filename2>\n", argv[0]);
        return -1;
    }

    /* create elements */
    pipeline = gst_pipeline_new ("TM_video-player");
    conv = gst_element_factory_make ("ffmpegcolorspace", 
"ffmpeg-colorspace");
    sink = gst_element_factory_make ("directdrawsink", 
"directdrawsink-output");
    comp = gst_element_factory_make("gnlcomposition", "mycomposition");
    gnlfilesource1 = gst_element_factory_make("gnlfilesource", "video1");
    gnlfilesource2 = gst_element_factory_make("gnlfilesource", "video2");
    gst_bin_add (GST_BIN (comp), gnlfilesource1);
    gst_bin_add (GST_BIN (comp), gnlfilesource2);

    g_object_set (G_OBJECT (gnlfilesource1), "location", argv[1], 
"start", 0 * GST_SECOND, "duration", 5 * GST_SECOND, "media-start", 10 * 
GST_SECOND, "media-duration", 5 * GST_SECOND, NULL);
    g_object_set (G_OBJECT (gnlfilesource2), "location", argv[2], 
"start", 8 * GST_SECOND, "duration", 5 * GST_SECOND, "media-start", 10 * 
GST_SECOND, "media-duration", 5 * GST_SECOND, NULL);

    if (!pipeline || !conv || !sink || !comp) {
        g_print ("One element could not be created\n");
        return -1;
    }

    bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline));
    gst_bus_add_watch (bus, bus_call, loop);
    gst_object_unref (bus);

    /* put all elements in a bin */
    gst_bin_add_many (GST_BIN (pipeline), comp, conv, sink,  NULL);

    gst_element_link (conv, sink);

    g_signal_connect (comp, "pad-added", G_CALLBACK (comp_new_pad), NULL);

    /* Now set to playing and iterate. */
    g_print ("Setting to PLAYING\n");
    gst_element_set_state (pipeline, GST_STATE_PLAYING);
    g_print ("Running\n");

    g_main_loop_run (loop);

    /* clean up nicely */
    g_print ("Returned, stopping playback\n");
    gst_element_set_state (pipeline, GST_STATE_NULL);
    g_print ("Deleting pipeline\n");
    gst_object_unref (GST_OBJECT (pipeline));

    return 0;
}