gst-backend.c

/*
 * Copyright (C) 2008 Felipe Contreras.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <gst/gst.h>
#if GST_VERSION_MAJOR == 0
  #include <gst/interfaces/xoverlay.h>
  //compat defines
  #define gst_is_video_overlay_prepare_window_handle_message  gst_x_overlay_set_window_handle
  #define gst_video_overlay_set_window_handle gst_x_overlay_set_window_handle
  #define GstVideoOverlay GstXOverlay
  #define GST_VIDEO_OVERLAY GST_X_OVERLAY
#else
  #include <gst/video/videooverlay.h>
#endif

#include "gst-backend.h"

static GstElement *pipeline;
static GstElement *videosink;
static GstElement *audiosink;
static gpointer window;
static GstSeekFlags seek_flags = GST_SEEK_FLAG_FLUSH | GST_SEEK_FLAG_KEY_UNIT;

static gboolean
bus_cb (GstBus *bus,
        GstMessage *msg,
        gpointer data)
{
    switch (GST_MESSAGE_TYPE (msg))
    {
        case GST_MESSAGE_EOS:
            {
                g_debug ("end-of-stream");
                break;
            }
        case GST_MESSAGE_ERROR:
            {
                gchar *debug;
                GError *err;

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

                g_warning ("Error: %s", err->message);
                g_error_free (err);
                break;
            }
        default:
            break;
    }

    return TRUE;
}

void
backend_init (int *argc,
              char **argv[])
{
    gst_init (argc, argv);
}

void
backend_set_window (gpointer window_)
{
    window = window_;
}

static GstBusSyncReply
bus_sync_handler (GstBus * bus, GstMessage * message, gpointer user_data)
{
 #if GST_VERSION_MAJOR == 0
 if (!gst_structure_has_name (message->structure, "prepare-xwindow-id"))
   return GST_BUS_PASS;
 #else
 // ignore anything but 'prepare-window-handle' element messages
 if (!gst_is_video_overlay_prepare_window_handle_message (message))
   return GST_BUS_PASS;
 #endif

 if (window != 0) {
   GstVideoOverlay *overlay;

   // GST_MESSAGE_SRC (message) will be the video sink element
   overlay = GST_VIDEO_OVERLAY (GST_MESSAGE_SRC (message));
   gst_video_overlay_set_window_handle (overlay, window);
 } else {
   g_warning ("Should have obtained video_window_handle by now!");
 }

 gst_message_unref (message);
 return GST_BUS_DROP;
}

void
backend_play (const gchar *filename, const gchar *vsink,
              const gchar *asink, int keep_aspect)
{
	if (!vsink) vsink = "autovideosink";
	if (!asink) asink = "autoaudiosink";
    backend_stop ();

    pipeline = gst_element_factory_make ("playbin", "gst-player");
    //gst_video_overlay_set_window_handle (pipeline, window);
    {
        GstBus *bus;
        bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline));
        #if GST_VERSION_MAJOR == 0
        gst_bus_set_sync_handler (bus, (GstBusSyncHandler) bus_sync_handler, NULL);
        #else
		gst_bus_set_sync_handler (bus, (GstBusSyncHandler) bus_sync_handler, NULL, NULL);
		#endif
        gst_bus_add_watch (bus, bus_cb, NULL);
        gst_object_unref (bus);
    }

    //videosink = gst_element_factory_make (vsink, "videosink");
    //audiosink = gst_element_factory_make (asink, "videosink");
    videosink = gst_parse_bin_from_description (vsink, TRUE, NULL);
    audiosink = gst_parse_bin_from_description (asink, TRUE, NULL);

    g_object_set (G_OBJECT (pipeline), "video-sink", videosink, NULL);
    g_object_set (G_OBJECT (pipeline), "audio-sink", audiosink, NULL);

    if (keep_aspect)
		g_object_set (G_OBJECT (videosink), "force-aspect-ratio", TRUE, NULL);

    {
        gchar *uri;

        if (gst_uri_is_valid (filename))
        {
            uri = g_strdup (filename);
        }
        else if (g_path_is_absolute (filename))
        {
            uri = g_filename_to_uri (filename, NULL, NULL);
        }
        else
        {
            gchar *tmp;
            tmp = g_build_filename (g_get_current_dir (), filename, NULL);
            uri = g_filename_to_uri (tmp, NULL, NULL);
            g_free (tmp);
        }

        g_debug ("%s", uri);
        g_object_set (G_OBJECT (pipeline), "uri", uri, NULL);
        g_free (uri);
    }

    gst_element_set_state (pipeline, GST_STATE_PLAYING);
}

void
backend_stop (void)
{
    if (pipeline)
    {
        gst_element_set_state (pipeline, GST_STATE_NULL);
        gst_object_unref (GST_OBJECT (pipeline));
        pipeline = NULL;
    }
}

void
backend_pause (void)
{
    gst_element_set_state (pipeline, GST_STATE_PAUSED);
}

void
backend_resume (void)
{
    gst_element_set_state (pipeline, GST_STATE_PLAYING);
}

void
backend_reset (void)
{
    gst_element_seek (pipeline, 1.0,
                      GST_FORMAT_TIME,
                      seek_flags,
                      GST_SEEK_TYPE_SET, 0,
                      GST_SEEK_TYPE_NONE, GST_CLOCK_TIME_NONE);
}

void
backend_seek (gint value)
{
    gst_element_seek (pipeline, 1.0,
                      GST_FORMAT_TIME,
                      seek_flags,
                      GST_SEEK_TYPE_END, value * GST_SECOND,
                      GST_SEEK_TYPE_NONE, GST_CLOCK_TIME_NONE);
}

void
backend_seek_absolute (guint64 value)
{
    gst_element_seek (pipeline, 1.0,
                      GST_FORMAT_TIME,
                      seek_flags,
                      GST_SEEK_TYPE_SET, value,
                      GST_SEEK_TYPE_NONE, GST_CLOCK_TIME_NONE);
}

guint64
backend_query_position (void)
{
    GstFormat format = GST_FORMAT_TIME;
    gint64 cur;
    gboolean result;

	#if GST_VERSION_MAJOR == 0
    result = gst_element_query_position (pipeline, &format, &cur);
    #else
    result = gst_element_query_position (pipeline, format, &cur);
    #endif
    if (!result || format != GST_FORMAT_TIME)
        return GST_CLOCK_TIME_NONE;

    return cur;
}

guint64
backend_query_duration (void)
{
    GstFormat format = GST_FORMAT_TIME;
    gint64 cur;
    gboolean result;

	#if GST_VERSION_MAJOR == 0
	result = gst_element_query_duration (pipeline, &format, &cur);
	#else
    result = gst_element_query_duration (pipeline, format, &cur);
    #endif
    if (!result || format != GST_FORMAT_TIME)
        return GST_CLOCK_TIME_NONE;

    return cur;
}

void
backend_deinit (void)
{
}