#include
static gboolean bus_call(GstBus * bus, GstMessage * msg, gpointer data)//定义消息处理函数
{ 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;
}
int main(int argc, char *argv[])
{GMainLoop *loop;
GstElement *pipeline, *filesrc, *decoder, *audiosink; //定义组件
GstBus *bus;
gst_init(&argc, &argv);
loop = g_main_loop_new(NULL, FALSE); //创建主循环，在执行 g_main_loop_run后正式开始循环
if (argc != 2) {
g_printerr("Usage:%s
return -1;
}
//创建管道和组件
pipeline = gst_pipeline_new("pipeline");
filesrc = gst_element_factory_make("filesrc", "disk_source");
decoder = gst_element_factory_make("mad", "decoder");
audiosink=gst_element_factory_make("autoaudiosink","play_audio");
if (!pipeline || !filesrc || !decoder || !audiosink) {
g_printerr("One element could not be created.Exiting.\n");
return -1;
}
//设置source的location参数,即文件地址
g_object_set(G_OBJECT(filesrc), "location", argv[1], NULL);
g_print("argv[1]:%s\n",argv[1]);
//得到管道的消息总线
bus = gst_pipeline_get_bus(GST_PIPELINE(pipeline));
// g_print("pipeline bus:%s\n",bus);
//添加消息监视器
gst_bus_add_watch(bus, bus_call, loop);
gst_object_unref(bus);
//把组件添加到管道中.管道是一个特殊的组件，可以更好的让数据流动
gst_bin_add_many(GST_BIn(pipeline), filesrc,decoder,audiosink, NULL);
//依次连接组件
gst_element_link_many(filesrc, decoder, audiosink, NULL);
//开始播放
//gst_element_set_state(pipeline, GST_STATE_READY);
gst_element_set_state(pipeline, GST_STATE_PLAYING);
g_print("Running\n");
//开始循环
g_main_loop_run(loop);
g_print("Returned,stopping playback\n");
gst_element_set_state(pipeline, GST_STATE_NULL);
gst_object_unref(GST_OBJECT(pipeline));
return 0;
}