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我编写了一个演示程序来执行 seek 。这是代码

#define BOOST_ALL_NO_LIB
#include <iostream>

#include <gst/gst.h>
#include <glib/gmain.h>
#include <boost/thread.hpp>
using namespace std;
int bus_state_changed(GstBus *bus, GstMessage *msg, gpointer loop)
{
    std::cerr << "bus message: " << GST_MESSAGE_TYPE_NAME(msg) << std::endl;
        GMainLoop *ptrLoop = (GMainLoop *) loop;
    switch (GST_MESSAGE_TYPE(msg))
    {
    case GST_MESSAGE_EOS:
        std::cout<<"End of stream\n";
        g_main_loop_quit(ptrLoop);
        break;
    case GST_MESSAGE_ERROR:
        {
        GError *err=0;

        gst_message_parse_error(msg, &err, 0);
        std::cerr<< "GST_MESSAGE_ERROR: " << err->message << ": "
        << GST_MESSAGE_SRC_NAME(msg);
        g_error_free(err);
        g_main_loop_quit(ptrLoop);
        break;
        }

    case GST_MESSAGE_STATE_CHANGED: {
        GstState old_state, new_state;

        gst_message_parse_state_changed (msg, &old_state, &new_state, NULL);
        g_print ("Element %s changed state from %s to %s.\n",
            GST_OBJECT_NAME (msg->src),
            gst_element_state_get_name (old_state),
            gst_element_state_get_name (new_state));
        break;
                                    }

    default:
        break;
    }
    return true;
}

int main()
{
    GMainLoop *loop;
    GstElement *pipeline=0;
    GstBus *bus=0;
    guint busWatchId;

    GError *err = 0;
    if(!gst_init_check(0, 0,&err))
    {
        std::string errmsg(err->message);
        g_error_free(err);
    }

    loop = g_main_loop_new(NULL, FALSE);

    //create a pipeline for audio/video playback
    pipeline = gst_element_factory_make("playbin2", "player");

    if(!pipeline)
    {
        std::cout<<"Can not get pipeline";
    }

    //get a bus to receive GSTMessages from pipeline.
    bus = gst_pipeline_get_bus(GST_PIPELINE(pipeline));

    if(!bus)
    {
        std::cout<<"Can not get bus";
    }

    //when the state of bus changes call bus_state_changed function.
    busWatchId = gst_bus_add_watch(bus, bus_state_changed, loop);
    //make the pipeline ready to use.
    gst_element_set_state(pipeline, GST_STATE_READY);

    boost::thread gloopThread([&](){g_main_loop_run(loop);});

g_object_set(G_OBJECT(pipeline), "uri","file:///C:/song.mp3" , 0);
gst_element_set_state(pipeline, GST_STATE_PLAYING);


std::cout<<"Seek will be perfomed now "<<std::endl;
gint64 pos =-1;
GstFormat fmt = GST_FORMAT_TIME;
    while(true)
    {

    if (!gst_element_query_position(pipeline, &fmt, &pos))
{
    std::cerr << "gst_element_query_position failed" << std::endl;
}
    //std::cout<<"\nCurrent Position"<<pos<<std::endl;
    if(pos > 2807641720)  // 3 seconds
    {
    if (!gst_element_seek_simple(pipeline, GST_FORMAT_TIME, GST_SEEK_FLAG_FLUSH,44531201814 ))
{
    std::cerr << "gst_element_seek failed" << std::endl;
}

    GstStateChangeReturn r = gst_element_get_state(pipeline, 0, 0, -1);
    std::cout << "state change return = " << r << std::endl;

        if (!gst_element_query_position(pipeline, &fmt, &pos))
{
    std::cerr << "gst_element_query_position failed 2" << std::endl;
}
    //std::cout<<"\nCurrent Position :"<<pos<<std::endl;
    break;
    }
   }
    while(true)
    {

        gst_element_query_position(pipeline, &fmt, &pos);
    //std::cout<<"\nCurrent Position"<<pos<<std::endl;
    if(pos > 47531201814)  // 3 seconds
    {
    gst_element_seek_simple(pipeline, GST_FORMAT_TIME, GST_SEEK_FLAG_FLUSH,50531201814 );
        gst_element_query_position(pipeline, &fmt, &pos);
    //std::cout<<"\nCurrent Position :"<<pos<<std::endl;
    break;
    }
   }
    while(true);


    return 0;
}

这是我的 .pro 文件

TEMPLATE = app
CONFIG += console
CONFIG -= qt

SOURCES += main.cpp
QMAKE_CXXFLAGS += -std=c++0x

CONFIG += link_pkgconfig
PKGCONFIG += gstreamer-0.10


win32: INCLUDEPATH += c:\boost_1_48_0 \

win32:CONFIG(release, debug|release): LIBS += -L$$PWD/../../../boost_1_48_0/stage/lib/ -lboost_thread-vc100-mt-1_48
else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/../../../boost_1_48_0/stage/lib/ -lboost_thread-vc100-mt-gd-1_48

INCLUDEPATH += $$PWD/../../../boost_1_48_0/stage
DEPENDPATH += $$PWD/../../../boost_1_48_0/stage

运行代码时，歌曲播放良好，但触发搜索时存在搜索间隙。相同的代码在 linux 上完美运行。我无法理解问题出在哪里。谢谢

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