windows使用libvlc進行網路串流遇到的一些問題及解決方案

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先貼代碼，

#define WIFI_W 640
#define WIFI_H 480

struct ctx{    uchar* frame;};class CConnectWIFI{public:    CConnectWIFI(void);    void Init(HWND hWnd);        libvlc_instance_t*        m_vlcInst;    libvlc_media_player_t*    m_vlcMplay;    libvlc_media_t*            m_vlcMedia;    struct ctx context;        ~CConnectWIFI(void);};CConnectWIFI::CConnectWIFI(void){    m_vlcInst = NULL;    m_vlcMplay = NULL;    m_vlcMedia = NULL;            context.frame = new uchar[WIFI_W * WIFI_H * 3];    memset(context.frame, 0, WIFI_W*WIFI_H*3);    m_vlcInst = libvlc_new(0, NULL);    }CConnectWIFI::~CConnectWIFI(void){    if(m_vlcMplay)    {        libvlc_media_player_release(m_vlcMplay);        m_vlcMplay = NULL;    }    if(m_vlcInst)    {        libvlc_release(m_vlcInst);        m_vlcInst = NULL;    }    if (context.frame)    {        delete []context.frame;        context.frame = NULL;    }}void* lock(void* data, void** p_pixels){    struct ctx* ctx = (struct ctx*)data;    *p_pixels = ctx->frame;    return NULL;}void unlock(void* data, void* id, void* const* p_pixels){    uchar* pixels = (uchar*)*p_pixels;            ImageProcessCallBack(pixels, WIFI_W, WIFI_H);}void display(void *data, void *id){    //(void) data;    //ASSERT(id == NULL);}void CConnectWIFI::Init(HWND hWnd){    m_vlcMedia = libvlc_media_new_location(m_vlcInst, "http://10.10.1.1:8196");    libvlc_media_add_option(m_vlcMedia, ":network-caching=10");    m_vlcMplay = libvlc_media_player_new_from_media(m_vlcMedia);        libvlc_media_player_set_hwnd(m_vlcMplay, hWnd);    libvlc_media_release(m_vlcMedia);            libvlc_video_set_callbacks(m_vlcMplay, lock, unlock, display, &context);    libvlc_video_set_format(m_vlcMplay, "RV24", WIFI_W, WIFI_H, WIFI_W * 3);    int res = libvlc_media_player_play(m_vlcMplay);}

以上代碼是訪問wifi映像裝置的一段代碼，也是第一次接觸vlc，很多地方不是很清楚。

其中libvlc_media_add_option(m_vlcMedia, ":network-caching=10");是為瞭解決緩衝時間過長導致延遲的問題，如果太大了則延遲嚴重，太小了則很卡，根據情況設定。另外還有個問題不理解，串連正常之後，突然中斷網路，竟然還能調用回呼函數ImageProcessCallBack，且一隻調用，只不過都是同一幀資料。難道是所謂的“拉”（pull）模式？這個問題怎麼解決，有做過的麻煩請在下方留言，感謝！