layer1pin.cpp

mysee网络直播源代码Mysee Lite是Mysee独立研发的网络视频流媒体播放系统。在应有了P2P技术和一系列先进流媒体技术之后

/*
 *  Openmysee
 *
 *  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 "stdafx.h"
#include ".\layer1pin.h"

Layer1Pin::Layer1Pin(NPLayer1::Layer1* pLayer1, bool bAudio) : 
m_pLayer1(pLayer1), 
m_bAudio(bAudio),
m_needmediatype(true)
{
    if(bAudio)
        m_maxSize = 200*1024;   //音频数据缓冲区按200K计算
    else
        m_maxSize = 1000*1024;   //视频缓冲按1000K计算
}

Layer1Pin::~Layer1Pin(void)
{
}

void Layer1Pin::Start()
{
    m_needmediatype = true;

}

P2P_RETURN_TYPE Layer1Pin::GetDataEx(
		SampleHeader& header,	// out, 数据头
		PBYTE& pData,			// out, 存储数据的缓冲区
		const UINT maxSize,		// in, 缓冲区的长度
		const bool bKeySample,	// in, 是否寻找关键帧
        bool  bSaveSample       //in, 是否缓冲当前的sample到本地
		)
{

    P2P_RETURN_TYPE ret =  m_pLayer1->GetData(header, pData, maxSize, m_bAudio, bKeySample);
    if(ret != PRT_OK)
        return ret;

    if(header.start == 0 && header.length == 0) //这是媒体类型的头
    {
        m_mediatype.SaveMediaTypeData(header, pData, 256); //保存媒体类型数据，存开头的256个byte也应该够了
    }
    else if(bSaveSample)
    {
        SampleBuffer::Clean();  //先清理当前的缓冲数据
        SampleBuffer::SaveData(header, pData, maxSize); //保存被缓冲的sample
    }

    return ret;
}

P2P_RETURN_TYPE Layer1Pin::PeerData(
		SampleHeader& header,	// out, 数据头
		PBYTE& pData,			// out, 存储数据的缓冲区
		const UINT maxSize,		// in, 缓冲区的长度
		const bool bKeySample	// in, 是否寻找关键帧
		)
{
    if(IsAnyDataSaved())    //如果已经缓冲了数据，只显示缓冲的那块数据
    {
        SampleBuffer::PeerData(header, pData, maxSize);
        return PRT_OK;
    }

    return GetDataEx(header, pData, maxSize, bKeySample, true);
}

P2P_RETURN_TYPE Layer1Pin::GetData(
		SampleHeader& header,	// out, 数据头
		PBYTE& pData,			// out, 存储数据的缓冲区
		const UINT maxSize,		// in, 缓冲区的长度
		const bool bKeySample	// in, 是否寻找关键帧
		)
{
    if(m_needmediatype)
    {
        int m_errcount = 0;
        while(!m_mediatype.IsInited())
        {
            if(m_errcount > 3)
            {
                //我ft! 类型数据不知道到哪里去了。只有放弃了
                MessageBox(NULL, "获取媒体类型失败了。播放将会停止", "", MB_OK);
                return PRT_SYS;
            }

            P2P_RETURN_TYPE ret = GetDataEx(header, pData, maxSize, bKeySample, true);
            if(ret != PRT_OK)       //得不到数据头，再试几次
            {
                m_errcount++;
                Sleep(50);
            }
            else
                break;
        }

       //得到了数据头，可能是刚刚peerdata得到的,也可能是之前存下来的,恢复它
       m_mediatype.RestoreMediaTypeData(header, pData, maxSize);
            
       m_needmediatype = false;
       return PRT_OK; 
    }

    if(IsAnyDataSaved() && SampleBuffer::GetData(header, pData, maxSize))  //有被缓冲的数据, 将缓冲的数据恢复
    {
        if(!(bKeySample && !header.bSyncPoint))    //要求关键帧，但我们缓冲的不是，就只能放弃，从layer1中获得，否则，可以返回
            return PRT_OK;
    }

    return GetDataEx(header, pData, maxSize, bKeySample, false);
}