EasyDarwin开源流媒体云平台之云台ptz控制设计与实现

本文转自EasyDarwin开源团队成员Alex的博客：http://blog.csdn.net/cai6811376/article/details/51912692

近日，EasyDarwin云平台加入云台控制功能，完善了云平台的功能，提升了用户体验。具体设计以及实现如下。

流程设计

客户端通过RESTful接口向云平台发送控制命令；

云平台组织控制报文向设备发送；

设备执行后向云平台返回控制响应报文；

云平台接收响应报文后将控制结果返回给客户端。

接口设计

首先我们设计云台控制的接口，接口为RESTful方式接口。

http://[ip]:[port]/api/ptzcontrol?device=001001000058&channel=0&actiontype=single&c
ommand=down&speed=5&protocol=onvif

device：设备序列号；
channel：通道；
protocol：控制模式，包括 Onvif、 SDK；
actiontype： ptz 控制模式，分为连续（ Continuous）、单步（ Single）；
command： ptz 控制命令包括转动、变焦等，
stop/up/down/left/right/zoomin/zoomout/focusin/focusout/aperturein/apertureout；
speed： ptz 控制速度。

通讯报文设计

//云平台响应客户端控制
{
   "EasyDarwin" : {
      "Body" : {
         "Channel" : "0",
         "Protocol" : "ONVIF",
         "Reserve" : "1",
         "Serial" : "001001000058"
      },
      "Header" : {
         "CSeq" : "2",
         "ErrorNum" : "200",
         "ErrorString" : "Success OK",
         "MessageType" : "MSG_SC_PTZ_CONTROL_ACK",
         "Version" : "1.0"
      }
   }
}

//云平台向设备发送控制报文
{
   "EasyDarwin" : {
      "Body" : {
         "ActionType" : "SINGLE",
         "Channel" : "0",
         "Command" : "DOWN",
         "From" : "f6a221eec46b47dea8ae1a2bd11f8d02",
         "Protocol" : "ONVIF",
         "Reserve" : "1",
         "Serial" : "001001000058",
         "Speed" : "5",
         "To" : "245d6ec33cd247b7b7524219552db4d8",
         "Via" : "27823d2e8b6b4032b453d435a16b7be8"
      },
      "Header" : {
         "CSeq" : "1",
         "MessageType" : "MSG_SD_CONTROL_PTZ_REQ",
         "Version" : "1.0"
      }
   }
}

//设备响应云平台控制
{
   "EasyDarwin" : {
      "Body" : {
         "Channel" : "0",
         "From" : "245d6ec33cd247b7b7524219552db4d8",
         "Protocol" : "ONVIF",
         "Reserve" : "1",
         "Serial" : "001001000058",
         "To" : "f6a221eec46b47dea8ae1a2bd11f8d02",
         "Via" : "27823d2e8b6b4032b453d435a16b7be8"
      },
      "Header" : {
         "CSeq" : "1",
         "ErrorNum" : "200",
         "ErrorString" : "Success OK",
         "MessageType" : "MSG_DS_CONTROL_PTZ_ACK",
         "Version" : "1.0"
      }
   }
}

格式说明：
Serial：设备序列号；
Channel：摄像机通道号；
Protocol：指定 ptz 控制方式， ONVIF 协议或者设备 SDK；
ActionType： ptz 控制类型，包括连续或者单步；
Command： ptz 控制命令，包括停止，上下左右旋转，变焦等等；
Speed： ptz 控制速度；
From: EasyCMS 接收 Client 访问的 SessionID；
To: EasyCMS 向 Device 发送报文的 SessionID；
Via: EasyCMS 的 ServiceID；

实现

//EasyCMS HTTPSession.cpp
//在session map中查找device session，组织控制报文，通过device session发送给设备
OSRefTableEx* deviceMap = QTSServerInterface::GetServer()->GetDeviceSessionMap();
    OSRefTableEx::OSRefEx* theDevRef = deviceMap->Resolve(chSerial);
    if (theDevRef == NULL)
        return EASY_ERROR_DEVICE_NOT_FOUND;

    OSRefReleaserEx releaser(deviceMap, chSerial);

    HTTPSession* pDevSession = static_cast<HTTPSession *>(theDevRef->GetObjectPtr());

    EasyProtocolACK reqreq(MSG_SD_CONTROL_PTZ_REQ);
    EasyJsonValue headerheader, bodybody;

    char chTemp[16] = { 0 };
    UInt32 uDevCseq = pDevSession->GetCSeq();
    sprintf(chTemp, "%d", uDevCseq);
    headerheader[EASY_TAG_CSEQ] = string(chTemp);
    headerheader[EASY_TAG_VERSION] = EASY_PROTOCOL_VERSION;

    string strProtocol(chProtocol);
    string strActionType(chActionType);
    string strCmd(chCmd);
    boost::to_upper(strProtocol);
    boost::to_upper(strActionType);
    boost::to_upper(strCmd);

    bodybody[EASY_TAG_SERIAL] = chSerial;
    bodybody[EASY_TAG_CHANNEL] = chChannel;
    bodybody[EASY_TAG_PROTOCOL] = strProtocol;
    bodybody[EASY_TAG_RESERVE] = chReserve;
    bodybody[EASY_TAG_ACTION_TYPE] = strActionType;
    bodybody[EASY_TAG_CMD] = strCmd;
    bodybody[EASY_TAG_SPEED] = chSpeed;
    bodybody[EASY_TAG_FROM] = fSessionID;
    bodybody[EASY_TAG_TO] = pDevSession->GetValue(EasyHTTPSessionID)->GetAsCString();
    bodybody[EASY_TAG_VIA] = QTSServerInterface::GetServer()->GetCloudServiceNodeID();

    reqreq.SetHead(headerheader);
    reqreq.SetBody(bodybody);

    string buffer = reqreq.GetMsg();
    StrPtrLen theValue(const_cast<char*>(buffer.c_str()), buffer.size());
    pDevSession->SendHTTPPacket(&theValue, false, false);

//EasyCamera EasyCMSSession.cpp processControlPTZReq
//EasyCamera接收控制报文，调用EasyCameraSource的控制接口

QTSS_Error EasyCMSSession::processControlPTZReq() const
{
    EasyMsgSDControlPTZREQ ctrlPTZReq(fContentBuffer);

    string serial = ctrlPTZReq.GetBodyValue(EASY_TAG_SERIAL);
    string protocol = ctrlPTZReq.GetBodyValue(EASY_TAG_PROTOCOL);
    string channel = ctrlPTZReq.GetBodyValue(EASY_TAG_CHANNEL);
    string reserve = ctrlPTZReq.GetBodyValue(EASY_TAG_RESERVE);
    string actionType = ctrlPTZReq.GetBodyValue(EASY_TAG_ACTION_TYPE);
    string command = ctrlPTZReq.GetBodyValue(EASY_TAG_CMD);
    string speed = ctrlPTZReq.GetBodyValue(EASY_TAG_SPEED);
    string from = ctrlPTZReq.GetBodyValue(EASY_TAG_FROM);
    string to = ctrlPTZReq.GetBodyValue(EASY_TAG_TO);
    string via = ctrlPTZReq.GetBodyValue(EASY_TAG_VIA);

    if (serial.empty() || channel.empty() || command.empty())
    {
        return QTSS_ValueNotFound;
    }

    QTSS_RoleParams params;
    params.cameraPTZParams.inActionType = EasyProtocol::GetPTZActionType(actionType);
    params.cameraPTZParams.inCommand = EasyProtocol::GetPTZCMDType(command);
    params.cameraPTZParams.inSpeed = EasyUtil::String2Int(speed);

    QTSS_Error errCode = QTSS_NoErr;
    UInt32 fCurrentModule = 0;
    UInt32 numModules = QTSServerInterface::GetNumModulesInRole(QTSSModule::kControlPTZRole);
    for (; fCurrentModule < numModules; ++fCurrentModule)
    {
        QTSSModule* theModule = QTSServerInterface::GetModule(QTSSModule::kControlPTZRole, fCurrentModule);
        errCode = theModule->CallDispatch(Easy_ControlPTZ_Role, &params);
    }

    EasyJsonValue body;
    body[EASY_TAG_SERIAL] = serial;
    body[EASY_TAG_CHANNEL] = channel;
    body[EASY_TAG_RESERVE] = reserve;
    body[EASY_TAG_PROTOCOL] = protocol;
    body[EASY_TAG_FROM] = to;
    body[EASY_TAG_TO] = from;
    body[EASY_TAG_VIA] = via;

    EasyMsgDSControlPTZACK rsp(body, ctrlPTZReq.GetMsgCSeq(), getStatusNo(errCode));

    string msg = rsp.GetMsg();
    StrPtrLen jsonContent(const_cast<char*>(msg.data()));
    HTTPRequest httpAck(&QTSServerInterface::GetServerHeader(), httpResponseType);

    if (httpAck.CreateResponseHeader())
    {
        if (jsonContent.Len)
            httpAck.AppendContentLengthHeader(jsonContent.Len);

        //Push msg to OutputBuffer
        char respHeader[2048] = { 0 };
        StrPtrLen* ackPtr = httpAck.GetCompleteHTTPHeader();
        strncpy(respHeader, ackPtr->Ptr, ackPtr->Len);

        fOutputStream->Put(respHeader);
        if (jsonContent.Len > 0)
            fOutputStream->Put(jsonContent.Ptr, jsonContent.Len);
    }

    return errCode;
}

//EasyCamera EasyCameraSource.cpp ControlPTZ
QTSS_Error EasyCameraSource::ControlPTZ(Easy_CameraPTZ_Params* params)
{
    QTSS_Error result = QTSS_RequestFailed;

    if (cameraLogin())
    {
        HI_S32 error;
        if (params->inActionType == EASY_PTZ_ACTION_TYPE_CONTINUOUS)
        {
            error = HI_NET_DEV_PTZ_Ctrl_Standard(m_u32Handle, getPTZCMDFromCMDType(params->inCommand), params->inSpeed);
        }
        else if (params->inActionType == EASY_PTZ_ACTION_TYPE_SINGLE)
        {
            error = HI_NET_DEV_PTZ_Ctrl_StandardEx(m_u32Handle, getPTZCMDFromCMDType(params->inCommand));
        }
        else
        {
            return QTSS_BadArgument;
        }

        if (error == HI_SUCCESS)
        {
            result = QTSS_NoErr;
        }
        else
        {
            result = QTSS_RequestFailed;
        }
    }

    return result;
}