海康工业相机SDK+OpenCV实例(2)：

RawDataFormatConvert详解

文章目录

海康工业相机SDK+OpenCV实例(2)：
RawDataFormatConvert详解
前言
一、海康工业相机SDK详解
二、OpenCV相关操作
三、运行结果

前言

在前文讲解了海康工业相机SDK与OpenCV的安装与环境配置，本文接着讲解SDK给的OpenCV的demo，主要实现RawDataFormatConvert的功能，即将海康连续采集的图像转化为OpenCV的Mat格式并显示于屏幕。

一、海康工业相机SDK详解

在海康SDK安装位置，找到D:\Softwares\MVS\Development\Samples\OpenCV\VC的Samples_OpenCV.sln并打开，下面会先对SDK的调用相机的各功能进行详解：

1.1 首先定义句柄和相机操作的返回值，当相机操作出现问题时，需要将nRet，可以根据对应的返回值查询可能出现的问题。

    int nRet = MV_OK;void* handle = NULL;

1.2 列出当前的设备管理目录，输入对应值，选择相应的相机设备。

        // Enum deviceMV_CC_DEVICE_INFO_LIST stDeviceList;memset(&stDeviceList, 0, sizeof(MV_CC_DEVICE_INFO_LIST));nRet = MV_CC_EnumDevices(MV_GIGE_DEVICE | MV_USB_DEVICE, &stDeviceList);if (MV_OK != nRet){printf("Enum Devices fail! nRet [0x%x]\n", nRet);break;}if (stDeviceList.nDeviceNum > 0){for (unsigned int i = 0; i < stDeviceList.nDeviceNum; i++){printf("[device %d]:\n", i);MV_CC_DEVICE_INFO* pDeviceInfo = stDeviceList.pDeviceInfo[i];if (NULL == pDeviceInfo){break;}PrintDeviceInfo(pDeviceInfo);}}else{printf("Find No Devices!\n");break;}// input the format to convertunsigned int nFormat = 0;// select device to connectprintf("Please Input camera index(0-%d):", stDeviceList.nDeviceNum-1);unsigned int nIndex = 0;scanf("%d", &nIndex);if (nIndex >= stDeviceList.nDeviceNum){printf("Input error!\n");break;}

1.3 创建句柄并打开相机设备

        // Select device and create handlenRet = MV_CC_CreateHandle(&handle, stDeviceList.pDeviceInfo[nIndex]);if (MV_OK != nRet){printf("Create Handle fail! nRet [0x%x]\n", nRet);break;}// open devicenRet = MV_CC_OpenDevice(handle);if (MV_OK != nRet){printf("Open Device fail! nRet [0x%x]\n", nRet);break;}

1.4 设置相机参数，图片的宽度与高度、相机的曝光时间与增益；返回相机参数，图片的宽度与高度、相机的曝光时间与增益。

        nRet = SetParameters(handle, WidthValue, HeightValue, ExposureTimeValue, GainValue);if (MV_OK != nRet){printf("Set parameters fail! nRet [0x%x]\n", nRet);break;}nRet = GetParameters(handle);if (MV_OK != nRet){printf("Get parameters fail! nRet [0x%x]\n", nRet);break;}

1.5 设置网络最佳的包大小，设置相机的触发模式

        // Detection network optimal package size(It only works for the GigE camera)if (stDeviceList.pDeviceInfo[nIndex]->nTLayerType == MV_GIGE_DEVICE){int nPacketSize = MV_CC_GetOptimalPacketSize(handle);if (nPacketSize > 0){nRet = MV_CC_SetIntValue(handle,"GevSCPSPacketSize",nPacketSize);if(nRet != MV_OK){printf("Warning: Set Packet Size fail nRet [0x%x]!", nRet);}}else{printf("Warning: Get Packet Size fail nRet [0x%x]!", nPacketSize);}}// Set trigger mode as offnRet = MV_CC_SetEnumValue(handle, "TriggerMode", 0);if (MV_OK != nRet){printf("Set Trigger Mode fail! nRet [0x%x]\n", nRet);break;}// Get payload sizeMVCC_INTVALUE stParam;memset(&stParam, 0, sizeof(MVCC_INTVALUE));nRet = MV_CC_GetIntValue(handle, "PayloadSize", &stParam);if (MV_OK != nRet){printf("Get PayloadSize fail! nRet [0x%x]\n", nRet);break;}g_nPayloadSize = stParam.nCurValue;

1.6 开启连续采集模式，并分配缓冲内存区

        // Start grab imagenRet = MV_CC_StartGrabbing(handle);if (MV_OK != nRet){printf("Start Grabbing fail! nRet [0x%x]\n", nRet);break;}MV_FRAME_OUT stImageInfo = {0};memset(&stImageInfo, 0, sizeof(MV_FRAME_OUT));unsigned char * pData = (unsigned char *)malloc(sizeof(unsigned char) * (g_nPayloadSize));if (pData == NULL){printf("Allocate memory failed.\n");break;}

1.7 停止采集

        // Stop grab imagenRet = MV_CC_StopGrabbing(handle);if (MV_OK != nRet){printf("Stop Grabbing fail! nRet [0x%x]\n", nRet);break;}

1.8 关闭相机并摧毁句柄

        // Close devicenRet = MV_CC_CloseDevice(handle);if (MV_OK != nRet){printf("ClosDevice fail! nRet [0x%x]\n", nRet);break;}// Destroy handlenRet = MV_CC_DestroyHandle(handle);if (MV_OK != nRet){printf("Destroy Handle fail! nRet [0x%x]\n", nRet);break;}

二、OpenCV相关操作

在RawDataFormatConvert中，最主要的功能是将连续采集的图片，从相机的缓冲区域转化OpenCV的Mat格式，并在屏幕上显示，因此我们可以利用Mat格式调用OpenCV的相关操作。

while (true){clock_t startTime, endTime;startTime = clock();nRet = MV_CC_GetImageBuffer(handle, &stImageInfo, 1000);if (nRet == MV_OK){printf("Get One Frame: Width[%d], Height[%d], nFrameNum[%d]\n",stImageInfo.stFrameInfo.nWidth, stImageInfo.stFrameInfo.nHeight, stImageInfo.stFrameInfo.nFrameNum);}else{printf("No data[0x%x]\n", nRet);free(pData);pData = NULL;break;}cv::Mat srcImage;srcImage = cv::Mat(stImageInfo.stFrameInfo.nHeight, stImageInfo.stFrameInfo.nWidth, CV_8UC1, stImageInfo.pBufAddr);cv::namedWindow("srcImage", 0);cv::resizeWindow("srcImage", 918, 768);cv::imshow("srcImage", srcImage);cv::waitKey(1);srcImage.release();nRet = MV_CC_FreeImageBuffer(handle, &stImageInfo);endTime = clock();std::cout << "Run Time:" << (double)(endTime - startTime) / CLOCKS_PER_SEC << "s" << std::endl;std::cout<< std::endl;}

根据上述代码，我们将ImageBuffer区域的数据转化为Mat格式，并且根据CV_8UC1格式，可知图像应为灰度图，这要与相机图像格式对应。

三、运行结果

运行结果如图所示：