# 深度精度示例-DepthUnitControl

功能描述：演示获取深度精度操作，显示深度图像，输出深度精度，并通过ESC_KEY键退出程序

>本示例基于C++ High Level API进行演示

创建Pipeline及流配置,并通过Pipeline获取设备

// Create a pipeline with default device
ob::Pipeline pipe;

// Get the device inside the pipeline
auto device = pipe.getDevice()

检查获取深度精度的方式

bool changeDepthUnitFlag = false;
// check the way to adjust depth unit
if(device->isPropertySupported(OB_PROP_DEPTH_PRECISION_LEVEL_INT, OB_PERMISSION_READ_WRITE)) {
    // change depth unit by adjust the depth precision level
    changeDepthUnitFlag = changeDepthUnit(device);
}
else if(device->isPropertySupported(OB_PROP_DEPTH_UNIT_FLEXIBLE_ADJUSTMENT_FLOAT, OB_PERMISSION_READ_WRITE)) {
    // for some models (Such as G300 series), user can adjust the depth unit by adjusting the depth unit flexible adjustment property
    changeDepthUnitFlag = changeDepthUnitFlexible(device);
}
else {
    std::cout << "Current device not support adjust depth unit, use the default depth unit 1mm" << std::endl;
    changeDepthUnitFlag = true;
}

计算深度值

// For Y16 format depth frame, print the distance of the center pixel every 30 frames
if(depthFrame->index() % 30 == 0 && depthFrame->format() == OB_FORMAT_Y16) {
    // Convert depth values to 1mm precision
    auto rstImageData = convertDepthFrameUnitTo1mm(depthFrame);

    uint32_t  width          = depthFrame->width();
    uint32_t  height         = depthFrame->height();
    uint16_t  centerDistance = rstImageData.data()[width * height / 2 + width / 2];

    // Attention: if the distance is 0, it means that the depth camera cannot detect the object（may be out of detection range）
    std::cout << "The depth frame center value is " << centerDistance << " mm. " << std::endl;

释放资源，退出程序。

pipe.stop();

预期输出：