OpenNi2+PCL显示彩色点云

###一、openni2使用摄像头获取图像步骤：

1.openni初始化
2.openni打开设备
3.创建数据流并设置数据流模式

二、转化点云步骤

1.使用openni从数据流读取一帧图像
2.使用openni从图像读取像素数据
3.处理数据，将结果存入点云

三、示例代码

#include <iostream> 
#include <OpenNI.h>
#include <pcl/common/common_headers.h>       // for pcl::PointCloud
#include <pcl/visualization/pcl_visualizer.h>

openni::Device mDevice;
openni::VideoStream mColorStream;
openni::VideoStream mDepthStream;

bool init(){
    // Initial OpenNI
    if(openni::OpenNI::initialize() != openni::STATUS_OK){
        std::cerr << "OpenNI Initial Error: "  << openni::OpenNI::getExtendedError() << std::endl;
        return false;
    }
    // Open Device
    if(mDevice.open(openni::ANY_DEVICE) != openni::STATUS_OK) {
        std::cerr << "Can't Open Device: "  << openni::OpenNI::getExtendedError() << std::endl;
        return false;
    }
    return true;
}

bool createColorStream() {
    if(mDevice.hasSensor(openni::SENSOR_COLOR)) {
        if(mColorStream.create(mDevice, openni::SENSOR_COLOR) == openni::STATUS_OK) {
            // set video mode
            openni::VideoMode mMode;
            mMode.setResolution(640, 480);
            mMode.setFps(30);
            mMode.setP