C++手写PCD文件

前言

一般pcd读写只需要调pcl库接口，直接用pcl的结构写就好了

这里是不依赖pcl库的写入方法
主要是开头写一个header
注意字段大小，类型不要写错

结构定义

写入点需要与header中定义一致
这里用的RoboSense的结构写demo
加了个1字节对齐

struct PointXYZIT {float x;float y;float z;uint16_t intensity;double timestamp;
} __attribute__((packed));template <typename PointType>
class PointCloudT {public:typedef PointType PointT;typedef std::vector<PointT> VectorT;uint32_t height = 0;uint32_t width = 0;double timestamp = 0.0;uint32_t seq = 0;VectorT points;
};

代码实现

int record_pcd(PointCloudT<PointXYZIT> &point_cloud) {static int frame_id = 0;frame_id++;std::string pcd_file = "frame_" + std::to_string(frame_id) + ".pcd";int fd = open(pcd_file.c_str(), O_WRONLY | O_CREAT | O_TRUNC, 0644);const char *pcd_header ="# .PCD v.7 - Point Cloud Data file format\n""FIELDS ""x y z intensity timestamp\n""SIZE 4 4 4 2 8\n""TYPE F F F U F\n""COUNT 1 1 1 1 1\n""WIDTH %zu\n""HEIGHT 1\n""VIEWPOINT 0 0 0 1 0 0 0\n""POINTS %zu\n""DATA binary\n";char header_buffer_[400];memset(header_buffer_, 0, sizeof(header_buffer_));uint64_t write_size =snprintf(header_buffer_, sizeof(header_buffer_), pcd_header, point_cloud.width, point_cloud.width);assert(write_size > 0 && write_size < sizeof(header_buffer_));int r = write(fd, header_buffer_, write_size);assert(r >= 0);for (int i = 0; i < point_cloud.width; i++) {r = write(fd, &point_cloud.points[i], sizeof(PointXYZIT));assert(r >= 0);}close(fd);fd = -1;return 0;
}