使用小觅相机录制数据集
文章目录
- 1 目的
- 2 方法
- 2.1 SDK
- 2.2 ROS bag
- 2.2.1 录制bag
- 2.2.2 从bag文件中提取数据
- 2.2.2.1 提取图像
- 2.2.2.2 提取IMU数据
- 3 相关核心代码
- 3.1 record.cc
- 3.2 dataset.h
- 3.3 dataset.cc
- 4 参考
1 目的
在不同场景录制不同条件的数据集，主要是为了方便进行系统的测试，相当于一个benchmark，给不同的算法提供一个相同的测试环境。
2 方法
2.1 SDK
首先，安装好小觅相机的SDK。
然后，使用SDK中提供的样例程序，录制数据集。
cd ~/MYNT-EYE-S-SDK/samples/_output/bin
./record
终端的输出信息：
程序默认在当前路径创建datase文件夹存储数据，数据集包括：
- left文件夹为左摄像头的图像，编码格式为png
- disparity文件夹为视差图
- deth文件夹为深度图
- motion.txt为IMU数据，格式为
seq, flag, timestamp, accel_x, accel_y, accel_z, gyro_x, gyro_y, gyro_z, temperature - 在left等文件夹中还有
stream.txt，存储图片的信息，格式为seq, frame_id, timestamp, exposure_time
如果想制作成KITTI，TUM，EuRoC等数据集的格式，需要对代码进行一些修改，改动应该不大，主要是路径和命名。
2.2 ROS bag
2.2.1 录制bag
首先，启动相机。
source ~/MYNT-EYE-S-SDK/wrappers/ros/devel/setup.bash
roslaunch mynt_eye_ros_wrapper display.launch
然后，录制bag，包括左目，右目和IMU数据。
rosbag record /mynteye/left/image_raw /mynteye/right/image_raw /mynteye/imu/data_raw
2.2.2 从bag文件中提取数据
如果只存储了bag文件，又想得到上面方式采集的数据，这时可以从bag文件中提取出图像和IMU数据。
2.2.2.1 提取图像
打开一个终端，从bag文件中提取图像：
rosrun image_view extract_images _sec_per_frame:=0.01 image:=/mynteye/left/image_raw
注意：如果输出的图片数量与使用rosbag info命令查询得到的数量不符，可以减小_sec_per_frame参数的值。
打开另一个终端，播放bag：
rosbag play data.bag
这种方式提取的图片的名称是从frame0000.jpg依次升序的，如果想图片名是时间戳，需要使用以下程序。
新建extract_images.py:
# coding:utf-8
#!/usr/bin/python
# Extract images from a bag file.
import roslib #roslib.load_manifest(PKG)
import rosbag
import rospy
import decimal
import cv2
from sensor_msgs.msg import Image
from cv_bridge import CvBridge
from cv_bridge import CvBridgeError
left_path = '/home/wb/MYNT-EYE-S-SDK/dataset/left/' # 左目图像的路径，需提前手动创建，也可以使用程序自动创建
right_path = '/home/wb/MYNT-EYE-S-SDK/dataset/right/'
class ImageCreator():
def __init__(self):
self.bridge = CvBridge()
with rosbag.Bag('/home/wb/MYNT-EYE-S-SDK/2020-08-05-23-05-50.bag', 'r') as bag: # 读取bag文件，注意设置正确的bag文件路径
for topic,msg,t in bag.read_messages():
if topic == "/mynteye/left/image_raw": # 左目图像的topic
try:
cv_image = self.bridge.imgmsg_to_cv2(msg,"bgr8")
except CvBridgeError as e:
print e
# %.6f表示小数点后带有6位，可根据精确度需要修改
timestr = "%.6f" % msg.header.stamp.to_sec()
image_name = timer + ".png" #图像命名：时间戳.png
cv2.imwrite(left_path + image_name, cv_image) # 保存图像
elif topic == "/mynteye/right/image_raw": # 右目图像的topic
try:
cv_image = self.bridge.imgmsg_to_cv2(msg,"bgr8")
except CvBridgeError as e:
print e
# %.6f表示小数点后带有6位，可根据精确度需要修改
timestr = "%.6f" % msg.header.stamp.to_sec()
image_name = timer + ".png" #图像命名：时间戳.png
cv2.imwrite(right_path + image_name, cv_image) # 保存图像
if __name__ == '__main__':
try:
image_creator = ImageCreator()
except rospy.ROSInterruptException:
pass
配置好路径后，执行：
python extract_images.py
2.2.2.2 提取IMU数据
rostopic echo -b 2020-08-05-23-05-50.bag -p /mynteye/imu/data_raw > imu_data.csv
当然，也可以扩展上面的Python代码，自定义IMU数据的内容。
3 相关核心代码
3.1 record.cc
#include 3.2 dataset.h
#ifndef MYNTEYE_TOOLS_DATASET_H_ // NOLINT
#define MYNTEYE_TOOLS_DATASET_H_
#pragma once
#include 3.3 dataset.cc
#include "dataset.h"
#include ::max_digits10)
#define IMAGE_FILENAME_WIDTH 6
MYNTEYE_BEGIN_NAMESPACE
namespace tools {
Dataset::Dataset(std::string outdir) : outdir_(std::move(outdir)) {
VLOG(2) << __func__;
if (!files::mkdir(outdir_)) {
LOG(FATAL) << "Create directory failed: " << outdir_;
}
}
Dataset::~Dataset() {
VLOG(2) << __func__;
for (auto &&it = stream_writers_.begin(); it != stream_writers_.end(); it++) {
if (it->second) {
it->second->ofs.flush();
it->second->ofs.close();
}
}
if (motion_writer_) {
motion_writer_->ofs.flush();
motion_writer_->ofs.close();
}
}
void Dataset::SaveStreamData(
const Stream &stream, const device::StreamData &data) {
auto &&writer = GetStreamWriter(stream);
auto seq = stream_counts_[stream];
writer->ofs << seq << ", " << data.img->frame_id << ", "
<< data.img->timestamp << ", " << data.img->exposure_time
<< std::endl;
if (data.frame) {
std::stringstream ss;
ss << writer->outdir << MYNTEYE_OS_SEP << std::dec
<< std::setw(IMAGE_FILENAME_WIDTH) << std::setfill('0') << seq << ".png";
if (data.frame->format() == Format::GREY) {
cv::Mat img(
data.frame->height(), data.frame->width(), CV_8UC1,
data.frame->data());
cv::imwrite(ss.str(), img);
} else if (data.frame->format() == Format::YUYV) {
cv::Mat img(
data.frame->height(), data.frame->width(), CV_8UC2,
data.frame->data());
cv::cvtColor(img, img, cv::COLOR_YUV2BGR_YUY2);
cv::imwrite(ss.str(), img);
} else if (data.frame->format() == Format::BGR888) {
cv::Mat img(
data.frame->height(), data.frame->width(), CV_8UC3,
data.frame->data());
cv::imwrite(ss.str(), img);
} else {
cv::Mat img(
data.frame->height(), data.frame->width(), CV_8UC1,
data.frame->data());
cv::imwrite(ss.str(), img);
}
}
++stream_counts_[stream];
}
void Dataset::SaveMotionData(const device::MotionData &data) {
auto &&writer = GetMotionWriter();
// auto seq = data.imu->serial_number;
auto seq = motion_count_;
writer->ofs << seq << ", " << static_cast<int>(data.imu->flag) << ", "
<< data.imu->timestamp << ", " << data.imu->accel[0] << ", "
<< data.imu->accel[1] << ", " << data.imu->accel[2] << ", "
<< data.imu->gyro[0] << ", " << data.imu->gyro[1] << ", "
<< data.imu->gyro[2] << ", " << data.imu->temperature
<< std::endl;
++motion_count_;
/*
if(motion_count_ != seq) {
LOG(INFO) << "motion_count_ != seq !" << " motion_count_: " << motion_count_
<< " seq: " << seq;
motion_count_ = seq;
}
*/
}
void Dataset::SaveStreamData(
const Stream &stream, const api::StreamData &data) {
auto &&writer = GetStreamWriter(stream);
auto seq = stream_counts_[stream];
writer->ofs << seq << ", " << data.img->frame_id << ", "
<< data.img->timestamp << ", " << data.img->exposure_time
<< std::endl;
if (!data.frame.empty()) {
std::stringstream ss;
ss << writer->outdir << MYNTEYE_OS_SEP << std::dec
<< std::setw(IMAGE_FILENAME_WIDTH) << std::setfill('0') << seq << ".png";
cv::imwrite(ss.str(), data.frame);
}
++stream_counts_[stream];
}
void Dataset::SaveMotionData(const api::MotionData &data) {
auto &&writer = GetMotionWriter();
// auto seq = data.imu->serial_number;
auto seq = motion_count_;
writer->ofs << seq << ", " << static_cast<int>(data.imu->flag) << ", "
<< data.imu->timestamp << ", " << data.imu->accel[0] << ", "
<< data.imu->accel[1] << ", " << data.imu->accel[2] << ", "
<< data.imu->gyro[0] << ", " << data.imu->gyro[1] << ", "
<< data.imu->gyro[2] << ", " << data.imu->temperature
<< std::endl;
motion_count_++;
/*
if(motion_count_ != seq) {
LOG(INFO) << "motion_count_ != seq !" << " motion_count_: " << motion_count_
<< " seq: " << seq;
motion_count_ = seq;
}
*/
}
Dataset::writer_t Dataset::GetStreamWriter(const Stream &stream) {
try {
return stream_writers_.at(stream);
} catch (const std::out_of_range &e) {
writer_t writer = std::make_shared<Writer>();
switch (stream) {
case Stream::LEFT: {
writer->outdir = outdir_ + MYNTEYE_OS_SEP "left";
} break;
case Stream::RIGHT: {
writer->outdir = outdir_ + MYNTEYE_OS_SEP "right";
} break;
case Stream::DEPTH: {
writer->outdir = outdir_ + MYNTEYE_OS_SEP "depth";
} break;
case Stream::DISPARITY: {
writer->outdir = outdir_ + MYNTEYE_OS_SEP "disparity";
} break;
case Stream::RIGHT_RECTIFIED: {
writer->outdir = outdir_ + MYNTEYE_OS_SEP "right_rect";
} break;
case Stream::LEFT_RECTIFIED: {
writer->outdir = outdir_ + MYNTEYE_OS_SEP "left_rect";
} break;
case Stream::DISPARITY_NORMALIZED: {
writer->outdir = outdir_ + MYNTEYE_OS_SEP "disparity_norm";
} break;
default:
LOG(FATAL) << "Unsupported stream: " << stream;
}
writer->outfile = writer->outdir + MYNTEYE_OS_SEP "stream.txt";
files::mkdir(writer->outdir);
writer->ofs.open(writer->outfile, std::ofstream::out);
writer->ofs << "seq, frame_id, timestamp, exposure_time" << std::endl;
writer->ofs << FULL_PRECISION;
stream_writers_[stream] = writer;
stream_counts_[stream] = 0;
return writer;
}
}
Dataset::writer_t Dataset::GetMotionWriter() {
if (motion_writer_ == nullptr) {
writer_t writer = std::make_shared<Writer>();
writer->outdir = outdir_;
writer->outfile = writer->outdir + MYNTEYE_OS_SEP "motion.txt";
files::mkdir(writer->outdir);
writer->ofs.open(writer->outfile, std::ofstream::out);
writer->ofs << "seq, flag, timestamp, accel_x, accel_y, accel_z, "
"gyro_x, gyro_y, gyro_z, temperature"
<< std::endl;
writer->ofs << FULL_PRECISION;
motion_writer_ = writer;
motion_count_ = 0;
accel_count_ = 0;
gyro_count_ = 0;
}
return motion_writer_;
}
} // namespace tools
MYNTEYE_END_NAMESPACE
4 参考
- https://github.com/slightech/MYNT-EYE-S-SDK
- https://mynt-eye-s-sdk-docs-zh-cn.readthedocs.io/zh_CN/latest/
- https://www.cnblogs.com/arkenstone/p/6676203.html
- https://blog.csdn.net/corfox_liu/article/details/50920332?locationNum=15
- https://blog.csdn.net/Draonly/article/details/74642747