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View Code? Open in Web Editor NEWSoftware Development Kit for the Oxford Robotcar Dataset
License: Other
Software Development Kit for the Oxford Robotcar Dataset
License: Other
I'm confused about the stereo calibration.I download the camera models file but the files confused me.Could you tell me the stereo cameras calibrations?fx,fy,cy,cy ?and extrinsic?
I'm currently working on multiple camera coperation in the SLAM systems and I'm really interested in your dataset. But I'm a little confused on the extrinsic parameters in the provided SDK. I don't know the exact meaning of the parameters and I don't find any description either.
According to "SE3MatrixFromComponents.m", the parameters should be a translation vector followed by three Euler angles. And according to the parameters you provided, I guess all the transformation matrices from extrinsic parameters after processing with "SE3MatrixFromComponents.m" should be the transformations from the sensors to the stereo camera which is facing x direction. And the equations should be right:
Trans_4by4 = SE3MatrixFromComponents(sensor_parameters_1by6)
Corresponding_Point_in_stereo_frame = Trans_4by4 * Point_in_sensor_frame
So am I right or not? Could you help me?
And anther question is about the extrinsic parameter calibration of the cameras. Could you share me some experience about the extrinsic parameter calibration of the cameras since your paper doesn't talk much about that? And could you tell me the accuracy of the camera extrinsic calibraions? What's more, are there some camera extrinsic calibration sequences in the dataset? Thank you very much!
Just like the question says, how can I reverse the data back?I want to reverse the data from the motion compensation then using the raw data format to my work.
Could you please share the distortion coefficients that generates the mapping matrix in the model folder? Thank you!
Hi,
Thank you very much for sharing and publishing the dataset.
I have one problem. I want to use the stereo images, but notice that only the original camera parameter and distortion bin file are provided. I tried to undistort the images using your SDK. But how could I get the new camera parameter? Do you have the undistorted camera parameter file?
Thank you very much for your help
Kind Regards,
Ruihao
Using play_images.py, I can see the RGB images. How can I save this images into another folder? Please let me know. Thank you so much.
As the checkerboard sequences for calibration of the Grasshopper2 cameras are shown at http://robotcar-dataset.robots.ox.ac.uk/downloads/
Does anybody knows the length of the checkerboard for calibration?
How should I make this step:
As each ground truth odometry file does not begin at the same location in the urban environment, we manually selected (for each of the 32 trajectories) a moment during which the vehicle was stationary at a common point and manually aligned the ground traces. (Kidnapped radar, 2020)
The mono left camera extrinsic:
-0.0905 1.6375 0.2803 0.2079 -0.2339 1.2321
It seems from the car sensor location image that the translation should be close to:
-1.55 -0.59 -0.16.
It seems there is also a mistake with the mono right camera
Hello,
I ran ProjectLaserIntoCamera.m function but I got some erroneous results. For example, these are the results I get for timestamp=1400076055044636 (2014-05-14-13-59-05) for the centre camera:
It is clear that the samples over the pedestrians are not coherent, and also on the background.
Can you please check if you get the same output, and If not, can you please tell me what did I do wrong?
Thanks,
Adam
I know that "LoadImage" can do this for both perspective and fisheye images. But after that the fisheye image is rectified. Since what I want is the raw fisheye image, how to get a raw fisheye image with the noisy stripes removed?
I've recently started using this dataset and I've notices some strange misalignments between the various timestamps.
The images below show the global pose, relative pose (obtained from VO) and stereo frame at the same (or closest) timestamp. As seem, the INS and VO poses are completely different, with the stereo following the VO.
Do the timestamps need to be modified according to the start time of each sensor?
This is just a boundary error, but it is annoying since it happens for the last a few hundred frames of many drives when I try to generate the point cloud for each frame. I though many people might use your SDK, and it may be useful to point it out.
The error message will be "Matrix dimensions must agree" at the following line 79 of in file RelativeToAbsolutePoses.m
fractions = (pose_timestamps - vo_timestamps(lower_indices)')./...
(vo_timestamps(lower_indices+1)'-vo_timestamps(lower_indices)');
I figured out that it is caused by the pose_timestamps
it not bounded by vo_timestamps
. If the max pose_timestamp
is greater than the max vo_timestamps
, upper_index
in line 43 will be empty and upper_index
in line 46 will be 0.
We could add one function to bound the pose_timestamp
with vo_timestamps
, and avoid any changes in your original code.
Add the following line before line 98 at BuildPointcloud.m
laser_timestamps = boundLaserTimestamps(laser_timestamps, ins_file);
Added function is as follows:
function [ bounded_timestamps ] = boundLaserTimestamps( laser_timestamps, vo_file )
% Bound the laser timestamps by the max vo timestamps
% Usage: [ bounded_timestamps ] = boundLaserTimestamps( laser_timestamps, ins_file )
%
% INPUTS:
% laser_timestamps: array of UNIX timestamps from laser
% vo_file: csv file containing relative pose data
%
% OUTPUTS:
% bounded_timestamps: is the bounded by max vo_timestamps
%
% Author: Junsheng Fu ([email protected])
vo_file_id = fopen(vo_file);
headers = textscan(vo_file_id, '%s', 8, 'Delimiter',',');
vo_data = textscan(vo_file_id, '%u64 %u64 %f %f %f %f %f %f','Delimiter',',');
fclose(vo_file_id);
vo_timestamps = vo_data{1};
% only need to handle the up bound
end_timestamp = min(vo_timestamps(end), laser_timestamps(end,1));
end_index = find(laser_timestamps(:,1) <= end_timestamp, 1, 'last');
bounded_timestamps = laser_timestamps(1:end_index, :);
end
Hello,
similar to transform.py, in line.91 of build_pointcloud.py the divide operator '/' has to be replace by '//'
Best
Marc
Hi, I tried using this scrape_mrgdatashare.py
to download data as shown in the README, however, it kept failing.
The command that I used
python scrape_mrgdatashare.py --choice_sensors stereo_centre,vo --choice_runs_file example_list.txt --downloads_dir /Downloads --datasets_file datasets.csv --username <my-username> --password <my-password>
My example_list.txt
2014-12-17-18-18-43
The error message
requests.exceptions.ConnectionError: HTTPSConnectionPool(host='mrgdatashare.robots.ox.ac.uk', port=443):
Max retries exceeded with url: /
(Caused by NewConnectionError('<urllib3.connection.HTTPSConnection object at 0x7fae0c22b470>:
Failed to establish a new connection: [Errno 113] No route to host',))
It looked like a network error so I tried to download the GPS data from sequence 2015-02-03-19-43-11 from the website directly, using the link below:
https://mrgdatashare.robots.ox.ac.uk/download/?filename=datasets/2015-02-03-19-43-11/2015-02-03-19-43-11_gps.tar
but the address was unreachable.
Can you please help? Thanks!
great work! I have finded detection of curbs and lane in https://www.youtube.com/watch?v=Ski4W2eBh44&t=34s,I want to known how to download ground truth of lane and curb?
Hi!
I've tried using ProjectLaserIntoCamera.m on the 2014-12-16-09-14-09 run data from the dataset but get erroneous results when trying to utilize the visual odometry data.
I'm running the following code:
`root_data_path = 'some_path/oxford/2014-12-16-09-14-09';
image_dir = fullfile(root_data_path,'/mono_left');
laser_dir = fullfile(root_data_path,'/lms_rear');
ins_file = fullfile(root_data_path,'vo/vo.csv');
models_dir = 'some_path/robotcar-dataset-sdk/models';
extrinsics_dir = 'some_path/robotcar-dataset-sdk/extrinsics';
timestamp_file = 'some_path/oxford/2014-12-16-09-14-09/mono_left.timestamps';
timestamps = dlmread(timestamp_file);
timestamp_index = 1800;
image_timestamp = timestamps(timestamp_index,1);
ProjectLaserIntoCamera(image_dir, laser_dir, ins_file, models_dir, extrinsics_dir, image_timestamp)`
Changing line 98 in ProjectLaserIntoCamera.m instead gives the following results.
Have I done something wrong when calling the function or is there an error in the code?
Thanks,
maunzzz
Can you add the format of the extrinsics data with README.md in the extrinsics folder?
After downloaded the data I'm confused about what does the each number means in extrinsic file
Finally I found that how to use the extrinsic data in tranform.py
OpenCV Error: Unspecified error (The function is not implemented. Rebuild the library with Windows, GTK+ 2.x or Carbon support. If you are on Ubuntu or Debian, install libgtk2.0-dev and pkg-config, then re-run cmake or configure script) in cvShowImage, file /io/opencv/modules/highgui/src/window.cpp, line 583
Traceback (most recent call last):
File "play_radar.py", line 59, in <module>
cv2.imshow(title, vis * 2.) # The data is doubled to improve visualisation
cv2.error: /io/opencv/modules/highgui/src/window.cpp:583: error: (-2) The function is not implemented. Rebuild the library with Windows, GTK+ 2.x or Carbon support. If you are on Ubuntu or Debian, install libgtk2.0-dev and pkg-config, then re-run cmake or configure script in function cvShowImage
I use python3.5.2, The libgtk2.0-dev and pkg-config have been already installed. Thanks!
Hi,
I have found broken sections using rtk.csv
file with interpolate_ins_poses function.
I used this code snippet to generate the plots:
ins_path = os.path.join(dataset_dir, "images", dataset, "gps/rtk.csv")
timestamp_path = os.path.join(dataset_dir, "images", dataset, f"mono_{view}.timestamps")
pose_timestamps = np.loadtxt(timestamp_path)[:, 0].tolist()
origin_timestamp = pose_timestamps[0]
print('Interpolating poses...')
insext = np.loadtxt(os.path.join('robotcar_helper/extrinsics', f'mono_{view}.txt')).tolist()
mtx = transform.build_se3_transform(insext)
T_I_Cx = pose.fromMatrix(np.asarray(mtx)).inverse()
T_Cx_C = pose.yRotationDeg(90) * pose.zRotationDeg(90)
T_I_C = T_I_Cx * T_Cx_C
T_W_I0 = pose.xRotationDeg(180)
T_I0_I = interpolate_poses.interpolate_ins_poses(
ins_path, pose_timestamps[1:], origin_timestamp, use_rtk=True)
T_I0_I = [pose.fromMatrix(np.asarray(i)) for i in T_I0_I]
T_W_Cs = [T_W_I0 * i * T_I_C for i in T_I0_I]
t_W_Cs = np.array([T_W_C.t.ravel() for T_W_C in T_W_Cs])
plt.scatter(t_W_Cs[:, 1], t_W_Cs[:, 0], marker='.', s=4)
plt.axes().set_aspect('equal')
plt.grid()
plt.show()
The traversal used in this example is 2014-11-28-12-07-13
.
I have also direclty plot the poses using northing/easting data provided in the rtk.csv
file an I have observed similar issues at similar sections of the traversal.
In this dataset, the mono images (left | rare | right) contain only 164 samples (after extraction) which correspond to a very short straight path and they do not fit the groundtruth provided :
However, stereo images fit the path!
Is there some chunks missing for mono camera?
Cheers,
Hi,
I want to convert the timestamps provided into ROS time stamp format (seconds, nanoseconds)
But if I use a standard conversion using rospy from_seconds() throws error with the timestamps.
If I try to convert the timestamp to human readable date time using python time.ctime, I get strange dates
Thu Jan 9 23:25:05 44368617 Fri Jan 10 04:58:15 44368617 Fri Jan 10 10:32:04 44368617 Fri Jan 10 16:06:19 44368617 Fri Jan 10 21:40:35 44368617 Sat Jan 11 03:14:47 44368617
Anyone else have issues with this?
I would like to know the resolution of the timestamps so I can split it into seconds/microseconds from the unix timestamp provided.
Hello,
In line.84 of build_pointcloud.py, the timestamps[i] should be timestamps[i+1] as the len(poses) isn't equal to len(timestamps). The timestamps' value has been changed by function line.72 (interpolate_ins_poses) or line.75 (interpolate_vo_poses) due to the operation of requested_timestamps.insert(0, origin_timestamp) in line.102 of interpolate_poses.py.
Besides, in line.142 of interpolate_poses.py, the divide operator '//' in fractions should be replaced by '/'.
Best,
Bing
Hi, I would like to know how to use the processed data of point cloud.
How many components of this .bin
file?
(I guss x,y,z,r or any else? I would like to plot the point cloud)
Thanks in advance!
Hello,
Thank you for providing this dataset and this associated toolboxe.
I only have one question about the measurement unit used to describe reflectance associated to the points cloud acquired with the rear and front LIDAR (for example returned by the function build_pointcloud). What does the reflectance value returned represent?
Usually reflectance is a percentage of reflected light for a given material, but in your function the value of reflectance does not represent a percentage. With little inspection I find that values are between 101 and ~2000, with a mean value around 400.
Thank you per advance for your answer.
In the dataset page, it said,
LIDAR:
2 x SICK LMS-151 2D LIDAR, 270° FoV, 50Hz, 50m range, 0.5° resolution
1 x SICK LD-MRS 3D LIDAR, 85° HFoV, 3.2° VFoV, 4 planes, 12.5Hz, 50m range, 0.125° resolution
when I run the build_point cloud script with same parameter using /lms_front and /ldmrs laser scan folder, I find 2D LIDAR data provide more information in vertical axis than 3D LIDAR, it looks like below, first pic is /lms_front result and second pic is /ldmrs result.
I saw a sequence which had jumbled up timestamps in the INS file. What's the best way to handle this?
Hi
I can't find the vo.csv
files in the data, can you please provide the path for these files?
Thanks
in line 140 in transform.py in the function so3_to_quaternion
the function xrange no longer exists in python 3. its just range
Best Marc
Thank you so much for your great work, sir.
I am having some troubles when applying with other version like Velodyne-32c. I wonder why do you know the range resolution is "0.002" here ? Is this described in the document?
https://github.com/ori-mrg/robotcar-dataset-sdk/blob/master/python/velodyne.py#L21
I've found a few sequences don't have their timestamps of GPS/INS and fisheye camera synchronized. For example the sequence http://robotcar-dataset.robots.ox.ac.uk/datasets/2014-06-23-15-36-04/. It seems that in the sequence when GPS/INS has already turned around at the end of the sequence, the fisheye camera is still a few seconds from the turn. But most of the sequences are well synchronized.
Hi Robotcar Dataset Team,
I am using the Robotcar dataset in Opencv ,vsual studio.I have got problem in the conversion of the Raw bayer stereo image(pattern='gbrg' ) to Mat rgb image( cvtColor(); ).
Mat image(height,width, CV_8UC1, Scalar(0,0,255));
image = imread("C:\Users\u20w21\Desktop\bayer.png");
Mat image2;
cvtColor( image, image2, COLOR_BayerRG2RGB)
...........
But i get an error with cv::demosaic function.Could you please help me with the problem.
I am using python2.7, and the typing-3.7.4.1 package has been installed successfully.
Traceback (most recent call last):
File "play_radar.py", line 17, in <module>
from radar import load_radar, radar_polar_to_cartesian
File "/home/scopus/Downloads/robotcar-dataset-sdk-3.0/python/radar.py", line 20
def load_radar(example_path: AnyStr) -> Tuple[np.ndarray, np.ndarray, np.ndarray, np.ndarray, float]:
^
SyntaxError: invalid syntax
Should I use python3? Thanks!
May I know what kind of algorithm is used in pose interpolation?
The script produces pretty good pointclouds with ins data, but if I switch to the provided rtk groundtruth, something is wrong because I get an almost planar result along the ground truth trajectory.
In the interpolatePoses file it seems wierd that you assume a header with length of 24 because the rtk header is shorter than the previously used ins header. I changed this bit, but it still doesn't work, although with this change it produces results.
Please provide a short example of how the script should be used, if I am using it wrong.
Excuse me, i know you've provided sdk using matlab or python, but i want to ask if you have bag files for ros or any ways to get the bag files? Thanks a lot.
File "robotcar-dataset-sdk-3.1\robotcar-dataset-sdk-3.1\python\build_pointcloud.py", line 21, in
from velodyne import load_velodyne_raw, load_velodyne_binary, velodyne_raw_to_pointcloud
File "..\robotcar-dataset-sdk-3.1\robotcar-dataset-sdk-3.1\python\velodyne.py", line 33
def load_velodyne_binary(velodyne_bin_path: AnyStr):
^
SyntaxError: invalid syntax
When running build_pointcloud.py, I am using Python2.7. should I be using Python3? thanks!
Hello,
It seems that the line 147 in Camera_Model.py no longer works with python 3.
lut = lut.reshape([2, lut.size / 2])
It can easily be fixed by using
lut = lut.reshape([2, lut.size // 2])
This happens because Python 3 does not auto convert floats to integers in division
Best,
Marc
Dear Authors,
Thanks for your public dataset. We are trying to understand how the roll pitch yaw euler angles are computed relative to the UTM zone 30U.
For instance, from the /oxford/rtk/2014-11-11-11-06-25/rtk.csv, we find its first row,
timestamp,latitude,longitude,altitude,northing,easting,down,utm_zone,velocity_north,velocity_east,velocity_down,roll,pitch,yaw
1415704028184063,51.7605920064,-1.2612119076,111.316208,5735841.4578097975,620000.1836618409,-111.316208,30U,0.004,0.004,0.001,-0.01779099999969897,-0.006712000000142968,-0.09384140718030262
In the matlab and python code, we find that the pose of the body frame (B) relative to the world frame (W) is computed as
W_T_B = SE3MatrixFromComponents(northing, easting, down, roll, pitch, yaw).
From this website tool, I have confirmed that the northing and easting coordinates are relative to a coordinate frame (F) whose origin is at the equator with longitude -3 degree. To conform to the NED frame convention, the F frame can has its x along north, its y along east, and its z up. The transverse Mercator projection is understandable for the positions.
But for the orientation, I am baffled. As I understand, the F frame and the local level NED frame (N) differs in north direction by about 51.76 degrees in space.
Are these euler angles computed by waypoint inertial explorer (IE), relative to the local level NED frame (N) (which moves with the car) or relative to the F frame?
From my experience with IE, it outputs the roll pitch heading in the local level ENU frame by default.
But the SE3MatrixFromComponents() function implies that the euler angles are relative to the F frame.
If the euler angles are relative to the F frame, how do you transform the orientation from the N frame to the F frame?
Undefined function or variable 'yticks'.
Error in PlayRadar (line 73)
yticklabels(azimuths(yticks));
I use matlab R2015a in windows 10.
Regarding bumblebee, I noticed https://github.com/ori-mrg/robotcar-dataset-sdk/tree/master/models only has Pinhole intrinsic calibration for stereo_narrow_left. stereo_narrow_right, stereo_wide_left, stereo_wide_right.
However, the camera images are stored as stereo/left stereo/right and stereo/centre.
According to the paper:
stereo_narrow_<left/right>.txt
are for the the stereo/centre
and stereo/right
images.
stereo_wide_<left/right>.txt
are for the the stereo/left and stereo/right images.
So are there two intrinsic calibrations for stereo/right (stereo_narrow_right.txt and stereo_wide_right.txt)? What about intrinsic info for treating stereo/right as a monocular camera?
If for instance I feed images from one of these lenses to a visual odometry algorithm that works on monocular images, which Pinhole fx fy cx cy
values would be correct?
Hi @mttgdd
I am wondering if it is possible to build the global point cloud for each scan within the world coordinate system ? and is it possible to obtain the absolute pose for each camera?
the key is that we would like to use your dataset in a way, where the ground truth pose of the cameras (or practically of the vehicle body, or some sensor, that we have a precise relative pose to from each camera) should be available relative to the pointcloud!
So practically we need to be able to merge all the pointclouds (the individual scans) into one big data, and project it precisely on any selected image frame, perspective stereo or omnidirectional camera image also.
Can you please elaborate if you consider these details can be obtained from your dataset?
Thank you in advance for your kind help,
Best regards,
Hichem
Hi,
Could I know which file contains the camera intrinsic for stereo_centre after the undistortion? Is it stereo_narrow_left.txt ?
Thank you.
Hi, RobotCar Team,
Firstly, thank you for your great dataset!
I followed the https://robotcar-dataset.robots.ox.ac.uk/documentation/#pointcloud-projection-into-images to project pointcloud into images using the Python API provided by the SDK. However, the result seems incorrect as the attachment shows. The code is also in the attachment. Do you have any suggestions?
The code is:
################################################################################
#
# Copyright (c) 2017 University of Oxford
# Authors:
# Geoff Pascoe ([email protected])
#
# This work is licensed under the Creative Commons
# Attribution-NonCommercial-ShareAlike 4.0 International License.
# To view a copy of this license, visit
# http://creativecommons.org/licenses/by-nc-sa/4.0/ or send a letter to
# Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.
#
################################################################################
import os
import re
import numpy as np
import matplotlib.pyplot as plt
import argparse
sys.path.append('../dataset_loaders')
from robotcar_sdk.build_pointcloud import build_pointcloud
from robotcar_sdk.transform import build_se3_transform
from robotcar_sdk.image import load_image
from robotcar_sdk.camera_model import CameraModel
image_dir='../data/deepslam_data/RobotCar/loop_ldmrs/2014-06-26-09-24-58/stereo/centre/'
laser_dir='../data/deepslam_data/RobotCar/loop_ldmrs/2014-06-26-09-24-58/ldmrs'
poses_file='../data/deepslam_data/RobotCar/loop_ldmrs/2014-06-26-09-24-58/vo/vo.csv' # or '../data/deepslam_data/RobotCar/loop_ldmrs/2014-06-26-09-24-58/gps/ins.csv' #
models_dir='../data/robotcar_camera_models'
extrinsics_dir='/mnt/lustre/sunjiankai/App/robotcar-dataset-sdk/extrinsics/'
save_dir='../data/deepslam_data/RobotCar/loop_ldmrs/2014-06-26-09-24-58/depth/'
# args = parser.parse_args()
model = CameraModel(models_dir, image_dir)
extrinsics_path = os.path.join(extrinsics_dir, model.camera + '.txt')
with open(extrinsics_path) as extrinsics_file:
extrinsics = [float(x) for x in next(extrinsics_file).split(' ')]
G_camera_vehicle = build_se3_transform(extrinsics)
G_camera_posesource = None
poses_type = re.search('(vo|ins)\.csv', poses_file).group(1)
if poses_type == 'ins':
with open(os.path.join(extrinsics_dir, 'ins.txt')) as extrinsics_file:
extrinsics = next(extrinsics_file)
G_camera_posesource = G_camera_vehicle * build_se3_transform([float(x) for x in extrinsics.split(' ')])
else:
# VO frame and vehicle frame are the same
G_camera_posesource = G_camera_vehicle
print('G_camera_posesource: ', G_camera_posesource)
timestamps_path = os.path.join(image_dir, os.pardir, model.camera + '.timestamps')
if not os.path.isfile(timestamps_path):
timestamps_path = os.path.join(image_dir, os.pardir, os.pardir, model.camera + '.timestamps')
timestamp_list = []
with open(timestamps_path) as timestamps_file:
for i, line in enumerate(timestamps_file):
timestamp_list.append(int(line.split(' ')[0]))
for timestamp in timestamp_list[1000:]:
pointcloud, reflectance = build_pointcloud(laser_dir, poses_file, extrinsics_dir,
timestamp - 1e7, timestamp + 1e7, timestamp)
pointcloud = np.dot(G_camera_posesource, pointcloud)
print('pointcloud.shape: ', pointcloud[:, 0].max(), pointcloud[:, 1].max(), pointcloud[:, 2].max(), pointcloud[:, 0].min(), pointcloud[:, 1].min(), pointcloud[:, 2].min())
image_path = os.path.join(image_dir, str(timestamp) + '.png')
image = load_image(image_path, model)
uv, depth = model.project(pointcloud, image.shape)
plt.imshow(image)
plt.hold(True)
plt.scatter(np.ravel(uv[0, :]), np.ravel(uv[1, :]), s=2, c=depth, edgecolors='none', cmap='jet')
plt.xlim(0, image.shape[1])
plt.ylim(image.shape[0], 0)
plt.xticks([])
plt.yticks([])
plt.show()
Thank you!
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