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2014-07-29 16:04:50 -0500 asked a question visp_auto_tracker does not output pose data and unable to track properly

Hi all,

visp_auto_tracker was working perfectly fine for me until today...when I ran visp_auto_tracker, I got the message below repeatedly as the webcam tracked the QR code.

 *********** Parsing XML for Mb Edge Tracker ************ 
ecm : mask : size : 5
ecm : mask : nb_mask : 180
ecm : range : tracking : 10
ecm : contrast : threshold 5000
ecm : contrast : mu1 0.5
ecm : contrast : mu2 0.5
sample : sample_step : 4
sample : n_total_sample : 250
klt : Mask Border : 0
klt : Max Features : 10000
klt : Windows Size : 5
klt : Quality : 0.01
klt : Min Distance : 20
klt : Harris Parameter : 0.01
klt : Block Size : 3
klt : Pyramid Levels : 3
face : Angle Appear : 75
face : Angle Disappear : 75
camera : u0 : 325.03 (default)
camera : v0 : 219.983 (default)
camera : px : 523.553 (default)
camera : py : 520.561 (default)
(L0) !! /tmp/buildd/ros-hydro-visp-2.9.0-4precise-20140617-1429/src/camera/vpCameraParameters.cpp: get_K(#403) : 
     getting K matrix in the case of projection           with distortion has no sense
Tracking failed

     getting K matrix in the case of projection                   with distortion has no sense
Tracking done in 33.239 ms

When I check "rostopic echo /visp_auto_tracker/object_position", I saw that I was no longer getting any pose data from the webcam. The tracking markers that were supposed to show up on the debug display window were no longer there as well. I noticed there were only 8 markers at the corners of the QR code labelled: mi1, mi2, mi3, mi4, mo1, mo2, mo3, mo4. I'm kind of stumped since this problem came out of nowhere and I don't recall changing anything either. Any help is greatly appreciated. Thanks!

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2014-07-18 11:34:07 -0500 commented answer How to subscribe visp_auto_tracker to /usb_cam/image_raw/compressed?

Thank you for the response! Currently, I am not running any code, just rosrun usb_cam usb_cam_node and visp_auto_tracker via the above launch file...so I'm not sure where I can do the changes as you suggested.

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2014-07-16 14:15:47 -0500 asked a question How to subscribe visp_auto_tracker to /usb_cam/image_raw/compressed?

Hi all,

I am wondering if this is possible, since just subscribing to /usb_cam/image_raw causes a lot of lag, and the visp_auto_tracker debug display window will freeze up. Here is my launch file to run visp_auto_tracker (where I try to subscribe to /usb_cam/image_raw/compressed):

<launch>
  <!-- Launch the tracking node -->
  <node pkg="visp_auto_tracker" type="visp_auto_tracker" name="visp_auto_tracker" output="screen">
    <param name="model_path" type="string" value="$(find visp_auto_tracker)/models" />
    <param name="model_name" type="string" value="pattern" />
    <param name="debug_display" type="bool" value="True" />

    <remap from="/visp_auto_tracker/camera_info" to="/usb_cam/camera_info"/>
    <remap from="/visp_auto_tracker/image_raw" to="/usb_cam/image_raw/compressed"/>
  </node>
</launch>

But when I run this, I get this error in the terminal where I am running the usb_cam node:

[ERROR] [1405534682.215726942]: Client [/visp_auto_tracker] wants topic /usb_cam/image_raw/compressed to have datatype/md5sum [sensor_msgs/Image/060021388200f6f0f447d0fcd9c64743], but our version has [sensor_msgs/CompressedImage/8f7a12909da2c9d3332d540a0977563f]. Dropping connection.

So, is there a way to properly subscribe the visp_auto_tracker to /usb_cam/image_raw/compression? Appreciate any help, thanks!

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2014-07-09 10:47:51 -0500 commented question Problem displaying webcam on Beaglebone Black ROS Hydro

It works! I just had to view the images from a laptop instead

2014-07-09 10:45:25 -0500 commented answer Problem displaying webcam on Beaglebone Black ROS Hydro

I finally realized that! So while I ran usb_cam on the beaglebone, I ran rviz on a laptop to view the published images from usb_cam. So even with the conversion msg popping up, I can still view the image from the webcam.

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2014-06-12 09:48:15 -0500 asked a question Problem displaying webcam on Beaglebone Black ROS Hydro

Hi everyone,

I have Ubuntu 12.04 and ROS Hydro installed on a Beaglebone Black and I am trying to connect a webcam to it. When I do lsusb, i see the webcam listed and it is recognized as /dev/video0. However, when I run:

rosrun usb_cam usb_cam_node

I get this error at the bottom:

[ INFO] [1402520069.293107674]: Camera name: head_camera
[ INFO] [1402520069.296888674]: Camera info url: 
[ INFO] [1402520069.301380049]: usb_cam video_device set to [/dev/video0]

[ INFO] [1402520069.304736965]: usb_cam io_method set to [mmap]

[ INFO] [1402520069.307870465]: usb_cam image_width set to [640]

[ INFO] [1402520069.311110715]: usb_cam image_height set to [480]

[ INFO] [1402520069.314403132]: usb_cam pixel_format set to [mjpeg]

[ INFO] [1402520069.317508174]: usb_cam auto_focus set to [0]

[swscaler @ 0x3f640] No accelerated colorspace conversion found from yuv422p to rgb24.
[ INFO] [1402520069.502437715]: using default calibration URL
[ INFO] [1402520069.506553799]: camera calibration URL: file:///home/ubuntu/.ros/camera_info/head_camera.yaml
[swscaler @ 0x3fee0] No accelerated colorspace conversion found from yuv422p to rgb24.
[swscaler @ 0x3fee0] No accelerated colorspace conversion found from yuv422p to rgb24.
[swscaler @ 0x3fee0] No accelerated colorspace conversion found from yuv422p to rgb24.
[swscaler @ 0x3fee0] No accelerated colorspace conversion found from yuv422p to rgb24.
[swscaler @ 0x3fee0] No accelerated colorspace conversion found from yuv422p to rgb24.
[swscaler @ 0x3fee0] No accelerated colorspace conversion found from yuv422p to rgb24.

Is there a way to fix this conversion issue? Googling hasn't helped me much with this. I appreciate any kind of help...thanks!

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2014-06-11 15:11:23 -0500 commented answer Webcam does not display when using visp_auto_tracker

Thank you! After a bit of playing around with the calibration file, I was finally able to run that live video example launch file. Really appreciate your help! :)

2014-06-11 10:20:56 -0500 commented answer Webcam does not display when using visp_auto_tracker

I'm not entirely sure what you mean, but when i did rostopic echo /usb_cam/camera_info, i noticed the D matrix was empty and the K,P,R matrices are full of zeros, which is different from the matrices shown after I clicked commit..

2014-06-11 09:22:43 -0500 commented answer Problem installing packages on BeagleBone Black with ROS Hydro

Oh, I did not realize that. Thanks for the response.

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2014-06-10 16:07:22 -0500 asked a question Problem installing packages on BeagleBone Black with ROS Hydro

Hi everyone,

I'm having trouble installing packages in ROS Hydro on BeagleBone Black with Ubuntu ARM 12.04.

For example, when I tried to install vision_visp package, I did:

sudo apt-get install ros-hydro-vision-visp

But I get:

E: Unable to locate package ros-hydro-vision-visp

The same error seem to occur when I try installing other packages as well. There is no problem with the internet connection, since I can ping another computer, and also ssh from another computer into the Beaglebone. Could I have done something wrong during the Hydro or Ubuntu installation process?

Any help is much appreciated! Thank you.

2014-06-10 15:41:05 -0500 commented answer Webcam does not display when using visp_auto_tracker

But then, the video stream display window freezes and stops responding and nothing happens afterwards...

2014-06-10 15:38:58 -0500 commented answer Webcam does not display when using visp_auto_tracker

That is exactly what I did. When I click save, i get the msg: ('Wrote calibration data to', '/tmp/calibrationdata.tar.gz'). What exactly is the calculated reprojection error? After clicking commit,I get a result like the bottom of http://wiki.ros.org/camera_calibration/Tutorials/MonocularCalibration

2014-06-10 13:20:23 -0500 commented answer Webcam does not display when using visp_auto_tracker

I can't seem to get the calibration to fully finish. After i'm done with the checkerboard, I click "calibrate" and "save". After clicking "commit", the computer freezes, and eventually kills the process, so the calibration doesn't seem to get saved onto the webcam. Console just says "Killed"

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2014-06-10 09:04:07 -0500 commented answer Webcam does not display when using visp_auto_tracker

I see. Thanks for the tip!

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2014-06-09 10:42:32 -0500 asked a question Webcam does not display when using visp_auto_tracker

Hi everyone,

I am trying to get a Logitech webcam to work with visp_auto_tracker to do some QR tracking. I am running ROS Hydro on Ubuntu. I started off with usb_cam and that worked fine with the webcam, so now I am trying the live video example launch file (tracklive_usb.launch) on the wiki page at wiki.ros.org/visp_auto_tracker. The webcam light turns on, but there is no camera feed, and I get this error:

[ WARN] [1402326372.657815348]: Camera calibration file /home/toshiba/.ros/camera_info/head_camera.yaml not found.
terminate called after throwing an instance of 'std::runtime_error'
what():  uncalibrated camera
[visp_auto_tracker-1] process has died [pid 17186, exit code -6, cmd /opt/ros/hydro/lib/visp_auto_tracker/visp_auto_tracker /visp_auto_tracker/camera_info:=/usb_cam/camera_info /visp_auto_tracker/image_raw:=/usb_cam/image_raw __name:=visp_auto_tracker __log:=/home/toshiba/.ros/log/fc4ac0ee-eb3d-11e3-a916-70f1a177b603/visp_auto_tracker-1.log].
log file: /home/toshiba/.ros/log/fc4ac0ee-eb3d-11e3-a916-70f1a177b603/visp_auto_tracker-1*.log

So then I try to calibrate the camera with this line by following wiki.ros.org/camera_calibration/Tutorials/MonocularCalibration

rosrun camera_calibration cameracalibrator.py --size 8x6 --square 0.108 image:=/camera/image_raw camera:=/usb_cam

But I get this message:

('Waiting for service', '/usb_cam/set_camera_info', '...')
Service not found

I am pretty new to ROS having just started a few weeks ago, so I'm kind of stumped. Is it really a problem with calibration? Any help is much appreciated. Thanks!