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Unable to display uvc_camera output without rqt

Hi, first post on here, getting into ROS day by day. Would appreciate some help on the following issue.

I finally figured out how to install and use the uvc_camera package to display the image coming from my Logitech C270 webcam. I wasn't able to run the launch file and create a node with libuvc so I went back to the deprecated version.

Anyways, I run the following command, which executes successfully

roslaunch uvc_camera camera_node.launch

Below is my launch file

<launch>
  <node pkg="uvc_camera" type="uvc_camera_node" name="uvc_camera" output="screen">
    <param name="width" type="int" value="320" />
    <param name="height" type="int" value="240" />
    <param name="fps" type="int" value="30" />
    <param name="frame" type="string" value="wide_stereo" />

    <param name="auto_focus" type="bool" value="False" />
    <param name="focus_absolute" type="int" value="0" />
    <!-- other supported params: auto_exposure, exposure_absolute, brightness, power_line_frequency -->

    <param name="device" type="string" value="/dev/video0" />
    <param name="camera_info_url" type="string" value="file://$(find uvc_camera)/example.yaml" />
  </node>
</launch>

What I'm having trouble with is viewing the raw_image with the following command:

rosrun image_view image_view image:=/image_raw

It just gives me a blank window screen that kinda shows the windows in the background of my screen (very buggy graphics), but nothing from my webcam.

I am able to view the image_raw with the following command, however.

rqt_image_view

Can someone explain to me why this is? Thanks in advance.

Asked by rational_galt on 2018-10-15 01:35:39 UTC

Comments

What kind of topics do you see when you execute "rostopic list" from the terminal?

Asked by msadowski on 2018-10-15 11:29:10 UTC

/camera_info /image_raw /image_raw/compressed /image_raw/compressed/parameter_descriptions /image_raw/compressed/parameter_updates /image_raw/compressedDepth /image_raw/compressedDepth/parameter_descriptions /image_raw/compressedDepth/parameter_updates /image_raw/theora /image_raw/theora/parameter_d

Asked by rational_galt on 2018-10-15 23:23:02 UTC

Answers