Recording of images fails

[teutobod]

I'm publishing image data from my webcam using:
ros2 run image_tools cam2image (link)

The images are published to a topic of type:
sensor_msgs/msg/Image

Then I start recording using:
ros2 bag record /image
[INFO] [rosbag2_storage]: Opened database 'rosbag2_2019_11_08-16_48_23'.
[INFO] [rosbag2_transport]: Listening for topics...
[INFO] [rosbag2_transport]: Subscribed to topic '/image'
[INFO] [rosbag2_transport]: All requested topics are subscribed. Stopping discovery...

But finally the recorded bag is empty!
ros2 bag info rosbag2_2019_11_08-16_48_23/
Files: rosbag2_2019_11_08-16_48_23.db3
Bag size: 16.3 KiB
Storage id: sqlite3
Duration: 0.0s
Start: Jan 1 1970 01:00:00.0 (0.0)
End Jan 1 1970 01:00:00.0 (0.0)
Messages: 0
Topic information:

System: Ubuntu 18.04.3 LTS
ROS2 Release: Eloquent

[Karsten1987]

Could that be related to #125? Can you verify with which QoS you're sending the images? If the topics are sent reliably, I would assume the topics being correctly recorded. However, when you send images via unreliable QoS rosbag2 currently can't record this.

[peterchen25]

According to here the default qos of this demo in "reliable"

[Karsten1987]

I think that wasn't actually accurate and just got fixed.

With that fix - sending images reliably - I am able to record images:

 ➭ ros2 bag info rosbag2_2019_11_11-17_01_24/

Files:             rosbag2_2019_11_11-17_01_24.db3
Bag size:          59.3 MiB
Storage id:        sqlite3
Duration:          8.838s
Start:             Nov 11 2019 17:01:24.791 (1573520484.791)
End                Nov 11 2019 17:01:33.629 (1573520493.629)
Messages:          269
Topic information: Topic: /image | Type: sensor_msgs/msg/Image | Count: 269 | Serialization Format: cdr

[teutobod]

Thanks for the update Karsten. Works now for me.