# Stereo interface received non-stereo frame, exiting stereo

Source: https://forum.modalai.com/topic/2974/stereo-interface-received-non-stereo-frame-exiting-stereo
Category: General Questions (https://forum.modalai.com/category/2/general-questions)
Posted: 2023-12-20 09:37:43 UTC by cch
Replies: 3 · Views: 733

## cch · 2023-12-20 09:37:43 UTC

Hi, I'm using voxl2 with:

system-image: 1.5.5-M0054-14.1a-perf
kernel: #1 SMP PREEMPT Fri Mar 24 00:48:55 UTC 2023 4.19.125
hw version: M0054
voxl-suite: 0.9.5

I'm facing the same problem with Re: [Stereo interface received non-stereo frame](exiting stereo), where the stereo images and the disparity image are shown on voxl-portal. And every thing works fine after launching 'voxl-mpa-to-ros':

```
voxl2:~/.ros/log/1257f2ae-9f10-11ee-bc6c-00c0cab5947a$ roslaunch voxl_mpa_to_ros voxl_mpa_to_ros.launch
... logging to /home/root/.ros/log/19d7c026-9f16-11ee-86c1-00c0cab5947a/roslaunch-m0054-32592.log
Checking log directory for disk usage. This may take a while.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

started roslaunch server http://m0054:38073/

SUMMARY
========

PARAMETERS
 * /rosdistro: melodic
 * /rosversion: 1.14.13

NODES
  /
    voxl_mpa_to_ros_node (voxl_mpa_to_ros/voxl_mpa_to_ros_node)

auto-starting new master
process[master]: started with pid [32606]
ROS_MASTER_URI=http://localhost:11311

setting /run_id to 19d7c026-9f16-11ee-86c1-00c0cab5947a
process[rosout-1]: started with pid [32617]
started core service [/rosout]
process[voxl_mpa_to_ros_node-2]: started with pid [32620]

MPA to ROS app is now running

Found new interface: stereo
Found new interface: stereo_disparity
Found new interface: stereo_disparity_scaled
Found new interface: stereo_pc

```

I also checked the topic info in another terminal:

```
voxl2:/$ rostopic list 
/rosout
/rosout_agg
/stereo/left
/stereo/right
/stereo_disparity/left
/stereo_disparity/right
/stereo_disparity_scaled/left
/stereo_disparity_scaled/right
/stereo_pc
voxl2:/$ rostopic info /stereo/left
Type: sensor_msgs/Image

Publishers: 
 * /voxl_mpa_to_ros_node (http://m0054:41893/)

Subscribers: None

voxl2:/$ rostopic info /stereo_disparity/left
Type: sensor_msgs/Image

Publishers: 
 * /voxl_mpa_to_ros_node (http://m0054:41893/)

Subscribers: None

```

Everything looks great but a strange thing happens that: 1. If I use 'rostopic echo /stereo/left', the /stereo/left topic is subscribed and shows in terminal 2.If I use 'rostopic echo /stereo_disparity/left', the /stereo_disparity/left topic won't be subscribed and the 'voxl-mpa-to-ros' will crash after announcing that 'Stereo interface received non-stereo frame, exiting stereo':

```
voxl2:~/.ros/log/1257f2ae-9f10-11ee-bc6c-00c0cab5947a$ roslaunch voxl_mpa_to_ros voxl_mpa_to_ros.launch
... logging to /home/root/.ros/log/fafd37b2-9f15-11ee-bc54-00c0cab5947a/roslaunch-m0054-31666.log
Checking log directory for disk usage. This may take a while.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

started roslaunch server http://m0054:36119/

SUMMARY
========

PARAMETERS
 * /rosdistro: melodic
 * /rosversion: 1.14.13

NODES
  /
    voxl_mpa_to_ros_node (voxl_mpa_to_ros/voxl_mpa_to_ros_node)

auto-starting new master
process[master]: started with pid [31680]
ROS_MASTER_URI=http://localhost:11311

setting /run_id to fafd37b2-9f15-11ee-bc54-00c0cab5947a
process[rosout-1]: started with pid [31691]
started core service [/rosout]
process[voxl_mpa_to_ros_node-2]: started with pid [31694]

MPA to ROS app is now running

Found new interface: stereo
Found new interface: stereo_disparity
Found new interface: stereo_disparity_scaled
Found new interface: stereo_pc
Interface stereo_disparity now publishing
Stereo interface received non-stereo frame, exiting stereo
[voxl_mpa_to_ros_node-2] process has died [pid 31694, exit code -11, cmd /opt/ros/melodic/lib/voxl_mpa_to_ros/voxl_mpa_to_ros_node __name:=voxl_mpa_to_ros_node __log:=/home/root/.ros/log/fafd37b2-9f15-11ee-bc54-00c0cab5947a/voxl_mpa_to_ros_node-2.log].
log file: /home/root/.ros/log/fafd37b2-9f15-11ee-bc54-00c0cab5947a/voxl_mpa_to_ros_node-2*.log
^C[rosout-1] killing on exit
[master] killing on exit
shutting down processing monitor...
... shutting down processing monitor complete
done

```

I tried several times after rebooting voxl2. And I also tried to flash sdk 0.9.5 or turn off the voxl-portal. But I get the same result every time. It's hard to explain why this happens as the /stereo/left has the same type compared with /stereo_disparity/left, however, the /stereo/left can be subscribed but the /stereo_disparity/left can't. 

Any clue on what is going on?

## Reply by cch · 2023-12-20 09:42:41 UTC

There is also no 'voxl_mpa_to_ros_node-2*.log' for analyzing:

```
voxl2:~/.ros/log$ cd 1257f2ae-9f10-11ee-bc6c-00c0cab5947a/
voxl2:~/.ros/log/1257f2ae-9f10-11ee-bc6c-00c0cab5947a$ ls
master.log  roslaunch-m0054-30807.log  rosout-1-stdout.log  rosout.log
```

## Reply by planch98 · 2023-12-20 10:09:06 UTC (in reply to cch)

@cch try to update voxl-mpa-to-ros, they should have fixed it in https://gitlab.com/voxl-public/voxl-sdk/utilities/voxl-mpa-to-ros/-/commit/921db500db1f7109c3f2dde870a2a31ed0c38f2c

## Reply by cch · 2023-12-21 10:09:54 UTC (in reply to planch98)

@planch98 Thank you so much! I have solved the problem.