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JakobEngel / dso_ros

ROS wrapper for dso
GNU General Public License v3.0
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Retrieving/Streaming Output Data #29

Open yikuangteh opened 6 years ago

yikuangteh commented 6 years ago

Hi

I would like to stream out the data that is being printed from the function given in the sampleOutputWrapper (pushDepthImageFloat) into, let's say, a Python script. Is there a way to do so? I tried to find the function in the Main and System codes but to no avail.

NikolausDemmel commented 6 years ago

You can add whatever output code you want in the output wrapper callback, so you can e.g. open a tcp connection or a Unix pipe and serialize the data, and then connect and deserialize in your python script.

Maybe one or the simple options is using ROS. Usw dso_ros and add an output wrapper where you publish the data you want in the respective callbacks. On the python side you have subscribers listening to those topics.

yikuangteh commented 6 years ago

Okay, thank you! Is it possible to get the data (Eg. Depth and coordinates of points) from the plotted graph in Pangolin and send the data as well? Do I do that within the OutputWrapper or within the programming file for Pangolin?

yikuangteh commented 6 years ago

I happened to see this post in the main DSO Github: https://github.com/JakobEngel/dso/issues/55

I couldn't make out how the values are related to what the camera is seeing other than the depth value on the last column. But I guess it's somewhat the thing that I needed to produce an output outside of Pangolin. Is it possible to output them as a data stream into a Python file? @ginko3

@NikolausDemmel I also understand that you've advised not to do any sort of processing in the OutputWrapper file, but is it still possible to do so? (Eg. Determining a depth value and passing commands to the ROS based on the value it gives)

NikolausDemmel commented 6 years ago

I also understand that you've advised not to do any sort of processing in the OutputWrapper file, but is it still possible to do so? (Eg. Determining a depth value and passing commands to the ROS based on the value it gives)

Yes, just that if you want real-time operation, you shouldn't do any long processing. If you don't care about realtime and run in "linearized" execution, it doesn't matter. Otherwise, what you can / should do is putting whatever data you need in some queue, and then have another thread processing the data from the queue and doing whatever you want.