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Using Blue Robotics Low LIght USB cameras in ROV system

(Jacob) #21

You need to install a newer version of gstreamer from source. Unfortunately, this takes a few hours.

Manual Companion RPi Install?
(Dan Zimmerman) #22

OK, will do, thanks.

(Dan Zimmerman) #23

Thanks again, all working now.

(Jesper Christensen) #24

@jwalser Today I got the opportunity to test this camera in an oceanarium.
I turned off streaming and only saved the streams from two camera on a Raspberry Pi 3.
I seemed to get a lot of noise in the videos and a somewhat low quality even though I record in HD. I tried turning one of the camera off in order to inspect if it was I/O problems, but the result remained the same.
Here is a sample image:

It is taken from a video available at this dropbox link. It might not be very visible on this image. The environment in the tank provides plenty of light and it does not seem to saturate anywhere in this particular video.

Do you have any thoughts on this? I will be shooting all day tomorrow as well, and if I could get an enhanced result there I would be very happy :slight_smile:


(Jacob) #25

Can you try:

  1. manually adjusting the focus of the camera, by loosening the set screw
  2. Adjusting camera settings at (you will only be able to adjust the controls on the right hand column with your custom streaming script)

The noise on the right of the image appears to be due to very little light in that portion of the image vs the left hand side. The horizontal bands may be induced by the thrusters running. Were the thrusters running in this picture?

(Jesper Christensen) #26
  1. I will try adjusting focus when I get to open the tubes.
  2. Is that a local link?

I have no thrusters on in this tube. It only contains two cameras and a Raspberry Pi. And some weights to make it sink.

(Jacob) #27

Yes, if you are using our Raspberry Pi image, then there is a server running on the Pi.

How are you powering things?

(Jesper Christensen) #28

I am running a normal Jessie distro, so I don’t have that available.
I am using PoE with a 48V injector split into 5V 2.4A and ethernet in the tube.

(Jacob) #29

Hm, ok the horizontal lines/noise looks like it is caused by ripple in the power supply Can you add an LC filter, or try a different power supply and see if there is any difference?

Can you also try our pre-fab image and see if you see any difference?

(Jesper Christensen) #30

@jwalser Looking over some of the data I recorded last week, I am actually quite happy with the results. I do have a lot of motion-blur that reduces the quality in the video frame to frame. This is of course coursed by the low-light conditions and thereby longer integration time with auto-exposure on.
Could you send me the parameters for the cameras that you have obtained good low-light material with? Do you use auto-exposure or have you found a magic value to set it to?
And also, the documentation on the cameras or quite sparse - do you have a datasheet or a somewhat more detailed description you could make available?

/ Jesper

(Margus) #31


How much latency are you getting with this USB camera?

(Jacob) #32

The latency depends on a lot of factors and the processes/systems that transport the video data from the camera to the remote display.

On our ROVs the latency is around 150~200ms with the video displayed in QGC.

(rohit ) #33


how to record usb camera video with data and time in qgc ?



(Patrick José Pereira) #34


QGC has a record video button in the bottom right of the video widget.

You can find the videos with the recorded time and date in your documents folder: Documents/QGroundControl/Video/2017-11-12_19.04.21.mkv

There is currently no support for recording data and overlay on the video. For that you will need to use a screen recording application like windows game center.

(rohit ) #35

i want to record video with all the data showing on qgc .


(Eloi Droniou) #36

Hi rohit,

patricklectric mentioned that you need to use a screen recording application for this purpose. He suggested “windows game center”. Patrick, could you please send a link to this application? I could not find it on the web.

Alternatively, you may use something like screencapturer.com which is working fine for me.

(Patrick José Pereira) #37


You can take a further look about it here. This feature is from xbox app that is usually installed by default in windows.