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This page describes experiments carried out to create an embedded video processing unit based on the OMAP3530 application processor from Texas Instruments using Gumstix Overo COMs. The work was done within the Embedded Video Processing and Radio Unit project and is now considered finished. Logbook is on the talk page.

Development continues in Romit2 VPU.


  • Capture video from one or more cameras
  • Compress and multiplex the videos with telemetry into a single transport stream suitable for transmission over the air
  • Process incoming telcommands

First flight on amateur rocket

The objectives of this flight are:

  1. To test the Gumstix Overo Fire under high acceleration (6g)
  2. To capture images and/or video during the flight

We learned about an opportunity to fly onboard an amateur rocket (up to 3 km high). Flight will take place on October 3, 2010. Time is very short so we will be focusing on getting the Gumstix Overo Fire up and running, and have it record video during the flight. No real time video downlink.

System overview


Operating principle:

  1. After power on system boots Linux
  2. WiFi and Bluetooth are switched off
  3. Video capture script begins
 gst-launch -v v4l2src num-buffers=18000 (TBC) ! image/jpeg,width=640,height=480,framerate=30/1 !\
   avimux ! filesink location="video-%d.avi" 1> stdout-%d.log 2> stderr-%d.log


OS version: Angstrom 2010.7-test-20100923

Power budget

We have about 7 watts at our disposal.

Gumstix Overo Fire (WiFi and BT off) + Tobi expansion board + Logitech Webcam Pro 9000 consumes less than 500 mA at 5 VDC

Mass budget

The weight of electronics, camera, battery and wires not including the mounting hardware is approximately 200 grams.

Results & Conclusions

  1. We worked very well as a team
  2. Gumstix Overo Fire survived a crash landing from 500 meters (TBC if still working properly)
  3. USB interface on Gusmtix Overo Fire is too slow for HD (even in MJPG mode). Max throughput appears to be around 10-15 Mbps.
  4. For future UVC setups, a guvcview-like app to control all camera settings will be very useful.
  5. The hacked USB OTG interface eliminating the powered hub did not work well. After a while, the pipeline would stop due to a device I/O error
  6. The simple Gstreamer pipeline does not seem to be sufficient. While recording, every now and then there is a "jump" in the video suggesting that there is some performance issue somewhere (disk I/O, buffering?)
  7. When using SD cards, remember to add a piece of tape securing the card to the socket!

Damage due to crash landing

TobiConnector-001.jpg TobiConnector-002.jpg OveroFireConnector-001.jpg OveroFireConnector-002.jpg


Task Status
Get Gumstix Overo Fire up and running
  • Monitor, keyboard, mouse
  • Ethernet when using Tobi expansion board
Update image and boot from microSD 100%
Disable WiFi[1][2] 100%
Disable Bluetooth[3] 100%
Flash updated image to NAND Next time
Power consumption (with and without WiFi and BT)
  • During boot: 250 mA
  • After boot with WiFi & BT: 400 mA
  • After boot with WiFi & BT signals off[4]: 210 mA

Measurements done with Overo Fire on the Summit board.

Development environment Next time
Hardware DSP Next time



  1. Gumstix users wiki: Overo Wifi
  2. Gumstix users wiki: Creating an Ad-hoc Network
  3. Gumstix users wiki: Bluetooth
  4. Gumstix Overo: Connector Overview & Design Information. See in particular Signals PDF.
  5. Installing OMAP DVSDK on Gumstix Overo

See also Embedded Video Processing and Radio Unit



Complete YouTube playlist