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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. This is one branch of the Embedded Video Processing and Radio Unit project. Logbook is on the talk page.


  • 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 (TBD g)
  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

Desktop Image

Out of date

 root@overo:~# df -h
 Filesystem                Size      Used Available Use% Mounted on
 /dev/root                 1.8G    595.2M      1.1G  35% /
 devtmpfs                245.0M    188.0K    244.8M   0% /dev
 tmpfs                    40.0K         0     40.0K   0% /mnt/.splash
 none                    245.0M    188.0K    244.8M   0% /dev
 /dev/mmcblk0p2            1.8G    595.2M      1.1G  35% /media/mmcblk0p2
 /dev/mmcblk0p1           38.6M      3.2M     35.3M   8% /media/mmcblk0p1
 tmpfs                   245.0M      1.5M    243.5M   1% /var/volatile
 tmpfs                   245.0M         0    245.0M   0% /dev/shm
 tmpfs                   245.0M         0    245.0M   0% /media/ram
 root@overo:~# free -k
              total       used       free     shared    buffers     cached
 Mem:        501752     103500     398252          0       7784      59172
 -/+ buffers/cache:      36544     465208
 Swap:            0          0          0

Console image

'Out of date

 root@overo:~# df -h
 Filesystem                Size      Used Available Use% Mounted on
 /dev/root                 1.8G    154.7M      1.5G   9% /
 devtmpfs                118.1M    188.0K    117.9M   0% /dev
 none                    118.1M    188.0K    117.9M   0% /dev
 /dev/mmcblk0p2            1.8G    154.7M      1.5G   9% /media/mmcblk0p2
 /dev/mmcblk0p1           38.6M      3.2M     35.3M   8% /media/mmcblk0p1
 tmpfs                   118.1M    344.0K    117.8M   0% /var/volatile
 tmpfs                   118.1M         0    118.1M   0% /dev/shm
 tmpfs                   118.1M         0    118.1M   0% /media/ram
 root@overo:~# free -k
              total       used       free     shared    buffers     cached
 Mem:        241856      45052     196804          0       3900      26996
 -/+ buffers/cache:      14156     227700
 Swap:            0          0          0


General tasks

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%
Flash updated image to NAND TBC
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
  • Camera: TBD

Measurements done with Overo Fire on the Summit board.

Development environment
Hardware DSP

For flight

Task Status
Console image
  • Standard Gumstix console image
  • Minimal quick-booting image[5]
Select software to capture and save video from camera during flight

Gstreamer pipeline capturing JPG to AVI selected

Management software
  • executes gstreamer pipeline in a loop
  • Gstreamer pipeline capture 10 minutes of video (length TBC)
  • Redirect stdout and stderr to files
Pinto-TH breakout board Canceled
Using Summit due to need for TTY
Disable WiFi and BT 95%
  • Two 3.7 V 1 Ah LiPo batteries selected
  • Switching 5V regulator
Mounting hardware
Dry run using the Summit board

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.


  1. USB interface on Gusmtix Overo Fire is too slow for HD (even in MJPG mode). Max throughput appears to be around 10-15 Mbps.
  2. For future UVC setups, a guvcview-like app to control all camera settings will be very useful.



  1. Gumstix users wiki: Overo Wifi
  2. Gumstix users wiki: Creating an Ad-hoc Network
  3. Gumstix users wiki: Bluetooth
  4. 4.0 4.1 Gumstix Overo: Connector Overview & Design Information. See in particular Signals PDF.
  5. Minimal, quick booting Gumstix image and other resources

See also Embedded Video Processing and Radio Unit



Complete YouTube playlist