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2016-05-19 10:00:10 -0600 received badge  Popular Question (source)
2013-10-12 17:09:03 -0600 asked a question Supported embedded linux platforms

Hello everybody :)

I started developing a computervision application (stitching, object detection, background substractor) using a Raspberry Pi.

I profiled my code and it seems that a lot of time is wasted with copying the images.

Are there any well supported/documented alternatives to the Raspberry Pi that would provide better performance? (-> higher framerate and/or image size)

On a sidenote: How big is the performance impact of NEON support and multiple cores? Is there are roadmap for supporting CUDA on ARM? (

The Ouya seems to have a good cost-performance ratio. Opinions?

2013-01-11 11:07:28 -0600 commented question openCV does not build on my RaspberryPi

You are correct. I am using Raspian.

2013-01-11 08:27:46 -0600 asked a question openCV does not build on my RaspberryPi

I get the following output when compiling opencv:

[ 18%] Built target opencv_flann
[ 18%] Built target opencv_highgui_pch_dephelp
[ 18%] Built target pch_Generate_opencv_highgui
Linking CXX shared library ../../lib/
/usr/bin/ld: /usr/local/lib/libx264.a(common.o): relocation R_ARM_MOVW_ABS_NC against `a local symbol' can not be used when making a shared object; recompile with -fPIC
/usr/local/lib/libx264.a: could not read symbols: Bad value
collect2: ld returned 1 exit status
make[2]: *** [lib/] Error 1
make[1]: *** [modules/highgui/CMakeFiles/opencv_highgui.dir/all] Error 2
make: *** [all] Error 2

I've been following this guide. What am I missing? :/

2012-12-27 08:33:10 -0600 received badge  Student (source)
2012-12-26 17:27:05 -0600 asked a question Advice on improving performance

I am developing for an embedded ARM system and I am looking for advice on improving overall performance.


What should one avoid when developing for performance? (e.g. what functions are slow)

How do you find out where you can improve your code? How to profile a opencv project under Linux?

What are fast algorithms for object detection?

Are there any code examples of fast implementations?

2012-12-20 14:22:20 -0600 asked a question Performance on Raspberry Pi for detecting humans

I would like to detect and track people using a Raspberry Pi, Model B v2 (512MB RAM) and a Logitech C310 webcam on a pan/tilt mount.

I experimented with the BackgroundSubtractorMOG2 which worked quite well, but stitching (to build a background for the entire range of vision) is to slow.

Now I am considering:

  1. Using BackgroundSubtractorMOG2 without stitching and only moving the camera in discrete steps (-45° , 0°, +45°), treating the three FoVs seperately.
  2. Using a fast algorithm for object detection. Maybe LBP?

Is it possible to detect people on a Raspberry Pi with LBP or some other algorithm in real time? Can a neural network be fast enough for this too?

2012-12-20 14:00:48 -0600 answered a question Encoding videos for opencv

I recompiled with ffmpeg but forgot to make install


2012-12-04 17:46:47 -0600 received badge  Supporter (source)
2012-12-04 17:46:34 -0600 commented answer Encoding videos for opencv

This is solved, but I am not allowed to close the question yet... It didn't work so I recompiled but forgot to "make install" -_- Everything works fine now...

2012-12-04 06:01:51 -0600 commented answer Encoding videos for opencv

For ccp-examle-bgfg_gmg even the original mjpeg videos work... it seems to be a problem with compiling. I do not understand, wh...

2012-12-03 17:31:56 -0600 commented answer Encoding videos for opencv

I am running out of ideas... are there any fool-proof video samples I could try? Maybe it's a problem with the code.

2012-12-03 14:48:10 -0600 commented answer Encoding videos for opencv

To what codec/format?

2012-12-03 14:28:52 -0600 received badge  Editor (source)
2012-12-03 14:28:25 -0600 asked a question Encoding videos for opencv

I would like to use video datasets to test my program, but unfortunately it does not work.

How do I encode them for the current version of opencv?

PS: It seems to be a problem with cmake (OpenCV examples work but own project doesn't). I am using the tutorial CMakeList.txt that does not compile including the codecs. Can you give me any pointers on how to correctly do this?