I am rather new to OpenCV and image processing in general. I am looking into background subtraction to facilitate motion tracking (people counting). Looking at the openCV documentation on background subtracting, GMG gives rather nice results. Also when looking at a video comparing the methods, I feel that GMG gives the best results, at least for my purpose.
I installed the latest version of opencv to use with python3 thus:
git clone --depth=1 https://github.com/Itseez/opencv.git
cd opencv
mkdir build
cd build
cmake -DBUILD_opencv_python3=YES -DBUILD_opencv_python2=NO -DINSTALL_PYTHON_EXAMPLES=YES -DPYTHON3_EXECUTABLE=/usr/local/bin/python3 -DPYTHON3_INCLUDE_DIR=/usr/local/Cellar/python3/3.4.2_1/Frameworks/Python.framework/Versions/3.4/include/python3.4m -DPYTHON3_LIBRARY=/usr/local/Cellar/python3/3.4.2_1/Frameworks/Python.framework/Versions/3.4/lib/libpython3.4.dylib -DPYTHON3_NUMPY_INCLUDE_DIRS=/usr/local/lib/python3.4/site-packages/numpy/core/include/ -DPYTHON3_PACKAGES_PATH=/usr/local/lib/python3.4/site-packages/ ..
make -j8
make install
python3 -c "import cv2; print(cv2.__version__)"
the last line tells me I'm now running 3.0.0-dev. According to this question, cv2.createBackgroundSubtractorGMG ought to be available in this version, however it's not; and indeed, it seems to have been moved to obsolete in opencv master.
Interestingly enough, in my own tests the current (3.0.0-dev) versions of createBackgroundSubtractorKNN and createBackgroundSubtractorMOG2 work much better than the ones I tested before (MOG and MOG2) in opencv2. So possibly the GMG algorithm got moved into those. Or, if not, why is the GMG version considered obsolete now? And how can I get the obsolete version to work (on python3), to compare the results?
I don't think it is obsolete... it was just moved to the contrib repository. You have to install it with OpenCV and then it is available under cv2.bgsegm. Follow the link for build instructions.
Related
It's been a long time since I last built opencv, contrib and all. The last installation I did, I recall being able to shrink the size of the installation after it was done; presently the file "build" is 28 gigabytes. My previous installation was able to be reduced in size to about 12 gigabytes after installation by removing files that are only necessary for installing and building, but not running. I have since forgotten what these files are that can be removed, and the installation tutorial that told me which ones were able to be removed. Can some shed some light on which files in my build folder can be removed after my release and debug builds have been installed?
If your intention is to extract the "bin/ include/ lib/ share/" QUAD and remove the entire cmake build tree, there is a simple thing you can do:
cd /path/to/cv/build
DESTDIR=/tmp/lalala make install -j7
Then you'll find what the QUAD in /tmp/lalala/path/to/your/original/install/dir. If that's all you need, rm -rf /path/to/cv/build.
If you are not using Linux/Unix & make however, let me know in the comment and I'll edit the answer.
Love your spiderman movies, btw. :-)
I revised some source code of OpenCV's legacy module. My project is coded based on the new legacy module and I want to debugging it. One way that I can think out is using my revised legacy source code to replace the original legacy module, then compile and reinstall the whole OpenCV. I think this way is too waste of time and other modules(e.g. imgproc, highgui, etc) haven't any change and don't need to be reinstalled. I think there must have an easier way to solve it.
My developing environment is VIM && GDB && opencv 2.4.13. I am a green-hand of linux-opencv. How do I build OpenCV's single module in Ubuntu? If I want keep the original legacy module and the new legacy module in case of other usage, how should I do?
There is a way to actually build a single module without building the entire source from the beginning. I guess you would have followed this procedures to install OpenCV in your machine OpenCV Installation in Linux.
After the modifications in OpenCV's legacy module, you can build just that module by using the commands.
# Go to the build directory. If you followed the tutorial I shared then it is the release folder
cd release
# And build only the module you want to (For example, legacy model as in your case)
make opencv_legacy
sudo make install
I have a Rails project that is going to be using OpenCV, and it depends on a certain version of it (2.4.6.1).
I'm looking for deployment advice. The Ubuntu opencv package is an earlier version and therefore not suitable.
I can see a number of possibilities, but I'm trying to think of what will work best.
Just write it up in a README and expect people to follow it: download this, apt-get that, etc...
Add opencv, tagged at the version we need, as a git subtree, and include a Rake task to build it.
Write a script to download and compile the needed code.
Something else ?
None of them seem all that great, to tell the truth.
Can your application be made to work with OpenCV 2.4.2? That is available in Ubuntu 13.04, and you could request it be backported to 12.04. If not, you could update the source package to 2.4.6.1 (which would require learning about debian packaging but might not be too difficult since you would be modifying an existing package instead of starting from scratch), upload it to a PPA, and instruct your users on Ubuntu to install OpenCV from there. You could also package your rails application and put it in the PPA, which would make overall installation even easier.
In attempting to install the latest ImageMagick (and devel) RPM from http://www.imagemagick.org/download/linux/CentOS/x86_64/ I receive this message
ImageMagick-libs = 6.8.5-8 is needed by ImageMagick-devel-6.8.5-8.x86_64
Confusingly, there is no ImageMagick-libs RPM listed, and searching has yet to yield a solution. Is there a way around this existential dependency?
Neither I nor Google know where ImageMagick-libs lives nor what it contains, but for posterity this gets things up and running on CentOS 5.8 (the distribution listed on imagemagick.org):
>: rpm -Uvh --nodeps ImageMagick-6.8.5-8.x86_64.rpm ImageMagick-devel-6.8.5-8.x86_64.rpm
>: ln -s /usr/include/ImageMagick-6 /usr/include/ImageMagick
The symbolic link was necessary for software relying on ImageMagick header files.
If someone were to stumble upon this, the ImageMagick-libs RPM are now downloadable from the link in the question.
I ran into the same thing when building the RPMs myself.
line 66 of the SRPM's included ImageMagick spec file includes:
Requires: %{name}-libs = %{version}-%{release}
I just commented out that line and the build completes; the resultant RPM satisfies the requirement cleaner. In sum, I believe it a bug in the SPEC file bundled in the SRPM. It isn't necessary for functionality even when building against php magickwand and similar finicky tools that require headers from ImageMagick.
What is the preferred method of exporting a homebrew environment so I can synchronize my workspace between computers? Seems like there should be something similar to composer.lock or pip freeze. Is there a better way than brew list > brews.txt?
There is a better way: brew leaves.
This command prints a simple list of installed formulae which are not dependencies of any other formulae. Essentially this lists everything that was manually installed or is a leftover dependency from a removed formula.
$ brew leaves
apple-gcc42
bash-completion
brew-cask
git
[...]
There's no built-in means of using brew leaves output to install, but just having a clean list of manually-installed formulae is a step in the right direction.
Thanks to this Gabe Berke-Williams for writing about this: http://robots.thoughtbot.com/brew-leaves
Homebrew Bundle seems like a pretty great solution.
There is not a better way, and there are no current plans to make one.
Source: https://github.com/mxcl/homebrew/issues/17771
Use git! Maintaining repos for environment setup scripts is a pretty slick approach.
I highly recommend using a script to set up a development environment in the first place. thoughtbot has a really lightweight approach that provisions a development environment, including a bunch of brew formulas. https://github.com/thoughtbot/laptop. GitHub just open sourced boxen for this (and much more), but it has a somewhat steeper learning curve.
As you can see from the thoughtbot/latop readme, the entire install is a one-liner. If you want different packages, fork the repo and add whatever you use. This only covers the initial install, but it is a fantastic start.
For ongoing synchronization of development environments, including updating your preferred homebrew setup, you might want to try a 'dotfiles' approach. Zach Holman has a great approach detailed here: https://github.com/holman/dotfiles
If you want to tweak or update anything, just make the appropriate changes to the script (holman's dot script does the ongoing update stuff). Commit, push, pull down from any other environments.