http://www.researchgate.net/post/Which_is_the_best_opencv_or_matlab_for_image_processing
Annette Morales-González · Centro de Aplicaciones de Tecnologias de Avanzada
It depends on your purpose:
Matlab --> Faster programming, less efficient
OpenCV -->Slower programming, more efficient
I have used both for a long time and I switch from one to the other depending on what I‘m doing. If you‘re doing research (for instance, if you‘re testing different algorithms, different representations, etc) I recommend Matlab, since you will be able to program faster. If you already had a result of your research, and wan‘t to make an application with it, I recommend OpenCV, it will take longer to program, but you can make more time and memory optimizations. If you are doing research but you‘re working with very large datasets, features, etc, maybe you‘ll have to use OpenCV instead of Matlab in order to play with memory optimization, since with large data Matlab tends to crash frequently. According to the image processing functionalities they provide, I think both are well equipped, but I would say that Matlab is better in this case, and you can find more Matlab source code in internet than OpenCV‘s.
Carles Fernández · Herta Security
In the past I have worked extensively with both Matlab and OpenCV.
Matlab allows you to prototype faster, for instance in order to test a method, compare the accuracy of different techniques, estimate which implementation runs faster, or learn the best parameters for a model. It is especially interesting for fast debugging and fast visual plotting of results, in particular for research in image processing. It is also fairly easy to find public source code shared by users.
OpenCV allows you to efficiently encode algorithms for computer vision. It will run much faster than Matlab code, but it will take longer to implement and to debug. You will be able to incorporate external libraries, and is a great help for serious solution coding. There are several tutorials and nice documentation out there, and it is well maintained.
Unlike some users have suggested above, I completely discourage to use any utilities that convert Matlab to C/C++, nor to port any OpenCV functions to Matlab. That makes little sense. Your code will be more efficient by carefully coding it from scratch using the proper libraries, and most times you will go faster by implementing something from scratch in Matlab over some base code. Both Matlab and OpenCV contain a great deal of image processing utilities, from basic to advanced requirements, so they are mostly interchangeable depending on your goal.