F9 Corner Detection Library is an open source implementation of the FAST-9 corner detection algorithm, which avoids many re-allocations and tries to generally perform better.
Note: This code is pretty old, and only kept for reference. A more modern approach would probably involve using the GPU instead of doing everything on the CPU.
The library consists of a single source file (f9.cpp) and a public header file (f9.h), and can be packaged as a static or shared library as well as built directly into your projects.
Update Feb, 1st 2017: @jwijffels created an R package around this code, which you can find at https://github.com/bnosac/image.CornerDetectionF9
See f9.h.
Multithread support: The F9 context (C API) and the F9 class (C++ API) are not thread-safe, but it's easy to create one of these for each thread where you need to perform corner detection (the library is reentrant). You could for instance split a big image in four tiles and detect its corners in four threads, using four F9 contexts/instances in total.
This code is released under the terms of the Simplified BSD License below.
Copyright 2011 Julien Cayzac. All rights reserved.
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