Fixed README

README.md

@@ -1,11 +1,30 @@
-libsdr - A simple software defined radio (SDR) library
-======
+# libsdr - A simple software defined radio (SDR) library
 
 **First of all:** I  assembled this library for my one entertainment and to learn something about software defined radio. If you are interested into a full-featured, performant SDR framework, consider using GNU radio (http://gnuradio.org). 
 
 
-License
-=======
+## Build
+
+The only required run-time dependency of `libsdr` is `libpthread`, which is available on all Unix-like OSs like Linux and MacOS X, it is also available for windows if `mingw` is used (http://www.mingw.org) of compilation. Additionally there are some optimal dependencies, which allow for the usage of some additional features of the library. 
+
+* `Qt5` (http://qt-project.org) - Enables the `libsdr-gui` library implementing some graphical user interface elements like a spectrum view.
+* `fftw3` (http://www.fftw.org) - Also required by the GUI library and allows for FFT-convolution filters.
+* `PortAudio` (http://www.portaudio.com) - Allows for sound-card input and output.
+* `librtlsdr` (http://rtlsdr.org) - Allows to interface RTL2382U based USB dongles.
+
+For the compilation of the library, `cmake` (http://www.cmake.org) is also required (as well as a compiler like gcc or clang of cause).
+
+Compiling the library is the canonical cmake path:
+
+```
+mkdir build
+cd build
+cmake .. -DCMAKE_BUILD_TYPE=RELEASE 
+make
+``` 
+
+
+## License
 
 libsdr - A simple software defined radio (SDR) library
 Copyright (C) 2014 Hannes Matuschek