here we have what it takes to mex three cxx routines (NN demosaicing, ZhangWu demosaicing and LSD)
Other than readme and mexall, all the files are in the directory *modif*

* appl.cpp: modified demosaick() which reads in a float array instead of the file name
* appl.hpp: modified header/interface
* nn_mex.cpp: matlab interface for demosaick()
* io_png.c: explicit type conversion to prevent g++ from complaining about void*
* zw_mex.c: matlab interface for zhangwu()
* lsd_mex.c: matlab interface for LSD()
* makefile.zw: makefile for zw_mex
* makefile.nn: makefile for nn_mex
* makefile.lsd: makefile for lsd_mex
* test.m: a test matlab script
* makefile: it does all the rest

* instructions *

make mex first. Then start matlab and run test.m
code tested under Ubuntu 14
The demo only handles the RGGB Bayer pattern.
