MATLAB is a multi dimensional programming platform and a fouth generation programming language. It allows matrix manipulations,algorithm implementation through graphs,plots and with other laguages like C,C++,Java.
There are various toolboxes for every engineering stream like aerospace,electrical, computer science etc. Using these toolboxes you can create your models and codes as per problem statement.
You can also use Simulink, which is a block representation of the programs and assemble them to avoid heavy coding. 
To make your program user defined , you can use Graphical User Interface feature in MATLAB
Digital Image Processing is a powerful toolbox in MATLAB and gives an upper edge to engineering students in getting better jobs in the market.
With Digital Image processing you directly work on the pixel of the image,change its structure and there by help building image filters to recover dilated images and also extract data from the image.