Python and lua both have good frameworks for developing such models (tensorflow, theano possibly with lasagne or keras, torch, caffe...).

The visual part need access to efficient GPU-based implementation of convolutions (typically using cuDNN from nvidia or neon from Nervana Systems).

You could write bindings for other languages or even work directly in C++ but I think that an interactive programming language with a REPL like Python and lua is very helpful for faster iterative model building, interactive exploration and evaluation.