How to generate the original image from feature set? We all know that using CNN, or even simpler functions, like CLD or EHD, we can generate a set of features out of images. 

Is there any ways or approaches that given a set of features, we can somehow generate a corase version of the original image that was given as input? Maybe a gray-scale version with visible objects inside? If so, what features do we need?
The model (that I know of) which most resembles your description is the auto-encoder, which is trained to learn a compact representation (a vector) of the input, which can later be used to reconstruct the original input. In a certain way, this compact representation (implicitly) encodes the most important features of the input. In particular, you may be looking for denoising auto-encoders.