Deep, Multiple channels, Variable Bit Depths and Metadata support

[sosoyan]

Currently I need to write a tool like this, but with support of deep, multiple channels, variable bit depths and combined Metadata. I was wondering if you are working on any of these features, so we don't do the same thing?

[MrMabulous]

multi channel (in particular swizzling similar to shader languages use it) and variable bit depths yes, but metadata and deep not yet. But I'd be happy to pull your changes if you create any pull requests