Add image tuple support

[Evizero]

Motivation

The goal of having image tuple support is to support use cases such as image segmentation, where the input and the target are both images.

The interface should be as follows. Where one can currently write:

augment(X, mypipeline)

it should also be possible to write:

augment((X1,X2,X3), mypipeline)

These images should always traverse the same path through the pipeline, even if randomness is involved. As an example if one operation in mypipeline is an elastic distortion, then the distortion must be the same for each of the three images.

Todo list

So far i made some very basic refactors to get the current suite of tests to pass, while allowing for iterative adaption of the individual operations and their tests. Many of the simpler operations should already work, but still lack tests for the new behaviour; those are marked as "missing tests".

General

• augment
• augment!
• augmentbatch!
• update documentation
• update README.md maybe some other time
• update NEWS.md

Operations

• CacheImage
• CacheImageInto
• Either (most complex one)
• Rotate
• Scale
• ShearX
• ShearY
• Zoom

Missing Tests

• SplitChannels
• CombineChannels
• PermuteDims
• Reshape
• ConvertEltype
• Crop
• CropNative
• CropSize
• CropRatio
• RCropRatio
• ElasticDistortion
• FlipX
• FlipY
• MapFun
• AggregateThenMapFun
• NoOp
• Resize
• Rotate90
• Rotate180
• Rotate270