Remove imgaug dependency

[danifranco]

imgaug project is not being updated. We should implement the transformations used through imgaug to remove its dependecy completely. The transformations are these:

• Rotation 90 #63
• Random rotation
• Shear
• Zoom
• Shift
• Vertical flip
• Horizontal flip
• Elastic transformation
• Gaussian blur
• Median blur
• Motion blur
• Gamma contrast
• Notebook presenting all transformations

Also because we adapted 3D images to use them as 2D images for imgaug, which gives weird messages everytime a transformation is used:

/home/dfranco/anaconda3/envs/BiaPy_env/lib/python3.8/site-packages/imgaug/augmenters/base.py:49: SuspiciousSingleImageShapeWarning: You provided a numpy array of shape (160, 160, 40) as a single-image augmentation input, which was interpreted as (H, W, C). The last dimension however has a size of >=32, which indicates that you provided a multi-image array with shape (N, H, W) instead. If that is the case, you should use e.g. augmenter(imageS=<your input>) or augment_imageS(<your input>). Otherwise your multi-image input will be interpreted as a single image during augmentation.

[pr4deepr]

What about something like albumentations??
I came across this project that uses albumentations but uses it in 3D:
https://github.com/ashawkey/volumentations

It uses scikit image transforms under the hood and also considers interpolations

[danifranco]

Indeed, that library is commendable, however, we aim to minimise our dependence on external projects as much as possible.

[pr4deepr]

Fair point.