file structure of NoiseAPI is available at:
https://github.com/johnnychen94/ImageNoise.jl/tree/8934d6333d471857fef82af8b3a85cace1b87d47/src/NoiseAPI

* replace `BinarizationAlgorithm` with `AbstractImageBinarizationAlgorithm`
* import `binarize` and `binarize!` from `BinarizationAPI`
* move concrete algorithms struct definitions to seperated files

This is a intermediate commit as a start point for the following code refactor, i.e.,
moving implementations to concrete functors

…age dependency

* move implementations to AdaptiveThreshold functor

* Rewrite AdaptiveThreshold with CartesianIndices to support n-D images

* update and simplify the docstring

* enhance the test codes and fix several bugs

* add CartetianIndex compat to Julia 1.0

* deprecate `window_size` and `recommend_size`

This is a PR-commit for PR
#29
that refactors the whole codebase to use the new functor API, which
is discussed in more details in
#26
and explained in my GSoC 2019 blog
https://nextjournal.com/johnnychen94/the-principles-of-imagesjl-part-i

Changes:

* move implementations into functor
* enhance the test codes with wider test coverage

This is a PR-commit for PR
#29 that
refactors the whole codebase to use the new functor API, which
is discussed in more details in
#26 and
explained in my [GSoC 2019
blog](https://nextjournal.com/johnnychen94/the-principles-of-imagesjl-part-i)

Changes:

* support `Color3` input
* move implementations into functor
* enhance the test codes with wider test coverage

This is a PR-commit for PR
#29 that
refactors the whole codebase to use the new functor API, which
is discussed in more details in
#26 and
explained in my [GSoC 2019
blog](https://nextjournal.com/johnnychen94/the-principles-of-imagesjl-part-i)

Changes:

* support `Color3` input
* move implementations into functor
* enhance the test codes with wider test coverage

This is a PR-commit for PR
#29 that
refactors the whole codebase to use the new functor API, which is
discussed in more details in
#26 and
explained in my [GSoC 2019
blog](https://nextjournal.com/johnnychen94/the-principles-of-imagesjl-part-i)

Changes:

* support `Color3` input
* move implementations into functor
* enhance the test codes with wider test coverage

This is a PR-commit for PR
#29 that
refactors the whole codebase to use the new functor API, which is
discussed in more details in
#26 and
explained in my [GSoC 2019
blog](https://nextjournal.com/johnnychen94/the-principles-of-imagesjl-part-i)

Changes:

* support `Color3` input
* move implementations into functor
* enhance the test codes with wider test coverage

This is a PR-commit for PR
#29 that
refactors the whole codebase to use the new functor API, which is
discussed in more details in
#26 and
explained in my [GSoC 2019
blog](https://nextjournal.com/johnnychen94/the-principles-of-imagesjl-part-i)

Changes:

* support `Color3` input
* move implementations into functor
* enhance the test codes with wider test coverage

This is a PR-commit for PR
#29 that
refactors the whole codebase to use the new functor API, which is
discussed in more details in
#26 and
explained in my [GSoC 2019
blog](https://nextjournal.com/johnnychen94/the-principles-of-imagesjl-part-i)

Changes:

* support `Color3` input
* move implementations into functor
* enhance the test codes with wider test coverage

This is a PR-commit for PR
#29 that
refactors the whole codebase to use the new functor API, which is
discussed in more details in
#26 and
explained in my [GSoC 2019
blog](https://nextjournal.com/johnnychen94/the-principles-of-imagesjl-part-i)

Changes:

* support `Color3` input
* move implementations into functor
* enhance the test codes with wider test coverage

This is a PR-commit for PR
#29 that
refactors the whole codebase to use the new functor API, which
is discussed in more details in
#26 and
explained in my [GSoC 2019
blog](https://nextjournal.com/johnnychen94/the-principles-of-imagesjl-part-i)

Changes:

* support `Color3` input
* move implementations into functor
* enhance the test codes with wider test coverage

Refactor Yen using the functor API

Refactor Otsu using the functor API

Refactor Moments using the functor API

Refactor MinimumIntermodes using functor API

Refactor Entropy using the functor API

refactor UnimodalRosin using the functor API

refactor Intermodes using the functor API

refactor Balanced using the functor API

refactor MinimumError using functor API

Otherwise it would return `nothing`

* AdaptiveThreshold: infer the window_size from img during construction

* Niblack: revert the deprecation on window_size