Adds deprecations for adjust_histogram(img, LinearStretching()) variants

[zygmuntszpak]

No description provided.

[codecov]

Codecov Report

Merging #51 (77c3b48) into adjust_intensity (42795dd) will increase coverage by 0.02%.
The diff coverage is 29.41%.

@@                 Coverage Diff                  @@
##           adjust_intensity      #51      +/-   ##
====================================================
+ Coverage             92.12%   92.15%   +0.02%     
====================================================
  Files                    13       14       +1     
  Lines                   597      612      +15     
====================================================
+ Hits                    550      564      +14     
- Misses                   47       48       +1     

Impacted Files	Coverage Δ
src/algorithms/linear_stretching.jl	95.00% <ø> (ø)
src/deprecations.jl	29.41% <29.41%> (ø)
src/ContrastAdjustmentAPI/intensity_adjustment.jl	42.85% <0.00%> (+42.85%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 42795dd...77c3b48. Read the comment docs.

[johnnychen94]

For these I think we can simplify it with

Suggested change

	function adjust_histogram(img::Union{GenericGrayImage, AbstractArray{<:Color3}},
	f::LinearStretching,
	args...; kwargs...)
	depwarn("adjust_histogram(img, LinearStretching()) is deprecated, use adjust_intensity(img, LinearStretching()) instead", :adjust_histogram)
	return adjust_intensity(img, f, args...;kwargs...)
	end
	@deprecate adjust_histogram(img::AbstractArray, f::LinearStretching, args...; kwargs...) adjust_intensity(img, f, args...; kwargs...)

[zygmuntszpak]

It turns out that writing the longer variant is useful because I can then unify all the deprecation messages for the 3 types that need to change (LinearStretching, GammaCorrection and ContrastStretching) into one as follows:

function adjust_histogram!(img::Union{GenericGrayImage, AbstractArray{<:Color3}},
                           f::Union{LinearStretching, GammaCorrection, ContrastStretching},
                           args...; kwargs...)
    algo = typeof(f)
    depwarn("adjust_histogram!(img, $algo) is deprecated, use adjust_intensity!(img, $algo) instead", :adjust_histogram!)                       
    return adjust_intensity!(img, f, args...; kwargs...)                          
end

That should save us from a bunch of code duplication. What do you think?

[johnnychen94]

It's just that in this case we don't need to manually construct the depwarn message info:

const DeprecatedIntensityMethods = Union{LinearStretching, GammaCorrection, ContrastStretching}
@deprecate adjust_histogram(img::AbstractArray, f::DeprecatedIntensityMethods, args...; kwargs...) adjust_intensity(img, f, args...; kwargs...)

[timholy]

Is there any reason not to do a wholesale rename adjust_histogram -> adjust_intensity? Don't all of our adjustment methods operate solely on the intensity? For RGB we convert to YIQ and then adjust just Y, so that too modifies only the intensity: the term adjust_histogram is a bit ambiguous about how we handle RGB (it leaves open the possibility that we operate channelwise), but the term adjust_intensity is quite clear.

It would be wrong if we did something other than modifying the pixelwise intensity, so if there are such places then please do bring them up.

[zygmuntszpak]

I'm OK with renaming it all as adjust_intensity as well. Is there a case to be made for adjust_intensities ?

[timholy]

That sounds fine too, and perhaps even better.