What does the "-compare" option do?

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XnTriq
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What does the "-compare" option do?

Post by XnTriq »

nconvert.exe -help wrote:

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-compare filename method : Compare with this image, method (red, red_only)
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xnview
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Re: What does the "-compare" option do?

Post by xnview »

output pixels difference between 2 images (need to be same size)
Pierre.
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XnTriq
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Re: What does the "-compare" option do?

Post by XnTriq »

xnview wrote: Wed Feb 03, 2021 7:09 amoutput pixels difference between 2 images (need to be same size)
:-D I was hoping for something like this to be implemented, but I can't get it to work.

How do I tell nConvert to compare (the blue channels of) two images (original.png + edited.png)?

Code: Select all

nconvert.exe -compare edited.png original.png
Could you please give me an example illustrating the purpose of the method argument and what values (red/green/bue? red_only/green_only/blue_only/alpha_only?) are accepted as parameters?
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Re: What does the "-compare" option do?

Post by xnview »

you can try

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nconvert.exe -compare edited.png red original.png
only red/red_only as parameters
Pierre.
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XnTriq
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Re: What does the "-compare" option do?

Post by XnTriq »

xnview wrote: Wed Feb 03, 2021 10:39 amyou can try

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nconvert.exe -compare edited.png red original.png
only red/red_only as parameters
Thanks, Pierre!

test.png
test.jpg
nconvert_red.png
nconvert_redonly.png
imagediff.png
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