

GitHub New Features: Rendering and diffing images - sunilkumarc
https://help.github.com/articles/rendering-and-diffing-images

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voltagex_
Simple (UI wise, I'm sure the implementation is tricky), yet very useful.

I wonder if there's a way to represent changes that might not be easily seen -
say you ran an image through pngcrush.

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sunilkumarc
"The main purpose of pngcrush is to reduce the size of the PNG IDAT datastream
by trying various combinations of compression methods and delta filters." \-
Wikipedia.

So there will not be any change in the image visually. The 'crushed' image
will have the same quality as the source image. So even if you run an image
through pngcrush, this new github feature should not find any difference
between the original image and the 'cushed' one(I think).

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cleverjake
1\. This isn't a new feature, its existed for years. 2\. Git detects a
difference, so github will detect a difference.

That being said, there wouldn't be a visible difference when comparing the two
images.

~~~
sunilkumarc
So, what kind of change will the git detect when an image is crushed (when
there is no visual difference between original and curshed) ?

~~~
michaelmior
As far as git is concerned, the PNG file is just a bag of bits. It will record
the changes in the IDAT chunks just as with changes in any other files. The
images would appear identical on GitHub because they haven't changed visually.

