Rotate image without losing information

gist.github.com

1 pointriyadparvez5 comments

> Rotate image without losing information ...

Actually, lossless rotation is only possible for 90/180/270 degrees, otherwise some information loss is unavoidable.

No it preserves information by not losing any pixel, instead it pad extra pixel

Fine. Rotate an image to an angle that's not a multiple of 90 degrees and that is the same size, then rotate it back. Compare the old and new. They will not be the same, because of lost information.

I can't believe you don't know this -- rotating bitmap images at angles other than multiples of 90 degrees always loses information.

Oh, yes. That's true. I thought you are talking about losing pixel.

But loss of information and loss of pixel content are the same thing. If you have an image with dimensions of, say, 1000 x 1000 pixels, and you rotate it other than a multiple of 90 degrees, you will lose much of the original pixel content. It's unavoidable.

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