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Comment by zbobet2012 | Hacker News Reader

zbobet2012·

The best answer to this question is actually provided by Ouss which is only at 1 up vote. Showing the 1d case for frequency of an image is far more illuminating than showing the 2d case.

Most people with a mathematics, or music background of any level understand frequency in terms "hertz". Aka speed of vibration. Translating it to speed of change of pixel value per pixels is difficult without the 1d case.

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Yeah, I don't know. Ouss' answer doesn't quite spell out what the repeating event is in the context of the image. He shows a formula that calculates pixel intensities with an "f" cosntant, but doesn't explain what that "f" is and what it does to the pixel intensities. I mean, it's so easy to say "frequency in an image is the rate of change of pixel intensity".

Sometimes when someone asks a question about something simple you have to just spell it out as simple as possible.

(Another thing that works for me given a 2d image like Ouss' example is "think of looking at a sine wave from above" much as this makes no real sense).

Yes, I really liked this, because it was well structured and has the style I understand best.

What was interesting to me, was the irritating effect the high frequency image has to my eyes. It's like I need to move my eyes very fast when I look at that picture.

> The best answer to this question is actually provided by Ouss

Could you share a direct link? I don't see any such comment here.

It was the second post by the time I got there, but the rankings are fluid so here's a permalink: https://photo.stackexchange.com/a/112702

https://photo.stackexchange.com/a/112702

Yeah, got me too. Ouss is actually a respondent in the linked StackOverflow article.

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