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As usual the article misrepresents video compression. Almost l useful coding tools are spatial and not frequency based; the only famous one (DCT) was replaced with a rough approximation in H.264 and it works just as well.

This is because lots of realistic images don't really have meaningful frequency-based content. (imagine sampling every 8 or 16 pixels - would their values be in any way related to each other?)




Don't think of them in terms the full function. You can approximate a strait line by a small part of a long sine wave. http://www.wolframalpha.com/input/?i=Sin%28x%29++from+.01+to...

But, for a real world example look at jpeg.

Next, each 8×8 block of each component (Y, Cb, Cr) is converted to a frequency-___domain representation, using a normalized, two-dimensional type-II discrete cosine transform (DCT). http://en.wikipedia.org/wiki/JPEG




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