[anticristi]

This. I'm not even sure why anyone would bother ELI5-ing the DCT with images. Here is an attempt to explain the DCT using audio:

The DCT converts music into key presses on a piano. When playing back those keys on the piano, you lose the text of the music, but you sure hear the melody.

There! Way more ELI5-ish.

[ponderingfish]

huh? if you throw away 70% of the melody, do you get back the text? If not, you haven't explained the DCT.

[Jasper_]

In this analogy, you are throwing away the instrumentation, like whether it was played on a piano or a tuba, but the raw melody is still there.

This is the advantage of working in the frequency space. If we were in the time space, throwing away 70% of the data would throw away 70% of the melody.

[ponderingfish]

And a 5 year old understands instrumentation, melody, piano, and the tuba?

[anticristi]

In my ELI5 analogy, the DCT "throws away" the voice. You can still recognize the song.