[TorKlingberg]

Others have noted you got the CD-R speeds wrong, but sometimes sending is indeed easier than receiving. I used to work on radio signal processing for phones, and we'd spend far more of both DSP cycles and engineering effort on the receive side. Transmission is basically just implementing a standardized algorithm, but on the receive side you can do all kinds of clever things to extract signal from the noise and distortions.

Video codecs like h264 or VP9 are the opposite: Decoding is just following an algorithm, but an encoder can save bits by spending more effort searching for patterns in the data.

[kqr]

> Video codecs like h264 or VP9 are the opposite: Decoding is just following an algorithm, but an encoder can save bits by spending more effort searching for patterns in the data.

This is a more general point about the duality of compact encoding (compressing data to the lowest number of bits e.g. for storage) and redundant encoding (expanding data to allow error detection when transmitted across a noisy medium.)