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Video encoding requires using your eyes

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Re: Video encoding requires using your eyes

#51

Earlier quoted context omitted.

End users aren't domain experts. That's like if I was allowed on the factory floor where my favorite products are made so that I could make subjective, uninformed decisions about the manufacturing process which also affect everyone else.

Is it? Or is it like if you were allowed into a focus group where they let you try out two manufactured products, so that you could make subjective, uninformed decisions about the product lineup which also affect everyone else?

Laundering manufactured consent for cheaper, inferior products as consumer choice is a pretty old trick.

A consumer's perceived preference can be modulated by any number of issues with which the consumer is not properly informed, such as preferring one sweetener over the other, even if there are valid health concerns, thanks to generational brainwashing and an intentional lack of consumer training. What we have today is the consumer market equivalent to the unsophisticated investor market. People getting economically exploited and feeling like it was their own idea.

In the case of video encoders... Actual domain experts should not be forced to cede to the whim of an untrained eye simply for the purpose of capitalists extracting more money from them.

It's one thing for Netflix to experiment with the latest advances in machine learning, as a lot of us do. But when the opening sentence is to their blog is "When you are binge-watching the latest season of Stranger Things or Ozark, we strive to deliver the best possible video quality to your eyes", it's hard not to find issue with A) the commodification of entertainment and patronizing consumer speak and B) a misleading preposition about commitment to quality which the cited response article makes clear is untrue in the case of this product.

Deferring to domain experts in this case is better for every consumer, as they will not be duped into exchanging an increasingly degraded experience in exchange for increasing monthly rates. People feel very strongly about film quality, and for good reason. We're talking about the preservation of art and culture, but Netflix doesn't see it this way, as to them, it's all a commodity, and they manufacture consent for commodification. If the average user can't see this and push back against the degradation of quality that comes with commodification of art, I have a hard time deferring to them over an actual expert.

Re: Video encoding requires using your eyes

#52
post #49

Earlier quoted context omitted.

It doesn't come from "oversharpening".

Sharpening and bandwidth-limiting have the exact same effect, because the maximum sharpness of an image (like any other signal) depends on its bandwidth. There is no difference in the type of artifact produced. That's why the artifact from both has the same name of "ringing".

It doesn't come from "sharpening" at all though. That implies an increase in frequencies. This compression artifact comes from rounding them, so they're moved in both directions.

Re: Video encoding requires using your eyes

#53
post #43

Earlier quoted context omitted.

That is what it should mean, but in image compression people use it to mean "mosquito noise" artifacts, which come from quantizing DCT compression applied to edges. (Nyquist theorem = DCT is bad at edges because they're made of an infinite number of frequencies.)

That is the exact same phenomenon. Artificial sharpening is introducing high bandwidth components to a signal. If you bandwidth limit (low pass) a signal to fit below the Shannon-Nyquist limit you will get ringing as the signal cannot be represented accurately and will smear in the time domain. Given a bandwidth constraint, artificial sharpening above a certain threshold will result in ringing.

Images don't have infinite bandwidth, so that doesn't apply. The filter used in H264 and newer codecs is exact and nearly reversible, there aren't artifacts from applying it. The artifacts come from the rounding afterward.
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