MPEG-2 Decoding Questions

[lordsmurf]

It's better to be clear than ambiguous.

Video jargon has always been big on ambiguity.

(I would these days)

That's sort of my point here. The goal posts often move with terms, to suit whatever party is saying it (normally corporations, not us peon users). I remember when "lossless" wasn't even a term in video, and have seen it mutate over the years.

"Visually lossless" originally implied one thing, but today who knows what it means. "Visually lossless" is a subjective, ambiguous , non quantifiable term, that can mean very different things to different people (people have different perceptions) - Someone with significant video and film experience will likely be able to see visual loss more easily than some random guy with zero video/film experience. There is a vast range of quality that people might truthfully call "visually lossless". "visually lossless" shouldn't be used at all for those reasons . I suspect the origins of the term "visually lossless" was Apple's Marketing Team .

Yep. But I think the term pre-dates Apple use, as they were really late to the video party.

In contrast, "Mathematically lossless" is a precise unambiguous term

Math can be equally ambiguous, but for reasons I can't easily explain (at least without my brain partially melting). What you have to remember is that math is also art, not pure science. You can use math as a cudgel, in very propagandist ways. Just remember "lies, damned lies, and statistics". There is a lot of ambiguity in math, especially when for-profit or for-ego motive is involved (and that's precisely what we have here, ie MPEG-LA, Apple, et al).

It's been many years, decades, since I saw a white paper discussing how Huffman (ie, Huffyuv) was not actually a lossless compression. I just searched Google for "huffman compression rounding errors", and Gemini gave this:

In Huffman compression, "rounding errors" can occur when calculating the frequencies of characters in the input data, particularly when dealing with floating-point arithmetic, which can lead to slight discrepancies in the resulting Huffman tree and potentially affect the compression ratio, although the decoded data should still be identical to the original due to the lossless nature of Huffman coding.

There's a lot more to it, and I probably saved it to my research years ago (either in cold archive storage, or printed papers in a file cabinet).

I don't see that we're far apart here. I'm just rejecting the rigid dogmatic aspects.

I think we're getting too OT anyway, too academic, so I bow out.

Whether "lossless" or "mathematically lossless" or "visually lossless", the goal is simply highest quality video. Not DVD-Video, not Youtube, etc.

[lollo]

It's been many years, decades, since I saw a white paper discussing how Huffman (ie, Huffyuv) was not actually a lossless compression. I just searched Google for "huffman compression rounding errors", and Gemini gave this:

In Huffman compression, "rounding errors" can occur when calculating the frequencies of characters in the input data, particularly when dealing with floating-point arithmetic, which can lead to slight discrepancies in the resulting Huffman tree and potentially affect the compression ratio, although the decoded data should still be identical to the original due to the lossless nature of Huffman coding.

Did you realize that what you wrote says the opposite of your thesis?
"rounding errors ... potentially affect the compression ratio, although the decoded data should still be identical to the original due to the lossless nature..."

I think we're getting too OT anyway, too academic, so I bow out.

Yes, you should.

What you have to remember is that math is also art, not pure science.

Not in the sense of altering reality to your liking!

[lordsmurf]

although the decoded data should still be identical to the original due to the lossless nature of Huffman coding.

Did you realize that what you wrote says the opposite of your thesis?

Read it again. "should" isn't "will". There are a lot of assumptions made, and can be argued. In fact, others have argued it, successfully, going back decades now.

What you have to remember is that math is also art, not pure science.

Not in the sense of altering reality to your liking!

Math is very esoteric, which is why you have things like number base systems that define the worldview of the math used within it. It's not art, as in a Picasso painting. But it's also not science, even if science uses math. (From a reasoning stance, science would all be bunk if math was science, because then science would be using more science to prove itself, ie circle jerking "logic".)

They make some excellent points here:
https://www.reddit.com/r/math/comments/qfvimy/is_math_an_art_or_a_science_or_neither/

I really wish you would just stop responding to my posts. All you want to do is argue and mock, never have a mature discussion. You're turning in a VH troll. Are you okay? You used to be a friendly person.

[lollo]

Read it again. "should" isn't "will". There are a lot of assumptions made, and can be argued. In fact, others have argued it, successfully, going back decades now.

I can read any time you want, but you are wrong. Period. No need to discuss any further. (lossless is lossless)

Math is very esoteric, which is why you have things like number base systems that define the worldview of the math used within it. It's not art, as in a Picasso painting. But it's also not science, even if science uses math. (From a reasoning stance, science would all be bunk if math was science, because then science would be using more science to prove itself, ie circle jerking "logic".)

They make some excellent points here:
https://www.reddit.com/r/math/comments/qfvimy/is_math_an_art_or_a_science_or_neither/

I won't read ravings about math being art. It is just a full bullshit, not deserving any loss of time.

I really wish you would just stop responding to my posts. All you want to do is argue and mock, never have a mature discussion. You're turning in a VH troll. Are you okay? You used to be a friendly person.

I am fine, thanks. I do not respond to you personally, I reply to idiocies every time I read them. Whoever writes them, and still being a friendly person

[dellsam34]

Generally speaking and I'm not addressing any particular member here, Personal confrontations are not a way of exchanging ideas or helping others, One can make his point politely and move on, the person/persons needing help will get the idea no matter what, and they can make their decision based on the facts laid down not the winning argument, just my 2 cents.