On Mon, 2016-04-04 at 13:31 +1000, Jim Birch wrote: > On 2 April 2016 at 13:54, Karl Auer wrote: > "compressed for transmission" means "has had much data discarded". > > All digital video is compressed, except maybe the truly lossless > "raw" digital masters at a studio. These chew up massive > bandwidth/storage, and, contain a lot more information than the human > eye can see. Forget it. There is actually no benefit to the end > viewer in using this stuff, it's a massive waste of resources.
Well, perhaps.That's why video "compression" works, much as mp3 does with hearing. Fact is though, that anyone who cannot hear the difference between even a 320Kbps MP3 and the original probably has a hearing problem. Depending on the device being used to view it, "compressed" video may be really great or really bad. I download iView programs and watch them in a corner of my monitor, and they look really good. I imagine they'd look great on a phone, too. But if I watch the exact same download on a big TV screen (or even just full-screen on my monitor), it looks very patchy. Real movie-quality photographic film runs at about 5000dpi; digitised, that's something like 19TB for a feature film. I don't know what resolution digital film has, but it must not be too dissimilar, because for display on a cinema screen, you need as much of it as you can get. You really don't need all that for a television or a phone. So I'm not knocking video "compression". But I do think people should know what they are paying for. > This is why Netflix look so great compared > to somecrappy youtube video: they might both have the same nominal > resolution and bit rate but Netflix really grind the best possible > result out of the bandwidth. Of course. My point was simply that people should understand that in the video world "compression" does not mean what a reasonable person might think it does. It means data has been discarded. Cleverly, selectively, but it's still discarded. > In this context "compressed for transmission" doesn't mean > compressed, every one does that. That doesn't entirely make sense... Regards, K. -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Karl Auer (ka...@biplane.com.au) http://www.biplane.com.au/kauer http://twitter.com/kauer389 GPG fingerprint: E00D 64ED 9C6A 8605 21E0 0ED0 EE64 2BEE CBCB C38B Old fingerprint: 3C41 82BE A9E7 99A1 B931 5AE7 7638 0147 2C3C 2AC4 _______________________________________________ Link mailing list Link@mailman.anu.edu.au http://mailman.anu.edu.au/mailman/listinfo/link