A Blu-ray is absolutely compressed. There is no way to get raw video unless you’re shooting it yourself.
Comment on Why hasn't video quality improved much over the past ten years?
infinitevalence@discuss.online 2 days ago
Compression. While Compression tech HAS improved, its been maintaining our current quality while reducing bandwidth needs.
A 1080p Bluray disk will look far far better than Netflix in 4k every time because its not compressed. The reality is that any form of compression will cause loss in fidelity in some way, so the only way to really improve video is to increase the bandwidth of the video.
I talk to IT nerds frequently who are asking things like “why do you need 16x 400GB ports of non blocking bandwidth” to which I have to explain that a SINGLE stream of uncompressed UHD is 12GB/s and we are trying to put 200+ streams onto their network.
deranger@sh.itjust.works 2 days ago
LainTrain@lemmy.dbzer0.com 2 days ago
Why not download? Streaming is always going to be dogshit quality unless we find something faster than light.
infinitevalence@discuss.online 2 days ago
Not all content can be downloaded, and for many people they want to watch what they want to watch right now, and waiting for the download is not something they are interested in.
Also rights holders dont want you to have an offline copy if they can avoid it, that way its easier to monetize for them.
LainTrain@lemmy.dbzer0.com 2 days ago
Also rights holders dont want you to have an offline copy if they can avoid it, that way its easier to monetize for them.
Well ain’t that a shame. I’ll weep for them I swear.
Not all content can be downloaded,
Like livestreams? That being the exception but most ‘content’ isn’t live.
and for many people they want to watch what they want to watch right now, and waiting for the download is not something they are interested in.
Bet they use YouTube through the home page and use algorithmic feeds and/or corporate social media. Some people are animals and it can’t be helped. That doesn’t mean the rest of us must suffer.
infinitevalence@discuss.online 2 days ago
Like livestreams? That being the exception but most ‘content’ isn’t live.
A shocking amount of content is live, and then encoded for streaming. Given that you are on Lemmy I would guess that your interests dont overlap much with content that requires live transmission. So this is an expected selection bias, not being critical, and totally not judging, just pointing it out so you can be aware. I bet your parents still have cable.
tatterdemalion@programming.dev 1 day ago
You mean 12 Gbps right?
infinitevalence@discuss.online 1 day ago
The standard is defined as 12000Mbits/s and spelled out as 12G-SDI or 12G SMPTE 2110.
So i do tend to mix things up since big G and little G mean different things in computer land.
JackbyDev@programming.dev 1 day ago
Is that “real” uncompressed or using a lossless compression? Or are uncompressed video streams inherently losslessly compressed because they only show changes, not sending a full image every frame?
infinitevalence@discuss.online 1 day ago
Ok, since were (as a group not you specifically) are getting pedantic, I should clarify that any recording of video is inherently compressed. There is no way to capture 100% of an image ever. There is optical compression created by the lenses, then their is encoding compression created by the Analog to Digital conversion, or if capturing in analog there is physical medium compression. Film has grain size and quality which limits it resolution, analog tape is limited by the speed, width, and magnetic medium density.
So for the sake of this larger discussion Uncompressed should probably refer to the point at which the content is being captured to a medium regardless of what that medium is.
Now in the context of broadcast and professional video production Uncompressed means specifically that the transport and capture of the content is dont done with the removal of any part of the data. Now even that is a little misleading because the sensors on most professional cameras can capture higher data rates than 12G, but the transport specification only allows for 12G we have to use chroma sub-sampling to go from 444 to 422 when we put the content onto the wire.
So all that said, when I talk about Uncompressed UHD video requiring 12G I mean that no codec is applied, and no frames are dropped. We are running at the maximum specified bandwidth of our link which is 12G UHD video at 59.94 frames per second. Every pixel is written every frame regardless of if its a camera pointed at a wall watching paint dry or not.
So, last thing on Lossless compression, as a professional I frequently take issue with codecs that claim lossless quality because frequently I can see the difference between the vast majority of compressed formats vs uncompressed formats. Sometimes instantly, sometimes it takes a few min before I see the compression. Lossless compression generally is one of theos 9 out of 10 doctors things were the majority of people say they cant see a difference therefor they can claim its “lossless.” I can frequently see the difference between 444 and 422 chroma subsampling, and that is not even considered compression. I am one of the annoying people who walks into a bar and asks why all the HD tvs are set to “fill” on an SD channel.
AnAmericanPotato@programming.dev 2 days ago
Yep. On a Blu-ray disk, you have 25-100GB of space to work with. The Blu-ray standard allows up to 40mbps for 1080p video (not counting audio). Way more for 4K.
Netflix recommends a 5mbps internet connection for 1080p, and 15mbps for 4K. Reportedly they cut down their 4K streams to 8mbps last year, though I haven’t confirmed. That’s a fraction of what Blu-ray uses for 1080p, never mind 4K.
I have some 4K/UHD Blu-rays, and for comparison they’re about 80mbps for video.
They use similar codecs, too, so the bitrates are fairly comparable. UHD Blu-rays use H.265, which is still a good video codec. Some streaming sites use AV1 (at least on some supported devices) now, which is a bit more efficient, but nowhere near enough to close that kind of gap in bitrate.