Comment by pwthornton | Hacker News Reader

Comment by pwthornton | Hacker News Reader

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This technology could be used to cut down on files sizes, to raise video quality and to up resolution. A few thoughts:

1. 1080p streaming video from Apple, Netflix and others looks pretty good, but it suffers from more compression artifacts when compared to Blu-ray. It simply doesn't look as good. With a more efficient compression technology, streaming video could have similar file sizes to today's H.264 video but look more like Blu-ray.

2. I already own a laptop that does above 1080p video. When Apple release a Retina iMac or Thunderbolt display it will be around 5k. Other manufactures will be there too. 4k or so TVs and projectors are on their way. Streaming technology makes a lot more sense than a new physical format for higher resolution video. In order to realistically deliver 4k video (or 5k video like The Hobbit is being shot in) over IP, we would need better compression than H.264

3. Files sizes could be cut down, allowing people to consume more video without going over their caps. This would also allow mobile devices to store more high quality video content for on the go.

The best case scenario would be that we get a combo of all three. 4k-5k video content is still a bit way for home use, but when it does come. H.265 sounds like the way to go.

In the next few years, this technology could be used to cut down on file sizes some, while also upping the quality of video. This is what we saw with Apple's 1080p video which uses high profile H.264 video, whereas Apple's 720p video is main profile H.264. Yes, the 1080p videos are bigger, but not by much.

Nitpick, but Thunderbolt supports a maximum of 20Gbits/sec which can't drive 5k. It maxes out at 10 megapixels which is about 4k. 5k is nearly 14 megapixels.

http://superuser.com/questions/441395/what-is-the-maximum-re...

http://en.wikipedia.org/wiki/Red_Digital_Cinema_Camera_Compa...

It'll be interesting to see what Apple does then because 2X the current Thunderbolt Display (how Apple has done hiDPI)would put it above 5k.

Maybe it will take a future version of Thunderbolt using optical cables to do a Retina Thunderbolt Display. Or maybe Apple will simply make it around 4k.

Apple do the 2x stuff on iOS so that the large set of handcrafted, bitmapped 1x apps can map precisely to pixels when you upscale them. OSX doesn't have the same issue, since there's no existing default screen size that is designed for.

Apple is doing 2x on OS X as well. That's how the new Retina MacBook Pro works.

This allows Apple to give users the same exact workspace as before, just with 4x the pixels.

They could break this with the iMac and Thunderbolt Displays, but 2x is how I expect all Mac laptops to be in a few years.

Makes one wonder whether we'll see 21" retina iMacs / Cinema Displays before the 27" versions.

Since Thunderbolt is also some sort of PCIe port, couldn't you have the GPU be internal to the Cinema Display, and transmit only the GPU code over Thunderbolt? Or are significant parts of the screen drawn by the CPU directly these days?

I suppose that would be possible, if the built in GPU has local video RAM and such. You wouldn't nearly be consuming the bandwidth compared to sending raw video to the display.

I do think it would be a little too complicated though, it's probably more likely there will be a faster Thunderbolt port before that happens ;-)

Latency is a much larger problem.

Is there higher latency between Thunderbolt connected components than "regular" PCIe?

Yes. Even with PCIe "extender" ribbon cables of a few inches, you can stumble over latency issues.

Falcon Ridge will deliver 20Gbits/sec per channel (40 total), making the 5K iMac possible. But we will have to wait until 2014.

Doesn't that assume no compression in the transfer? Surely, if streaming compression is getting better, there's some lossless compression that can be used for display signals?

What does your video card/monitor do when it's asked to display a frame that can't be compressed?

Generally these things would have to be done in hardware, bumping up the price by a non-negligible amount. Additionally, it would increase the input lag on the monitor, something manufacturers are trying to avoid.

It would have to be real-time (60 frames a second) and I just don't see significant savings being possible anytime soon.

The new Macbook Pro Retina has two Thunderbolt ports. In theory, they could build a display using both, each driving half of the screen. Although it's unlikely to happen.

Similar things have been done with large displays in the past, though not on consumer hardware.

Would that not be pretty similar to dual-link DVI? Though I believe that was part of the DVI specification whereas I've never heard the current Thunderbolt standards to have provision for such. Regardless, I wouldn't be shocked for Apple to do it at least initially in their own non-standard way.

Dual-link DVI is still one connector. Needing two separate ports to drive a monitor is pretty un-Apple.

hm but i have seen Thunderbolt Macbooks running two 27" Cinema Displays: http://www.youtube.com/watch?v=sP1thwUcO9c

A retina Cinema Display would have the pixels of four Cinema Displays.

Maybe it's just me, but I don't need more than 1080p resolution for watching a video. I don't recall the exact numbers, but I think you need to be within 5 feet of a typical 42" screen to notice an improvement of 4k over 1080p. That's bit close for my taste! Now if you have some kind of enormous video setup that would benefit, then more power to you.

EDIT: I found an article on the subject: http://carltonbale.com/1080p-does-matter/

People would either need bigger TVs and/or to sit closer. It's the same with 1080p vs. 720p.

Ironically, I might be better able to make use of 4k video on a computer since I sit so close. I find video to be a bit soft on the iPad 3 and Retina Macbook Pro because both have to up-convert 1080p video. I expect to have a 4k or so 27-inch monitor in a few years, and would love to be able to watch native video on it.

I would need to both sit much closer and need a bigger TV to make use of 4k video. I still have a 720p plasma because where my couch is, it's almost impossible to tell the difference between 720p and 1080p.

Some of the detail may have been lost in the compression and some in the upconversion so better source compression and better upconversion may help a lot although more resolution is always nicer.

Yeah, I understand why movie theaters are interested in 5k, but I don't think most people will be able to see the difference on home televisions.

Not that that will stop them from making them, but it'll be interesting to see what happens after 4k/5k when the limit of how much resolution the human eye can perceive has been surpassed.

Marginal improvements in apparent resolution aren't the only thing that a more efficient codecs can deliver. The same capacity can also be used to increase the bitrate of the encoded files dramatically, and / or deliver streams at much higher frame rates. In terms of improving picture quality, jacking up these aspects while keeping resolution at less than the supported maximum can be far more effective places to spend your bit budget.

Agreed. If I had twice as much bandwidth available to stream Netflix, I'd much rather have twice the bitrate than 1.4x more pixels in each direction.

I need glasses but rarely wear them. I'm happy watching 480p most of the time.

I have recently acquired weak glasses (0.25). I wear them when I'm watching good HD sources and take them off if there were significant artefacts or low res source as they are better slightly blurred and there is the comfort benefit.

I do care about video quality although I know that I'm in the minority (many people say that picture quality is the most important thing in a TV but very few of them can actually identify it). Given that my very weak prescription makes such a difference (720P and 1080P content is probably the same without my glasses) it wouldn't surprise me if many people really couldn't see it.

This is me, all the time. I have awful vision yet never wear glasses unless I absolutely need them.

Glad to know I'm not alone ;)

In the majority of situations, most people cannot tell the difference between 720p and 1080p. Of course, people who are interested in home cinema type setups ("videophiles"?) will be able to tell immediately.

I think that a major change you will see in the future is the size of the screens. In order to take advantage of a 4k stream a monitor needs to occupy a much larger fraction of your vision than 1080p. So 3 metre screens or projections in people's homes will become more common if resolutions are going to meaningfully increase.

http://carltonbale.com/1080p-does-matter/

The missing words are "well encoded 720p and 1080p". The difference between bandwidth starved cable and over-the-air HD is amazing. Having a new standard that can encode a better picture over cable or satellite is more than welcomed.

I upgraded my Apple TV so I could get 1080p and the main thing I noticed was slower downloads.

I know bandwidth is a problem, but isn't battery consumption a bigger problem? Whatever we lose in bandwidth usage, we gain in power drain, right?

Not if you have hardware support, ie the GPU does the decoding.

I'm not at all familiar with video encoding/decoding processes or what they entail. Can you explain how hardware support for it would drastically change power requirements?

Well, specialized hardware is generally more efficient than general purpose hardware. (see CPU vs GPU for graphics)

So it might use a little bit more power than h264 with hardware acceleration, but probably not all that much.

Sure, specialised hardware tends to be more efficient than general purpose hardware but it's not so much "special-purpose hardware is magic" as it is "the general purpose hardware doesn't take advantage of certain properties". As far as I understand the GPU's advantage over CPU (again, graphics is not my area of expertise) it's largely that graphics processes are massively parallel and the GPU is specifically set up to handle massively parallel things. Like I said, I know nearly nothing about video encoding/decoding so I was hoping someone who did could explain things for me. My only guess for how specialised hardware could dramatically save power for video decoding is that it might be comprised of massively parallelisable simple operations.

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