I was working on the assumption that the degradation in quality was due to the high compression, as it's easy to tell the difference between 720p and 1080p blu-ray without the compression.
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Improved H.264 Compression Holds Down File Sizes on 1080p iTunes Store Content
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I was working on the assumption that the degradation in quality was due to the high compression, as it's easy to tell the difference between 720p and 1080p blu-ray without the compression.
Odd, doesn't the 4S support high profile streams? It came out before the iPad (3rd Generation) as well.
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H.264
It might but not at 1080p.
A 1080p picture is significantly larger than a 720p picture.
1920x1080 vs 1280x720.
This amount to 2.25 the number of pixels and 1.5 increase in both horizontal and vertical pixels.
They can keep the file size down by increasing the quantization.
This does reduce image quality.
From a previous poster, I know the GPU has dedicated decode hardware, but it is not a full implementation of an H.264 decoder. It accelerates the decode but by no means is there a full hardware H.264 decode in the A5x.
It might but not at 1080p.
A 1080p picture is significantly larger than a 720p picture.
1920x1080 vs 1280x720.
This amount to 2.25 the number of pixels and 1.5 increase in both horizontal and vertical pixels.
They can keep the file size down by increasing the quantization.
This does reduce image quality.
From a previous poster, I know the GPU has dedicated decode hardware, but it is not a full implementation of an H.264 decoder. It accelerates the decode but by no means is there a full hardware H.264 decode in the A5x.
Yep I just saw that. It wasn't on there last night. I was trying to see if my Avatar had a 1080p option and when I checked it again today I saw it only said 720p (where there was different info there before).
You kind of sum up the flaw behind 720p and 1080P.
You won't notice a difference on a smaller screen. 1080P and 720P cannot be distinguished by the human eye on screens 52" or smaller. It's mostly a marketing hoax.
What usually makes say, a 42" 1080P set look better than a 720P set next to it isn't the pixels, but the other hardware and software differences in the sets. Hrtz, refresh, color handling, etc. If a 720P set had the same exact hardware and software of a 1080P you'd never see a difference until the screen size hits around 52". The only other factors can be the distance you are from the TV, but most people aren't sitting five inches in front of their TV set.
With these comparison images, you have to factor in compression as a reason for better brightness and the like.
Now, people who don't want to believe science will argue that what I said is totally wrong... because they often don't want to feel they over paid for something they did not need... but you can google all this and verify. CNET is often posting articles with the hard science (on the human eye especially) and people in the comments still want to insist it's wrong.
The same is true of higher audio. The human ear at a certain point can't hear the extra quality, making it a waste of someones money and just bragging rights on a system.
I personally don't know if I totally buy the 52" inch size... I kind of dispute the science at around 47" but that's when distance from the screen becomes more relevant.
It's too bad they don't offer a higher powered AppleTV for those of us that would sacrifice a few more dollars to have better capability. The fact that the iPhone can decode a higher standard (4.1) compared to the new AppleTV (4.0) at its release time indicates there could still be possible issues for content in the future if a 3rd party is using 4.1 and you're wanting to play it on AppleTV and cannot because they only put in a single core A5 in there.
I'd think that if Apple wants to move to apps (or heaven forbid, actual console gaming), they'd want more than that single core A5 in there. You probably could not even play many newer iOS games even if it did support it due to a need for more power.
I'd like to see support for the newer Blu-Ray audio standards (DTS True HD) and that might be a bit more taxing as well, but those of us that want to encode our own Blu-Rays would want as much quality as possible for playback on the AppleTV. I also find it odd that Apple now apparently supports .AVI all the sudden, but doesn't offer .MKV container support, the latter of which supports DTS while .m4v does not (I guess users that want it will still need to hack for XBMC).
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So...because you have no sense of humor, you can't comprehend why others would like the show? Is your name Sheldon by any chance?
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That's not true either. It depends entirely on the viewing distance relative to the size of the screen.
See: http://s3.carltonbale.com/resolution_chart.html for a chart showing the resolution vs. viewing distance capability of the human eye.
Because it is your only device? And connectivity?
Point is, the sources of media and the pipes to get it to us are not in sync. Might be nice if someone looked at that someday.
You are incontrovertibly wrong about that.
I don't know about you, but when I upgraded my iPhone 3G to a 4S I saw a remarkable difference in screen clarity. Now I don't have the specs in front of me but I'm sure my phone's screen is less than 52"
Are you justifying your own purchase of a TV under 52", per chance?
I work with footage all day, everyday, from 720p content to 4K. I assure you there is a marked difference between resolutions. Your comment is only half-true, at best, of overly compressed video that has literally removed all the details from the image. As MagnusVonMagnum said, it is entirely to do with viewing distance.
Also, best not recommend someone to go to CNET for "science"
Would apple's source not be 8bit anyway? Bluray discs/spec isn't 10bit so there's no advantage in quality, only a slightly lower bitrate for the same quality - This sounds good in theory of course, but I can't think of any device (from £5 arm socs to £500 gfx cards) that'll play this in hardware without issue. If a 3+ghz i7 struggles, a single core arm won't stand much chance with software decoding
Apple are just switching to a high profile that's been 'standard' for years - Real, great and innovative news would be that Apple had switched to using x264 for their encoding!
The AppleTV2 since the last update can playback can play back virtually anything in 1080p. Hasn't failed on anything i have thrown at it yet.
lolwut
ha ha i don't understand why people are praising apple for upgrading to 1080p while only upping the file size marginally. H.264 is the same video compression standard that at&t uses for their U-Verse tv and we all know how much U-Verse's picture quality sucks. When you go to 1080p from 720 with only a marginally higher bit rate, you are going to have a very bad picture, even worse than what you would've had with 720p. You are basically bit-starving the feed. The only good thing the 1080p will do is give you a sharper image during slow moving or still shots. During times of high-action, this is when the bit-starving really gets seen. You'll start seeing compression artifacts, macro blocking, inaccurate colors, and a whole other mess. The general public watching these movies may not notice, but it will be very obvious to people who care about picture quality. The current 720p HD movies on iTunes have a bit rate of about 4.5mbps. U-Verse (bad quality picture) is about 5.7mbps. Your local cable/satellite is around 8-12mbps. Verizon fios is 15-20mbps. And blu-rays are around 30-40mbps bit rates.
ha ha i don't understand why people are praising apple for upgrading to 1080p while only upping the file size marginally. H.264 is the same video compression standard that at&t uses for their U-Verse tv and we all know how much U-Verse's picture quality sucks. When you go to 1080p from 720 with only a marginally higher bit rate, you are going to have a very bad picture, even worse than what you would've had with 720p. You are basically bit-starving the feed. The only good thing the 1080p will do is give you a sharper image during slow moving or still shots. During times of high-action, this is when the bit-starving really gets seen. You'll start seeing compression artifacts, macro blocking, inaccurate colors, and a whole other mess. The general public watching these movies may not notice, but it will be very obvious to people who care about picture quality. The current 720p HD movies on iTunes have a bit rate of about 4.5mbps. U-Verse (bad quality picture) is about 5.7mbps. Your local cable/satellite is around 8-12mbps. Verizon fios is 15-20mbps. And blu-rays are around 30-40mbps bit rates.
What is all this about? We have a 40" HD TV and a Bluray player since last December (yes, we were sticking with our good old tube until then to make sure the technology matured enough and our old TV was still good anyway) and an Apple TV 2.
Honestly, the difference between 720p and 1080p is so marginal when watched from a normal distance to the screen (before somebody asks: I have very good eyes), that I couldn't care less if the Apple store is offering content in 1080p. Most viewers probably don't even see a difference at all. It is just pure marketing. And how many users really do HD projection or have a huge 60+" TV screen? I know, in North America the TV is still the "altar" in the average household and TVs tend to be way bigger there compared to here in Europe, but here I don't know anybody who has a TV that is bigger than 50". Is everybody sitting with their nose glued to the screen, counting pixels with a loupe?
Even good DVDs look not too bad, when upscaled with a good algorithm. DVDs of a few months old movies are so cheap now (not much more than renting), that in some cases we still go for the DVDs. At least we are compatible to everyone then.
On a side note: We are living in a "post PC" era, because the computers can do everything we need them to do since a few years and people don't get, why they should buy a new one still every 2 years. But still everyone has one and uses it. Nowadays you only buy a new one, when it really brakes. My daughter has a 2008 Macbook and it still has more power than she'll ever need in the next few years. We just had to replace the battery and the Combo-Drive is dead (which I will replace with one from a perfectly running Mac mini that is collecting dust in my office, because Apple decided to ****** their customers by not letting SL computers sync with iCloud). So we live in a post PC era because the industry can't sell as many PCs anymore as they used to. The product is more than mature. But does anybody honestly think, that people don't use their computers anymore in a few years? An iPhone or iPad will never replace a real computer, but complement it. There are things that I just can't do with an iPad or iPhone, no matter how hard they try to migrate consumer applications to them.
What has all this to do with TVs? If you haven't figured it out yet, ... I am too lazy now.
Just my 0.02€
Have a great weekend
groovebuster
Honestly, the difference between 720p and 1080p is so marginal when watched from a normal distance to the screen (before somebody asks: I have very good eyes), that I couldn't care less if the Apple store is offering content in 1080p. Most viewers probably don't even see a difference at all. It is just pure marketing. And how many users really do HD projection or have a huge 60+" TV screen? I know, in North America the TV is still the "altar" in the average household and TVs tend to be way bigger there compared to here in Europe, but here I don't know anybody who has a TV that is bigger than 50". Is everybody sitting with their nose glued to the screen, counting pixels with a loupe?
Even good DVDs look not too bad, when upscaled with a good algorithm. DVDs of a few months old movies are so cheap now (not much more than renting), that in some cases we still go for the DVDs. At least we are compatible to everyone then.
On a side note: We are living in a "post PC" era, because the computers can do everything we need them to do since a few years and people don't get, why they should buy a new one still every 2 years. But still everyone has one and uses it. Nowadays you only buy a new one, when it really brakes. My daughter has a 2008 Macbook and it still has more power than she'll ever need in the next few years. We just had to replace the battery and the Combo-Drive is dead (which I will replace with one from a perfectly running Mac mini that is collecting dust in my office, because Apple decided to ****** their customers by not letting SL computers sync with iCloud). So we live in a post PC era because the industry can't sell as many PCs anymore as they used to. The product is more than mature. But does anybody honestly think, that people don't use their computers anymore in a few years? An iPhone or iPad will never replace a real computer, but complement it. There are things that I just can't do with an iPad or iPhone, no matter how hard they try to migrate consumer applications to them.
What has all this to do with TVs? If you haven't figured it out yet, ... I am too lazy now.
Just my 0.02€
Have a great weekend
groovebuster
Encoding is always a matter of compromise between size with quality, but if you switch to a more sofisticate encoding profile you can get much better quality for the same size or same quality with much smaller size, usually at the price of higher processing power requirements when decoding.
If they just compress more with the same profile they are not doing a good job, I hope (and guess) they actually employ a better encoding profile instead.
Yes, because I do not like this one show I have zero sense of humor. Arrested Development is a funny show, so is the original Office and Extras, how about Monty Python's show and movies? How is it possible I find these things funny with no sense of humor?So...because you have no sense of humor, you can't comprehend why others would like the show? Is your name Sheldon by any chance?
The fansub scene was in an uproar to move to Hi10P to reduce file sizes. 720p episodes are getting under 200 MB like it once was with 480p.Would apple's source not be 8bit anyway? Bluray discs/spec isn't 10bit so there's no advantage in quality, only a slightly lower bitrate for the same quality - This sounds good in theory of course, but I can't think of any device (from £5 arm socs to £500 gfx cards) that'll play this in hardware without issue. If a 3+ghz i7 struggles, a single core arm won't stand much chance with software decoding
And that is what happens when you have an informed user base...
![[DL]](/data/avatars/m/410/410081.jpg?1266785706){kind=avatar}
It's Apple's way of promoting BD.
(I'd love to see the BD screen capture of that same frame side by side with the Itunes versions....)
The fansub scene have pretty much always been at the forefront of and pushing for new and improved encoding technologies.
Hi10P certainly caused an uproar and lots of division, because it's not necessarily an improvement. Banding etc. improvements are very arguable over other quality encodes, currently it's basically all about file size.
We've got some groups continuing as they were, some groups moving to Hi10P only and other groups providing both. Personally I think it's a bad thing - Reduced file sizes (should we really care that much about this, especially when it comes to archiving anime?) at the cost of moving ALL decoding to software. When these cheap media streamers, SOCs, vdpau and vaapi etc mature I'll be all for it but unlike the past, I think some of these groups have made the wrong decision and don't really see it as pushing forward.
Don't really know understand what you mean by this - The h264 world would be a better place if x264 was the only encoder - But for all these multi-billion pound production studios, why use the best solution available for free when you can spend £100000s on something substandard?