Comparison finds iTunes 1080p video nears Blu-ray disc quality
The image quality of Apple's newly released 1080p encoded movies hold their own in a qualitative comparison with the highest resolution consumer format available Blu-Ray Disc.
Despite a substantially smaller file size, 1080p movies from iTunes perform admirably against identical offerings in the Blu-Ray format, showing good sharpness and color saturation, reports Ars Technica.
The test was based on still and moving images from the movie '30 Days of Night,' which were viewed on a 1,920x1,080 pixel Dell U2312HM monitor. An MacBook Air piped the iTunes content to the display through DisplayPort, while a Panasonic DMP-BD65 served as the test bed for the Blu-Ray version of the movie.
The iTunes download came in at 3.62GB and includes Dolby Digital 5.1 sound as well as a stereo AAC track, and is being compared to the 50GB-capable Blu-Ray Disc which adds a DTS-HD option to the standard Dolby Digital 5.1. Also included on the physical disc are special video features and other extras.
In the report's findings, the H.264-compressed iTunes media was close in image sharpness, though a bit of anti-aliasing produced a slightly softer image in scenes with great detail. On the whole, however, the differences are only clearly seen when making pixel-to-pixel comparisons and may not be noticeable if watched from a proper viewing distance.
Sharpness is somewhat comparable to Blu-Ray in all but the most detailed scenes. | Source: Ars Technica
Color was another area where the iTunes version shined, exhibiting good standard saturation and comparable accuracy against the Blu-Ray reference image. It should be noted that all current display technologies are capable of reproducing the color gamut of a Blu-Ray Disc, and thus makes this particular test somewhat inconsequential.
One metric where Blu-Ray trumped its iTunes competitor was contrast, where the Apple encoded video saw a marked decrease in detail at the spectrum's extremes. In the provided image still, highlights are blown out and nuanced detail within the shadows was all but lost. Video compression often constrains the visible spectrum in order to save space, and iTunes' implementation is no different.
Another space-saver is the smoothing of "film grain" and noise, factors that the capacious Blu-Ray Disc doesn't need to fret over, which is why during panning shots or highly detailed scenes are rendered slightly mushy in the Apple version. Unlike still photography, where noise is usually unwanted, the grain in moving images adds a perceived detail that lends itself to a "movie look."
Grain is clearly represented in the Blu-Ray version (right), but slightly smoothed out in the iTunes copy (left). | Source: Ars Technica
The achilles heel to most highly-compressed video formats is gradients, and H.264 is no exception. In the Blu-Ray version, a cloudy night sky is represented faithfully, with smooth transitions and no detectable amount of banding. The iTunes copy, however, shows significant amounts of banding, which presents itself as a sharp steps between gradients that should otherwise be smooth.
Banding is obvious in the iTunes video (top). | Source: Ars Technica
Despite a few shortcomings, the new 1080p option for iTunes users looks to be worthwhile, especially given the immense savings in space and lack of physical media.
[ View article on AppleInsider ]
Comments
Uh oh. People who've wanted Apple to support Blu-ray are not going to like this at all.
I except a lot of pedagoguing on why on true videophiles use Blu-ray to ensue shortly.
I'm sure as bandwidth improves the file size / quality will creep up to keep pace, but at my current broadband speeds ordering the blu ray from amazon would probably see me watching the film sooner than attempting to download 50Gb so I'll happily take the _much_ smaller download size with _slightly_ poorer quality...
Whiny people who whine about Blu-Ray not coming to Macs should just put a big fat sock in their mouths, 'cause it aint gonna happen. Who wants or needs physical media anymore? Step out of your caves you clueless prehistoric people, and join the 21st century.
Blu-Ray is clearly (and unsurprisingly given the vast difference in bit-rate) vastly superior to the iTunes encodes when it comes to banding and to me it is therefore a bad joke to suggest the two are anywhere close to being on a par.
You should use rip the BD to HD, then on same computer, use software to play the movie and do screenshot, and compare the uncompressed TIFF or high quality JPG.
If you have to use camera to shoot the screen, you should use the same display device.
BTW, I don't mean itune version is not good at all. I just mean the way to compare.
That's pretty damn close to Blu-Ray:
Please, for everyone's sake, don't drive until you get your eyes checked and get the appropriate corrective lenses.
Instead of using crappy screen images (which, in some cases do show noticeable differences) from a mediocre 23" LCD, do the same test on a good quality 50" or bigger plasma then get back to me.
I expect this type of garbage analysis from AI, but from Ars??
UPDATE: Turns out, "30 Days of Night" wasn't even the best BD transfer. From http://www.blu-ray.com/movies/30-Day...Blu-ray/13310/
30 Days of Night: Dark Days' roots as a mid-budget DTV picture are evident throughout Sony's passable 1080p, 1.85:1-framed Blu-ray transfer. The image never escapes the HD video appearance; it delivers stable detailing that occasionally spikes to eye-catching levels but that never quite reaches the same level of excellence that might be found in a properly transfered-to-Blu-ray image sourced from a pristine 35mm film print.
-kpluck
That's pretty damn close to Blu-Ray. Those comparison shots look pretty impressive, and an iTunes file is of course much smaller than a Blu-Ray file.
Whiny people who whine about Blu-Ray not coming to Macs should just put a big fat sock in their mouths, 'cause it aint gonna happen. Who wants or needs physical media anymore? Step out of your caves you clueless prehistoric people, and join the 21st century.
Why don'y you tell us what you really think?? You may not realize it, but that is all it is, what YOU think..
I really don't care whether Apple supports Blu-ray or not, because that's not where the money is, for them.. But I will never give up the quality of Blu-ray.. And to ME video quality is only half of the full HD experience.. The audio on Blu-ray is amazing.. And I do have the setup to take advantage of the audio on Blu-ray..
Like most people today who grew up listening to mp3s, they will never know what true high fidelity music is.. And now thanks to streaming video, then will never know the quality they are missing..
Just like Windows is "good enough" for the people who use it.. I guess video downloads is "good enough" for people who don't know any better..
. . . Step out of your caves you clueless prehistoric people, and join the 21st century.
Off with the gloves, Apple ][! Say what you really think.
Looks like LMGS beat me to the punch. kudos. However . . .
I noticed when the huge screen movies were brought out, shortly after the movie was on the way, it was the movie that was important. Lousy movie huge, was still a lousy movie. Great movie huge, great was great what ever. 10+ times the size for marginal improvement? And then wait 10 minutes and the movie is what it is. All you get with the extra expense are bragging rites.
Please, for everyone's sake, don't drive [a car...]
And we're off... Hyperbole takes a strong lead out of the gate.
Like most people today who grew up listening to mp3s, they will never know what true high fidelity music is.. And now thanks to streaming video, then will never know the quality they are missing..
You mean the "high quality" DVD and VHS that existed before streaming videos?
Bottom line: Apple's 1080p is better than their 720p and costs the same price. Apple's 1080p is the best of the major online video services.
Bring on 4K displays.
Why don'y you tell us what you really think?? You may not realize it, but that is all it is, what YOU think..
Not really, because my main claim is that Blu-Ray is not coming to Mac. And that is reality, not merely my opinion. It's been how many years since Blu-Ray has been out on the market?
If Blu-Ray is important to somebody, like you say it is for you, then you already have a dedicated Blu-Ray player for that. Everybody else will be more than happy with the quality of something like an iTunes download.
In a sentence, a highly compressed video is not quite as good as a less compressed one... Who would have thought? /s
My thinking exactly.
I'm willing to concede that a 1080p download from Apple is not as high a quality as blu-ray. And for some people, the different might be important - so they will have to buy the blu-ray disk for the player that they undoubtedly have attached to their TV.
However, for most people, the trade-off is quite acceptable. For me, while I can tell the difference between blu-ray and dvd, I have to be actively looking for it and it doesn't really add much (if anything) to the movie. I have yet to see a movie that I enjoyed significantly more in blu-ray than in DVD. The tiny difference just doesn't matter to me. And I suspect to a very, very large number of people.
You have to remember that there are plenty of people still alive (including myself) who grew up with black and white and then early color TVs. If I could enjoy the first Star Trek TV shows on a mid-60's color TV with all of the interference and static that our remote location engendered, even DVD quality is miraculous.
You have to remember that there are plenty of people still alive (including myself) who grew up with black and white and then early color TVs. If I could enjoy the first Star Trek TV shows on a mid-60's color TV with all of the interference and static that our remote location engendered, even DVD quality is miraculous.
Back in my day we didn't have a choice of black or white, it was one or the other, and we only got one frame per second of this fancy 30 fps crap.
That's pretty damn close to Blu-Ray. Those comparison shots look pretty impressive, and an iTunes file is of course much smaller than a Blu-Ray file.
Whiny people who whine about Blu-Ray not coming to Macs should just put a big fat sock in their mouths, 'cause it aint gonna happen. Who wants or needs physical media anymore? Step out of your caves you clueless prehistoric people, and join the 21st century.
There is no comparison to "Blu-ray Disc", especially when you blow the image up to something larger than your 20" iMac and listen to it with Dolby TrueHD or DTS-HD Master Audio on something better than your HK Soundsticks!
No need to step out of my "ManCave" when I have the disc already in hand and on the day of release. I can watch it any time and don't have to worry about limited bandwidth or the cable/internet being out. All I need is AC and I'm set to go. And, my discs will still be able to spin in the 22nd century!
If you were to go to a movie theater and watch something with iTunes 1080P quality, you would certainly be asking for your money back. The quality of Blu-ray Disc is about as close to theatrical distribution quality digital video as you are going to get, and it is designed for home use. Your are the one that is clueless about quality. The two formats should co-exist, for those that don't want to collect and for those that do.
I have to disagree with the article's conclusion. It's all about that final comparison that clearly shows banding in the iTunes version. Banding is obvious when it occurs (as opposed to other things such as "sharpness" which often require zooming in and doing pixel-to-pixel comparisons) and to me is highly distracting and annoying.
Blu-Ray is clearly (and unsurprisingly given the vast difference in bit-rate) vastly superior to the iTunes encodes when it comes to banding and to me it is therefore a bad joke to suggest the two are anywhere close to being on a par.
I completely agree. I hate the banding in Netflix and iTunes movies. It is very noticeable and annoying. It's a great step forward but Blu-Ray is still the best movie experience.
Back in my day we didn't have a choice of black or white, it was one or the other, and we only got one frame per second of this fancy 30 fps crap.
And we had to act as our own antennas...
And don't get me started on tuning in UHF stations.