Revisiting 1080p24 ("24p") on Blu-ray

Not too long ago I posted 1080p24 ("24p") on Blu-ray to talk about how, for the first time on home video, a motion picture is rendered on Blu-ray disc just the way it was recorded on film: at 24 full video frames per second. Using "progressive" 1080p video, films on Blu-ray can be stunningly realistic when viewed on a 1080p HDTV connected to the Blu-ray player via HDMI. In contrast, I said, DVDs generally don't store progressive video, at the 24 frames per second used by motion picture film, or at any other frame rate.

Recently, an anonymous person added this comment to my post:

Dear Bonehead,

I stopped reading your article partway through because you obviously know NOTHING about the DVD standard. NTSC DVD's support both "30fps" (interlaced video) and 24fps (progressive scan video); in fact, most Hollywood DVD's use 24fps when the original source is film to save on disc space (by eliminating 6 fps of interpolated data), as the DVD player will do 2:3 pulldown as necessary when outputting to an interlaced display. Blu-ray just adds extra resolution to the image, not a "breakthru" in frame rates or progressive scanning. Bother to do your research before blathering on the internet like you are some sort of expert. I don't know everything, but I do know something about DVD's, as I work with encoding and authoring them everyday for my job.

Now, I can take being called names like "Bonehead" when my name-caller has any kind of a good point to make. In this case though, not only was the anonymous commenter rude, but he was just plain wrong, to boot. So here is my rejoinder:

Sorry, you who so impolitely called me "Bonehead," but I beg to differ:

On DVDs sold in the United States, film-derived video is recorded in such a way as to result in 480i output from a standard DVD player — that is, interlaced video with two fields per video frame, separated by a time interval of approx. 1/60 second between fields. The frame rate is thus approx. 30 frames per second.

The typical "progressive scan" DVD player (one that does no "upconversion") can derive 30 complete, non-interlaced frames per second from film-based video on an NTSC DVD and output those frames as 480p video on a component-video connection, into a TV whose component-video input can handle the bandwidth of 480p. It cannot, however, output progressive video at 24 fps. Only a Blu-ray player, using a Blu-ray disc, can do that.

To derive progressive output at 30 frames per second from film-based material, the progressive scan DVD player can simply take each video field and "double" the scan lines in it, to make up a full frame with 480 scan lines. This is the "line doubler" approach.

A smarter approach is to do "3:2 pulldown compensation," a.k.a. "2:3 pulldown compensation" or "inverse telecine." Ideally, this process faithfully recreates the 24 frames per second of the original film —— but then 6 of those 24 frames are repeated(!) to bring the video-output frame rate up to 30 frames per second. This is done because few if any of the TVs that were available when progressive scan DVD players were introduced were able to accept video at 24 frames per second.

On the DVD itself, the encoding is 480i. However, film-based material is usually — but not always — encoded in such a way that the video fields that need to be repeated (in "2:3 pulldown") to change the 24 frames per second of film into the 30 frames (or 60 fields) per second of NTSC video are flagged, with the DVD player being expected to use the flags to re-output the fields as necessary.

This use of flags to tell the player how to do 2:3 pulldown is called "soft telecine." In "hard telecine," the fields are actually repeated on the disc. Few progressive scan DVD players know how to compensate for "hard telecine." They typically do know how to compensate for "soft telecine" — but, unfortunately, many DVDs using that type of encoding have portions where the flags are missing or improperly used, resulting in imperfections in the output cadence until the flags get back in sync.

"Soft telecine" 480i DVDs record exactly 24 frames per second, or 48 fields per second. They accordingly bear a superficial resemblance to the "24p" recording of a film on Blu-ray, but the latter is truly recorded as progressive video at 24 frames per second, while the former records discrete fields of interlaced video at 48 fields per second.

In saying the above, I realize that I am in disagreement with the Wikipedia article on 24p.

The section "24p on DVD" states, "DVDs, however, are capable of storing the native 24p frames." This is possibly true. It also states, "Every Hollywood movie is laid to disc as a 24p ... stream." This is definitely not true.

True 24p is at best an optional way to encode DVDs that is rarely if ever used. It is not actually used for "every Hollywood movie." See this page at the website dedicated to the Handbrake video transcoder software, if you don't believe me about most or all film-based NTSC DVDs being either "soft" or "hard" telecined. Also see this page about the MPlayer and MEncoder software. The format discussed at "11.2.2.2. Telecined" is the one used on virtually every film-based NTSC DVD.

Still don't believe me? Let me refer you to perhaps the ultimate authority on DVDs, Jim Taylor, who wrote the book DVD Demystified and maintains the Official DVD FAQ. He says, in "What's a progressive DVD player?":

A progressive-scan DVD player converts the interlaced (480i or 576i) video from DVD into progressive (480p or 576p) format for connection to a progressive-scan display (31.5 kHz or higher) ... There's enormous confusion about whether DVD video is progressive or interlaced. Here's the one true answer: Progressive-source video (such as from film) is usually encoded on DVD as interlaced field pairs that can be reinterleaved by a progressive player to recreate the original progressive video.

OK, that's about the size of it, then. Virtually all NTSC DVDs in the United States that were sourced from film have telecined video encoded on them, which means interlaced, not progressive, video. Any more questions, Anonymous?

TCM HD arrives!

It's been a long time coming, but Turner Classic Movies is now available in 1080i HD! The channel adored by lovers of, yes, classic movies is not just a standard-def affair any more. As of November 28, 2009, Comcast — at least in my area of Baltimore County, Maryland — carries TCM HD. In my area, it's on digital channel 890. That means TCM HD ought to be coming to other cable systems soon, if it hasn't already.

TCM has long been adored by millions of cable TV viewers because it screens movies of the past from its huge vault. It shows them uncut, sans commercials, in their original aspect ratio. The TCM database contains over 150,000 titles; surely not all of those appear on the TCM channel, but the number of films that do show up on TCM is gargantuan.

That "original aspect ratio" thing is big, by the way. OAR applies to movies shot in wider than the 4:3 Academy ratio of Hollywood's Golden Age. TV screens used to be 4:3 too, so Golden Age movies fit them perfectly. But OAR rendering of widescreen flicks — as opposed to "panning and scanning" to fill the entire 4:3 TV screen with selected parts of the original film frame — meant putting letterboxing bars at the top and bottom of the screen. Many who were not celluloid cognoscenti hated the bars. The cognoscenti loved them.

Along came today's 16:9 widescreen behemoths, and OAR still meant putting letterboxing or "matte" bars at screen top and bottom, for the oodles of movies whose frame dimensions are notably wider than 1.7777...:1 (which is 16:9 reduced to a decimal value). CinemaScope from the 1950s, in particular, was 2.35:1!

If you want to see all of Around the World in 80 Days (1956) or 20,000 Leagues Under the Sea (1954), among countless other memorable spectaculars of the era, you have to see them in OAR.


If you want to see great movies shown to their best advantage on TV, you also need to see them in HD. People who have Blu-ray players know that. Still, it may be years before Around the World in 80 Days and 20,000 Leagues Under the Sea show up on Blu-ray. Having TCM come into our homes in 1080i gives us hope that one day soon, even before said titles come to Blu-ray, such fare may be visible in a format putting over 2,000,000 pixels on the TV screen.

But there remain obstacles. Whether TCM shows 20,000 Leagues or ATW80 in glorious HD on its HD channel, or simply upconverts it from a standard-def version, is a huge question.


It all has to do with how TCM's vault copy of the title has been transferred from film to video.

Today, film-to-video transfer is usually done using film scanners. These are devices that you feed a reel of celluloid into, wait a very long while while the scanner records every tiny detail of every film frame, and out comes a digital copy in a high-definition-plus video format such as 2K or even 4K.

2K: that's "one K" — "K" refers to the power-of-two number 1,024, not 1,000 — multiplied by two, yielding 2,048, which is the number of pixels per row or video scan line in the digitally scanned 2K output. So each frame of video in the 2K output has 2,048 pixels in it. That makes its resolution better than that of 1080i/1080p HD, because 1080i/p video frames have only 1,920 pixels per row.

4K scans double the 2K per-row number, to 4,096 pixels per row.


2K and 4K scans have varying numbers of pixel rows. They generally have 1,152 and 2,304 pixel rows, respectively, for images using the 16:9 aspect ratio — see the Wikipedia article List of common resolutions. Those numbers are 9/16 the number of pixels per row.

CinemaScope and other super-wide film formats have aspect ratios that exceed 16:9, so for them, 2K/4K scans have fewer than 1,152/2,304 pixel rows. And there are many widescreen films whose frames have, say, the moderately narrow 1.66:1 aspect ratio, so 2K and 4K scans will have more than 1,152 and 2,304 pixel rows, respectively.

But never mind the exact number of pixel rows. 2K or 4K resolution is still better than 1080i/p. The true figure of merit is how many pixels there are per row.


Here's a graphic from the Wikipedia article Digital cinematography that shows what's going on:



The assumed aspect ratio in this illustration is 2.39:1, which is quite a bit wider, proportionally, than the 1.77:1 of 1080i/p or 720p HDTV. That means a 2K scan of the 2.39:1 film will have 857 pixel rows, and 4K will have 1,714 rows. (To get the number of pixel rows, divide 2,048 for 2K, or 4,096 for 4K, by 2.39, and round fractional values up.)

This illustration represents, for each resolution, the relative number of pixels per video frame in the scanner's output. As displayed on a video screen, of course, all the resolutions would exactly fill the width of the screen. But a 4K scan would have twice the detail of 2K in the horizontal dimension and twice the detail in the vertical dimension. Hence, the respective sizes of the rectangles in the illustration represent not the image size but the amount of detail present in the various video scans.

1080i/p and 720p use a narrower-than-2.39:1 aspect ratio, 1.77:1, so when a 2.39:1 film is being scanned in OAR for 16:9 HDTV, letterboxing bars do generally need to be added. Some of the resolution that is available in the vertical dimension of the HDTV screen is accordingly wasted. Film cognoscenti don't mind; they'd rather see the film in OAR.

Moreover, the film scanner may eschew adding the letterboxing matte bars under the assumption that they will be added at some later stage of the film-to-TV-screen "bucket brigade."


TCM HD might ideally like to have 2K or 4K scans for each film in its vaults. For showing on the 1080i TCM HD cable channel, each 2K/4K archive copy would need to be downconverted to 1080i.

Another option would be to start with, specifically, a 1080p scan of any given film. Each frame of the film would be scanned to a single frame of the film scanner's 1,920 x 1,080-pixel video output. There are 24 frames per second in film, so there would be 24 fps of video output from the scanner. Each video frame would represent the entirety of one (and only one) input film frame.

The result would be "1080p24" video, where the "p" says that the video frames are "progressive": they're not separated into two video "fields" per frame, with each digital video field carrying, in odd-even alternating sequence, just the odd-numbered or just the even-numbered pixel rows of the image. Video in which there are alternating fields is "interlaced." The "i" in 1080i says the video is interlaced.

Progressive video is more filmlike than interlaced video. Films on Blu-ray use progressive video at 24 fps, and many modern HDTVs can input 1080p24 video from a Blu-ray player over an HDMI connection. That gives the ultimate in video quality on an HDTV screen.

TCM HD is stuck with transmitting 1080i video. It can't use 1080p, because cable TV (even when digital) isn't able to carry that video format; 1080p uses too many bits per second of channel bandwidth. Cable TV has to use 1080i, not 1080p. Furthermore, cable TV has to use 1080i at 60 video fields per second — "1080i60," it's called, or "1080i @ 60 Hz". That field rate amounts to 30 video frames per second, but the second half of the information in each frame arrives 1/60 second later than the first half.

If TCM has in its vaults a 1080p24 video transfer of a film, it can convert it to 1080i60 for cablecast. There are technical issues that affect the video quality of the result, but the conversion itself is otherwise pretty straightforward.


Among the technical issues involved in converting 1080p24 to 1080i60 is the need to avoid "interlace artifacts." One of the most problematic of the interlace artifacts has to do with scene details that are very small — smaller in their vertical dimension than the height of two adjacent scan lines or pixel rows.

In interlaced scanning, such tiny scene elements can, either wholly or partially, briefly disappear. That can happen when, for example, there is a diagonal camera pan with respect to a stationary scene. In any given video field, a tiny element of the scene may happen to partially or wholly coincide with a pixel row that is missing in that field. If so, the detail simply isn't fully represented in the field — if it's there at all.

In the very next video field, the same detail may have moved slightly with respect to the frame of the picture, owing to the camera pan. Now the detail may show up in its entirety, or only partially, or (again) not at all. In the next field in the sequence, it may show up to a different extent — and so on.

To the eye, the result of all this fine detail being shown to varying degrees in successive video fields may be an impression of false shimmering or flickering in the picture.

This is why interlaced video is often filtered. In the vertical direction with respect to the video screen, a (today, usually digital) filter can be used to remove details of the picture that may cause shimmer.

Unfortunately, filtering to avoid interlace artifacts such as shimmer also reduces the amount of "good" vertical detail in the picture, softening the image somewhat even while retaining all of the image's horizontal detail.


Yet another option is for TCM HD to convert to 1080i a lower-resolution film-to-video transfer for a given film.

For example, TCM might have in its vaults a DVD-quality transfer of, say, Alfred Hitchcock's 1954 classic Rear Window. If it's DVD quality, that means it's probably in the 480i format. There are 480 pixel rows per field in the interlaced video, and there are (up to) 720 pixels per row. The pixels don't have the square shape of the pixels in the formats I just talked about, so when the image is spread across a wide 16:9 screen, the apparent resolution isn't as great as it might otherwise be.

(Actually, since Rear Window was shot with an aspect ratio of 1.66:1, which is narrower than HDTV's 16:9, this film would likely be shown on TCM HD with thin vertical letterboxing bars at the sides of the screen. Or, since the term "letterboxing" properly refers to horizontal matte bars only, the term "pillarboxing" can be used instead.)

Moreover, there are 60 fields per second in this hypothetical 480i scan of Rear Window. Since 60 fields per second is not a multiple of 24 frames per second, some of the fields will have to be repeated an extra time. This creates so-called "telecine judder" — telecine (which can be pronounced with three or four syllables) being how film was transferred to video before there were digital film scanners. That word, telecine, refers to the machine that was used, and also to the process of using it.

Telecine judder shows up quite readily when there is a smooth camera pan across a scene. It looks herky-jerky instead. (Fast pans always involve some so-called "strobing," even when a pristine copy of the film is projected on a theater screen. Telecine judder simply accentuates it.)


If TCM HD shows this "480i60" (as it's technically called) hypothetical scan of Rear Window, it must first be upconverted to 1080i60.

Converting among different digital video formats is called scaling. Going from a lower resolution to a higher is scaling up or upscaling. These are both synonyms for upconverting.

The result of upscaling 480i60 to 1080i60 would be noticeably less video resolution than true 1080i60, because video upconversion can never increase true resolution.

There would be just as much telecine judder as in the 480i60 transfer.

Moreover, there could be nasty video artifacts visible in the image that results from the upconversion. Such artifacts might include aliasing, making for spurious moiré patterns in the picture:



(Click the image to enlarge it, then look at the brick walls behind the girl to see the false moiré pattern.)

The aliasing/moiré artifact in a still picture such as that one can get worse when parts of the scene are in apparent motion. If a TV camera taking a picture of a brick wall zooms outward, when the apparently "moving" bricks get small enough, moiré can suddenly appear.

Similarly, upconverting a video image, done clumsily, can in effect add "tiny bricks" (false detail) that can then lead to the shimmering problem described earlier on camera pans, if the added false detail is not filtered out of the 1080i image (along with "good" detail, unfortunately).

In fact, technically speaking, aliasing, the moiré effect, and shimmering and similar interlace artifacts are all examples of the same underlying problem: image details that are, in size, too near to the sizes of individual pixels or (for interlaced video) pixel rows.

There are other artifacts, too, that can appear (or be accentuated) when upscaling digital video from a lower resolution to a higher is done. That's why it is to be hoped that TCM HD will ultimately replace its non-HD vault copies with 1080p, 2K, or 4K scans — or, better yet, 8K scans! — which can then be skillfully downconverted to 1080i with (hopefully) a minimum of visual artifacts.

Apple TV Potpourri

It's been a while since I said much about my (count 'em, two) Apple TV units. About time I rectified that ...

In case you missed it — admittedly, an easy thing to do — Apple's Steve Jobs unveiled the Apple TV in Sept. 2006 as a sort of home theater-connected iPod on steroids. You were expected to connect the petite box, less than eight inches square, to a TV or home theater system. Then iTunes on your computer would sync songs, videos, podcasts, photos, and other digital content to it's hard drive, just as with an iPod or iPhone. You could then play that content through your home entertainment system and/or HDTV.

Apple shipped the first Apple TVs in March 2007 — to deafening silence, aside from the technorati, most of whom held their collective noses. Sales were abysmal. I won't detail all the complaints of that time, but the main issue was that Apple TV didn't do enough, and it did what it did slowly, unreliably, and generally badly.

Over the last 2 1/2 years, Apple has slowly addressed the gripes (most of them). Apple TV is now a pretty good product, and in the fourth quarter of 2008, as the economy was tanking, sales were actually triple those of the fourth quarter of 2007.

The Apple Store's Apple TV page currently shows the product at $229.00 with a 160-GB internal hard drive, the original 40-GB model having been retired. (The fact that the internal drive is so small by today's standards is less of an issue than you might think, because Apple TV easily streams iTunes content that doesn't reside on it.)

In 2007 Mr. Jobs famously (?) spoke of the Apple TV as a "hobby" of the folks at Apple, Inc., not a full-fledged business. The Mac, the iPhone/iPod, the iTunes Store — they're real businesses, Jobs said. Apple TV was something of a household pet in Cupertino. He of course was right about that.

That may change — not real soon, but in the not too distant future. This blogger thinks it will and hopes it does. The key will be that Apple TV is now seen by Apple more as an all-purpose media client, and less as an iPod on steroids.

This paragraph from the Wikipedia article on Apple TV gets at what I mean:

With the "Take Two" software update announced by Steve Jobs at Macworld 2008, Apple TV became capable of acting as a pure stand-alone device, no longer requiring a computer running iTunes on Mac OS X or Windows to stream or sync content to it. Jobs stated, "Apple TV was designed to be an accessory for iTunes and your computer. It was not what people wanted. We learned what people wanted was movies, movies, movies." Users can access the iTunes store directly through Apple TV to purchase movies, music, music videos, and television shows. Customers can also use Apple TV to rent standard or HD-quality movies. Until mid-March 2009, iTunes HD movies could only be purchased from Apple TV.

If your computer goes down, or if iTunes is not running, the only thing you lose is the ability to stream — not sync, but stream — content from it to Apple TV. You can still play your previously synced video, audio, and photo content (as long as it resides on Apple TV's hard drive; if not, Apple TV does want to stream it from iTunes instead). You can still grab content, including HD movies and TV shows, from the iTunes Store directly. You can still play YouTube videos and listen to Internet radio stations (this last being a welcome new feature).

OK, so Apple TV has become a real product, in my eyes at least. Herein, a potpourri of cool stuff about it:

First, there is now a neat iPhone/iPod Touch app called (naturally) Remote (web page here; App Store download link here) that turns your mobile device's touch screen into a way to control an Apple TV. It's free, and it works. It presents the iPhone/iTouch user with an interface very much like the iPod app itself, with the addition of a Control tab that does what Apple TV's Apple Remote does, but more easily and intuitively.

The Control tab in effect turns your touch screen into an Apple TV remote control. You drag your finger along the touch screen, either side-to-side or up and down, to do what the Apple remote (-->) does with its control ring and central Play/Pause/Select button.

The Apple Remote's Menu button, meanwhile, is replaced by a virtual Menu button (<--) in the Remote App — I'll call the app RA for short. The RA > or Exit button brings up various tabs for exiting the Control Tab and accessing "Playlists," an "Artists" list, a "Search" function, and "More": Albums, Audiobooks, Composers, Genres, Movies, Music Videos, Podcasts, Songs, and TV Shows.

In the right-bottom corner is an Options button used to display on your TV Apple TV commands: basically, Start Genius, Add to On-The-Go, Browse Artist, Browse Album, and Cancel.

RA also controls iTunes playback. If (as I do) you have Airport Express units installed on your home network and connected to your home entertainment center(s), RA can tell iTunes to select among those and your computer's own speakers.

In fact, RA seems in some sense to be leveraging the ability of Apple TV to turn itself into an AirTunes device, à la an Airport Express. I don't fully understand what's going on ... but never mind. The important thing is that RA controls Apple TV (or iTunes itself) wirelessly, using WiFi. Unlike with the the infrared Apple Remote, you don't have to be in the same room with Apple TV or a computer running iTunes. That's marvelous. I like to start music playing and wander (with my iPhone) into a different room. RA can direct operations truly remotely, even to the extent of letting me turn up or down the volume when need be, from anywhere in your house.

Another cool thing: RA displays, on the iPhone/iTouch's screen, the cover art of the music you're playing on Apple TV! Cover art also appears next to songs, albums, etc., as you flip through them in RA, looking for something to play.

Here is the take Christopher Breen of Macworld had on RA. (I'm not precisely sure what "Oooh" and "Feh" mean in his lexicon, BTW ... )

* * *

The next item in my Apple TV potpourri is about a neat website, Apple TV Junkie. ATVJ covers Apple TV in depth. I especially like its The More You Know page, where you can learn about such things as:

• Using Third-party Remote Controls With Apple TV
• Using AirTunes With Apple TV
• Apple Remote Pairing
• Streaming Photos From Applications To Your Apple TV
• Streaming Radio On Your Apple TV (Apple TV 3.0 now does this effortlessly.)
  
• Hacking the AppleTV: Get Your Boxee On (Boxee is a gateway to all sorts of online content not officially supported by Apple. To put it on Apple TV requires a "hack" though. The ATVJ article tells you how.)
• Boxee Blog & Boxee On Twitter
• Get The Super Bowl Theatrical Spots In HD On Your Apple TV
• DIY Apple TV Home Media Server
• Movie Rental Video Formats
• Using Chapter Selection In Apple TV
• Removing Menu Items from the Apple TV

Check it out!

VOD Video Quality Comparison

In earlier Video On Demand posts, I've talked about using the Netflix Watch Instantly capability to stream movies and TV shows to your computer or — via a TiVo, a Sony PlayStation 3, or any other "Netflix-ready" device — directly to your HDTV screen. I've also talked about using the Amazon Video On Demand store to rent or purchase videos and then watch them in your computer browser or download them to a TiVo or other "Amazon-ready" device.

I haven't said much yet about the ability to rent or buy videos at the iTunes Store, via the iTunes application on your Mac or PC, as opposed to your web browser. The iTunes Store offers video content for iPhones and iPods, for the Apple TV, and for play on your desktop in iTunes.

I recently rented the 1958 classic horror flick The Fly at Amazon and iTunes and compared the quality of the video with that at Netflix. All these are standard-def versions.

Here is how a particularly useful frame of the movie looks in the Netflix version:




In the iTunes version:




And in the Amazon version:




To see what the differences are, you'll need to click on each of these images to enlarge them in your browser window. The best way to do that is to open each in a new tab in the same browser window, then click on each tab in turn to note the rather obvious differences.

First, rapidly alternate between the Netflix and Amazon versions. They're similar in frame size, but the Netflix covers just a tad more of the original 2.35:1 CinemaScope film frame — compare especially the amount of the grid of the depicted window screen that you can see at the left edge of the picture.

The Netflix image is also sharper. Look at the Roman numeral date MCMLVIII in both images. It's a little more legible in the Netflix than in the Amazon.

Now switch to the iTunes version. The MCMLVIII is downright blurry. The frame is stretched vertically to yield a subtly incorrect picture geometry. The left edge of the picture reveals less of the depicted screen than the Netflix version does — about as much as the Amazon version does. Also, the iTunes version looks duller and darker; the reddish brown background color isn't as vibrant.

In other words, the iTunes image is geared to the low available resolution and nonstandard aspect ratio of an iPhone/iPod screen. The subtle vertical stretching allows the image to use more of the mobile device's limited screen area than would otherwise be the case, given that (nearly) the entire width of the original (extremely wide) film frame is being shown.

Most users probably prefer the slight geometric distortion to having wider black bars at the top and bottom of the iPhone/iPod screen, so this is a compromise that makes some sense. However, if you are watching on a big computer monitor, the soft, stretched image looks pretty bad when compared, in full-screen mode on the same monitor, with the Netflix version — which, after all, is free to anyone with a Netflix-ready TV setup and a standard Netflix account.

Meanwhile, the Amazon version is just a tick inferior to the Netflix version, and far preferable to the iTunes version on any reasonably large screen. If you lack a Netflix-ready setup but have one that is Amazon-ready, you will lose little in terms of video quality (though you will have to pay for each rental or purchase).

Strictly speaking, this comparison applies only to this one movie; it may be that Amazon is better than Netflix for other titles. However, I think it likely that iTunes will be generally unable to match either Netflix or Amazon in terms of video quality, simply because it targets iPhones/iPods first, and bigger, higher-resolution viewscreens second.

An exception: HD content. You can buy or rent certain titles in HD from an Apple TV, for use on the Apple TV. I'll deal with that in a subsequent post.

Another exception: standard-def videos from the iTunes Store, when rented directly from an Apple TV (see this Apple Support document). They can have up to 720x480-pixel widescreen resolution, while the same titles rented from a computer or iPhone/iTouch max out at 640x480. (I rented The Fly from my computer.)

This exception applies only to iTunes Store rentals of videos. iStore video purchases are stuck with 640x480 resolution, no matter what device you use to make the purchase. 720x480 supposedly won't play on an iPhone/iTouch, only on an Apple TV. If you bought a video on your Apple TV and later tried to move it to your iPhone, it wouldn't play ... and Apple doesn't want to deal with the customer complaints when that happens.

An aside for techies:

(The main part of the article is done. If you don't want to be bored by a raft of technical detail, you can stop reading now.)

640x480-pixel anamorphic resolution squeezes a 16:9 widescreen picture into a nominally 4:3 video frame that uses "square" pixels: the individual pixels are exactly as wide as they are tall. The decoder expands the frame again into its original 16:9 aspect ratio, a process that is relatively easy when the pixels are square. Of course, after the pixels are "unsqueezed," they're no longer square, but having square pixels prior to the unsqueezing allows the decoding to be done by a processor of quite limited power, such as is found in an iPhone/iTouch.

720x480-pixel anamorphic widescreen, unsqueezed to 16:9, has non-square pixels both for the input to the decoder and for the output, so the strain on processing capacity is much greater — too great for an iPhone/iTouch. But the Apple TV has (somewhat) greater processing capacity, so 720x480-pixel anamorphic widescreen input works with it.

There are other potential ways in which videos that work on an Apple TV can be incompatible with an iPhone/iTouch. For example, if a video has a bitrate of over 1,500 kbps, iPhone/iTouch won't touch it. iPhone/iTouch can't use videos encoded with bidirectionally predictive frames (B-frames), either. B-frames allow for more compact files and hold down transmitted bitrates. If B-frames were allowed, 1,500 kbps could yield a sharper, more artifact-free image.

But the iPhone/iTouch, because of its tiny, low-resolution screen, can't render any sharper and better images than it does. Plus, higher bitrates require larger memories and faster processors in a decoding device, while B-frames likewise tax the decoding processor and require the frames of displayed video to be held in memory after they have been displayed, "wasting" available memory space. Apple made the compromises that it did in order that the processor speed and memory size of the iPhone/iTouch could be held within reason.

Now, these considerations don't apply at all to Netflix video streaming, for the simple reason that the list of Netflix-ready devices includes no mobile or portable devices.

What about Amazon VOD? Again, Amazon's official list of ways to watch their videos conspicuously fails to mention mobile or portable devices.

In its earlier incarnation as Amazon Unbox, the Amazon VOD service supported Microsoft PlaysForSure portable devices. Those were non-PC devices that were certified by Microsoft to be able to play anything their Windows Media Player app could play on a real computer. PlaysForSure certification was rebranded as "Certified for Windows Vista" in 2007.

Meanwhile, Microsoft had come out with it's own iTouch competitor, the Zune portable media player — and Zune cannot play all PlaysForSure content!

Remind you of anything? Such as: the iPhone/iPod Touch can't play all the content an Apple TV can play (including HD content).

The message here is that it is as yet extremely difficult — nay, impossible — to stream highest-quality video content that "plays for sure" on all manner of devices that turn out to be price-competitive in a competitive, real-world marketplace.

Amazon VOD Rentals

In Amazon's Video On Demand I talked about buying videos from Amazon's VOD store. You can also rent many titles. As this is written, there are 17,327 rental titles and 23,459 titles that can be purchased.

Many of the rentals and to-buy titles are the same. For example, Borat, the 2006 Sacha Baron Cohen hit, costs $2.99 to rent, $5.49 to buy:



When you buy a TV show or movie, it goes permanently into your video library at Amazon.com:



But when you rent, the title is only temporarily in your library until it is downloaded to a device you own that can play it. After the download, you have 30 days to begin playing it on that device. Once you begin watching it, you have 24 hours to finish. When the 24 hours are up, the downloaded copy goes poof.

You can also play the rental on your computer, right in your web browser. Again, you have 24 hours to finish before it vanishes forever.

Here's me renting The Phantom of the Opera (2004). First, I search for "phantom of the opera" at the Amazon VOD store and get:




I click on "The Phantom of the Opera (Rental — 2009)" and see:



(I still have the option to buy the video, as you can see.) At this point I need to already have an Amazon.com account with a credit card or other default payment method on file, and 1-Click ordering enabled. After I click on "24 hour rental with 1-Click $2.99," after a few seconds during which Amazon is processing my order, I see:



I opt to click on the "Your Video Library" link at this point, to see:



Notice that this entry is truly a phantom. Come Dec. 26 at 4:01 PM, if I haven't watched it, it will vanish!

Going back to the "Thank you for your purchase" panel: it gives the options to "Watch Now," "Watch Later," or "Download." You should choose one of these very, very carefully, bearing in mind that "Once you download or start to watch this rental you can't change your viewing choice." That means your choice of a device such as a TiVo to download the rental to is irrevocable. You can't change your mind later and move it to a different device, or decide to play the rental instead in your browser window.

Likewise, if you start playing the rental in your browser, you can't change your mind and download it to your TiVo.

"Watch Now" is what you click to play the rental right in your browser window. "Watch Later" does nothing except leave the rental sitting in Your Video Library, awaiting further disposition. "Download" is the way to initiate a download to your TiVo or other device compatible with Amazon VOD. For purposes of this example, I'll click "Download."

Before I click it, I need to make sure the download is going to go to the right device, so I need to make a selection from the download device drop-down menu:



In this menu I see my two TiVo units, "Living Room TiVo" and "Bedroom," and one Windows computer, "Clone of winxp," running Amazon's Unbox viewer in Windows. (The Unbox software won't run on a Mac.) I want to send my download to my "Living Room TiVo," so I select that, click "Download," and see:



At this point the download has begun. My TiVo box shows a blue LED on its front panel, and if I look in its Now Playing list, I see "The Phantom of the Opera" with a simulated blue LED next to it. The same item appears (redundantly) in the folder representing my "Amazon Video On Demand" group.

I can begin playing the video almost immediately, thanks to the fact that this is a "progressive" download that does not require me to twiddle my thumbs until the whole video has been downloaded.

(If at this juncture I look, in my computer browser, again at my Amazon "Your Video Library," I note that "The Phantom of the Opera" has disappeared from it. Once the rental has begun downloading, that's it: it's no longer in the library.)

Getting back to my Living Room TiVo: whenever I begin playing the rental, before it actually starts I have to wade through a warning to the effect that I'll have just 24 hours to finish watching. When I confirm that starting the 24-hour clock ticking is what I truly intend to do, the video starts playing, just like any other video I have on the TiVo.

If I like, I can temporarily stop playing it — planning to come back to it later — whereupon it acquires a flashing red flag next to its entry in the Now Playing list. This is a warning that at a time 24 hours from when I began watching the rental, it will cease to exist — even if I haven't finished watching it! And sure enough, exactly 24 hours after I first hit Play, the downloaded file disappears from the TiVo.

Amazon's Video On Demand

So far in my Netflix Streaming series, I've talked about the ability to stream Netflix video to your home computers-slash-HDTV screens. Now I'd like to branch out and discuss Amazon Video On Demand.

At Amazon.com's main page you can set the Search drop-down menu to Video On Demand, leave the search box empty, and click Go. If you do, you'll see this. As this post is being written on Nov. 26, 2009, there are 40,691 results, each a movie or TV show that you can rent or buy.

Many titles can be rented or bought — for example, Borat, the 2006 Sacha Baron Cohen hit:



This post covers buying. I'll talk about renting in a subsequent post.

Amazon VOD used to be called Amazon Unbox (Get it? It's a video you can buy, like a DVD or a Blu-ray. But it's not a DVD, so you can't hold it in your hand, it doesn't come in a box, there's no shrink wrap, etc.). Amazon Unbox has been around since Fall 2006; since Fall '08 it's been rebranded Amazon Video on Demand. Where Unbox required you to use a software player that worked only on Windows PCs, Amazon VOD works on PCs and Macs. You don't even need a special player now; a web browser is all you need. (Plus, there is still an Amazon Unbox player that you can use in Windows. Download it here.)

Say you'd like to watch every show in the entire first season of The West Wing. At Amazon's VOD shop, you type "West Wing" into the search box and see various seasons of the late, great NBC political drama at the top of the results:



If you click on Season 1, you'll see (click the image to enlarge):



Here's a close-up of the "Order Now" panel:



Assuming you already have an Amazon account with a credit card and 1-Click buying enabled, purchasing just the first episode for $1.99 is pretty straightforward — it's the default purchase, shown as "Now Playing" in the "Preview" column in the episode list. Scroll down in the list, and you can select other first-season episodes, either singly or as a group, by putting check marks by those you want. Each episode, purchased singly, is $1.99.

But you are interested in the entire season, so you would just click "Buy Season 1 with 1-Click $17.99."

Once you enter your Amazon password and confirm your purchase, all the videos become a permanent part of your online video library at Amazon. To see them listed there, click on "Your Video Library" in the Video On Demand menu bar in your browser window. You'll see a graphic labeled "The West Wing Season 1." Here is mine for Season 2 (I don't own Season 1):



(You can click on the screen image above to enlarge it. The "Your Video Library" tab at upper right is what you clicked on to arrive at this screen in the first place.)

Clicked on, the thumbnail graphic will expand to show all the individual episodes of The West Wing for that particular season:



Clicking on one of the episodes brings up:



You can elect to download the selected episode, or you can watch it right away.

Choosing the download option gives you:



In this case, my download destination is a TiVo video recorder in my "Bedroom." (I'd already downloaded it to my "Living Room TiVo," as the "Locations" entry indicates.)

You can download the videos you buy to various compatible computers and devices in your household, but you have to initiate the download from a computer browser. You can't manipulate your Amazon Video Library from a device such as a TiVo itself.

"Bedroom" is an available download destination for me, since I have already registered that TiVo with Amazon. To do that in my computer browser I went here, then clicked on Refresh list of registered TiVo DVRs. (Go here to confirm what TiVos you have already registered with Amazon, if any.) You can also register the TiVo from the TiVo box itself by selecting "Video on Demand" from the main TiVo menu, selecting "Amazon Video On Demand" from the next menu, and then following the on-screen registration instructions.

Once you have initiated an Amazon VOD download, within a minute or so the destination device will actually begin receiving the video. If the device is a TiVo, a blue LED lights up on its front to indicate that a download is in progress. You can go into its Now Playing list and see the video already listed there. While it is downloading, it will display an imitation of the blue front-panel LED next to its name.

If you want, you can start watching the video even while the download proceeds. This capability of watching an in-progress download is called "progressive download."

If you have a slow Internet connection, it is possible that the progressive download will not keep up with the playback — in which case you will be returned to the TiVo menu screen for the video. You can resume playback of the video at will, but you may have to wait a bit for enough of the video to be transferred to avoid further interruption.


If you prefer, you can bypass downloading the video to a TiVo or other compatible device and just watch it instantly on your computer, in your web browser:



(Click on the image above to see it full size. The grain in the image is a byproduct of my screen capture software and does not appear in the actual video.)

The Adobe Flash Player plugin must be installed in your browser for this to work.

Once the purchased video is in your Amazon VOD library online, you can play it in your browser any time you want, as often as you want.

Remember, watching an Amazon VOD video in your browser starts instantly, since the whole file is not actually downloaded. This is different from a progressive download, for which you may have to wait five minutes or so before beginning to watch the video. That's why if you elect to use the Amazon Unbox player on a Windows PC, you have to wait for enough of the video to be downloaded, before starting to watch.

You don't have to pay extra for each use of the video, whether in a browser window, in the Unbox player, or on a device like a TiVo. You can also re-download it at any time for free; if you delete it from Unbox or your TiVo you can get it back at will. This is the advantage of buying rather than renting.

However, if you will only be watching a video once or twice, and if Amazon offers it for rental rather than purchase, renting can save you money. Renting will be the topic of my next post ...

Of NeRDs and Silverlight

My last post, Instant Netflix on PS3 and TiVo, was about how you can stream movies and TV shows directly from Netflix, via the Internet, to a home TV or computer screen. You don't even need to wait for a DVD in the mail.

Here I'd like to begin going into more depth about how Netflix accomplishes this magic. I'll discuss various topics, plus I'll give links to where you can find out more. Fair warning: I don't guarantee that all of my information is perfectly accurate or complete. I'll try to do the best I can.


You can stream Netflix content onto your computer via a Web browser, or you can stream it to a TV screen through any of several home entertainment devices: certain recent-model TVs that allow Internet access; certain set-top boxes such as TiVo DVRs; certain Blu-ray players that can get online using BD-Live connectivity; and certain game consoles like the Microsoft Xbox 360 and Sony PlayStation 3. These non-computer devices that can stream Netflix are what Netflix calls Netflix-Ready Devices; I call them "NeRDs."

If you're using a computer, the magic formula enlists either Firefox or Safari, web browsers compatible with Silverlight, a plugin from Microsoft that plays video content from Netflix right in a browser window. Let's say you want to watch WALL-E, the 2008 Disney-Pixar hit. You encounter a WALL-E thumbnail at Netflix.com that has a white-on-blue "Play" button below it, or you pull up the dedicated page for the film and see a similar "Play on Computer" button. You click once and watch as a video player appears in your browser window.

But instead of seeing the movie, you get a warning that you need to download and install the software called Silverlight. Your browser offers to do the download, after which you use standard procedures to install it as a browser plugin. It all happens quickly and painlessly. Then you restart your browser and try WALL-E again, and after a few seconds of preliminaries — "Connecting to the Netflix movie server" / "Downloading movie information" / "Determining your video quality" / "Buffering" / "Acquiring content license" — the movie begins, all thanks to Silverlight!

What about those non-computer NeRDs? Home entertainment devices that can stream Netflix content don't use web browsers. They incorporate firmware (aka "system software") that, in turn, incorporates the same functionality as Silverlight. (For all I know, it is Silverlight in a different form ... but it isn't in the form of a browser plugin.)

An exception is the Sony PlayStation game console-cum-Blu-ray player, which won't get firmware that incorporates Silverlight functionality until late 2010. For now, that functionality comes on a Blu-ray disc that you slide into the PS3 each time you want to stream Netflix.


Silverlight (or its NeRD clones) enables Netflix's movie servers to select a bitrate that your network connection to the Netflix server can handle. Each movie is encoded several times, at various bitrates. The higher the bitrate, the better the picture and sound. But if the Internet connection can't keep up with the bitrate that is originally selected, the server won't get "return receipts" (technical term: acknowledgments) back from Silverlight in time. The server can then switch seamlessly to a lower bitrate, and Silverlight is capable of hiding what is going on from the user's eyes and ears.

So, during the "Determining your video quality" preliminary stage, the server cooperates with Silverlight to measure your network speed. Then it selects a bitrate that fits that speed.

Even so, sometimes acknowledgments begin arriving back late, or not at all ... in which case the server assumes some of the information it sends out in the form of message packets is getting lost. It arranges with Silverlight to start using smaller packets. The smaller the packet, the less the information that has to be retransmitted when a packet is lost. Cutting down the packet size saves retransmission overhead and allows the server to avoid dropping down to a lower bitrate. Ideally, playback quality remains the same.

If necessary, though, the server can go so far as to lower the bitrate. If the video is standard definition, 1,500 kbps (the highest SD bitrate that Netflix uses) can drop to 1,000 kbps, 500 kbps, or even as low as 375 kbps. (I'm getting this, by the way, from an article in The Netflix Blog called "Encoding for Streaming.")

When I watch an SD movie using my PlayStation 3, the PS3 lets me display the instantaneous bitrate on the TV screen. I find that the instantaneous bitrate varies widely. Frequently it goes well above 2,000 kbps. When there is little motion in the scene though, the bitrate drops well below 1,000 kbps. In other words, the instantaneous bitrate is variable. This is called "variable bitrate encoding," or VBR. The average bitrate, I assume, is the advertised 1,500 kbps.


Sometimes the speed of the network connection drops enough to cause problems if the original average bitrate isn't likewise dropped down to a lower bitrate.

In the VC-1 Advanced Profile (VC1AP) encoding that Netflix uses, according to the blog post, "each GOP [group-of-pictures; a "picture" is an individual "video frame"] header includes frame size and resolution, which allows [Netflix servers] to assemble a stream on the fly from different bitrate encodes as your broadband bandwidth fluctuates."

This happens without the user being aware of it, because Silverlight recognizes on-the-fly changes in bitrate by inspecting the parameters in the GOP headers, and it accommodates those changes automatically.

The result can, however, be a drop in perceived video quality. Lower average bitrates can mean more digital compression artifacts, hence messier-looking images. Or there can be fewer video frames per second in the lower-bitrate encode, so motion gets choppy.

However, the swings in instantaneous bitrate due to VBR encoding are a different story. They happen in response to the changing complexity of the moving image, just as they do on a DVD. In order for the viewer to perceive unchanging video quality, more bits are needed to encode highly complex images having a lot of fast motion, while fewer bits are needed for simple, static images.

When Netflix uses a 1,500-kbps encode, it is implicit that the instantaneous bitrate will sometimes be much higher than 1,500 kbps — and so the network connection has to be able to deliver more kilobits per second than the average bitrate implies. In other words, the speed of the connection must be fast enough to allow for the occasionally high overhead of VBR encoding.


What about high-definition encodes? At the time the Netflix blog article was written (Nov. 6, 2008) there were some 400 HD streams available. The article says HD is encoded in VC1AP at 3,800 kbps and again at 2,600 kbps. The video resolution in both cases is 720p, which means each video frame, with its 16:9 widescreen aspect ratio, is made up of 720 rows of 1,280 pixels per row.

This is not "Full HD" 1080p encoding, such as is found on Blu-ray, or even 1080i, each of which would require each frame to contain 1,080 rows x 1,920 pixels.

There are 24 frames of 720p video per second for material transferred from film, mimicking the frame rate of film itself. Shot-to-video HD material is at 30 frames per second (25 fps for video material shot in the British PAL standard). Again, this is not as good as Blu-ray, which uses 60 fps for HD video material shot in the U.S. This type of encoding is referred to as 1080p60. Netflix uses 720p30 (or 720p24 for film-based material).

Netflix says it believes "using 1080p60 would require a bitrate out of reach for most domestic broadband today. We believe Moore's law will drive home broadband higher and higher enabling full 1080p60 encodes in a few years."


Another article from the Netflix blog, "Netflix Trying for Consistent Excellence on Streaming," gives more information about what goes on behind the scenes. Netflix streams use servers scattered around the country to avoid congested Internet "backbone" lines. The servers are organized into "content delivery networks" (CDNs). The CDN approach groups servers in regions that serve nearby users. The nodes of the CDNs cooperate with each other to satisfy requests for content by nearby users.

If several users are watching, say, WALL-E at 1,500 kbps, one particular server of one particular CDN is active for all of them. If that server encounters major congestion between itself and any particular user, that one user may develop problems with playback, or lowered video quality. Other WALL-E watchers may see no problems whatever.

In fact, Netflix says, the combination of server and network path may vary depending on what type of device the user is using. "Accordingly," the article says, "[individual] customers may see better performance on [an] Xbox than [on] their PC, or vice-versa."


Netflix's strategy is to keep as many users satisfied as possible, as much of the time as possible, while giving them the best possible video and audio quality. In addition, Netflix wants playback to begin as quickly as possible after the user has initiated it.

This sounds good ... but some users have complained that they typically have slow network connections and never get top-quality results. These users have asked to be able to pre-buffer content using the best-quality encode at the highest available bitrate. They say they don't mind if the start of playback is delayed until a hefty portion of the content — or all of it — has already been buffered.

So far, though, Netflix has not built such a pre-buffering option into Silverlight.

Instant Netflix on PS3 and TiVo

Got Netflix? You and 11.1 million others in the U.S., as of 9/30/09; Netflix is huge. Unless yours is a so-called "limited" account, you have an Instant Queue (IQ) you can load up with movies that you can then watch instantly to your heart's content. You can do that on a computer. You can also do it on your TV screen, via a TiVo or other set-top-box, a game console such as a Sony PlayStation 3 or a Microsoft Xbox 360, certain models of Blu-ray player (typically, recent ones with BD-Live capability), or even certain TVs that have Internet connections. All these so-called Netflix-ready devices (NeRDs?) connect to the Internet via WiFi, or via an Ethernet cable if you use one.

It's taken me a while to catch on to Netflix streaming. I ignored it when, some time ago, my TiVo #1 began carrying Netflix (see this press release). Then, the other day, I was fiddling with my Sony PlayStation 3, which sits in my living room below my TiVo #2 unit and, just like that TiVo, feeds signals into my favorite flat panel TV. After a firmware upgrade, the PS3 alerted me that I could now use it to stream Netflix (see this press release). Seemingly, all I had to do was use the PS3's built-in browser and visit Netflix.com to begin streaming movies from my Netflix IQ. So I did.

Actually, the browser just let me link to Netflix to ask for an Instant Streaming Blu-ray Disc for the PS3. The disc had to be mailed to me. (I couldn't believe the software can't be downloaded!) Also, you'll need to be sure you've upgraded your PS3's firmware to version 3.01 or later, to allow the Netflix software to work.

Once you get the disc — which you keep and never mail back — you insert it in your PS3 and see an activation code come up on your TV screen. You have to run to your computer to enter that five-character code into this web page, because with the disc in the PS3, the PS3 can't use its own browser, or any of its normal functions(!). With the disc inserted, the PS3 becomes a dedicated Netflix streamer, until you eject the disc or use the Back button on the PS3's remote to idle the disc.

The dedication of the PS3 to Netflix streaming while the disc is active, by the way, is why you need to keep reinserting the disc each time you want to watch Netflix on the PS3. Netflix claims it used an external disc as the quickest and cheapest way to get streaming capability to the PS3, but rumors abound that the real reason was that the company's exclusivity arrangement with Microsoft (whose Xbox 360 already streamed Netflix) had to be worked around — technically — by keeping the Netflix interface off the PS3's Cross Media Bar (XMB). The XMB is the fancy menu system the PS3 uses to allow the user to navigate among the game console's various functions. The Xbox 360's equivalent is the Dashboard. Netflix seems to have felt constrained to keep its streaming function off the PS3's version of the Dashboard.

This is apparently a temporary situation. By late 2010, Netflix expects its software to be embedded in a new release of the PS3 firmware.

After you activate your shiny new disc on your PS3, you'll immediately see your IQ on the TV screen and can navigate to and begin watching any item in the queue. Play begins pretty quickly. It's not at all choppy or pixellated. The video and audio are, I find, basically of DVD quality. Netflix says here that it "automatically chooses the video quality to give you the best image possible based on the speed of your Internet connection. The faster your Internet connection, the higher the quality that we can deliver to you."

Did I mention that watching movies from your IQ is free? It's included with the cost of a regular (i.e., non-"limited") Netflix account! With Netflix, you don't have to pay extra for video-on-demand. Take that, cable companies!

Also, the PS3 Netflix application's attractive and easy-to-use interface lets you locate and add stuff to your Instant Queue, using just your PS3 remote. The IQ updates right away, so you can begin watching new items immediately.

But what you can't do is type in, say, "Kubrick," to see all the available films of Stanley Kubrick. You'll need to use your computer for that sort of thing. Or try the Instantwatcher iPhone app, which lets you manage your Instant Queue from an iPhone or iPod Touch:



There is also an Instantwatcher web site, which you may want to check out.


It gets better. My two TiVo units (as I'd been so blind to) also stream Netflix.

The user interface is different: it's TiVo-like, which has its good points and bad. A good point is that you can opt to have the Netflix IQ show up as a folder (appropriately, red) in your Now Playing list. The folder's individual titles can be sorted alphabetically. If you add (say) the entire first season of The Office to your IQ, it shows up as a subfolder within that folder.

A bad point is that there seems to be no way to add items to the IQ from the TiVo, as is easy to do from the PS3. (But once you add an item via the PS3, you can watch it right away on the TiVo, if you prefer. Or you can just watch it right on the PS3.)


It gets better still. Some of the content that you can stream from Netflix is in HD!

HD streaming works seemingly identically on my two TiVo units and on my PS3. On all of them, I seem to be finding that the resolution is always 720p, never 1080i/p, even on TV shows like The Office that are broadcast in 1080i. I guess the 720p limitation is a compromise to allow Internet streaming of HD content at all. Or it may be that if I had a really extremely fast Internet connection, I'd see 1080i — who knows? 720p looks great, anyway, so I'm not complaining.

You can get another blogger's take on HD content streaming from Netflix to the PS3 here.


Speaking of content, there are today some 17,000 titles at Netflix that can be streamed instantly. That may seem like a lot, until you stop to consider that Netflix has over 100,000 DVD titles (not to mention Blu-rays). It looks as if few if any of the very latest movie releases make it to Netflix streaming until they're past their period of hottest popularity.

That makes sense. Netflix streaming is essentially a free feature — for those who already pay for an account. Why should Netflix give away its most sought after titles? Plus, the movie studios probably wouldn't care much for it. In fact, I'd bet money that it won't be long until Netflix starts charging to stream stuff, either some or all of it.

Netflix says more on-demand titles arrive "every day," and I suppose one reason why it takes a while for new releases to appear may be that they have to be specially rendered into the necessary video format or formats. For example, if The Office is in 1080p on Blu-ray, it has to be converted to 720p for Netflix. If, as I suspect, there are different formats for different connection speeds, that only compounds the problem.

See other posts in my Netflix Streaming series for more ...

BD-Java Features of Blu-ray Discs and Players

Thinking about a Blu-ray player for your next home video purchase? Good choice, but keep in mind ...

Once you decide to go Blu-ray, you are confronted with a welter of confusing features that some players and discs offer, and others do not. For instance, if you look at this list of available Blu-ray Discs at Blu-rayStats.com (click on the image below to see the list)



you see a table listing all the Blu-ray Discs yet issued, some 1,552 as of this writing. There are columns labeled "BD Java," "Pic in Pic," "Bonus View," and "BD Live." What do these mean?

In plain language, these have to do with whether a Blu-ray player, playing a Blu-ray Disc as opposed to a DVD, can do certain things: provide interactive menus that "pop up" over disc content; handle "picture-in-picture" video and audio content that plays over top of "regular" disc content; and/or access additional disc content that resides on the Internet, not on the disc.

All of these are optional disc features that, in order to work, have to be supported by capabilities in the player. Not all players support all the features, and not all discs contain all the features. Many Blu-ray Discs have none of these features.

In general, the later the date a model of Blu-ray player was introduced, the more likely it is that all of these disc features are supported. However, some older players can have their onboard firmware updated to support disc features not originally supported at the time the model was introduced ... as long as those players have all the necessary hardware.

Here's a rundown on the features and the computer language which supports them:

BD-Java: All of these features utilize the BD-Java computer language that is geared especially to Blu-ray. BD-Java is also called BD-J, or Blu-ray Disc Java. Basically, it's a programming language that all Blu-ray players support, in some version. Blu-ray players are actually (in addition to being able to play Blu-ray Discs) a kind of computer that runs BD-Java, and Blu-ray discs optionally take advantage of that.

Blu-ray discs that take advantage of BD-Java and the features it supports have to be "authored in BD-Java," which means they possess a different file structure on the disc than they would if they were just "ordinary" Blu-ray Discs that are not authored in BD-Java. Disc "authoring" is, simply, how the various pieces of information that are recorded on the disc are put together by the creators of the disc. Blu-ray discs are authored using files. Much like files on your computer, these files exist in a folder hierarchy on the disc. Blu-ray players, needless to say, hide the file structure/folder hierarchy from user view.

On the Blu-rayStats.com page mentioned above, discs that are authored in BD-Java are shown with a "Yes" under BD Java.

Interactive "pop-up" menus: BD-Java disc authoring opens the door to several user capabilities. One is simply the ability for a disc to provide interactive "pop-up" menus. Blu-ray Discs that are not authored in BD-Java must get by with "dumb" menus like those on DVDs, which really aren't "smart" or interactive and can't pop up while the disc continues to play. But Java-authored Blu-ray Discs can have truly interactive pop-up menus that use the BD-Java computer language and file structure.

Here is an example of a pop-up menu:



Not all Java-authored discs provide pop-up menus. Just because a disc is authored in BD-Java does not mean pop-up menus exist on the disc.

Nice as interactive pop-up menus are, most or all Blu-ray Discs which use pop-up menus unfortunately do not allow a Blu-ray Disc player to automatically resume a movie from any arbitrary point in the middle of the movie where the movie was stopped. This is a feature we are used to on DVDs and DVD players, and Blu-ray players also support it on those Blu-ray Discs that don't have pop-up menus. But there is something about discs with BD-Java pop-up menus that prevents this feature from working.

Blu-ray profiles: Every Blu-ray player supports BD-Java — and thus, at a minimum, pop-up menus — but there are three different levels, or "profiles," at which BD-Java support may be included in a playes, depending on when the player model was introduced.

Profile 1.0: The first level of BD-Java support is called Profile 1.0. All Blu-ray players, however early they were introduced, support Profile 1.0 of BD-Java, which is what allows discs to have pop-up menus. (Again, not all discs in fact have interactive pop-up menus, but all players support them if they are in fact present on a disc.)

Profile 1.1: The second level of BD-Java support is Profile 1.1, which has also been dubbed "Bonus View" or "Final Standard Profile" (though it isn't actually final). Profile 1.1 does what Profile 1.0 does — mainly, pop-up menus — plus adding the ability to play a "picture in picture" (PIP) as a secondary audio-video stream from a Blu-ray Disc that is programmed to show one.

If you can see a small window of (say) video commentary on the TV screen, where a director or actor talks about a scene being shown in the background, you may be seeing Bonus View in action. Here is an example from a German Blu-ray title, Neues vom Wixxer:



Blu-ray Discs that offer Bonus View are shown on the Blu-rayStats.com page with a "Yes" in the Bonus View column. If you invoke the "Has Bonus View" filter, you will see just the releases with Bonus View — 106 as of this writing. You can play these releases on Profile 1.0 players, but you can't access the Bonus View content.

Keep in mind that some Blu-ray Discs have been issued with PIP implemented by means of a second whole copy of the movie that is recorded separately on the disc with an inset audio-video program over top of the main picture. This is not Bonus View.

Bonus View-compatible players need to have additional hardware, above and beyond that required for Profile 1.0 players: 256 MB of "local storage" — a.k.a. "persistent storage" — such as flash memory or a hard drive (none was required for Profile 1.0); plus secondary video and audio decoders. If a Profile 1.0 player lacks these extra items, it can't be upgraded to Profile 1.1 via a simple firmware upgrade.

Blu-ray Discs that offer picture-in-picture content are shown separately on the Blu-rayStats.com page with a "Yes" in the Pic in Pic column. If you employ the "Has Bonus View" filter on that page, you can see that all Bonus View discs are "Pic in Pic" discs. However, there are some "Pic in Pic" discs that don't Bonus View ... and some that don't even use BD-Java.

For example, the movie "Blow" is shown as "Pic in Pic," but not as either "BD-Java" or "Bonus View." These discs don't use BD-Java, and they implement PIP with a second whole copy of the movie.

The movie "The Contract" is shown as having "Pic in Pic" and "Bonus View," but not as having "BD Java." That makes questionable sense. To the best of my understanding, Bonus View requires BD-Java.

Profile 2.0: This is the third (and supposedly final) level of BD-Java support in Blu-ray players — for videos, that is; there is a Profile 3.0 in the works for BD-Audio use.

To the capabilities of Profile 1.1/Bonus View/Final Standard Profile and of Profile 1.0, Profile 2.0 adds an Internet connection via an Ethernet port and/or via a wireless 802.11 (WiFi) adapter. This connection allows players to honor certain Blu-ray Disc titles' ability to access online content. The bonus material on the disc is augmented with additional bonus material from the Internet. This Internet-based extra content is "live" — it can change — and so Profile 2.0 is called "BD-Live."

Players that support Profile 2.0/BD-Live add extra "persistent storage," above and beyond that needed for Profile 1.1, with a minimum of 1 GB of storage being present to hold downloaded content and the like.

All the features of Profile 1.1 and Profile 1.0 are supported by Profile 2.0.

Again, a great many Blu-ray Discs don't make use of Profile 2.0/BD-Live. The ones that do are listed in Blu-rayStats.com with a "Yes" under BD Live. As of this writing only 177 are shown, when you invoke the "Has BD Live" filter ... and if you also invoke "Has Bonus View," there are only (as of this moment) 51 Blu-ray Discs released in the U.S. that use both.

Because Profile 2.0/BD-Live requires additional hardware beyond Profile 1.1/Bonus View/Final Standard Profile, unless that hardware happened to be included on a Profile 1.1/Profile 1.0 player, that player cannot be upgraded to Profile 2.0 via a firmware upgrade.

Confusingly, some earlier players that don't support Profile 2.0 do have an Ethernet port. These are strictly for firmware updates and can't be used to access downloadable BD-Live content. Hence, there is no way to upgrade these players to Profile 2.0. (What could they have been thinking?)

Can You Upgrade Blu-ray Discs?

Blu-ray discs have to be authored in BD-Java by their creators and programmed to use interactive pop-up menus and/or Bonus View picture-in-picture content and/or BD-Live content, if those capabilities are to be supported by the disc. (In theory, a disc could be authored with BD-Java and have none of these features.)

Since Blu-ray Discs are read-only, there is no way to "upgrade" a disc to use these features — even if the disc is authored in BD-Java — once the disc is made and is in the customer's hands. Accordingly, a title that was released without BD-Live capability may wind up being re-released in the future with it. The customer who wants to take advantage of BD-Live would have to buy the title a second time, assuming it is ever re-released. (An exception: if a disc includes BD-Live capability in the first place, the online content that it can access can be changed or amplified over time.)

Bookmarks: There is another BD-Java capability that is of interest: the ability for the user to create "bookmarks" that allow any point in a movie that is bookmarked by the user to be returned to at will. A bookmark is sort of like a home-brew chapter stop that the user creates on the fly, usually by pressing a button on the remote, then uses to select where playback of a program moves to or begins the next time the disc is used. A bookmark is sometimes called a "personal scene selection."

I have been unable to discover whether bookmarks officially require any particular BD-Java profile, but they do require that the bookmark capability, which is programmed in BD-Java, be explicitly included on a particular Bu-ray Disc. Hence, only certain discs support bookmarks.

However, I do know that disc-based bookmarks are saved by the Blu-ray player on its "local storage" — which makes sense, since the disc itself is read-only. Since Profile 1.0 does not require the player to have local storage, I assume that bookmarks need a player with Profile 1.1 or Profile 2.0. However, since Profile 2.0 is basically nothing more than the addition of BD-Live online content to Profile 1.1, I assume that all you really need to use disc-based bookmarks is a player with Profile 1.1.

For discs that use "pop-up" menus and accordingly cannot automatically resume playing a stopped disc at the point at which is was stopped, creating and later returning to a bookmark can be something of a workaround to the no-resume-play problem.

Finally, some questions that you may be asking are these:

Why this nasty, arbitrary, incremental approach to advanced disc-and-player features in the Blu-ray world?

Why did the potentates of Blu-ray produce so may player models that can't be upgraded, though they knew from day one what the eventual capabilities of players (and discs) would be?

Why are there, even now, so few Blu-ray Disc releases that take advantage of (any or all of) interactive pop-up menus, Bonus View content, and BD-Live content?

I don't claim to know all the answers, but here are some semi-educated guesses. First of all, for whatever reason, Blu-ray's competitor format HD DVD made it to market, with players and discs, earlier than Blu-ray. Blu-ray was playing catch-up.

And it knew catching up was hopeless if it waited until BD-Java disc authoring and the full set of features it would one day support were mature, fully developed technologies.

So the viziers of Blu-ray rushed their product to market with whatever capabilities were ready to go.

Meanwhile, HD DVD was designed in a dissimilar way, with no full-scale equivalent to BD-Java. So HD DVD could be there "firstest with the mostest," with features like picture-in-picture built in from the get-go.

To add injury to insult, rushing Blu-ray to market meant that the first disc releases could not be on dual-layer discs, since the facilities for manufacturing those discs weren't ready. Hence, single-layer releases were the norm. That's since been corrected. Plus, the advanced video codecs "VC-1" and "AVC" weren't yet supported by disc-mastering facilities, so MPEG-2 (the codec used on DVDs) had to be used. That, too, is ancient history. But for a while, the fact that MPEG-2 doesn't compress video nearly as compactly as VC-1 and AVC (also called MPEG4/h.264) meant that it was hard to shoehorn a movie into a single-layer disc without over-compressing it, harming visual quality. There were a lot of complaints that Blu-ray Discs didn't look as good as HD DVDs.

All in all, it's a wonder the Blu-ray format survived at all. But it did, and today it's alone on the battlefield. HD DVD is dead.

Unfortunately, though, the contortions Blu-ray had to go through to avoid having to run up a white flag have left us with a legacy of confusing profiles and player-and-disc features to contend with, as we try to be smart Blu-ray consumers.




For more on the different Blu-ray profiles, see http://news.cnet.com/8301-17938_105-9808376-1.html. For information about the way content on Blu-ray Discs is organized, "The Authoritative Blu-ray Disc (BD) FAQ" at http://www.emedialive.com/articles/readarticle.aspx?articleid=11392.