Douglas Crockford




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Pronouns: pe/per


March 2006

Coded Anti-Piracy Code

Coded Anti-Piracy Code, aka CAP Code, aka CRAP Code, is a form of watermarking that is intended to thwart the use of camcorders in capturing theatrical movies. Unique codes are burned into a print. The code is visible as a pattern of reddish brown dots. The theory is that pirated software can be traced back to the theatre where the print was shown. It is not clear how this would be effective in deterring street vendors from selling DVDs that are already obviously illegal.

The dots have been getting bigger and uglier. This may be to keep the dots from being washed out by the lossiness of MPEG compression. But I think it is really a way that Hollywood shows its contempt for the audience. Their attitude is that the public does not deserve to see clean prints because we are all just a bunch of thieves.

If Hollywood does not take care to improve the quality of the theatre experience, its future will be making loss leaders for Walmart.

HDTV Geometry

When HDTV was designed in 1993 by the so-called Grand Alliance, they had to choose between two proposals that had already been kicking around for 5 or 10 years. The biggest difference between them was the Interlace Issue. The Interlacers saw that television had always been interlaced. Interlacing (the transmission of only alternate lines) cuts a number of cost components in half. It was a long-proven compression technique.

On the other side were the Progressives. The Progressives saw that interlacing didn't make sense in a digital system. Compression is better done in the digital domain. Interlacing adds temporal artifacts, and can increase the cost and complexity of image processing.

There were some things that the Progressives and Interlacers could agree on: The aspect ratio should be 16x9. The number of pixels should be no more than 220. The reason for the megapixel constraint was that computer memory at those sizes was still expensive, so they wanted to make the most efficient use of the chips that were available at the time. Since then, however, memory costs have come down spectacularly. It is now reasonable to put a gigabyte in a low-end PC. The Grand Alliance did not predict how long HDTV would take to come to market, so they optimized the architecture for factors which are no longer relevant.

Using round numbers, the Progressives computed the size of the megapixel 16x9 display to be 1280x720. This is sometimes called 720p, the p meaning progressive.

The Interlacers did the math differently. Since interlacing only transmits alternate lines, they only had to include half of the lines in their calculations. That worked out to 1920x540. This is sometimes called 1080i, the i meaning interlace. Some Progressives think it should have been called 540i.

There is now growing demand for another format, 1080p. This is perhaps the single format that should have been in place from the beginning. It is possible to buy 1080p sets now, even though there is no source for 1080p programming to show on it.

Digital Film Geometry

Through the Golden Age, the aspect ratio of the movies was 4:3. When television came around, it took the same 4:3 because that seemed to be the standard shape. Hollywood saw its doom in television, so it invested in changes like better sound and wider pictures. There are lots of film formats, but the most common was 1.85:1.

When NHK began experimenting with HiVision, they chose 5:3 because of its classic proportions. When the Grand Alliance considered HDTV, they went with 16:9, even though it is a little narrower than the common film format.

When the Digital Film Initiative began looking at digital film standards, they looked at the new HDTV standards and then did something different. Like the Grand Alliance, they couldn't agree on resolution, and so chose two:

The lesser one is similar to 1080p, which is 1920x1080. The film format isĀ 128 silly pixels wider.

The television guys count resolution vertically: 720p, 10080i. The film guys count horizontally, so the two formats are called 2K and 4K, respectively.

So digital film and digital video could have been based on a common format, but they aren't. And if you just bought a 1080p system because you wanted the very best there is, be aware that compared to 4K, your set looks like crap.

Ah wish ah knew how to quit yew, Wal-Mart

The Rev. Donald E. Wildmon took on the big, Satan-based TV shows like Donahue, Wonder Years, Seinfeld, Major Dad, Roseanne, Murphy Brown, L.A. Law, Northern Exposure, and Quantum Leap. Thanks at least in part to his tireless efforts, every one of those shows has been canceled.

But now Wildmon and his American Family Association is facing its biggest challenge. They have launched a letter writing campaign which is intended to stop Wal-Mart from selling the DVD of Brokeback Mountain. Wal-Mart already carries the Brokeback Mountain novel in paperback ($8.70), but Wildmon isn't much of a reader. He is more worried about the DVD, which hits Wal-Mart shelves on 2006-04-04.

The stakes couldn't be higher. Evangelicals going into their local Wal-Mart to buy a few gallons of pickles might be tempted to pick up a copy of the Oscar-winning DVD ($16.87). They will then take it home, watch it, and turn gay.

Then the Rapture comes, and they will not be taken to meet with Jesus in the air. Instead they will be left behind with the rest of us to be oppressed by the Antichrist and ultimately cast into the lake of fire.

But it might be possible that things won't turn out that way. It might be possible that it is only a movie.

HD Discs

At long last, the new HD disk formats are coming to market. The main contenders are Toshiba's HD-DVD and Sony's BluRay. But there are lots of dark horses, too. There is VCDHD (Versatile Compact Disc High Density) from Ukraine, EVD (Enhanced Versatile Disc) from China, FVD (Forward Versatile Disc) from Taiwan, and the holo systems, Tapestry from InPhase and my favorite, HVD (Holographic Versatile Disc) from Optware.

Which one should you buy? That's easy: None of the above. It is not clear yet that any of the dark horses will get to the mass market. And the market will not sustain the two leaders. At least one of them must die before the market goes mass. If you buy one this year, there is a very good chance that that format will be abandoned in a year or two. Also, HD-DVD and BluRay have horrible DRM systems. I think ultimately the market will demand that DRM restrictions be made reasonable. Hold off buying until that correction happens.

In the meantime, the EDTV delivered by DVD looks pretty good for now.