Content encoding: MPG:

An acronym for Motion Picture Experts Group (why is this not surprising?), this format was adopted as ISO11172. Across the board, MPGs carry a respectable load of metadata (mostly chiron-type info but way more of it). They are tough to edit which offers some degree of protection and they offer high quality audio and video.

MPEG-2 is the only viable choice at this time.

Methods or types of web enabled DVDs:

Other people talk of split DVDs, enhanced, bonus, etc., but everybody else is making up words, why can't I?

1. Multilayered-separate content for different players as in our discussion of DVD10-18, we'll discuss these in more detail later in Physical Disk Solutions.
2. Bridged-content exists in different formats on the same physical disk layer with provision for how platforms identify appropriate content. This is the one to go with in the event of compatibility issues.
3. Bonus content-a DVD-V that has some ROM files on it as an afterthought.
4. Augmented-DVD-V presentation that has certain integrated online functionality (bulding upon the limited functionality contained in the DVD specification.

Control:

To call number 2 above a bridge is kind of ludicrous. We have more of a chasm than a bridge. But similar to the UDF bridge in ISSO9660, there are certain control points we can take advantage of. To understand these, you must understand that:

1. Our ability to control what gets played by what depends as much on the platform ignoring "other" data as it does looking for "it's" data.
2. Our ability to play anything at all depends upon us providing content in a form a given platform likes. For example, set-top DVD players look for and attempt to parse contents of a video_ts folder in UDF and ignore all else.

These control points weren't meant to do what we want to do, but taken together, they form a series of "bridges" that we can construct to effect control to a degree.

1. UDF Bridge. Specified in ISO9660, this contains an identifier recognizable to certain OSs
2. Autolaunch. A setting on the disk itself. By setting this to 0, the disk will be treated as ROM by computer OSs (both PC and Mac).
3. Order of content. While DVD-V specifies that the video_ts folder appear first on the disk, many set-tops reportedly ignore all content not in video_ts. This option can effect what environment is used for computer DVD play.
4. Multilayer. Introduced in the preceding, we'll amply discuss these in the following. Multilayers would effect control on a very basic level.
5. Obfuscation. A hypothesis of mine. We should be able to conceal certain content from certain platforms by rendering it unrecognizable to the target platform yet useable by others. Having Director pull VOB content from a folder called video_Trevor for example.
6. User action. You know I'm getting desperate when I talk about prompting user action but it's a historical control point. Steve suggests that DVD-V content could be preceded by a screen instructing computer users to run the ROM version or computer users to run a platform-specific version.

Regardless of such controls and workarounds, all of the preceding has limited web-enabled DVD development in the following ways:

1.Development & production are necessarily divided between DVDROM and DVD-V considerations
2. Vendors and manufacturers have not consistently adopted specifications or technologies. We have no way of knowing what our product will look like on future consumer electronic products.
3. It's a hell of a crude way to manipulate multimedia. If there was only a "preferred device" hierarchical-setting in the UDF spec that provided unassigned IDs for future use we'd be golden. Ha!

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