The title menu of the supplied DVD project is a still menu. This attribute is shown as an infinite cell still time with a value of 255 at offset byte 240 in the above program chain that displays the title menu. A cell having a still time of 255 is displayed as a still picture. Most static DVD menu is designed as a still cell so that the user can select from one of the menu items overlaid on the displaying still picture. The video object unit (VOBU) that has all required video and audio information and button commands is stored at sectors 0 through 50. To help identify and locate this video object unit quickly, the VOB id (1) and cell id (1) for this VOBU can be used while reading the contents of the VIDEO_TS.IFO file.

All DVD button commands associated with a display menu or a particular menu item can be viewed with the freeware tool VOBEdit. This tool is capable of many more DVD stream extraction functions. This guide takes advantage of only the browsing capability of button commands provided by this freeware tool. We now launch VOBEdit and locate the file VIDEO_TS.VOB that contains navigation commands for the items on the title menu. In some cases, VOBEdit may not interpret certain commands and display them as NOP (No Operation).

We select the button check box as shown in the following screen shot to show the button commands present in the navigation packets. We should note that the VOB id is 1 for the button commands associated with the title menu as indicated in the above program chain. The following button commands are defined for each menu item in the title menu. The DVD specifications allow only one virtual command per button (menu item).

1) JumpTT 1 (Jump to title 1)
2) JumpTT 2 (Jump to title 2)
3) JumpSS VTS_1, AngleMenu (Jump to the angle menu of the video title set)
4) RSM (Resume playback).

The DVD Advanced Data Structures and Virtual Commands By Example 2.1 is now available in Adobe Acrobat PDF ebook format.

The ebook version offers these immediate benefits:
Having more detailed information than on the web pages.
Help you mastering the data architecture of commercial DVD titles in a very short time.
Better use of authoring products such as Sonic Scenarist, Adobe Encore, DVD-Lab, IFOEdit, etc.

Detailed knowledge of typical DVD menu navigation commands.
A 10-MB 100% DVD-compliant sample project to download.
Ability to verify and edit data structure fields using IFOEdit with a sample DVD title.

Browse DVD menu button commands using the included freeware tool VOBEdit.
Use GPRM registers with DVD virtual commands JumpTT and JumpSS.
Conversion of DVD color from YCrCb to RGB plus a free copy of DVD-Color 2.16.

30-day email technical support.
Acquire the required technical background to write DVD applications and a lot more...