The following table shows the first 374 bytes of the file VIDEO_TS.IFO provided with the sample DVD project. These data bytes form the required data structure named VMGM_MAT that stands for the Video Manager Information Management Table.

This table provides essential information regarding the disc and pointers to other major data structures on the disc. The DVD player must perform some basic data verification to check for the validity of this required data structure. When a sector address is used, it is implied that a standard DVD sector takes 2048 bytes of storage.

Video Manager Information Management (VMGM_MAT)
Offset	Bytes	Description	Value
0	12	Video Manager Identifier	DVD VIDEO_ VMG
12	4	Last sector of VMG	5
16	12	Padding bytes
28	4	Last sector of VMGI	2
32	2	DVD Specifications version	1.1
34	4	VMG Category and Mask for Regional Codes	0
38	2	Number of volumes of this DVD	1
40	2	Current volume	1
42	1	Disc side	1
43	19	Padding bytes
62	2	Number of video title sets	1
64	32	Provider ID
96	8	VMG Pos Code
104	24	Padding bytes
128	4	End byte address of VMGI_MAT	1275
132	4	First-Play PGC Start Byte	1024
136	56	Padding bytes
192	4	Start sector of VMGM_VOBS	0
196	4	Start sector of VMG_PTT_SRPT	1
200	4	Start sector of VMGM_PGCI_UT	0
204	4	Start sector of VMG_PTL_MAIT	0
208	4	Start sector of VMG_VTS_ATRT	2
212	4	Start sector of VMG_TXTDT_MG	0
216	4	Start sector of VMGM_C_ADT	0
220	4	Start sector of VMGM_VOBU_ADMAP	0
224	32	Padding bytes

More details of these structures from a provided DVD project are explained in the The Unofficial DVD specifications Acrobat PDF ebook. The use of each of the fields defined in the above data structure will be explained in details in the following pages.

In general, once the DVD player is able to read the contents of the VMGM_MAT structure of the title provided with this guide, it has a general idea regarding the audio and video contents of the disc (how many video title sets, whether the title menu is present or not, how many audio and video streams are available, etc.). Most importantly, the player knows what to do first by locating and reading the contents of the data structure First-Play Program Chain (PGC).

The Unofficial DVD specifications is now available in Adobe Acrobat PDF ebook format. If you do not have a permanent Internet connection, this ebook can save you a lot of connection time by reading it off-line and it contains more information than presented on the web pages. Each DVD instruction is organized as a bookmark so you can get to the desired page of any of the 36 DVD commands with just a click.

All the research have been done for you and summarized in an easy-to-read format. This is the only ebook of its kind so save yourself a lot of time and efforts searching. You cannot get similar high-quality information anywhere else at this price.

The Acrobat PDF version offers these immediate benefits:
Having more detailed information than on the web pages.
Understanding DVD terminology and architecture.
Better use of authoring products such as Sonic Scenarist, Adobe Encore, DVD-Lab, IFOEdit, etc.
Detailed knowledge of DVD virtual commands.
Ability to verify and edit data structure fields using IFOEdit with a sample DVD title.
Understand how DVD menus work with navigation commands.
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...