Like all media projects, the first thing that must be determined in the DVD process is the content, audience and goals of a project. The planning process is the time to explore the most dynamic and inventive ways to present your content in the DVD medium.

We must decide if the project is best suited to a DVD-V, DVD-ROM or Hybrid DVD. DVD-V discs adhere to the DVD spec and are designed to play in set-top DVD players with remote control interaction. DVD-ROM discs are designed to playback on a computer and leverage the increased storage capacity of DVD allowing full screen MPEG-2 video. Hybrid DVDs are designed to work in set-top DVD players, but then provide enhanced options when used in a computer for things like web connectivity.

An asset inventory is taken to catalog the number of MPEG clips and their running time. The number of menus, chapter or index points is determined. Are still images or text graphic screens to be included? Will the DVD use advanced features such as motion menus, multiple audio tracks, subtitles, or multiple camera angles? The answer to these questions is needed to calculate a bit budget which determines the amount of material that fits on a DVD disc. A flowchart must be created to guide the DVD creation process. This document includes all content structure, menu branching and interactive navigation of the DVD.

Encoding is the process of digitizing and compressing video and
audio assets. MPEG-2 is the compression scheme used for DVD. The DVD disc format, video duration and content style (i.e. talking head interview, high action, etc.) will determine the encoding bit rate and the amount of video that can fit on your DVD (see chart). Source video must be master quality in Betacam SP or Digital Betacam formats or will require transfer prior to encoding.

We recommend Constant Bit Rate (CBR) encoding for DVDs with one hour
or less of video and Variable Bit Rate (VBR) for more than one hour. VBR Encoding is more involved requiring two passes, an analysis pass and an encoding pass, segments that need more bandwidth can be re-encoded on a scene by scene basis. Inverse telecine is an option to remove duplicate frames added during film transfer and improve performance. Widescreen 16x9 video can also be encoded and DVD players will display it in native 16x9, 4x3 letterbox, or 4x3 pan & scan.

Disc Format	Sides	Layers	Capacity	Approximate Video Capacity
				CBR (8Mbps)	VBR (Avg. 5 Mbps)
DVD 5	Single	Single	4.7 GB	60 min	133 min
DVD 9	Single	Dual	8.5 GB	106 min	212 min
DVD 10	Double	Single	9.4 GB	120 min	266 min
DVD 18	Double	Dual	17.0 GB	212 min	424 min

Dolby Digital (AC3) is the audio compression scheme used for most DVDs. Stereo or mono tracks can be encoded simultaneously with the video. Alternate audio tracks or 5.1 Surround Sound require separate passes.

Authoring is essentially the process of transforming the flowchart and encoded assets into a functioning DVD. Navigational relationships are programmed to link video managers, title sets, program chains (PGC) and chapter points. A DVD-V can have up to 99 title sets each containing multiple chapters.

Menus can access both titles and chapters. Functionality needs to be embedded into the menus and sub-picture elements. Sub-titles and other sub-picture elements are indexed to timecode points within the MPEG clips.

Additional tracks and content are integrated, and advanced interactivity is implemented. Discs can be programmed to auto-start, programs can be routed to menus automatically, menus can be timed and clips can loop

Pre-mastering involves several steps: Formatting, Imaging, and Proofing. Formatting multi plexes (joins) the video and audio tracks into a single track, then organizes the files into the proper UDF (Universal Disc Format) configuration. Imaging copies these files to DVD-R, DLT (Digital Linear Tape), or hard disk for proofing and later replication. Proofing (also called Simulation) is the quality assurance step of the DVD process. Carefully viewing the content and checking navigation will insure that a DVD is ready for release. A DVD-R “one off“ disc is usually burned to test the program in different players to assure
universal acceptance.

Mastering is the actual physical fabrication of the DVD. A DLT containing the DVD data files is sent to a replication facility. In a process similar to laser discs and CD-ROMs, a glass master is created and used to press replicated copies. DVD-9 and DVD-18 discs require a bonding step to combine the multiple layers. The replication process usually requires one to two weeks depending upon the quantity and lead-time.