November 21, 2005
By Brian Brodeur
Brian Brodeur, New York DVD, and Tony Tyler, Play-It Productions, gave an informative seminar on DVD Authoring at the Manhattan Center this past October for MCA-I members and guests. We were so impressed by their knowledge, we asked them to share some of it with our readers.
1. Learn about All Features and Terminology:As the DVD format has matured, there are many fundamental terms and features that the video producer and developer should be aware of. Most important, a DVD producer should be familiar with the basic features that are available with the DVD Specification, which include:
- DVD capacities: DVD5 (single sided/single layer, 4.7 GB) DVD9 (single sided, double layer, 8.54 GB) DVD10 (double sided, single layer, two 4.7 gb discs) DVD14 (double sided, double layered, two 8.54 gb discs)
- Audio and Video formats Audio: PCM uncompressed (AIFF/WAV), Dolby AC-3 (mono, stereo, multichannel) Video: MPEG2 format
- Standard Available Features: Subtitles (up to 32 languages) Multi-Audio Streams (up to 8 separate streams) Multi-Angle Video Streams (up to 9 separate streams) 4:3 and 16:9 video available Menu button interactivity On-Demand rewind/fast forward On-Demand Chapter ‘next’ and ‘back’ NTSC or PAL video formats Region Coding (1-8) Copy Protection (CSS and Macrovision)
For more information, please visit the DVD FAQ list on www.dvddemystified.com
2. Produce with the Remote Control: The standard interface for many consumer electronics, including DVD players, is the remote control. The DVD remote control interface includes a small group of buttons that allow for all DVD players to provide a standard interactivity and access to the many standard features of DVD. First and foremost, menu navigation (via a highlighted indicator) is accomplished thru use of left, right, up, and down buttons – along with an ENTER button to make selections. Also, most remotes feature a ‘TOP Menu’ and ‘DVD Menu’ button that allows the user to jump out of video playback into the DVD menu structure. Some remotes offer only one ‘menu’ button, and many authoring programs provide ‘menu’ button customization. When developing a DVD project, the producer and development team should be conscious of the remote control functionality, and the user’s experience via the remote control’s interface. Successful DVD’s utilize a common sense approach to navigation that is intuitive for the user and his/her remote control.
3. Duplication vs. Replication: Replication refers to the manufacturing process of stamped aluminum discs – just like you would buy or rent at your local retailer. Duplication refers to the ‘burning’ process of copying DVDRs on a computer or duplication tower system. There are advantages to both of these processes. Replicated discs are generally more compatible in players, although there are often minimum numbers of units that a replicator will produce. Duplicated (burned) discs are less compatible in players than replicated discs, but it is easy to produce short-runs of DVDR’s. As newer players are produced, DVDR playback is becoming more compatible, and dual-layer 8.54 GB DVDR discs are available.
4. DVDR Media: There are many manufacturers, price ranges, and formats of DVDR discs. The most common format is a single sided, single density 4.7 GB DVDR disc. These discs vary between a few formats – the most common being DVD-R and DVD+RW. The DVD-R is essentially a ‘write-once’ burnable disc and The DVD+RW is a re-writable DVDR disc. Generally speaking, the DVD-R format disc is the most compatible burnable DVDR on the market – yielding 75%-80% playability in the ‘real world’ (as of this writing). The latest technology is the dual layer DVD-R burnable disc – mostly used to proof dual-layer projects that will be replicated as DVD9 discs.
5. Packaging: As much as the development of the interactive DVD is important, the printing and packaging is a very important aspect to any project. Many options are available, including simple DVD’s in a sleeve or extensive ‘DigiPak’ cardboard 4-color packaging with foil embossing. Other aspects of final packaging to consider are barcodes for retail products, spine stickers, shrinkwrapping, and type of DVD box. The popular plastic black box that is called an ‘Amaray’ style box.
6. Consider Your Authoring System: Just as you would not use a compact car to haul a 2-ton trailer, video producers should choose the appropriate authoring and encoding system to develop their projects. Manufacturers offer a wide range of software that ‘author’ and ‘encode’ DVD’s – from free bundled packages such as Sonic Solutions’ DVD-It, to Apple’s popular DVD Studio Pro, to Sonic Solutions’ premier system called Scenarist. Each tool has it’s own benefits and price range, but the bottom line is DVD software is becoming more and more easy to use and widespread on a consumer or pro-sumer level. Professional authoring facilities that are producing retail-ready product widely use hardware encoding and high-end authoring packages due to the efficiency and reliability of the final rendered image. The best advice is to contact your local software vendor and get a demonstration of different authoring packages. Also, talk to experienced DVD professionals and test any disc you author.
7. Consider Multi-Language: One of the most powerful features of DVD is its use of multi-audio and subtitle streams. These features allow for easy localization of content – and thus allowing ONE disc to serve multiple geographies and markets. Instead of having to ‘dub’ VHS copies into each language, DVD’s allow you to turn subtitling on or off in real-time by using the ‘subtitle’ button on your DVD remote. Also, by using the ‘Audio’ button on your remote, you can change from an English audio track, to a recorded language translation – and the video and audio stay perfectly in sync every time.
8. Dolby vs. PCM: DVD’s are able to playback ‘compressed’ Dolby AC3 formatted audio streams as well ‘uncompressed’ PCM formatted streams. PCM streams are usually AIFF or WAV files, and DVD’s only accept 48khz/16bit audio. ‘compression’ refers to data rate throughput – and not ‘dynamic’ audio compression. An essential concept regarding DVD is based on ‘megabit’ throughput – which means how much data is coming thru the pipe when you play your DVD. When using PCM uncompressed audio, the audio stream adds 1.5 megabits of data. Using Dolby Digital AC3 adds roughly 0.2 – 0.5 megabits of data. Dolby is obviously a more efficient (smaller) data stream to add into your disc output, and thus inherently will make your disc more playable due to the more compact data stream.
9. Bitrate Maximum: The total bitstream (including video, audio, and subtitles) cannot exceed 9.8 megabits per second of throughput – and I personally recommend not going anywhere beyond 8.5 megabits total. With throughput measured in megabits per second, here’s some math: Encode video at 5.5 mb/sec, audio is Dolby AC3 at 0.256 mb/sec, and you have two subtitle tracks at .02 mb/sec each. Your total ‘average’ throughput for your program would be 5.8 mb/sec (adding each of the asset rates together). Note that sometimes the video rate may spike up to accommodate detailed sections of video, but your encoder should outline that parameter for you. Some pro-sumer encoders don’t give you control of these encode parameters – rather giving options such as ‘good’ or ‘best quality’. It is worth testing several clips of video until you get comfortable with the quality and memory usage that each different rate provides. For further information about this very important topic refer to your authoring/encoding software manual regarding ‘bit budgets’ or consult your local DVD professional.
10. Proof Proof Proof! The best advice possible for any experienced or novice DVD producer is –TEST TEST TEST. Make sure you proof your project as much as possible on many different players. As DVD players have become very affordable (most under $100), I recommend purchasing several different makes and models and testing your project on each player. Also, computer DVD players can be helpful, although I do not recommend them for ‘critical’ viewing due to common software decoding irregularities and lack of interlaced monitoring. Rent as many discs as you can, review the latest ‘high-end’ productions. Keep in touch with your local industry representatives and authoring consultants, and most of all – have fun with you DVD projects!
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Brian Brodeur is the founder and director of DVD development at NewYorkDVD www.newyorkdvd.com. He can be reached at 212-346-9383 (34-NYDVD).