DVD Developments: So what is DVD?

Transcription

1 DVD Developments: So what is DVD? DVD was originally an acronym for Digital Video Disc, but more recently this has been 're-purposed' (a currently over-used description) as Digital Versatile Disc - to reflect the fact that the standard has been developed to include DVD-ROM discs and other formats which can contain other types of data such as computer files, software applications and databases. DVD-Video looks all set to be the replacement for VHS videotape - although time will tell whether this becomes a reality or not. Signs are very healthy in the USA, although the ball has yet to get rolling in Europe. Standard DVD-ROMs will offer around six times the storage capacity of a CD and the next generation of personal computers, which will be released in the latter half of 1998, will be fitted with DVD -ROM drives as standard to take advantage of this. Most observers agree that DVD-ROM will almost certainly succeed as a format for computer data storage and for delivery of interactive titles. So, DVD-ROM will replace CD-ROM in the computer industry - and this is likely to help to make DVD-Video a success along with it. Currently, discs cost around 2 each to produce and turnaround is between 7 and 10 days here in the UK, although prices can be expected to fall quickly if the format takes off. The various types of DVD format include DVD-Video, DVD-ROM, and hybrid titles. You can put whatever you want on DVD-ROM and access this using a DVD- ROM-equipped PC. DVD-Video will play back on both DVD-equipped PCs as well as on consumer DVD-Video players, and DVD-equipped PCs are now shipping which include a DVD-ROM player, an MPEG 2 video decoder and a Dolby AC3 audio decoder. There are also DVD-RAM, DVD-Audio and DVD-RW (rewritable) formats. How do you create a DVD disc? To create a DVD-ROM disc you can simply use a data formatter with whatever data you like to create a disc image and then supply this to a pressing plant to replicate. Typically you will print the disc image onto a DLT digital linear tape, although it is possible to supply the image on DVD-R or DVD-ROM disc. For a multimedia DVD-ROM featuring interactivity, there are no restrictions on which software you use, so you can use PowerPoint, Director, ToolBook or whatever you like. And if you want to use video and audio on such a title you can choose between Dolby or MPEG audio, QuickTime, AVI or MPEG video. For DVD-Video, the format is much more tightly-controlled because it has to work on specific players. The data preparation stage includes video encoding, audio encoding, menu preparation and sub-titling. For encoding you need an MPEG 2 video encoder and an audio encoder which can be Dolby Digital or MPEG2. Then there is authoring where you take all this data, load it into the software, and create the navigation. After authoring comes pre-mastering to create a disc image which

2 is used by the pressing plant to replicate from. You also need the DVD premastering medium which is either a DLT (Digital Linear Tape) - or a DVD-R if the volume of the disc is below 3.9 Gb. The data stored on a DLT uses the DDP 2 Disc Description Protocol which is a way of describing what is on the DLT in such a way that it can be delivered to a laser beam recorder at the pressing plant. Hybrid titles are DVD-Video compliant - so they will play on consumer players as well as on PC's with DVD capabilities, but they will provide more features when you play them on the PC. Why? Because the PC can provide enhanced interactivity and animation, Internet access and mouse control. Given the market situation, hybrids are the best titles to make because they give you the largest potential audience. Also, they take advantage of the PC's capabilities - so they are not limited in terms of their interactive features. Yet another advantage is that you can have single-inventory releases - DVD-Video discs that offer DVD-ROM features to PC-users. One disadvantage is that they are more difficult to create - because the authoring process is more complex. What is DVD-RAM? There are various specifications for DVD-RAM devices which will be used as large storage devices for computer data. DVD-RAM and DVD-RW are both outside the main DVD spec. Both of these are rewritable formats, but specified by different groups of manufacturers. You can buy these drives now, but there are still issues that need to be resolved. Bob Augur of Electric Switch explains: "The main issue here is whether DVD-RW is a proper DVD disc or not. Philips, Sony and Hewlett- Packard have one view while Matsushita, JVC, Pioneer, Toshiba and others take a different view. The Philips group say that the DVD-RW format should use a particular way of writing to disc using Philips and Sony patents while the other group specifies writing using their patents. However, DVD-RW drives will also read DVD-ROM, DVD-Video and DVD-R discs. Because the drive will read all of these Philips and Sony say that discs written with these drives are part of the DVD family. However, a disc produced in such a drive is not a DVD-RW according to Matsushita - who call this a DVD PC-R/W disc and say that it is purely incidental that DVD players can read DVD-ROM discs. DVD-RAM is the proposal from everybody except Sony in the Japanese DVD Forum for a RAM format. They say this is part of the DVD family." Matsushita/Pioneer recently announced their DVD- R/W format which can store 3.95 Gb per side and has the same record and playback characteristics as DVD-R. Unlike DVD-RAM discs these can officially be used in a DVD-Video player or DVD-ROM drive. This format may appear to be a better choice for computer data storage as it will hold more data than a DVD-RAM disc which can only hold 2.6 Gb. However, DVD-R/W is designed for writing all the data in one pass, so it isn't really suitable as a general computer storage device - it is better for storing large audio or video files. There will also be a DVD-Audio only specification, although this has not been fully agreed as yet. This will be able to use the new surround-sound formats along with higher-quality audio at sampling rates up to 96 khz with 24-bit resolution. To complicate matters even further, Sony and Philips are working on another special format using a 100kHz sampling rate called Super Audio CD which will hold about one and a half times as much as a normal CD. This will use Sony's new Direct

3 Stream Digital (DSD) technology and is scheduled for early These discs will use a special player but should also be able to play on DVD players - although some may not. What they will do for sure is playback on standard CD-Audio players - because they are manufactured with a standard Red Book CD layer along with a high-density layer which uses DSD audio. The DSD audio layer will have three tracks: an inner track providing stereo audio, a second track containing a 6- channel surround mix and an outer track containing other information such as liner notes and images. Daikin envisage that you will be able to master DVD- Audio-only discs using their Scenarist authoring software and they will be getting involved with Sadie and Digidesign for this. Of course, it is possible already to effectively make a DVD-Audio disc by putting one single frame of video onto a DVD-Video disc and then just using the audio part. Implementation Issues: In the USA, DVD-Video has really started to take off and the discs and players are selling well. One issue is localization for European releases. The essential issues here are that NTSC video may need to be converted to PAL and re-digitized; dialogue may need to be translated and re-recorded in other languages; and subtitles and any other on-screen text may need to be translated and re-worked onscreen. In the UK, any video needs to be cleared by the British Board of Film Classification. This even applies to video and sub-titles which may be on the same disc but in other languages for use in other territories (in case people in the UK look at these!). There are similar classification authorities in other European countries, such as FSK in Germany and FSS in Italy, but the difference is that in the UK this is regulated by the law of the land while in other European countries it is a voluntary code. However, this can be a complex business - as Bob Augur has learnt from his early experiences. "What I have discovered over the last 12 months is that technology is not the issue! It is people and how well they organise things - or otherwise! The most likely problems occur with sub-titles. The next most likely situation is that people can't get the translations done accurately and in time for things like menu screens, biogs, etc. For example, when you have six different languages on one disc and you need to sort out better translations than those originally provided you could be stalled for maybe a week - with your 12 Gb of hard drives all full up." Another issue is copy-protection for video content. There are two video copy protection schemes commonly employed - CSS (Content Scrambling System) and MacroVision - both mainly intended for the DVD-video industry but of interest to other developers. CSS is a way to encrypt the video and DVD players all have descrambling chips for this form of encryption. One part of the encryption key is applied at the authoring stage and one at the manufacturing stage. If you just copy the video from a disc you won't have the replication plant's key - and you need both keys to successfully replay the video. This is called Digital Copy Protection (DCP). There is also ACP - Analogue Copy Protection - and every DVD player uses this as well as DCP. MacroVision lets you play back analogue video to a TV, no problem, but if you try to record this to VHS - it won't. The TV can handle the MacroVision modulated video, but the VCR cannot. MacroVision is already used on Disney and some other VHS releases. It is worth keeping in mind that these systems will just stop 'mom and pop' from copying video - no serious

4 professional video pirate will be stopped. Neither of these systems are mandatory, so you can choose not to use them - but if you do you will incur extra production costs. So there are licensing and implementation issues to consider here along with issues such as localization, authentication and timed releases. Digital watermarking systems are also on the way for audio and other time-based multimedia elements. These will add specially coded and unobtrusive information which will run throughout the time-based material. This can subsequently be monitored electronically to establish how much was used and to identify who owns the rights. Authoring Systems: Various high-end authoring systems are available, or about to become available, from Philips, Panasonic, Minerva, Digital Vision and Optibase. One of the first systems commercially available came from Mac-based Sonic Solutions although this used Daikin's Scenarist II DVD authoring software running on a Silicon Graphics machine. Daiken and Sonic Solutions have recently severed their relationship and, significantly, Sonic's share prices as quoted on NASDAQ have fallen drastically of late. Sonic originally sold quite a number of units at between $150k- $250k using the Daikin authoring software - but have now released a lower-cost system, priced just under $100,000, using their own authoring software. Daiken have announced an NT version of their Scenarist II authoring software at under $30k along with various strategic alliances with other audio companies including SADIE and Digidesign. The high-end authoring systems currently use two or more computer platforms, such as Mac and SGI, but things are moving in the direction of Windows NT - especially as more MPEG encoders/decoders are available for this. For instance, the Optibase DVD Fab! system will use the NT version of Scenarist II when this becomes available around April 1998 to provide a one-platform authoring solution priced at $100,000. DVD caught on originally at the higher-end video and film facilities, but this year many expect to see both the corporate and multimedia sectors buying authoring systems. German company, ASTARTE, the well-known developers of Toast CD- ROM and CD-DA mastering software, are now working on DVD-Video authoring software for the Macintosh which is likely to be launched at CeBIT Sonic have also just announced an easy-to-use product for the corporate market which produces a DVD disc image from Powerpoint presentations on the Mac. This is called "DVDit!" and will retail for just $899. A forthcoming version will also let you work with Premiere and HyperCard projects. DVDit! was well-received at the recent Macworld Show in San Francisco and is expected to be available from March '98. With all this activity going on among the tool developers, things are looking good for the coming year. Assuming that DVD-Video continues to rise in popularity in the USA and makes at least an encouraging start over in Europe and elsewhere, then a number of high-end authoring systems will be needed to produce the stream of major software titles which will be released. As the corporate sector's useage starts to get in gear, especially with the lower-cost systems now becoming available, prices can be expected to fall steadily until affordable tools become available for all. I can easily envisage a time when individual PC-users will want to be able to create DVD-R discs, migrating upwards from CD-R, so that they can

5 take advantage of the higher capacities available. Video professionals may be more concerned about the way DVD-Video is shaping up. Abbey Road Interactive's Sarah Bradley was optimistic about the way the DVD-Video market is developing, quoting last year's encouraging figures for sales in the USA while referring to the fact that things are developing more slowly in Europe. "There are no reliable figures on installed base for Europe as yet, but the figures for the USA as published in the Phillips DVD Report newsletter sourced from the Consumer Electronics Manufacturers Association up till November 21st 1997 show that sold last year there were 15 million VCR decks, 2 million TV/VCR combinations, 300,000 DVD-Video players and only 44,000 Laserdisc players - a figure which has fallen by nearly 70% compared with the 1996 sales. I expect that when the figures for Christmas sales of DVD-Video in the USA appear, they will show a market more than large enough to justify the release of DVD-Video titles. People will now make money if they release a DVD-Video title which sells adequately to this installed base." DVD Authoring Studios Abbey Road Interactive: EMI have set up a DVD authoring and mastering facility at Abbey Road studios where they have produced the first DVD title released in the UK - "Queen's Greatest Flix". I spoke to Sarah Bradley - Digital Video Manager at Abbey Road Interactive - who told me "Currently the main tool we are using for DVD-Video authoring is Daikin Scenarist which we are running on a Silicon Graphics 02, but we are also a beta test site for Sonic s Producer. We are very happy with Scenarist, but we are also interested in the way that Sonic have approached the design of Producer - having learnt from the first generation of tools." I noticed that there were several different computer platforms in use, and asked what the different machines were used for. "To digitize video assets here, we are using a unique solution from IBM. We have a beta test agreement with IBM s research centre in Yorktown Heights in the USA and they have provided us with a complete MPEG 2 video compression system running on a Windows NT machine tailored to our needs. We have found that the quality of this system is the best we have seen so far. We use a Sonic Solutions SonicStudio system to digitize the audio on a Mac and we create graphic elements using Photoshop and if we need to animate any video we would do this using After Effects - running both of these on the Macintosh platform. So we use the Windows NT machine to digitize the video assets, a Mac for the audio and graphics, a Silicon Graphics machine for the authoring and another Mac for emulation - using either the Sonic Solutions PrePlay or the Daikin Emulator." Electric Switch: MD Bob Augur explained"in 1993 we decided to set up Electric Switch to do Video- CD and CD-i - but these never really took off in a big way in Europe, despite the fact that Video-CD has been a great success in China. Early in 1996 after seeing the Philips DVD demos at Milia we were convinced that DVD was the way to go. In October 96 I went along to look at several facilities in the USA which had already

6 started DVD production - most notably DVCC, the Digital Video Compression Corporation, which is based on the lot at Universal. DVCC were using the Panasonic system which I was very impressed with, so I decided that Panasonic was the system to go with. We eventually obtained a system via Panasonic OWL (Office Workstations Ltd) in Edinburgh - a wholly-owned subsidiary of Matsushita, Panasonic's parent company - who had written the software for the system used at DVCC. The whole installation cost us around $1.5 million - for the encoder, the authoring system, the mastering software, the disc verification software, and for access to Matsushita's Core Technology R & D program. The Panasonic system does not include digital audio encoding facilities, so we chose a Sonic Solutions workstation for this, although we use a Philips encoder for MPEG 2 audio. The Panasonic encoder actually costs about $800,000 - but you have to reckon in all the peripherals you need, such as the master-quality VCRs, D1 machines or whatever to use at the front end. So the $1.5 million includes the D1, the noise reduction, the computers, the hard drives, the digital betacam, the video infrastructure, and so forth. Nevertheless, business is growing all the time and we anticipate that we may get a second system later this year. In the USA there are many big name studios who insist on using DVCC's Panasonic facility. Here in Europe, Polygram are using our facility for the same reason. In fact, we are working with most of the major European distributors who recognize the investment we have made both in equipment and in people who know what they are doing." Disctronics/Freehand: Disctronics, the UK's largest independent CD manufacturer and Freehand, the computer graphics and multimedia company, have recently joined forces to provide a one-stop shop for DVD production and have just produced their first demonstration DVD to present at Milia '98 in Cannes. Chris Wright, MD, told me "With our new tie-up with Disctronics, one of the UK's major CD-replication companies, we can offer a complete one-stop service for DVD production." And which DVD Authoring system have they chosen? "We have bought the Sonic Solutions DVD system, although we intend to test the Optibase DVD Fab! system as well. Our sales company has always been a reseller for Optibase MPEG encoding systems. However, the Sonic Solutions Mac-only system was the only one available when we decided to get started with DVD production. The Sonic system is very good, despite a few teething troubles at first. Also, some people have been holding back until the issue with Dolby AC3 vs MPEG-1 Layer II audio was resolved, which it now has been. Nobody wants multiple standards!" Wright then addressed the subject of how DVD is developing in Europe. "In Europe, people are still waiting. There may be a delay on players coming to market until they will support both Dolby AC3 and MPEG2 audio. The people who own content now need a push to release titles. There is likely to be a large corporate market for both DVD-ROM and DVD-Video. Companies who have produced corporate video and distributed these on VHS in the past are looking for the higher quality of the DVD-Video discs for the future."

7 Mike Collins 1998