About 1 year ago...................
kipinet.com
Connecting the Codecs
DVand MPEG move into nonlinear editing
By Susan Maier
What started as a murmur at NAB in April grew to a buzz at the International Broadcasters Convention in Amsterdam this fall. Spurred by the arrival of DVD and, of course, the mandated transition to digital-television broadcasting in the United States, MPEG-2 is moving not only into video distribution and transmission but into the rest of the production chain. "By the year 2001," predicts the industry consultant Jon Peddie of Jon Peddie & Associates, "MPEG-2 and DV interfaces will dominate the consumer, prosumer and professional videographics markets."
Sony started the MPEG-2-in-production ball rolling at NAB '98 by announcing its intention to develop video cameras and VTRs based on the MPEG-2 standard, becoming the first major player to venture publicly into the arena of MPEG-2 acquisition. Smaller companies-notably FAST Multimedia and Vitec Multimedia-also came forward with demonstrations of fledgling MPEG-2 nonlinear-editing products.
The response at the show, however, was not overwhelming-to say the least. In fact, many observers seemed downright puzzled. Who needs an MPEG-2 camera or recording deck, especially when all-digital DVCAM and DVCPRO equipment is available? And what benefits does MPEG-2 offer to a nonlinear system that Motion-JPEG doesn't?
By IBC in September, the attitude had changed. FAST demonstrated a working version of its MPEG-2-based 601 system, and it generated some of the loudest buzz at the show. The spec sheets for 601, which is scheduled to start shipping this quarter, promise features comparable to those found in mid-range to high-end Motion-JPEG nonlinear-editing systems, including real-time editing with two video tracks and an uncompressed titling track; real-time cuts, dissolves and wipes; an unlimited number of video, overlay and titling tracks; live video inlay; drag-and-drop editing and flexible three-point editing; and editors for keyframeable DVEs, wipes, keying and color and filter effects.
"MPEG-2 is the only worldwide, professionally recognized digital compression format," says Tom Patrick McAuliffe, public-relations manager at FAST. "We really feel that Motion-JPEG is dead-unfortunately, to the detriment of some of our other products. Two years from now, any [nonlinear] manufacturer that doesn't have an MPEG product will be out of the race."
Peddie agrees, if not with the two-year timetable, at least with the forecast that MPEG-2 will soon become widespread in video production. "The prosumer and professional markets are rapidly migrating to standard formats," he wrote earlier this year in a white paper commissioned by C-Cube Microsystems. "In early 1998, there [were] just a few companies offering affordable nonlinear digital video editing MPEG-2 systems [or subsystems]. However, in the market segment of the older CD-ROM area, which uses MPEG-1, there are dozens of suppliers. All of those suppliers have indicated they plan to move to the MPEG-2 format."
Among the nonlinear-system vendors that Peddie cites as planning to move to MPEG-2 are Avid, FAST, Matrox, Pinnacle, Scitex Digital Video, Sony, Truevision and Ulead. Of them, FAST is the first to bring a product to market. Adobe, Media 100 and Panasonic are also reportedly looking closely at MPEG-2 for editing.
"At NAB, FAST was part of group of companies-which also included Hewlett-Packard, Media 100, Snell & Wilcox, Sony and Tektronix-that founded the Pro MPEG Forum," McAuliffe says. "The goal is to get a bunch of manufacturers together to insure that when these MPEG-2 solutions are brought to market, they are fully cross-compatible."
Not that consortia and similar groups are any guarantee of compatibility. As only one of many notable examples, a consortium was formed to promote unification among different manufacturers' adaptations of the IEEE 1394 standard, a group to which FAST also belonged. "As we're now seeing, some versions of IEEE 1394 are not compatible with others," McAuliffe admits. Apple has FireWire; Sony's has i.LINK; and JVC has Digital Link. "Rumor has it that Panasonic is going to come out with its own name, as well," he says.
Studio Test
So why MPEG-2?"Maintaining an MPEG-2 stream throughout the editing process eliminates the artifacting and signal concatenation issues that you often face when you transcode M-JPEG to MPEG-2," according to McAuliffe. "It is much easier to take an editable MPEG-2 stream than an M-JPEG stream and convert it to 4:2:2 MPEG-2 Main Level at Main Profile, the standard for digital television and DVD distribution."
FAST is positioning 601 as a successor to its Video Machine and going after corporate, government and independent producers, as well as mid- to small-market broadcasters. "The mid- to small-market broadcasters are starting to recognize that, like it or not, they're going to have to embrace MPEG-2 in the new DTV era," McAuliffe says. "So are the corporations. For example, we're now talking about 601 with American Airlines and Visa, ... which do their own weekly or video programs that are distributed worldwide by satellite."
Mike Billingsley, a principal of Videographic West in Vail, Colorado, is an independent producer who has been beta-testing FAST's system. 601 is the "first desktop nonlinear system to ding my bell," he says. Videographic West produces corporate video projects as well as the cable programs Ski TV and Golf Life. "We do a lot of national work, and I've looked at a lot of systems to edit on," Billingsley says. "I've looked at Quantel's Editbox, but spending $160,000 for a system is a big decision for a small company up here in the mountains of Colorado.
"I was one of those guys who learned how to make a PC work. Macs frustrate me, because I could never get into the core of the system and break it down. We're fairly isolated here in Vail and like the fact that we can control the PC platform. But up to now, there has been a big void in the market for people looking for a good editing system on NT in the $40,000-to-$50,000 range."
Billingsley is interested in 601 because he can use it to encode an MPEG-2 stream "right on the board," he says. "DVD is going to become reality quickly. With 601, we'll be able to output an [MPEG-2] stream and send it directly to an authoring house. Or we'll be able to take MPEG-2 streams on hard drives to an uplink site for satellite distribution. The sooner this becomes reality, the better.
"Wired digital networking is something we're also really looking into strongly right now," he concludes. "The first step is learning more about using MPEG-2."
In the Chip
One of the year's biggest developments in the area of MPEG-2 editing is the release of the DVxpress family of chips by C-Cube Microsystems. A DVxpress card, in fact, forms the basis of 601's MPEG-2 capabilities. With DVxpress, C-Cube has put a programmable video-compression engine on a single add-in board. The card, according to the company, contains a micro-SPARC RISC core and offers special hardware for video I/O, motion estimation and compensation, DCT, IDCTs, variable-length encoding and decoding, video scaling and compositing, and audio capture.
"The benefits of digital video are obvious and well known," says Joe Sutherland, product marketing manager at C-Cube. "But you need compression to make digital video work." One of the major drawbacks to MPEG-2, he notes, has been the high cost of the encoding and decoding hardware. C-Cube's single-chip architecture has brought this cost down; moreover, MPEG-2-compressed video provides a serious savings in bandwidth over M-JPEG. This, in turn, will allow nonlinear vendors to offer multiple-stream editing, real-time special effects and other features now found only on the big-ticket systems in nonlinear editors selling for $1,000 to $2,000, he says.
C-Cube offers the DVxpress 7110 for the high-level consumer market (this chip is expected to form the basis of those "$1,000 to $2,000" systems); the DVxpress 7112, a professional version for systems that will sell in the $10,000-and-higher range; and the newly released DVxpress-MX, which provides transcoding between the DV and MPEG-2 formats. "We see the market migrating to two formats-DV on the acquisition side and MPEG-2 on the distribution side,"Sutherland says. "These are the formats that are becoming dominant for their applications. What is driving us is the need to provide a seamless bridge for end-to-end digital production, allowing users to mix the formats together or make a transition between them."
DV Everywhere
MPEG-2 is still making its way into the nonlinear-editing arena. DV, on the other hand, has arrived. The past six months have brought an explosion in the number of available and promised DV-based nonlinear-editing systems, some of them featuring dual-stream editing and other sophisticated professional capabilities. DV nonlinear editors are available as turnkey systems-for example, Panasonic's DVedit, which contains Truevision's dual-stream DVCPRO-based TARGA video engine, and Sony's ES-3, which supports the IEEE 1394 (i.LINK) standard for transferring DV signals from cameras and decks-or as card-and-software combinations.
DV can still be somewhat dicey for editing, however, so some manufacturers are opting to transcode DV signals brought into the system to M-JPEG before editing processes are applied. Media 100's Finish system, due for release later this year, uses this approach. "DV is a 4:1:1-based signal," says Bob Barnshaw, product manager for Finish at Media 100. "It also uses fixed-block compression-that is, it compresses video in a rectangular grid-so when you begin to apply processes such as keying, special effects and titling, the DV media will start to break down because of its lack of chrominance and its compression scheme." M-JPEG, on the other hand, "is 4:2:2-based and uses an adaptive compression technique, bringing the image through one pixel at time. The result is a signal that is more resilient than if you had left it in DV form," he says. "That is why our system has been designed to be integrated with DV by changing the signal from DV to M-JPEG."
But, Barnshaw says, "we're very, very aware of the market trend right now. The market as a whole is really in the due-diligence stage when it comes to MPEG-2. What people have to remember is that it's not yet a broad standard. It's more an emerging standard, and we're playing close attention to the market's adaptation to it." |
