Issue: Volume: 27 Issue: 5 (May 2004)

The HDV Revolution


After all, JVC's original positioning for this new HD-on-DV format envisioned a high-definition future with consumers shooting vacations and birthday parties in HD and playing them back on JVC's plasma television monitors. At the time, however, few consumers had those HD-capable TV sets, and professionals were understandably leery of single-CCD camcorders serving any serious purpose. (Both the GR-HD1 and the JY-HD10 have just a single CCD, rather than the three CCDs—one for each primary color—of more professional camcorders). Minimal-ly, it's counterintuitive to expect a camera equipped with limited color and light sensitivity to try to stand up under the detail-revealing scrutiny of high-definition pictures.

However, the future has changed quite a bit over the past year. HDTV has gone from 15 years of hype to a regular production format for several prime-time and late-night television programs, as well as many sports broadcasts. HD motion-picture production, led by George Lucas and Star Wars Episodes I and II, is also gaining momentum. More important, for increased mass awareness, prices on HD-capable displays, including flat-panel plasmas and LCD TVs, are dropping, and an increasing number of cable and satellite TV providers are offering HDTV channels.
JVC's under-$4000 JY-HD10 camcorder set the bar for affordable High Definition Video (HDV). Now other vendors are readying similar models and supporting a new HDV format that builds on JVC's technology.




With that expanding awareness of HD comes the burgeoning aspirations of videomakers at all levels to shoot in HD, making JVC's basic idea of affordable HD production intriguing for videographers of more modest means. Even with its early single-CCD implementations, JVC clearly struck a chord with the independent video community. That's not to say that JVC has had a runaway success, although the "pro" JY-HD10 has had its share of vocal early adopters. Rather, the notion of affordable HD production has piqued curiosity.

JVC's competition recognized it, too, and that spawned a remarkable industry consortium. This collaboration of competitive camcorder makers (Sony, Sharp, and Canon) has now expanded and refined JVC's idea and coined the HDV moniker. Thus far, more than a dozen and a half editing-system, image-processing, and chip manufacturers have formally expressed support for the newly formed HDV standard, with several already including support for HDV in current products.

Admittedly, current claims of HDV support tend to put the proverbial cart before the horse. While an HDV standard has emerged in a basic form, that new standard goes beyond JVC's early camcorder implementations and, while HDV will undoubtedly beget more camcorder models for a variety of manufacturers, as yet none exist. Still, the simple fact that several companies are jumping in early is proof positive that interest in this new, affordable way to produce HD content is strong.

As of this writing, prior to NAB 2004, no new domestic HDV camcorders have yet been announced, although in March Sony Europe showed an unnamed three-CCD PAL HDV camcorder (roughly in the form factor of Sony's VX2100) that is expected to sell for less than $5000 later this year. JVC and Sony have both let be known their respective intentions to demonstrate at least one HDV model at NAB. Sony's is expected to be an NTSC version of the European product, and JVC's, rumor suggests, is a larger, shoulder-mounted camcorder in the style of JVC's GY-DV5000, with 3 2/3-inch CMOS CCDs and the ability to record to MiniDV or larger "standard" DV cassettes with up to 270 minutes of recording time. But, that won't be available until late in the year.

Like DV, HDV writes digital data to a tape cassette in a camcorder. The difference is that whereas DV is an intraframe, Motion-JPEG-like compression format, HDV compresses to MPEG-2, the format for DVDs and DTV. And since MPEG-2 compresses pictures both within the frame and temporally over a series of frames, or Group of Pictures (GOP), it can achieve much smaller file sizes for the same picture quality—or, in the case of HD, much higher resolution at the same file sizes as standard-definition DV.

JVC's existing JY-HD10 can record in both traditional 25Mbps interlaced 720 x 480 DV as well as HDV's 19Mbps 30-frame progressive mode at 1280 x 720. It also uses MPEG-2 to record at 720 x 480, but in 60-frame progressive. (Several DV camcorders today can internally process 60-frame progressive, but because of the limited bandwidth of 25Mbps DV tape, they effectively throw away half the information and record either 60-field interlaced DV or 30-frame progressive DV at 720 x 480.) Both the 720/30p and 480/60p modes of the JY-HD10 compress audio as MPEG-1, Layer 2, 16-bit, 48kHz stereo streams, encoded at 384Kbps. JVC also includes familiar FireWire transport for moving footage onto a computer.
Panasonic is staking out the high end of the HDV market with its AJ-HDC27 camcorder based on the DVCPro-HD format.




However, the consortium's HDV standard goes further to include 1080i HD, or interlaced 1440 x 1080, using the DVCassette's full 25Mbps. Curiously, the HDV standard defines the 19Mbps, 720p mode as an MPEG-2 transport stream, the same used by JVC in its exiting products, but uses "packetized" elementary streams for the 1080i mode. HDV uses a typical MPEG-2 4:2:0 chroma subsampling rate.

The glaring omission of the HDV consortium is the lack of any provision for 24-frame progressive. Since that is such a common frame rate for HD video production, one has to figure that marketing agendas got in the way of technological advancement. And, that's too bad, and also probably unnecessary.

Today, Sony and Panasonic are both enjoying the increasing success from their respective HDCam and DVCPro-HD formats. And, 24p is one of the major attractions of products like Panasonic's AJ-HDC27 VariCam ($63,000) and Sony's HDW-F950 CineAlta ($115,000) because of its flexibility in converting to 24fps film, 25fps PAL video, or 29.97 (30fps) NTSC video. The fear, presumably, is that the dramatically lower prices of future HDV camcorders will eat away at those gains in the professional marketplace, just as DV did to traditional analog formats. After all, JVC's JY-HD10 is just $3995 and Sony's yet-to-be-official three-CCD camcorder will be, by reports, under $5000. It's easy to see HDV camcorder sales cutting into the higher margin "professional" products. Or is it?

Panasonic, conspicuously absent from the HDV consortium, argues that the limited bandwidth of HDV is not sufficient for the quality necessary for true High Definition. Indeed, stories abound of how going to HD has forced newsrooms to completely revamp their sets because details that were once hidden by the imperfections of standard definition NTSC video became obvious and exposed by the higher resolution.

And certainly there is a difference. Panasonic's DVCPro-HD samples at 4:2:2 instead of 4:2:0 and runs at 100Mbps, four times the rate of HDV's 1080i and more than five times that of HDV's 720p mode. That's some serious compression for unforgiving HD content. Sony's HDCam SR format, used by Lucasfilm and others, can go as high as 440Mbps and has a mode for 4:4:4 RGB sampling. What's more, the simple quality of image components and lenses in such inexpensive camcorders can't come close to matching the quality of the professional gear "necessary" for true HD video.

Still, it's easy to draw similarities to MiniDV in late 1995. Professionals then viewed DV as a "low-end" format: a nice solution for the event videographer but not the serious producer. But DV, along with editing products like Apple's Final Cut, Adobe's Premiere Pro, Avid's Xpress DV, and others from Ulead, Pinnacle, and Canopus, changed the shape of video and postproduction. DV brought waves of new videomakers into the business and freed others from the bonds of expensive postproduction suites.

Time has settled many of those early DV debates about "good enough" quality, enabling and empowering many, but also reaching limits beyond which now lie appropriately more expensive solutions. With history as a guide, it's not hard to envision a similar place for HDV as an affordable high-definition format that opens doors and offers opportunities to those with talent and vision.

Jeff Sauer is a freelance writer, video producer, and director of the Digital Video Group, an independent testing and research organization for digital media.



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