In the world of digital camcorders, HD and DV have traditionally been at opposite ends of the spectrum. But JVC—recently joined by Canon, Sharp, and Sony—is working to change that with the HDV format, which blends elements of HD and DV to bring high-definition resolution within reach of videographers and prosumers. The four companies jointly proposed the HDV format in July and announced an agreement at the end of September. But even before the others formally signed on, JVC had begun rollout of two HDV camcorder models.
It's still too soon to assess the long-term impact of the new format on production in areas such as institutional video—corporate, educational, government, etc.—and event videography. But as early adopters begin to get some field experience with JVC's offerings, their first impressions provide some initial indication of the format's strengths and weaknesses.
What is HDV?
The basic appeal of HDV is that it allows an hour of HD video—compliant with the ATSC broadcast DTV standard—to be recorded with a moderately priced handheld camcorder on standard MiniDV videocassettes. JVC has introduced two models, the GR-HD1 for high-end consumers ($3499 list) and the JYHD-10U for professionals ($3995 list). The GR-HD1 has been offered on the Web (by an authorized dealer) for as little as $2000, a tiny fraction of any previous HD option. Not surprisingly, there's a great deal of curiosity about whether the format delivers the real deal or is HD in name only.
While widely reported, the general outlines of the JVC units bear repeating here (for full JYHD-10U specifications, see www.jvc.com/promotions/grhd1/professional/spec.html). Image capture on the camcorders begins with a lens that JVC describes as having "light gathering ability that varies between just f1.8 and f1.9" across the 10X range of the optical zoom. The heart of the system is a single 1/3" 1.18-million-pixel (1.14 million effective) progressive scan CCD. Also included on both models are optical image stabilization (lens shift system) and a rotating grip section (up to 90 degrees). The enhanced feature set of the JYHD-10U includes a 3.5" high-resolution 2 Megapixel LCD monitor, a color viewfinder, dual XLR audio inputs that support unbalanced input, an audio input level indicator on the LCD monitor, and a built-in Color Bar Generator.
The camcorders offer three recording modes. HD mode ("720/30p") is 1280x720 (16:9) resolution at 30 frames per second (progressive) using MPEG-2 compression with a six-frame group of pictures (GOP). SD Mode ("480/60p") also uses MPEG-2, capturing 720x480 (16:9) at 60fps (progressive). Audio in both modes is MPEG-1, Layer 2 16-bit Stereo at 384Kbps. At 19.7Mbps, the multiplexed video/audio signal recorded in both HD and SD modes offers about twice the bandwidth of the DVD-Video format. In DV Mode, meanwhile, the camcorders record conventional NTSC (DV-25 compression) with 16-bit PCM for two-channel audio and 12-bit for four channels.
A number of options are available for transfer and playback of recorded footage, starting with basic analog S/composite output. Built-in upconversion/downconversion capabilites yield four analog component output options compatible with a variety of display devices: NTSC (480 at 29.97fps interlaced), 4:3 ATSC (480 at 59.94fps progressive), and 16:9 ATSC at both 720p/60fps and 1080i/30fps (from HD Mode recordings only). Digital I/O is via iLink (a.k.a. FireWire or IEEE 1394), allowing output of 480i in NTSC DV-25, plus either 480/60p or 720/30p in an ATSC-compatible MPEG-2 transport stream (MPEG-2-TS) that is also compatible with the MTRM standard JVC uses for D-VHS.
Bridging the Stream
It wouldn't make much sense to buy either of JVC's HDV camcorders primarily for DV, so the major questions about the format relate to ATSC capabilities: how "good" is the footage, and what can be done with it after it's shot? The latter question arises because HDV's MPEG-2 digital output takes the form of a transport stream rather than a program stream. Both stream types are multiplexed collections of packetized video and audio elementary streams. But transport streams use a second layer of packetizing for increased protection against data loss in less reliable transmission environments such as DTV broadcasting. Because working directly with transport streams hasn't previously been of great interest in post-production, HDV isn't immediately usable with most NLEs, which work with elementary video and audio streams.
JVC bridges this gap in part by bundling a free MPEG-2 HD editing software package, MPEG Edit Studio Pro LE. The company describes the software as "the first con- sumer MPEG-2-TS software to provide frame accurate editing capabilities for digital hi-def images." The Windows XP-only package also facilitates conversion to program streams for burning of 16:9 progressive video to DVD with the bundled ImageMixer DVD program, as well as the output of HD content to D-VHS. Given that JVC's model 3000 D-VHS recorder is available for about $400, D-VHS is an attractive option for archiving HDV as well as for playback of edited HDV at full captured resolution.
JVC recognizes the limitations of its bundled "basic video-editing package," and recommends that professional customers utilize "more fully featured" applications. As of this writing, the list of alternatives that can work with MPEG-2 transport streams (as opposed to program streams) is fairly short, though it should grow as HDV catches on. One option in Windows is to capture to PC with JVC's included HD Capture Utility, then edit in Vegas Video 4.0 or Vegas+DVD from Sony Pictures Digital. Another choice is CineForm's Aspect HD ($1200), now shipping for Adobe Premiere 6.5 and soon to ship for Premiere Pro. Cineform describes Aspect HD as a real-time video engine allowing Premiere users to edit four or more streams of HD with transitions, motion, and color adjustment on "a standard fast PC" without adding special hardware.