Beyond HDV: The New MPEG-2 Cameras, Part 1

On the day installment one of the January issue of HDV@Work was published – which you may remember mentioned that Full HD camcorders were coming in 2007 – JVC issued a press release announcing the world''s first Full HD camcorder, the Everio GZ-HD7.

The JVC GZ-HD7 (MSRP of $1,799.95) is a small, lightweight camcorder that features a three-CCD imaging system. Each 16:9 CCD has 570,000 elements, delivering a 976x548 array of pixels each time the chips are read out. To improve sensitivity, the 1/5in. chips use a low-density design that enables the elements to be relatively large at 3.28 microns by 3.28 microns. In order to obtain 1920x1080 samples for recording, the red and blue CCDs are offset by one-half pixel from the green CCD in both horizontal and vertical axes.

The GZ-HD7''s analog front end (AFD) uses 14-bit signal processing. JVC has also developed a new HD-specific circuit that processes high-density interpolation signals for brightness and color. The circuit separates low-frequency and high-frequency components of the luminance signal to create an image with less moiré.

According to JVC, “4X interpolation processing” yields 1920x1080 output from 960x540 CCD elements. I''ve discussed interpolation several times in HDV@Work to make sure that everyone understands what interpolation can and cannot accomplish. The point to remember is that while interpolation will increase the number of samples, unless it is very sophisticated it cannot significantly increase the amount of information (resolution).

The GZ-HD7''s CCDs are read out progressively at 60Hz. Odd and even 540-line fields are recorded from alternate 1080p60 interpolated captures. (This process is amazingly similar to that used by Sony''s V1 and FX7.) This might set the table for a “pro” version of the Everio that scales each interpolated 1920x1080 frame to 1280x720. The 60Hz capture rate would yield 720p60 video. Moreover, were the camera able to be clocked at 48Hz – not that different from 50Hz for Region 50 camcorders – 720p24 recording would be possible.

In order to achieve maximum HD resolution, a camera''s lens has to be of very high quality. Fujinon supplies the Everio''s 10X optical-zoom lens that maintains nearly the same brightness (F1.8-1.9) throughout its f=3.3mm to 33mm zoom range by virtue of its three aspherical lens elements, one made of indexed glass. In addition, the lens surface is coated with a new Electronic Beam Coating (EBC) that greatly reduces degradation caused by light reflecting off the lens surfaces, leading to greater light transmission and reduced flaring and ghosting. In addition, to ensure precise prism/CCD registration, JVC has incorporated Fujinon CCD-mounting technology as used in professional camcorders. In addition, the HD Everio features optical image stabilization.

While the HD Everio provides fully automated operation for consumers, it also offers a wide range of manual controls for “prosumers.” These include a manual focus ring, manual white balance, exposure control, a zebra function, shutter priority mode, aperture priority mode, and a sharpness adjustment. A Focus Assist function displays the edge of the in-focus elements in color while the rest of the image is black-and-white, making it easy to confirm focus. Also included is a mic input for connecting an external microphone.

Is the GZ-HD7 an HDV camcorder? Technically it is not because there is no DV tape transport. Instead, a 60GB hard disk is used to record MPEG-2 Transport Stream. The camcorder offers three MPEG-2 recording modes: the Full HD mode records five hours of 1920x1080i VBR MPEG-2 video; the “HDV equivalent” mode records five hours of 1440x1080 CBR at 27Mbps (equivalent to D-VHS); and the SP mode records seven hours of VBR 1440x1080i. In all modes, stereo audio is encoded as MPEG-1 Layer 2 (MP2).

Because the GZ-HD7 records using an MPEG-2 Transport Stream, HD Everio recordings can be archived on Blu-ray discs using the bundled PowerDirector editing software with bundled PowerProducer that authors Blu-ray discs. PowerDirect is not a true NLE, so you''ll still need an NLE updated to support these formats. And, of course, you will need a Blu-ray burner.

The HD Everio is equipped with three digital interfaces: USB, HDMI, and IEEE 1394. USB is primarily for file saving, HDMI for digital viewing on large-screen displays, and the IEEE 1394 port streams high-definition video in FHD/SP/1440CBR modes. HD recorded material can also be output via analog component jacks - as well as downconverted for output as DV over IEEE 1394 or output in SD via the analog component/S-Video/composite output jacks.

In the second part of this camcorder preview, coming in two weeks, I will discuss some of the editing issues associated with the JVC HD Everio, focusing specifically on high-def DVD archiving and playback, and will look briefly at Sony's AVCHD-based offerings.

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Steve Mullen owns Digital Video Consulting that offers e-books on HD production. Currently, DVC (www.mindspring.com/~d-v-c) offers two eBooks: the Sony HDV Handbook and the JVC ProHD Handbook. In February, DVC will offer a new title: the Sony HVR-V1 and HDR-FX7 Handbook. Then in March, DVC will offer A Guide to Low Cost HD DVD Production.