Computer Video

HomeSoftwareArchiveTop TipsGlossaryOther Stuff




The uneasy marriage between camcorders and PCs is finally consummated with the arrival of the JVC GR-DVM1, the first camcorder with PC connectivity as standard



You can tell straight away that the GR-DVM1 is different, itís the first camcorder weíve encountered, with a CD ROM in the accessory pack... The obvious question is why? Simple, in addition to all the usual movie-making functions the DVM1 comes with all the necessary hardware and software, needed to export high-quality images from the camcorder, into a computer.


Once stored as data files images can be used in a variety of ways, from incorporating pictures into newsletters and documents, to illustrating internet web pages. The package also includes editing software for the DVM1, and a desktop control program for their recently launched GV-PT2 video printer. Clearly youíre going to need a PC to get the most out of the DVM1, and not just any old machine, it needs to be an IBM compatible with a fast 486 DX processor, or better still a Pentium model, with at least 8 megabytes of RAM, 8 megs free disc space and Windows 3.X or Windows 95.


But weíre getting ahead of ourselves. Before we look at the PC facilities in detail a few words about the DVM1. Itís a compact DVC machine, the second one from JVC, this time with a 2.5-inch fold-out colour LCD screen instead of a conventional viewfinder. The general specification is quite similar to the ground-breaking DV1. It has a very good range of creative facilities, that includes manual exposure control, digital effects and advanced editing features. Itís a delightful machine to use, though the image on the LCD screen can sometimes be difficult to see in very bright light. Thereís plenty of useful extras, like a self-timer, image stabiliser, digital zoom with up to 100x magnification, snapshot recording mode (with shutter sound-effects) and a 5-second recording mode. Itís easy to drive, with most routine operations and secondary functions controlled from a menu-driven on-screen display.


The DVC format is capable of outstanding picture quality, comparable with semi-pro equipment, bordering on broadcast-quality. It sounds good too, with two 12-bit 32kHz stereo soundtracks, or one 16-bit 48kHz stereo track; both compare well with audio CD, in terms of frequency coverage and lack of background noise. The machine slips easily into a coat pocket and the supplied lithium-ion rechargeable battery gives between 20 to 30 minutes of recording time.


Accompanying the camcorder is the GV-DS1 docking station. Itís a small cream-coloured box, with a slot in the top, and a set of contacts, for the DVM1. It has a full set of transport controls, plus a sprinkling of sockets around the sides, and this is where it gets interesting. The one marked Ďdigitalí connects to the PCís serial port. A cable is supplied, though itís terminated in a 9-pin D socket, we suspect a lot of people will need to get hold of a 9 to 25-pin adaptor, before it can be used.


The two main options are to use the DVM1 with the docking station, enabling the machine to be controlled directly from the PC desktop, for image capture and assemble editing. Alternatively the docking station can be used as a frame grabber, with the composite video feed coming from an external device, like a camcorder or VCR.


Loading the software from the CD ROM takes just a minute or two, using normal Windows conventions. After that itís necessary to set the Com Port and data transfer speed, then itís ready to go. There are three capture modes: Ďstep by stepí or manual, from an external source, Ďprogramí and Ďintervalí, the last two with the DVM1 seated in the docking station, or used other JLIP (see below) compatible decks. The desktop is neatly presented, to grab an image click on the capture button and a few moments later the screen displays a thumbnail  image (80 x 60 pixels), of the grab along with an index number and counter data. The program then gives the user the option to display a larger window. Up to 99 images can be captured in single session, that can be organised into an indexed Ďalbumí.


When used with a DVM1 or another JLIP controllable deck, program capture grabs frames on the hoof as it were, with the camcorder or deck playback controlled by the PC. Interval capture does the job automatically, with frames grabbed at pre-set intervals. Either way itís as well to keep an eye on the PCs hard disc; a compressed JPEG image takes up around 50kbs of space, if you choose to save pictures in the alternative bitmap file format, you need to set aside 1.3Mb per grab. Bitmap images also take a lot longer to process, typically between one and two minutes, compared with ten seconds of so for a JPEG file.  


The second piece of bundled software is a video printer and edit controller.  The editing program can be used with any JVC video recorder, with an edit/JLIP  socket, or other brands of VCR using an the optional RM-V708 or V710 multi-brand infra red remote controllers. The edit control window features a full set of source machine transport buttons, counter data, cut in/out buttons, an edit decision list (EDL) and deck mode display. There are also user-set fields for file names and comments. Scenes may be copied, moved  or deleted; all timings on the EDL can be modified, a frame at a time if required, and the completed EDL can be saved to disc.


The printer controller works with the GV-PT2 video printer, connected to the GV-DS1 by a JLIP cable, and used with either a DVM1 or an external video source. With this configuration it is not possible to print image files stored on the PC. Images can be grabbed from the video source, singly, or in 4 or 16 shots per print. Itís a relatively intuitive piece of software, thatís well laid out and simple to use.



Image capture on a PC is arguably the systemís biggest selling point. The DVM1 is where it all starts and itís worth saying right away that it easily outperforms the majority of digital still cameras, when it comes to picture quality. Video resolution is in the order of 450 lines, but the amount of detail, lack of noise and colour accuracy is excellent. Incidentally this applies to both still (snapshot) mode recordings, or still frames, taken from a moving image.


The video to PC transfer process does incur some losses though. It is significant that JVC have opted for what amounts to an analogue to digital conversion technique. The alternative route, that Sony have adopted with their digital imaging systems, is to keep image data in the digital domain. They are using the ĎFireWireí interface to connect their digital camcorders to PCs, though it is worth saying that theyíre still some way behind JVC in actually getting product to the market. A to D conversion losses are actually quite small compared with the mangling that occurs, once the image is inside the PC and up to the point it appears on the screen, and that holds true at all screen resolutions. However, that needs to be see in context. Grabbed images do look very good indeed, theyíre sharp with lots of fine detail and reasonably lifelike colours. In fact theyíre noticeably better than  most other image capture systems weíve seen, though clearly thatís down to the quality of the source image.



Camcorders and PCs do not mix easily but JVC seem to have found the right formula. This outfit succeeds on all levels; the GR-DVM1 camcorder is a fine machine, and combined with the edit control software, a very useful movie-making tool. However, with the JLIP capture accessories it is transformed into what must be one of the slickest and most flexible PC imaging systems on the market, this side of professional equipment, costing several times as much.



(*) JLIP --  joint level interface protocol

JLIP is basically JVCís answer to the Sony Control L or LANC two-way serial bus. It is used to allow devices communicate with other, carrying control signals and exchanging data. JLIP jacks are now fitted to all new JVC camcorders, some older models, some VCRs and peripheral devices, like their new video printer. Unfortunately itís not possible to say precisely which products have it since it has been an unadvertised facility on some equipment for a couple of years.  



Make/model                  GR-DVM1EK

How much?                   £2000



Lens                             f/1.6, 4.5 - 45mm

Zoom                            10x optical, 100x electronic

Pick-up device            0.3in CCD

Min illum                       14 lux            (7 lux, low-light mode)

Filter diameter            27 mm  


MAIN FACILITIES               

auto/manual focus, exposure override, fade/wipe effects, digital effects (b/w, sepia, classic movie, twilight, shutter, strobe, video echo), manual white balance, audio dub, image stabiliser, time/date recording, timecode recording, self-timer, tally lamp, frame-record, photo shooting mode,  2.5 in colour LCD viewfinder, random assemble edit (8-scenes), insert editing



2 x 12-bit/32kHz stereo PCM, 1 x 16-bit/48kHz  stereo PCM, external microphone socket, headphone socket



Sockets: composite/S-Video and audio out (proprietary), AV out, microphone, headphone (minijack), DC power in

Dimensions:                  59 x 156 x 94 mm                      

All up weight:            0.75 kg (inc. tape and battery)



Make/model                  GV-DS1

System req.                  IBM PC or compatible with 486 DX processor or higher with at least 8Mb RAM and 8Mb free hard disc space, MS Windows 3.X or 95, free serial port connection

Software included             JLIP video capture, JLIP player edit


Features                       timed or manual video capture, (640 x 480 pixels 256 colours, to 1024 x 768/16.7 million colours), camcorder control and editing software

Dimensions                   113 x 61 x 145mm




Resolution                                 440-lines

Colour fidelity                           good

Picture stability                         good

Colour bleed                              none

White balance                            good

Exposure                                   average

Auto focus                                  good

Audio performance                   good

Insert edit                                  clean



Resolution                                 very good

Colour accuracy                         good

Image stability               excellent

Ease of use                               fair



Video quality                 8

PC image quality   9

Audio quality                 8

Edit facilities                  9

Build quality                  9

Ease of use                   8

Value for money            8


Overall rating            95%



R. Maybury 1997 0204



[Home][Software][Archive][Top Tips][Glossary][Other Stuff]

Copyright (c) 2005 Rick Maybury Ltd.