The Video CD – better than DVD?

David Dorn has been examining DVD’s baby brother as a medium for handling Digital Video, and is pleasantly surprised at the quality.

Anyone buying a video camera these days is likely to be buying a Digital one, for all sorts of reasons. Not least is the fact that the quality of picture on a normal domestic television is nothing short of superb, and all but unobtainable with normal analogue domestic camcorders.

Archiving digital video, though, is quite another matter. Most folks connect their cameras up to their normal VHS recorders and transfer the movies to VHS tape – effectively halving the resolution they’re viewing the footage at, and thereby cutting the quality enormously. But there is another way.

VCD – or Video CD – can be at least as good as VHS and on a par with SVHS if you go about doing the job properly. Granted, you can write to DVD these days and play them back on your DVD player, but for most of us the cost of the DVD writer is still prohibitive. VCDs will play on the vast majority of DVD players, and almost all players that can read a CD-R or CD-RW.

So how do you go about creating DVD’s baby brother? The process is not that complex, although it is somewhat time consuming. The first step is to get the footage onto your PC. That requires a Firewire adapter and lead, and some software – and is covered in more depth here. So far, quite simple really.

It’s worth noting that you’ll need roughly 12 - 16GB of hard disk space for every hour of digital video – and since a VCD can hold up to 74 minutes of movie, we’re talking about more or less a tape’s worth fitting onto a shiny silver disk.

Once the footage is in your PC, you’ll want to edit it to either split it into coherent scenes and get rid of any dross or join together clips from different tapes to produce a one-shot program. So far, nothing’s radically different from what you’d do before you write the movie back out to digital tape.

Compression

The next step, though, is very different. If you’re working in the digital tape domain, you are constantly working with file in its native format. But because you’ll be writing to VCD, which has a 650MB limit, (700MB on an 80 minute CD-R), that 16gb has to be compressed down – and here’s where the fun begins.

The file format of video footage on a VCD is MPEG1 – a 352x288 pixel resolution at a bitrate of 1151929 bits/sec. That compares to VHS at a line count of 200 lines (88 lines less than MPEG1), so the potential quality is higher on the digital format. Unfortunately, it’s not as high as DV format, which gives 720 pixels per scan line at 625 lines – at better than 5MB/sec.

That DV resolution has to be compressed to fit not only the physical dimensions of the MPEG1 format, but also the much reduced bitrate – which is where you’ll need a compression/preparation tool.

Commercial products such as MGI’s VideoWave 5 can produce the required file format, and there are numerous shareware and freeware programs that perform conversion from one format or another to MPEG1 – check out our Top Software library for a couple that work well.

Whichever route you choose, the compression stage cannot be bypassed – and this is where the time factor suddenly shows itself. Even on a 1.7GHz Pentium 4 equipped machine with bags of RAM, the process is as near as dammit real time – that is to say 15 minutes of video encodes in roughly 15 minutes.

Writing the VCD

Once your video stream is compressed to the correct format, you’ve then got the task of writing the VCD. Owners of either Nero Burning ROM or Roxio’s Easy CD Creator have VCD making capability built right into their software. Roxio’s is wizard based, and, in truth, is not all that easy to get to grips with, unless you’re simply producing a single movie – creating DVD-like menuing systems takes some practice.

The results, though, are pretty darned good. So far, I’ve created three VCDs of varying subject types, and the video has easily been of better quality than I’m used to from VHS tapes. I’d also say that it’s pretty much on a par with SVHS, but isn’t quite as good as DVD. That said, it’s a whole lot cheaper to produce a VCD than it is to produce either a DVD +RW or an SVHS tape, and subsequent duplication of VCDs for distribution to the family is a simple (and very quick) matter of copying the original VCD – and there’s absolutely no loss of quality.

Is it worth it?

A resounding yes. Consider this: MiniDV tapes are small and easily lost – they’re not particularly cheap, either – and, like all magnetic media, they’re subject to corruption by magnetic fields. A VCD is recorded to a blank CD-R (or RW, if you might want to erase it), and recordable blanks are very cheap to buy. Child copies from VCD are identical to the previous generation, and are far less likely to suffer corruption from outside influences, scratches, obviously, excepted. With a decen speed CD burner, a full VCD can be copied in a matter of minutes anyway, so it’s very simple to create an archive copy and a copy for general use.

A well-used tape will, eventually, wear out. The same cannot be said of a VCD.

So, if you’ve got a digital camcorder and a CD burner, what are you waiting for? VCD was tailor made for transferring a full Mini-DV tape to – get started!

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David Dorn