Review Pinnacle PCTV Pro
Building A PC-Based Personal Digital Entertainment Centre
A project diary describing the process of building a PC-based home entertainment center based on regular off-the-shelf computer components and software.

Back to the Project's Main Page

Review: Pinnacle PCTVpro Tuner/Capture Card - Software
The software provided with the PCTVpro hardware offers an awful lot of functionality for such a low-cost product.
Capturing Video
 
As mentioned in the body of this page, capturing video to disk in realtime places quite a load on your average PC.

There are generally two ways to do it:

Compress on the fly:
In this case, the captured video is compressed into its final format (usually MPEG) before it's written to the disk. This requires a very powerful CPU but reduces the amount of disk storage and the speed of the disk drives required.

Due to the huge amount of processing power required to perform this "on-the-fly" compression, the resolution and quality of the captured video is often compromised.

Compress after capture
In this case, the data is captured with no (or only minimal) compression before it is written to disk. This technique places far less load on the computer's processor and will allow capturing at VHS/VCD resultions on a machine as wimpy as a P2/400.

The flipside is that you will need a large HD since the machine will be storing a gigabyte of data every 9-10 minutes or so.

Once captured, the file created will then need to be compressed into its final format and that can take up to four hours processing for every hour captured.

According to the brochure you can watch TV, digitally record your favourite programs with realtime MPEG1 or MPEG2 compression then burn them at to VCD, SVCD or DVD resolution onto CDR or CDRW media.

If your computer's fast enough it even promises to provide a timeshift function just like the Tivo and Replay TV boxes.

Of course, as most of us find out at an early age, there's sometimes a world of difference between the promise and the reality -- and so it is with the PCTVpro's software package.

Yes, you can use it to watch TV on your PC. Yes it does allow you to record TV programs to your hard disk. Yes, you can burn those programs to CDR/RW media -- but not quite as nicely or smoothly as it should.

Visit the sponsor
If you'd like your own system, it is recommended that you purchase the parts, or a ready-configured version from the project's sponsor.


Watching TV is okay and even when the picture is routed through a TV-out connection onto the 29" screen of my Sony TV you'd be hard pressed to spot that it was coming from a computer and not the TV's own tuner.

It's really only once we try doing the fun stuff that things begin to turn to custard.

To understand the main problem it's important to realise just how processor-intensive good video compression really is. Performing realtime MPEG encoding of any quality requires a lot of grunt and is usually best done by a dedicated MPEG processor on a separate card.

However, a dedicated hardware-based MPEG encoder is not cheap, costing many times more than the PCTVpro card itself so instead, the PC's own processor must shoulder the compression burden.

In order to make this practical, the MPEG routines used by the Pinnacle software are not particularly impressive in respect to the quality of image they produce.

There's quite noticeable pixelation on both MPEG1 and MPEG2 recordings - particularly if you stick to the standard bit-rates. Comparing the recordings made by the Pinnacle software with those created by a good hardware encoder or programs that don't try to operate in realtime is a real eye-opener.

This video quality problem also affects the timeshift mode since what you're doing there is effectively watching a recording made a few seconds (or minutes) earlier.

Rapid movement prodcues image tearing and pixelation that are quite distracting and, although you tend to become acustomed to this after a while, it's still disappointing and irritating.

Next: Pinnacle PCTVpro Review, The Software, part 2

Back to The main project page


Published and © 2002 by Bruce Simpson and Aardvark Net Publishing. All rights reserved