How the old images were created

At the time when the older pictures were digitised, my RISC OS computer only supported 256 colours, as it was an old machine.

In order to provide the highest possible quality, the episodes were recorded onto VHS video and later digitised with the Typhoon TV capture card fitting in my Compaq PC. While the processor (originally 75MHz, clocking at 100MHz) and PCI bus were not able to provide a full sized image, it made a nice half-size image in 16 million colours.

Unfortunately the card grabs slightly more than the normal 'visible area', so you will see a bit of weirdness down the vertical edges of the picture. This is, for want of a better description, 'workspace' used by the VideoCrypt scrambling system. Basically, each line of the picture may be cut at one of 256 different places, and stored in any order, differing on each line. A horridly complicated mathematical process can reconstruct the image, assisted by a smartcard which holds the key to the correct decoding sequence.
The extreme left and right sides of the picture do not appear on a normal TV, so you don't notice this in effect. But the Typhoon digitiser does.

The images were manipulated totally within the Windows95 environment. The digitiser software, stupidly, exported single frames as .DIB files. PaintShopPro was the only software I found that recognised these. So I set PSP to simply batch convert the images to JPEG files.

The older pictures are:

The touched by an Angel thumbnails were created with ChangeFSI from RISC OS.


You may notice some slight horizontal interference in the picture (like the picture is comprised of lines which don't totally match). This is due to the picture having been 'scrambled' with VideoCrypt. It's just something I've become used to.
The original (broadcasted) picture looks like...

crypt.jpeg; 20K

If you're interested, the picture is the airplane landing in front of the house at the end of the movie "Forever Young". That's what was on, as I was writing this... :-)

Click here if you are would like to know more about VideoCrypt.



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