I re-read the following:
Y = 0.299R + 0.587G + 0.114B
A light bulb went on, and I realised I'd been completely wrong in the way I was scaling my Red, Green and Blue images before combining them. This also meant that the Gaussian Blur step was not needed.
What I needed to do to with the colour channel images I made from my initial 720 x 576 images was to horizontally scale them in The GIMP by following amounts:
- Red to 720 x 0.299 = 215 pixels
- Green to 720 x 0.587 = 423 pixels
- Blue to 720 x 0.114 = 82 pixels
Here's the logo I created for my friend Greg Taylor's company before:
Before image. Can you spot Emily Moore?
And here it is after using this revised method:
Now with PAL - click to enlarge the images
I'm sure I'll come back to this again, but I'm finding it interesting.