Photoshop

To OCR text on a coloured background.

Scan @ 300 DPI in colour
Select > Colour Range > Sampled Colour
Click on lettering not background.
Copy
Ctrl. N to make a new file
Paste into the new file
Image > Mode > Greyscale
Image > Mode > Bitmap
Adjustments > Threshold - Select 50%
Save as = Bitmap

OCR bitmap