Chroma dots

Chroma dots are visual artifacts caused by displaying an unfiltered PAL analogue colour video signal on a black-and-white television or monitor. They are commonly found on black-and-white recordings of television programmes originally made in colour. Chroma dots were once regarded as undesirable picture noise, but recent advances in computer technology have allowed them to be used to reconstruct the original colour signal from black-and-white recordings, providing a means to re-colour material where the original colour copy is lost.

Example of the chroma dot reconstruction:

• Example of the chroma dot reconstruction (please view images at 100%)
• Original picture
• Black and white picture with chroma dots
• Quadrant calculation for Colour reconstruction
• Reconstructed Colour picture (reconstructed using software written by Richard Russell)