> Composite video (single yellow RCA plug), as well as RF, encodes color as textured patterns (a 3.58 MHz sine wave in QAM with variable amplitude and phase) added to a black-and-white signal
In the 1970s the BBC transmitted colour TV programmes but archived them on black-and-white film, shooting a black-and-white monitor that actually had enough bandwidth to display the 4.43MHz PAL colour carrier. Someone wrote software to decode this and recolour footage based on what they recovered. It's not great, but it's at least as good as VHS colour.
Unfortunately the only really good examples of footage captured both on film in mono and tape in colour is an episode of Top of the Pops, presented by the infamous Jimmy Savile. In a happier example they were able to recover the colour from a couple of lost episodes of Morecambe and Wise.
In the 1970s the BBC transmitted colour TV programmes but archived them on black-and-white film, shooting a black-and-white monitor that actually had enough bandwidth to display the 4.43MHz PAL colour carrier. Someone wrote software to decode this and recolour footage based on what they recovered. It's not great, but it's at least as good as VHS colour.
Unfortunately the only really good examples of footage captured both on film in mono and tape in colour is an episode of Top of the Pops, presented by the infamous Jimmy Savile. In a happier example they were able to recover the colour from a couple of lost episodes of Morecambe and Wise.
https://stardot.org.uk/forums/viewtopic.php?t=16161