Image caption Sally James from Tiswas and Basil Brush - both shows are to be preserved

Thousands of British TV programmes are to be digitised before they are lost forever, the British Film Institute says.

Anarchic children's show Tiswas and The Basil Brush Show are among the programmes in line for preservation.

The initiative was announced as part of the BFI's five-year strategy for 2017-2022.

"Material from the 70s and early 80s is at risk," said Heather Stewart, the BFI's creative director.

"It has a five or six-year shelf life and if we don't do something about it will just go, no matter how great the environment is we keep it in.

"Our job is make sure that things are there in 200 years' time."

Image caption Vision On's Tony Hart and Pat Keysell

The BFI has budgeted £13.5m of Lottery funding towards its goal of making the UK's entire screen heritage digitally accessible.

This includes an estimated 100,000 of the "most at-risk" British TV episodes and clips held on obsolete video formats.

The list includes "early children's programming, little-seen dramas, regional programmes and the beginnings of breakfast television".

Tiswas became a cult favourite after it began on ITV station ATV in 1974. Its presenters included Chris Tarrant, Sally James, Lenny Henry, Bob Carolgees and Spit the dog - plus regular appearances from the Phantom Flan Flinger.

Basil Brush, the fox puppet invented by Ivan Owen in 1963, attracted audiences of up to 13 million during his 1970s heyday on BBC One.

TV shows on the preservation list

Image caption Michael Barratt presenting Nationwide in 1970

Children's:

How (1966-1981, Southern Television) - Educational programme whose presenters included Jack Hargreaves and Fred Dinenage

(1966-1981, Southern Television) - Educational programme whose presenters included Jack Hargreaves and Fred Dinenage Vision On (1970s, BBC One) - Art series for deaf and hearing-impaired children, presented by Pat Keysell and Tony Hart

(1970s, BBC One) - Art series for deaf and hearing-impaired children, presented by Pat Keysell and Tony Hart Shang-a-Lang (1975, Granada) - Music show with the Bay City Rollers

Comedy:

Do Not Adjust Your Set (1967-69, ITV) - Show with Michael Palin, Terry Jones, Eric Idle, David Jason, Denise Coffey and The Bonzo Dog Doo Dah Band

(1967-69, ITV) - Show with Michael Palin, Terry Jones, Eric Idle, David Jason, Denise Coffey and The Bonzo Dog Doo Dah Band At Last the 1948 Show (1967, ITV) - Programme featuring John Cleese, Graham Chapman, Marty Feldman, Tim Brooke-Taylor and Aimi MacDonald

Dramas and documentaries:

Second City Firsts (1973-78, BBC) and Rainbow City (1967, BBC) - Showcasing early work by black and Asian TV writers

(1973-78, BBC) and (1967, BBC) - Showcasing early work by black and Asian TV writers The Bandung File (1985-91, Channel 4) and Eastern Eye (1982-85, Channel 4) - As well as the channel's entire first week of broadcast in November 1982

(1985-91, Channel 4) and (1982-85, Channel 4) - As well as the channel's entire first week of broadcast in November 1982 Nationwide (1969-83, BBC) - an early evening current affairs show, which is held on an "exceptionally rare" video format

Ms Stewart said one of the biggest problems was the shortage of equipment to play the outdated tapes.

"The whole infrastructure in relation to video is just disappearing," she said.

"There are technicians who want to retire. We can't let them go until we've got this stuff off these two-inch and one-inch formats.

"There's a limited pool of people who know how to do it. There's a limited pool of machines. The guy who runs the archive is collecting the stuff from car boot sales."

Image copyright BFI Image caption The BFI National Archive in Berkhamsted was established in 1935

Many of the titles are kept at the BFI's National Archive in Berkhamsted, Hertfordshire.

The issue for the BFI, Ms Stewart added, was also to do with freeing up storage space.

"We have a whole vault which is wall-to-wall video. If we digitised it, it would be in a robot about the size of a wardrobe," she said.

She revealed that the digitisation of BBC's The Wednesday Play (1964-1970) had already been completed.

Image copyright Derek Batey Enterprises Ltd Image caption Derek Batey launched Mr and Mrs in 1967

Border Television's popular marriage quiz show Mr and Mrs, which Derek Batey began hosting in late 1960s, is also in line for preservation.

Ms Stewart said: "In 200 years, Mr and Mrs needs to be there so audiences of the future can enjoy it."

The BFI's five-year strategic plan, announced on Tuesday, will see the investment of almost £500m for UK film.

Its plans include funding for films not aimed for cinema release, devolving more decision making outside London and promoting greater diversity within the industry.

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