Daniel Taylor, 31, possessed more than 300,000 indecent images, including a large number considered the most extreme, Bradford Crown Court was told.

Taylor had 47 devices including hard drives, phones, memory sticks and a laptop to store the pictures.

Some of the sick images he downloaded included ones depicting torture of children aged between five and 11 and rape of toddlers.

Taylor also downloaded a manual from the internet detailing how paedophiles could abuse children from birth to eight-years-old, without leaving evidence of abuse.

Taylor, who worked as a gutter fitter, used a covert digital video camera disguised as a cigarette lighter to twice film himself sexually abusing a baby girl.

None of the charges relate to Taylor’s children.

Judge Rodney Grant said Taylor must serve a minimum of three years, minus time spent in custody, before he can be considered for release.

He said a report described Taylor as “opportunistic and predatory” and warned he posed a danger to children in the future.

Father-of-two Taylor, of Heights Drive, Farnley, Leeds, pleaded guilty to 27 charges, including making and possessing indecent images and sexually assaulting a baby.

He also asked for three other charges to be taken into consideration.

During a search of his property, officers discovered a tin in the kitchen containing the covert camera disguised as a lighter which was capable of capturing and storing video images.

Taylor encrypted his web of computers and storage devices, but police used state-of-the art technology to break his codes and access the material.

The court was told the offences were so serious because of the amount of material involved and the horrific nature of the content, with 328 images graded at level 5 – considered the most extreme.

More than 5,000 were graded at level 4.

Judge Grant said Taylor posed a danger and an indeterminate sentence was his only option.

He also ordered him to sign the sex offenders register for life and to comply with a sexual offences prevention order.