Keith and Caroline Baker kept their victim in a squalid room without carpet, a light bulb, bedclothes or curtains, for eight years.
Police rescued her from the house in Craigavon, County Armagh, in 2012.
The woman, who had severe learning difficulties, was emaciated and had only a single tooth left in her mouth.
She weighed just six stone (38kg) when she was found.
▪ ‘Sex-slave’ woman ‘too scared to leave’
Sentencing Keith Baker to 15 years in jail and a further five years on licence after his release, Judge Patrick Lynch QC described the 61-year-old as a “Svengali-type figure” whose wife was a “pawn doing his bidding”.
The couple last month pleaded guilty to a catalogue of charges, including sexual activity involving penetration and causing a person with a mental disorder to engage in sexual activity.
Keith Baker, who was raised in Guernsey and lived most of his life in Kent, was also charged with rape and indecent assault.
His 54-year-old wife received a three-year sentence, 18 months of which will be spent in jail, with the remainder on licence.
“It is not easy to understand how these individuals have so lost their moral compass that they could subject an individual, who clearly exhibited serious mental defects, to mistreatment in sexual terms, depriving her of any dignity and even the most basic of living standards,” said the judge.
Their Drumellan Mews home had been described in court as a “house of horrors”.
Their vulnerable victim was kept captive in a room with the handle having been removed from the door and a camera suspended from the ceiling.
She was not registered with a GP or a dentist and was not on the electoral register: neighbours did not even know she was in the house.
From the court: Gordon Adair, BBC News NI reporter
Keith and Caroline Baker first met when they worked for the Salvation Army.
But their treatment of their helpless, traumatised victim was anything but charitable.
Sitting in a wheelchair outside the dock, Keith Baker slumped as the court heard graphic details of the abuse films he created.
His wife stood inside the box, eyes to the floor, even as prison guards led her away in handcuffs.
The only toilet she had access to was overflowing with human waste.
The couple had taken the woman from her home in England in 2004; she was reported missing by her husband.
She was found by police in Northern Ireland eight years later after another woman, Mandy Highfield, contacted officers.
Ms Highfield had also lived with Keith Baker and was the mother of four of his children.
When detectives searched the house they found videos of the Bakers abusing their victim.
The images showed how she had deteriorated from being relatively healthy to malnourished over the years she was held inside the house.
Speaking after the sentencing, the head of the Police Service of Northern Ireland’s public protection unit said the Bakers had carried out “an appalling litany of crimes”.
The abuse to which they subjected the woman was “filmed for their own sexual gratification”, said Det Ch Supt George Clarke, adding that they had stolen her basic human rights.
The case had been a “difficult, challenging and emotional” one for the police officers involved, he added, but that “pales to insignificance” to what the woman was forced to endure.
“What [she] went through is unimaginable – it doesn’t bear thinking about what this victim endured over the thousands of days she was kept prisoner,” said Mr Clarke.