The footage showed Steven Randall's former partner on the floor of her kitchen surrounded by blood-soaked towels as her two grown-up children tried to tend to her wounds.
Randall stabbed her seven times in the neck and chest with a knife taken from a block on the kitchen counter.
The footage captured her son and daughter telling officers at the scene in the house in Kingstanding, Birmingham, that they found Randall straddled over their mother with a knife in his hand.
They also told how they managed to pull Randall away and took the knife from him – but were scared he would carry on the attack using other knives in the kitchen.
However, Randall instead drove away from the house and was arrested three days later after getting in contact with his daughter.
Randall, 51, of Hartley Road, in Kingstanding, admitted attempted murder and was sentenced to 10 years at Birmingham Crown Court earlier this month.
DC Anthony Butterworth, of West Midlands Police's Public Protection Unit, said: "Although the motive for this horrifying attack remains unclear, the images and first disclosure testimony from officers’ body cams proved so powerful that Randall admitted the charge, thus saving his family the trauma of having to relive the attack in court.
“The damage Randall inflicted in his attack initially left his victim unable to speak, but following surgery her voice has since returned.
“We hope this substantial sentence will now allow her, and the rest of her family, to move on with their lives.”