Filner was booked in the jail at 7:11 a.m. Saturday to complete fingerprinting and a mug shot.
He was released at 8:57 a.m., U-T San Diego reported.
The booking process was initially set for Sunday.
Earlier this week, Filner pleaded guilty to a felony count of false imprisonment and two misdemeanor counts of battery.
The charges followed an investigation into sexual harassment allegations that were made during his tenure as mayor.
Filner's plea agreement details three years of probation, three months of home confinement and other conditions.
His sentencing is set for Dec. 9.
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