A current picture partitioned into a plurality of partitions is received and encoded by determining a total target number of encoded bits for the current picture to avoid overflow or underflow of a video buffer verifier (VBV) maintained by an encoder. The encoder determines a local target number of encoded bits for each partition of the current picture, in accordance with the total target number. A plurality of partition encoders encode each partition, respectively, in accordance with the local target number for said each partition, wherein each partition encoder maintains a local VBV having a local VBV fullness, to monitor local underflow or overflow conditions.