An image is partitioned into a foreground area, a background area, and optionally a transitional area. The partitioning may be pre-defined, or it may be based on user inputs and configuration data. The partitioning may also be refined based on an initial partitioning. Blur measures are determined respectively for the partitioned areas. A blur measure for the whole image can then be determined from a weighted average of the blur measures for the partitioned areas. The blur measure for the image can be used in a video quality monitor.