An region of interest based video compression for indoor surveillance

Motion detection is an important part in video surveillance. When it is combined with video compression and transmission, the bit rate can be further minimized under a fixed background. In this paper, we show that under indoor circumstance, most of the macro blocks (MB) in I frame are redundant in the sequence. In H.264, standard pulse code modulation (PCM) is chosen to encode MBs by writing pixel values directly into the bit stream. Experiments show that surveillance sequence hardly uses this PCM in encoding, leaving us an interface to encode background MBs with. The foreground is encoded normally using H.264, which causes little degradation in video quality while the bit rate is dramatically decreased. In decoder, PCM MB is decoded accordingly.