Low Complexity Video Encoding and High Complexity Decoding for UAV Reconnaissance and Surveillance

Conventional video compression schemes such as H.264/AVC use a high complexity encoder with block motion estimation (ME) and a low complexity, low latency decoder. However, unmanned aerial vehicle (UAV) reconnaissance and surveillance applications require low complexity encoders but can accommodate high complexity decoders. Moreover, the video sequences in these applications often primarily have global motion due to the known movement of the UAV and camera mounts. Motivated by this scenario, we propose and investigate a low complexity encoder with global motion based frame prediction and no block ME. For fly-over videos, our encoder achieves more than a 40% bit rate savings over a H.264 encoder with ME block size restricted to 8 × 8 and at lower complexity. We also develop a high complexity decoder based on Kalman filtering along motion trajectories and show average PSNR improvements of up to 0.5 dB with respect to a classic low complexity decoder.