Compression and transmission of facial images over very narrowband wireless channels
Law enforcement officers on mobile duty are often confronted with ID authentication of subjects entailing the transmission of a driver's license picture over wireless channels that are very narrowband. To access mug shots in a reliable and timely manner, a real time compression and decompression method with high compression ratios is required at the server database and the mobile client unit. The presented technique minimizes the size of the data sent over the channel by locally storing common features of the human face in the client computers. Pre-processing of server database images, such as facial feature extraction, are used to extract these common facial features, obtained via ravines and image singularities. The implemented file transfer protocols are based on basic TCP/IP client-server models and make use of socket programming. Experimental results show a 5/spl times/ improvement in transfer time over typically saturated channels.