Transmission of images over general packet radio services using advanced wavelet image codecs and digital signal processor chips

We develop a wavelet-based codec using a low-cost and low-energy-consuming 16-bit fixed-point digital signal processor (DSP). The target application is designed to grab an image from a camera, code the image using a wavelet-based codec, and send a coded file over a wireless global system for mobile communications/general packet radio services (GSM/GPRS) network. Since the channel capacity of the GSM/GPRS network is limited, a DSP with a relatively low computational power is sufficient to implement an image codec. A trade-off is made between the complexity and the efficiency of the wavelet-based image coder. Any implementation issues concerning the wavelet transform and entropy coding are discussed. Lifting schemes for a 9-7 and a 5-3 filter bank are used. The novel ordering of bit-plane bits is presented. The proposed codec is comparable with a JPEG2000 codec in the rate-distortion sense. The experimental results show that the implementation of JPEG 2000 on the presented platform runs 60% slower than the proposed codec. The coded file is transmitted over a wireless network using Internet protocol/user datagram protocol/trivial file transfer protocol (IP/UDP/TFTP).