At low bit rate

the images encoded by standard wavelet coders inevitably undergo the so called ringing phenomena near sharp edges. A low bit rate image compression algorithm based on edge adaptive wavelet transform is proposed. At the encoder side

firstly the strong edges of an image are detected and encoded as additional information; Then the wavelet transform is carried out in such a way that no filtering over previously detected edges is performed; Finally

the wavelet coefficients are encoded by the wel known EBCOT algorithm. Especially

a new method to overcome the boundary effects in wavelet transform of segmented data is proposed. Compression examples show that the edge adaptive wavelet transform achieves good reproduction of sharp edges even at very low bit rate. Because of the additional information

the PSNR of the compressed images is typically slightly lower than that of standard coders

but the subjective vision impression is improved significantly.