Abstract: Coding based on transform domain is widely used in image compressing.But the rapid development of wavelet gives a stern test to traditional DCT.The DCT algorithm also has new advances: after reorganizing coefficients or embedding,DCT’s property is similar to wavelet’s.With its own fine characteristics DCT still hold broad application prospects in the image compression.In fact,primary factor for the transform domain compression lies in the quantizer and the entropy encoder.DCT and DWT have their ...

Key words: transform domain； discrete cosine transform(DCT)； discrete wavetet transform(DWT)；