Comparison of adaptive prediction and quantization schemes in intraframe video signal coding by subband decomposition

摘要

This paper deals with Pseudo-QMF sub-band coding of color TV signals basedudon DPCM schemes with scalar quantization . The coding scheme includes twoudoperating modes. The first one, named intraframe and presented here, is used toudcode the beginning of a sequence and to process the scene cuts . The second oneudis an interframe coding mode, which allows to take into account the temporaludcorrelations. The proposed methods are based upon predictive coding system andudscalar quantization and the objective is to get an excellent visual quality of theuddecoded images . First, we proposed three sets of adaptive prediction functionsudand compared them . Then we developed three adaptive quantization schemesudwith differents complexity of adaptation. All these methods have been tested andudcompared in terms of entropic gain over PCM coding scheme and also in termsudof locally and globally visual quality . Finaly we present our results in terms ofudbit-rate, peak SNR and visual quality of reconstructed images.