| Compression of images has brought great convenience to all kinds of application, Digital Cameras, Remote Sensing, Fax, and Electronic Business and other fields of Medical Application. Compression of images technology becomes more and more mature and diversified. The wavelet transform, a mathematical way, in recent years, is widely used in various aspects; Such as image segmentation, image classification, image texture, wavelet transform of multi-resolution; and in the frequency domain, time domain it enables partial advantage of wavelet image compression. It has also been rapidly developed at the same time. Overall, the wavelet transform used in image compression research focused mainly on two aspects: First, the different kinds of wavelet transform used in image compression, such as different kinds of wavelet packet wavelet transform image compression effect; Second, wavelet transform used on the quantization of image coefficients and coding, such as zero-tree coding and some other methods for improvement. These methods and scientific experiments are a good proof of the advantages of wavelet transformation used on image compression.However, a particular shape of this iris image, wavelet image compression effect can be further improved. Specialized for image shape of the current research is not much, research to the iris feature to change the direction of the wavelet transform is not much either; this paper presents a tangential-radial wavelet transform on the feature extraction of image compression and gives more discussion on the efficiency image compression.This paper describes the coding classification of image compression and some prevalent of the international standards from various perspectives such as statistical coding, transform coding, linear predictive coding and vector quantization coding; It introduces the main international coding standard methods: JPEG compression standard, JPGE2000 compression standard, MPEG series of moving image compression and H2.261 series. The main purpose of this study is to explore the application of tangential-radial wavelet transform on the field image compression, which includes the methods of storage format transformation from matrix format of the image pixels into polar coordinates stored image pixel. It also discusses in the compression effect of tangential-radial wavelet transform used on frequency domain, and the effect on the image of the round symmetrical transformation. Further described is the improvement of radial-tangential wavelet over the Ordinary wavelet transform on image compression.Secondly, we further introduce the way of tangential-radial wavelet on image compression and discuss more about the theoretical introduction; we also conclude iris recognition research background, iris recognition processing, and experimental comparison result. Our innovation is that tangential-radial wavelet can achieve better image effect after decompression after. |
