图像压缩技术的研究及应用开题报告

图像压缩技术的研究及应用开题报告内容摘要：

a 10GB hard drive also can not store a few minutes of video images, it is necessary to press image data. In this paper,we investigate the method that using MATLAB Wavelet Transform for pression. Methods: The image was processed by wavelet transform, and then the information of low frenquency was retained and the information of high frenquency was home zero. Results: The quality of the first image pression was high, but the pression ratio was low. The pression ratio of the second time was higher,and the image quality was good. Conclusion: The method is simple, reliable and effective in image the puter technology and the rapid development of work technology, images, sound and other multimedia information recording, storage, transmission has been digitized, the huge amount of data brought to the storage and transmission of certain difficulties, digital image pression has bee a solution to the problem key technology. Over the last decade ,wavelet theory has bee a new direction in applied mathematics. As a mathematical tool, wavelet was quickly applied to the image and voice of many other fields. Wavelet transform is a signal of time scale analysis method, the characteristics of multiresolution analysis, and in time and frequency domain has the capacity of local signal characteristics, a fixed window size, its shape variable, time window and frequency window can change the timefrequency localization analysis, that low frequency high frequency resolution and time resolution, the high frequency part of the high time resolution and lower frequency resolution very suitable for detection of transient entrainment of the normal signal anomalies and show its ponents, so the microscope known as signal analysis. 2, Image Compression Coding Theory Coding process can be summarized as： Original image Mapping transformation Quantizer Entropy Coder data stream Mapping transformation reduces the correlation between image data， Make it more conducive to pression； Quantizer to map the data into a binary digital signal； Entropy code make that appeared on the probability of a large source of symbols assigned to the short code。 Small symbol on the probability assigned to a long code, there by reducing redundant data generated code. Data pression is divided into lossless and lossy pression. Lossless pression means that image data after pression can be pletely restored, restored the same image and original image, while lossless pression refers to the pressed image data while maintaining the characteristics of the original image under the premise of inevitable loss of part of the original image is not important information. The current image based on wavelet transform press gradually replaced the DCT and the other based on the coding technique, a new image pression international Biaozhun of choice, such as the most advanced image pression standard JPG2020 the core algorithm is wavelet transform. Wavelet Analysis Principles and Methods Wavelet analysis is currently applied mathematics and engineering disciplines in a fastgrowing new field. Wavelet is a small wave, small means it has the Decay。 wave refers to its volatility. With the increasing maturity of wavelet theory, wavelet analysis has bee very broad applications. Image processing is an important area of application of wavelet analysis, image processing has bee a useful tool. principle of wavelet transform image pression Wavelet transform for image pression the basic idea is: multiresolution deposition of the image, broken down into different space, different frequency subimage, and then pairs the image coefficients are encoded. Wavelet transform coefficient coding is the core for image pression, pression is the real coefficient quantization pression. Image after wavelet transform。