Research Of Underwater Acoustic Image Coding Technology Based On Wavelet Transform

With the rapid development of computer technology and information technology,human needs for information have been met.At the same time,the increasing amount of data has also brought pressure on storage and transmission.Among them,the image-based multimedia information carries a large amount of information and intuitive performance,but the amount of data is large,and there are certain problems in storage and transmission.The improvement of image coding technology can effectively solve the above problems.In the field of ocean exploration,with the wide application of underwater acoustic technology,the amount of underwater acoustic image data acquired by various underwater detection equipment has grown rapidly.Due to the complex marine environment and the limited underwater acoustic channel bandwidth,the underwater acoustic image needs to be compressed Encoding can better transmit and restore images.Because of its excellent time-frequency analysis capability and multi-resolution analysis characteristics,wavelet transform can be applied to image compression,and it can meet the high compression ratio while ensuring the reconstruction quality.Therefore,this article studies the underwater acoustic image coding technology based on wavelet transform.First of all,the background,significance and development status of the research are summarized,and the basic theory of image compression coding is introduced,including the feasibility,basic methods and classification of image coding,underwater acoustic image compression coding and image compression quality evaluation standards.Secondly,it focuses on the basic theory of wavelet transform,analyzes the characteristics of wavelet transform image through experimental data,introduces the basic principle steps of wavelet transform coding,and analyzes some issues that need to be paid attention to when wavelet transform is used in image coding.Then,the basic ideas,principles and implementation process of EZW algorithm and SPIHT algorithm are studied,and the performance analysis and comparison of SPIHT algorithm from four aspects: average code length,compressed image type,wavelet decomposition series and wavelet base selection.Based on the classic SPIHT algorithm,the visual characteristics of the human eye are improved,the wavelet coefficients are visually weighted,and the important coefficients are preferentially encoded by adjusting the coding order to improve the quality of the reconstructed image.Experiments show that the VIF value of the reconstructed image obtained by the improved algorithm has been significantly improved,and the image quality is better.Finally,according to the characteristics and compression requirements of underwater acoustic images,combined with the edge detection technology and the coding idea of the region of interest,the adaptive SPIHT algorithm based on HVS is further improved to achieve efficient compression of underwater acoustic images.Experiments show that the improved algorithm can ensure the completeness of the edge information of the recovered image and achieve high-quality reconstruction of the region of interest in the underwater acoustic image.