Network Camera Image Compression And Transmission Study

Along with the development of society, the advent of the informationage, network-based multimedia messaging are changing the way of life ofmankind, but because of the huge multimedia information itself to the imageprocessing, storage and transmission have caused insurmountable difficulties,These are extremely constrained the development of multimediacommunications, image communication has also become a bottleneck in thedevelopment, therefore, video compression and transmission technologyresearch and application of digital video solve the storage and transmissionof the key.This paper consists of four partsThe first part of video compression and transmission research anddevelopment status, the significance of issues including the development ofimage compression, image compression standards, the video compression ondata transmission.End of the 20th century, society has begun to enter the digital age, withcomputer technology, modern communications technology, microelectronictechnology, network technology and other scientific and technologicaldevelopment, network-based multimedia messaging are changing the way oflife of mankind, but because of Multimedia Information itself is enormous,the image processing, storage and transmission have caused difficulties to beovercome, although the digital image data is enormous, but the image data ishighly relevant, or the existence of redundant information. At present,computer technology brought about by the information revolution that thehuman society has entered a highly information-oriented society. Imagecompression and transmission technology in the communications systems and multimedia systems in the growing importance and, in the day-to-dayproduction and daily life, the role of national defense has becomeincreasingly significant.The second part focuses on the traditional and DCT-wavelet transformand its development, its features are described and compared .Discrete Cosine Transform (DCT) is often considered the voice andimage signals to transform the best way. In order to achieve the necessaryworks, many domestic and foreign scholars spent a great deal of energy tofind or improve the fast discrete cosine transform algorithms.Wavelet analysis is a kind of time-frequency analysis. Traditional signalanalysis is built on the basis of Fourier transform, but the use of Fourieranalysis of the overall situation is a transformation that is either entirely inthe time domain or frequency domain completely. It can not express thetime-frequency signal local in nature and the nature of time-frequencylocalized non-stationary signals precisely the most fundamental nature of themost crucial, in order to analyse and deal with non-stationary signals, andpeople Fourier analysis and the promotion of fundamental revolutionproposed and the development of a series of new signal analysis theory:short-time Fourier transform, time-frequency analysis, wavelet transform.Among them, short-time Fourier transform and wavelet transform is a resultof the Fourier transform traditional signal processing can not meet therequirements.The third part details of the two classic wavelet compression algorithm,a simulation and the experimental results are compared .Shapiro embedded in the coding algorithm Zerotree groundbreakinghistorical significance in 1993, since a new generation of zero-tree based onthe coding algorithm developed. Zerotree coding not only speed andeffectiveness, but without loss of coding efficiency can produce premise embedded code flow, support multi-bit-rate codec; In addition, in codec alsoneed training in the code book and pre-storage yards, relatively simple toachieve .EZW use subband similarity between the wavelet transform domain, alarge number of small coefficient and the effective coefficient of theorganizations and said that the better-than-PJEG effect, but there are alsosome shortcomings, there is the possibility of improving. In EZW, if the rootnode as an important factor and their descendants are non-important factorwhen they were inspected his son nodes, and are encoded. SPIHT goodsolution to the problem, at the same rate, peak signal to noise ratio hasincreased substantially.Part IV as a video compression coding is a very important applicationof streaming video transmission, and is widely used in video conferencing,video telephony, IPTV, as well as remote monitoring, etc.. In this paper, thedetailed design of a network interface design, and its main purpose is for thehardware to provide a H.264 encoder Internet access, and software toprovide TCP / IP protocol support. In view of the advantages of Ethernet inthe design of a single-chip microcomputer hardware and network interfacechip Ethernet access control programmes, while expanding SRAM memory,microcontroller software platform for the provision of adequate processingresources, the network Interface software platform designed withmulti-tasking real-time embedded operating system and network protocolstack structure, multi-task operation of the CPU utilization of the greatestplay, and modular applications. So developers can be very complicatedapplication level, so that the application's design and maintenance changedeasily.This paper is based on the AVR MCU ATmega128 and Ethernet controlchip encoder RTL8019AS low-cost network interface design, details of the hardware circuit design principle. At the same time combining real-timemulti-tasking operating system and embeddedμC/OS-ⅡlightμIPnetwork protocol stack, in the above-mentioned hardware system builtmulti-task network development platform, detailed analysis of theμC/OS-ⅡμIP and the transplant completed the RTL8019AS drivers.