本论文主要介绍了JPEG的编码和解码过程。该程序的编码部分能把一张BMP格式的图象进行JEPG编码，压缩成以二进制形式保存的文件；通过相应的解码程序又可以把图象解压缩出来。在图象传送过程中，我们经常采用JPEG格式对静态图象进行编码。JPEG基本系统是一种有损编码，无法完全恢复出原图象，信息有一定的丢失，称为有损压缩。尽管我们希望能够无损压缩，但是通常有损压缩的压缩比(即原图象占的字节数与压缩后图象占的字节数之比，压缩比越大，说明压缩效率越高)比无损压缩的高。JPEG编码先把图象色彩RBG变成亮度Y和色度Cr、Cb，它利用人的视觉对色度不敏感的特点，减少一部分色度数据，以达到压缩。 JPEG采取多种编码方式，包含有行程编码(Run Length Coding)和哈夫曼(Huffman)编码，有很高的压缩比。在编码前，先对数据进行分块，离散余弦变换（DCT）及量化，保留能量大的低频信号，丢弃高频信号以达到压缩。解码时，进行熵解码，反量化，反离散余弦变换（IDCT）。
上传时间： 2013-12-21
上传用户：coeus
1）I：初始化（Initialization）。从终端读入电文，写到tobetrans文件中，统计电文的字符集合和对应的权值集合，建立哈夫曼树，并将哈夫曼树存于文件hfmtree中。 （2）C：编码（Coding ）。利用已建好的哈夫曼树（如不在内存，则从文件hfmtree中读入），对文件tobetrans中的正文进行编码，然后将结果存入文件codefile中。 （3）D：译码（Decoding）。利用已建好的哈夫曼树将文件codefile中的代码进行译码，结果存入文件textfile中。 （4）P：印代码文件（Print）。将文件codefile以紧凑格式显示在终端上，每行50个代码。同时将此字符形式的编码文件写入文件codeprint中。 （5）T：印哈夫曼树（Tree printing）。将已在内存中的哈夫曼树以直观的方式（树或凹入表形式）显示在终端上，同时将此字符形式的哈夫曼树写入文件treeprint中。 用户界面要求设计为“菜单”方式。 修改你的系统，实现对你的系统的源程序的编码和译码（主要是将行尾符编/译码问题）。实现各个转换操作的源/目标文件，均由用户在选择此操作时指定。
标签： Initialization 初始化
上传时间： 2014-01-04
上传用户：windwolf2000
D169 Demo - DMA0 Repeated Burst to-from RAM, Software Trigger Description A 32 byte block from 220h-240h is transfered to 240h-260h using DMA0 in a burst block using software DMAREQ trigger. After each transfer, source, destination and DMA size are reset to inital software setting because DMA transfer mode 5 is used. P1.0 is toggled durring DMA transfer only for demonstration purposes. ** RAM location 0x220 - 0x260 used - always make sure no compiler conflict ** ACLK= n/a, MCLK= SMCLK= default DCO ~ 800k
标签： Description Repeated Software to-from
上传时间： 2014-01-09
上传用户：thinode
The main file in this list of programs is "vblast.m". Type "help vblast" on the command line for details.Study the coding by stepping through the program. These programs require around 5000 packets for reasonable plotting accuracy.This has been implemented for a 2x2 system. The reader can program other variations. The program has been tested on MATLAB version 6.0 and above with signal processing toolbox and communication toolbox options.
标签： vblast programs command main
上传时间： 2016-08-24
上传用户：wcl168881111111
This chapter contains sample programs for determining capacity. The reader is advised to go through the coding. The file "capacity_water.m" is for measuring the waterfilling capacity. It should be made to work with a file similar to "capacity_plot_main.m". The latter file deals with all the other capacity plots given in the book in Chapter 2. All programs are verified with MATLAB versions 6.0 and above with signal processing and communications toolboxes.
标签： determining capacity contains programs
上传时间： 2016-08-24
上传用户：yph853211
This a very simple baseband simulator for SC-FDMA system. This simulator is part of the upcoming book “Single Carrier FDMA: A New Air Interface for Long Term Evolution” (Wiley, Nov. 2008) which I co-authored with professor David J. Goodman at Polytechnic University. The purpose of this simulator is to give some concrete idea of how SC-FDMA system works. It does lack many realistic and sophisticated features such as channel coding, time-varying fading channel model, soft decision decoding, etc. Regardless, I am hoping that it will help you understand SC-FDMA which is a fairly new development in 3GPP LTE.
标签： simulator This baseband upcoming
上传时间： 2016-08-26
上传用户：小草123
This directory includes matlab interface of the curvelet transform using usfft. Basic functions fdct_usfft.m -- forward curvelet transform afdct_usfft.m -- adjoint curvelet transform ifdct_usfft.m -- inverse curvelet transform fdct_usfft_param.m -- returns the location of each curvelet in phase-space Useful tools fdct_usfft_dispcoef.m -- returns a matrix contains all curvelet coefficients fdct_usfft_pos2idx.m -- for fixed scale and fixed direction, returns the curvelet which is closest to a certain point on the image Demos fdct_usfft_demo_basic.m -- display the shape of a curvelet fdct_usfft_demo_recon.m -- partial reconstruction using curvelet fdct_usfft_demo_disp.m -- display all the curvelet coefficients of an image fdct_usfft_demo_denoise.m -- image denoising using curvelet
标签： directory functions interface transform
上传时间： 2016-08-31
上传用户：cooran
DevExpress.ExpressFlowChart.Suite.v1.37.for.Delphi.BCB.Full.Source-SSG delphi 和 BCB的源码，次空间可以帮你轻松实现流程图类的图标功能，强烈推荐！ The ExpressFlowChart is designed to help you present charts, schemes, hierarchies, and graphs of any complexity with minimal coding and programming effort. The ExpressFlowChart Suite offers all the necessary tools and elements to create dazzling interfaces limited only by your imagination and the needs of your end-users.
标签： ExpressFlowChart DevExpress Source-SSG BCB
上传时间： 2016-09-29
上传用户：363186
This project should serve as an "easy start" with embOS. All pathes are relative to the project file. You should therefor be able to copy the entire directory (including all subdirectories) to any location on your harddrive.
标签： project relative pathes should
上传时间： 2013-12-28
上传用户：王楚楚
With the advent of multimedia, digital signal processing (DSP) of sound has emerged from the shadow of bandwidth-limited speech processing. Today, the main appli- cations of audio DSP are high quality audio coding and the digital generation and manipulation of music signals. They share common research topics including percep- tual measurement techniques and analysis/synthesis methods. Smaller but nonetheless very important topics are hearing aids using signal processing technology and hardware architectures for digital signal processing of audio. In all these areas the last decade has seen a significant amount of application oriented research.
标签： multimedia processing the digital
上传时间： 2014-01-23
上传用户：xwd2010
