I ve written some many years ago dynamic Huffman algorithm to compress and decompress data. It is mainly targeted to data with some symbols occuring more often than the rest (e.g. having some data file consisted of 3 different symbols and their total number of occurence in that file s1(1000), s2(200), s3(30) so the total length of file is 1000+200+30=1230 bytes, it will be encoded assigning one bit to s1 and 2 bits to s2, s3 so the encoded length will be 1*1000+2*(200+30)=1460 bits=182 bytes). In the best case the file consisted of just one symbol will be encoded with compression ratio as 1:8. Huffman coding is used in image compression, however in JPEG2000 arithmetic codec is imployed.
标签： decompress algorithm compress Huffman
上传时间： 2016-05-16
上传用户：aysyzxzm
Matlab is an ideal tool for simulating digital communications systems, thanks to its easy scripting language and excellent data visualization capabilities. One of the most frequent simulation tasks in the field of digital communications is bit-error- rate testing of modems. The bit-error-rate performance of a receiver is a figure of merit that allows different designs to be compared in a fair manner. Performing bit-error-rate testing withMatlab is very simple, but does require some prerequisite knowledge
标签： communications simulating scripting digital
上传时间： 2014-01-02
上传用户：plsee
Recognizing its importance is only the fist step to advocate invetion or innovation， and some effective measures should be taken for it. For one thing， our authority should continue to enlarge the recruit of graduate. For another， the conditions of scientists and skilled workers should be further improved. Only in this way， can “the soul of our nation” be fully embodied and our nation have a brighter future.
标签： Recognizing importance innovation advocate
上传时间： 2016-05-26
上传用户：水中浮云
Library and command line program for Huffman encoding and decoding both files and chunks of memory. The encoder is a 2 pass encoder. The first pass scans the data and builds the Huffman tree. The second pass encodes the data. The decoder is one pa
标签： and encoding decoding Library
上传时间： 2016-06-01
上传用户：zhaiye
This project shows how to use the IOKit notification mechanism to register to be notified when devices come and go. It uses the Cypress/Anchor EZ-USB chip. (Look at the following example for another way to get notified when a device is unplugged).
标签： notification mechanism notified register
上传时间： 2013-12-01
上传用户：zhuimenghuadie
This file contains a C++Builder 4 project called SimplyChaos-X ver 3.1 (SCX31). SCX31 is an encryption tool. I designed it as my graduation paper work. SCX31 is a symmetric stream cipher built on chaos function, one time pad cipher and inspiration from Ground Effect (aviation). The key length can be up to 40 characters (320 bits).
标签： SimplyChaos-X SCX contains Builder
上传时间： 2016-06-07
上传用户：nanshan
This paper presents a low-power asynchronous implementation of the 80C51 microcontroller. It was realized in a 0.5 µ m CMOS process and it shows a power advantage of a factor 4 compared to a recent synchronous implementation in the same technology. The chip is fully bit compatible with the synchronous implementation, and timing compatible for external memory access. The circuit is a compiled VLSI-program, using Tangram as VLSI-programming language and the Tangram tool set to compile the design automatically to a standard-cell netlist. This design approach proves to be powerful enough to describe the microcontroller and derive an efficient implementation. Further, it offers the designer the possibility to explore various alternatives in the design space.
标签： microcontroller implementation asynchronous low-power
上传时间： 2016-06-07
上传用户：冇尾飞铊
JLAB is a set of Matlab functions I have written or co-written over the past fifteen years for the purpose of analyzing data. It consists of four hundred m-files spanning thirty thousand lines of code. JLAB includes functions ranging in complexity from one-line aliases to high-level algorithms for certain specialized tasks. These have been collected together and made publicly available for you to use, modify, and --- subject to certain very reasonable constraints --- to redistribute. Some of the highlights are: a suite of functions for the rapid manipulation of multi-component, potentially multi-dimensional datasets a systematic way of dealing with datasets having components of non-uniform length tools for fine-tuning figures using compact, straightforward statements and specialized functions for spectral and time / frequency analysis, including advanced wavelet algorithms developed by myself and collaborators.
标签： co-written functions the fifteen
上传时间： 2014-01-26
上传用户：hjshhyy
用fpga实现的DA转换器，有说明和源码，VDHL文件。 A PLD Based Delta-Sigma DAC Delta-Sigma modulation is the simple, yet powerful, technique responsible for the extraordinary performance and low cost of today s audio CD players. The simplest Delta-Sigma DAC consists of a Delta-Sigma modulator and a one bit DAC. Since, both of these components can be realized using digital circuits, it is possible to implement a low precision Delta-Sigma DAC using a PLD.
上传时间： 2016-06-10
上传用户：bjgaofei
linux下用C语言写的聊天程序！/*BUG and NOTE: Not join protect to Shared Memory Segments,example Semaphore Arrays. Not check the parameters validity. When transmit may be error. If the client program no right exit,others cannot know,the service program shouldbe check the client program whether exist timing. The program when exit(), it do not delete the Shared Memory Segments,you maybe use atexit() but the program have some processes. When one process is exit(),others is continue. The service program s action is few. And so on. */
标签： Semaphore Segments example protect
上传时间： 2014-01-25
上传用户：xhz1993
