提出一种基于视觉特性的图像摘要算法，增大人眼敏感的频域系数在计算图像Hash时的权重，使得图像Hash更好地体现视觉特征，并提高鲁棒性。将原始图像的分块DCT系数乘以若干由密钥控制生成的伪随机矩阵，再对计算的结果进行基于分块的Watson人眼视觉特性处理，最后进行量化判决产生固定长度的图像Hash序列。本算法比未采用视觉特性的算法相比，提高了对JPEG压缩和高斯滤波的鲁棒性。图像摘要序列由密钥控制生成，具有安全性。
上传时间： 2016-01-19
上传用户：wendy15
I have a dream that I am always young. Then I will have enough energy to do everything whenever I want. Moreover, I don t have to worry about the old age during which I even can t take care of myself
标签： have everything whenever always
上传时间： 2016-01-24
上传用户：whenfly
由上述实验过程的图像变化可知，经过傅立叶变换和反变换及DCT离散余弦变换和反变换后，图像都发生了很大的变化，首先是经过2-D傅立叶变换后，图像数据频域出现高频数据集中，低频数据在四周的现象，然后再经过2-D傅立叶变换反变换后，图像再次恢复原始图。而2-D离散余弦变换对图像的影响也是如此。
上传时间： 2016-02-05
上传用户：pkkkkp
Jpeg2000编解码器，附VC、Delphi等常用编程语言的使用例程 J2K-Codec ver 1.9 === === === === === === === === ===== Make your graphics look better with an easy-to-use JPEG 2000 decoding component. J2K-Codec can help game developers, screensaver creators and many others to improve their products--to achieve better image quality and reduce installation package size. The new image compression standard based on wavelet technology has many interesting features not available in the old JPEG, such as alpha-channel and varied resolution levels.
上传时间： 2013-12-27
上传用户：kytqcool
=== === === === === === === === === === ==== IBM PC KEYBOARD INFORMATION FOR SOFTWARE DEVELOPERS ================================================================ Sources: PORTS.A of Ralf Brown s interrupt list collection repairfaq.org keyboard FAQ(doesn t appear to exsist) Linux source code Test hardware: New Samsung KB3T001SAXAA 104-key keyboard Old Maxi 2186035-00-21 101-key keyboard NO WARRANTY. NO GUARANTEE. I have tried to make this information accurate. I don t know if I succeeded. Corrections or additional information would be welcome. This is a plain-text document. If you use a word-processor to view it, use a fixed-pitch font (like Courier) so columnar data and ASCII art lines up properly.
标签： INFORMATION DEVELOPERS KEYBOARD SOFTWARE
上传时间： 2014-08-18
上传用户：ecooo
几种常用的压缩算法 本程序包含以下功能： 1、 Arithmetic coding 2、 Huffman coding 3、 LZ77 coding 4、 LZ78 coding 5、 LZW 6、 RLE 7、 DCT 8、 Furie transform
标签： coding Arithmetic Huffman LZ
上传时间： 2014-01-18
上传用户：caozhizhi
the attached utility is a work I ve submitted to the university It shows what a jpeg compression is all about. the function implements the DCT transform, using a matrix operator. note that matlab has a function for the DCT and iDCT transforms that might be more efficient.
标签： compression university the submitted
上传时间： 2014-01-15
上传用户：Altman
Back in 2002, the 6502 disappeared out of all catalogues. Wanted to know, if it s possible to build a binary compatible CPU with the things I had in the drawer: 74LS parts, 27C512 EPROMs and a fast static RAM from an old 80386 motherboard. Now here the results. Note, that the Bus timing is different from the 6502.
标签： disappeared catalogues possible Wanted
上传时间： 2016-04-09
上传用户：hn891122
--- --- --- --- --- --- Visual Studio Project Renamer For Win9x/NT/2k By Niek Albers nieka@daansystems.com (C)2001 DaanSystems Homepage: http://www.daansystems.com ------------------------------------ Use with care and on your own risk! Make backups before you use this program. Do a rebuild all on your renamed project. Usage: vsrename <oldname> <newname> <dir> Where: oldname : The old name of your project (typically the xxx from xxx.dsw) newname : The new name for your project dir : The directory tree that holds the project. The program will replace all occurences of oldname to newname in all files and rename all filenames that have the old name in it. It will walk subdirectories.
标签： Project Renamer Visual Studio
上传时间： 2013-12-15
上传用户：13517191407
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
