compression

问题 EDIT: Specifically compression and extraction speeds. Any Suggestions? Thanks 回答1: So I made a random-ish large zipfile: $ ls -l *zip -rw-r--r-- 1 aleax 5000 115749854 Nov 18 19:16 large.zip $ unzip -l large.zip | wc 23396 93633 2254735 i.e., 116 MB with 23.4K files in it, and timed things: $ time unzip -d /tmp large.zip >/dev/null real 0m14.702s user 0m2.586s sys 0m5.408s this is the system-supplied commandline unzip binary -- no doubt as finely-tuned and optimized as a pure C executable can

问题 EDIT: Specifically compression and extraction speeds. Any Suggestions? Thanks 回答1: So I made a random-ish large zipfile: $ ls -l *zip -rw-r--r-- 1 aleax 5000 115749854 Nov 18 19:16 large.zip $ unzip -l large.zip | wc 23396 93633 2254735 i.e., 116 MB with 23.4K files in it, and timed things: $ time unzip -d /tmp large.zip >/dev/null real 0m14.702s user 0m2.586s sys 0m5.408s this is the system-supplied commandline unzip binary -- no doubt as finely-tuned and optimized as a pure C executable can

问题 I sometimes need to post larger JSON request payloads to my ASP.Net Core Controllers. The size of the payload warrants (at least in my opinion) compressing it. Because ASP.Net Core Controllers do not appear to support compressed request content out of the box, I've rolled my own middleware. Implementing this was so trivial that I'm not sure if I'm missing something here. Either because there's a built-in way to achieve this or because I made some major mistake from a security- or performance

问题 I'm trying to understand the effect of the Block Size and best strategy of choosing the Coefficients in DCT compression. Basically I want to ask what I wrote here: Video Compression: What is discrete cosine transform? Lets assume the most primitive compression. Making block of an image. Performing a DCT on each blog and zeroing out some coefficients. To my understanding, the smaller the block the better. Smaller blocks means the Pixels are more correlated hence the energy in the DCT spectrum

问题 I have been trying to compress and store a json encoded string into mysql, but I am getting "unexpected /" errors. I also tried to use addslashes like this: addslashes(gzcompress(json_encode($mystring))); And to display json_decode(gzuncompress(stripslashes($mystring))); But it fails on insert with the error I mentioned. I read somewhere a string with gzcompress should be stored as a blob, but I was hoping there is a way to store it in a mysql text field so I dont have to mess with the db. PS

问题 I am trying to write a batch script that will run automatically compressing subdirectories using winrar or 7-zip: Example: My Pictures Pics1 (Pics1.zip) File1.jpg File2.jpg File3.jpg Pics2 (Pics2.zip) File4.jpg File5.jpg Pics3 (Pics3.zip) File6.jpg File7.jpg ... How do i write script. 回答1: (1) Using WinRAR: WinRAR includes two command-line tools, rar.exe and unrar.exe , where rar.exe compresses and unrar.exe uncompresses files. Both are located in the C:\Program Files\WinRAR folder in the

问题 I have an iPhone application that I have developed using ARC. I have a folder that contains a heap of images in my documents directory that I need to zip up and e-mail. My project uses ARC. Does anyone have any example code/links to a resource that would be helpful to me? I've been raking around online and what I can find is not compatible with ARC - even when it claims to be. 回答1: Download and drag the Objective-Zip, MiniZip and ZLib drag in to your project from this link http://code.google

问题 I have a .html document with CSS and Javascript inside of document (no external files). Is there some online tool that would minify document and Javascript to some very small footprint? I saw many scripts kind of unreadable, where all variables and function names are replaced with one-letter names, etc. Please advice. 回答1: Edit 2 (Feb 22, 2017): Now the best tool to minify your assets (and a whole lot more, by adding loaders and plugins) is definitely Webpack. Example of config to move all

问题 I have a simple code to extract zip files, it was working just fine as expected but during my test I tried my code with some zip files (fonts, icons and templates I downloaded from internet) just to make sure it should extract any zip files provided, but its not working with some zip files, here is the minimized code to regenerate this issue: package com.test.mytest; import java.io.FileInputStream; import java.util.Enumeration; import java.util.zip.ZipEntry; import java.util.zip.ZipFile;

问题 Is it possible to do random access (a lot of seeks) to very huge file, compressed by 7zip? The original file is very huge (999gb xml) and I can't store it in unpacked format (i have no so much free space). So, if 7z format allows accessing to middle block without uncompressing all blocks before selected one, I can built an index of block beginning and corresponding original file offsets. Header of my 7z archive is 37 7A BC AF 27 1C 00 02 28 99 F1 9D 4A 46 D7 EA // 7z archive version 2;crc; n