Questions tagged [compression]

The name given to the process of encoding data such that it uses lesser number of bits as compared to the original representation.

There are a number of techniques to compress information, with most algorithms working to compress image, speech, music or video. Encoding the same information in lesser bits results in saving some crucial resource such as transmission bandwidth or hard-disk space. Compression algorithms also take advantage of human perception to further reduce the size of information. By encoding the same piece of information with fewer bits in places that the human brain is not accustomed to perceiving as well as other parts, substantial gains in compression ratios can be achieved.

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How to use the 7z SDK to compress and decompress a file

According to this link How do I create 7-Zip archives with .NET? , WOPR tell us how to compress a file with LMZA (7z compression algorithm) using 7z SDK ( http://www.7-zip.org/sdk.html ) using SevenZip.Compression.LZMA; private static void…
Djax
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Is there a built-in zip library in .NET 3.5?

Is there a built-in zip library in .NET 3.5? If not, what are the popular open source .net zip libraries.
Guy
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Notice: ob_end_flush(): failed to send buffer of zlib output compression (1) in

I don't have any problem on localhost. but when i tested my codes on server, end of every page i see this notice. my code:
AliN11
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What is the difference between httpCompression and urlCompression?

Looking at the node in a Web.config, I see that it allows both httpCompression and urlCompression elements. What's the difference between the two? I just want to do standard gzip, which one should I use?
Mike Comstock
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How do I output compressed CSS from Compass?

How do I configure compass to output smaller or compressed CSS files? I tried compass -s compressed but that didn't work.
Mark Robinson
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Tomcat 7 GZIP compression not working

I have added the following lines in tomcat's conf/server.xml file to enable gzip compression but its not working. Pages are still uncompressesd.
Popeye
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Removing extra whitespace from generated HTML in MVC

I have an MVC application view that is generating quite a large HTML table of values (>20MB). I am compressing the view in the controller using a compression filter internal class CompressFilter : ActionFilterAttribute { public override void…
WOPR
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why does IIS7 static/dynamic compression only work for 200 responses?

Why is IIS7.5 only performing static and dynamic compression when the response code is 200? How do I make it compress all responses where the request had an appropriate Accept-Encoding header? Thanks
Andrew Bullock
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Export to CSV and Compress with GZIP in postgres

I need to export a big table to csv file and compress it. I can export it using COPY command from postgres like - COPY foo_table to '/tmp/foo_table.csv' delimiters',' CSV HEADER; And then can compress it using gzip like - gzip -c…
Sujit
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Nothing happens when I try to send files / folders to Compressed (zipped) folder

For a while now, I've been unable to send files or folders to Zipped folder from windows explorer. The option is there, but when I click on it, nothing happens. It seems others have had similar problems, but in their cases, the option has been…
AutoBaker
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How to reduce the size of my iPhone application?

Alternative Titles (to aid searches) Compressing PNGs Reduce the size of an iPhone Archive (.ipa) Adding a build rule to compress images in Xcode iOS Apps can only be downloaded via 3G if they are less than 100MB. What are the best strategies for…
Sudharsanan
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What is the best compression algorithm that allows random reads/writes in a file?

What is the best compression algorithm that allows random reads/writes in a file? I know that any adaptive compression algorithms would be out of the question. And I know huffman encoding would be out of the question. Does anyone have a better…
Brian R. Bondy
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Compression API on the iPhone

Is there a compression API available for use on the iPhone? We're building some RESTful web services for our iPhone app to talk to, but we want to compress at least some of the conversations for efficiency. I don't care what the format (ZIP, LHA,…
Gregory Higley
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Is it possible to get the compressed and uncompressed sizes of a file on a btrfs file system?

Is it possible to determine what the compressed size (I assume that is what is listed by ls -l) and uncompressed size of files on a btrfs filesystem with transparent compression enabled?
gandalf3
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Installed .Net 4.5 but can't use ZipFile class in Visual C#

I'm kind of a newbie to Visual Studio programming. I recently upgraded .Net 4.0 to 4.5 in order to use the ZipFile class under System.IO.Compression, but after the installation completed, Visual Studio (I'm using 2012) still cannot recognize…
wuxilixi
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