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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Delphi XE and ZLib Problems

I'm in Delphi XE and I'm having some problems with ZLib routines... I'm trying to compress some strings (and encode it to send it via a SOAP webservice -not really important-) The string results from ZDecompressString differs used in…
JosepMaria
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Google Sitemaps "Compression error" in Webmaster Tools

We're creating Sitemap XML-files and pointing to them in Google Webmaster Tools, which sporadically gives the following error-message to some of the files: Compression error The "How to fix" in Google's documentation doesn't really give any hints…
Seb Nilsson
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PDF compressing library/tool

I am working on a project to reduce the size of the PDF's, compress them. I am wondering are there any good tools/library (.NET) in market that are really good. I did try few tools like Onstream Compression, but the results were not satisfactory.
Sabby62
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Google PageSpeed is requesting that I enable compression for files that are hosted by Google

When running the Page Speed test on pages with a Google map embedded I get this: Should Fix: Enable compression Compressing resources with gzip or deflate can reduce the number of bytes sent over the network. Enable compression for the…
user2094477
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Turn directory into Zip with PHP

How would I turn a directory into a zip file with PHP? Thanks.
usertest
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Lossless Compression for Coordinate Path Data

I am brainstorming for a project which will store large chunks of coordinate data (latitude, longitude) in a database. Key aspects of this data will be calculated and stored, and then the bulk of the data will be compressed and stored. I am looking…
Nate
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compress and decompress String using DeflaterOutputStream and InflaterInputStream in java

I need to save a string on a file and I am using DeflaterOutputStream to compress. when I try to decompress I can't get the original String. I get an uncleared symbols. Her is my code: public static void decompress() throws Exception { …
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DotNetZip unable to zip a huge number of entries

I'm using dotnet zip in the following way: using (ZipFile zip = new ZipFile(@"E:\test2.zip")) { zip.ParallelDeflateThreshold = -1; zip.UseZip64WhenSaving = Zip64Option.Always; zip.SaveProgress += SaveProgress; …
user2878881
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What's the best audio compression library for .NET?

I'm looking for a good audio compression library for .NET. Anything using MP3 is out (because of the licensing issue). Basically I just need to be able to compress regular WAV audio data into some format, and decompress back to WAV. Preferably…
MusiGenesis
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Can anyone make heads or tales of this spigot algorithm code Pitiny.c

This C program is just 143 characters long! But it “decompresses” into the first 10,000 digits of Pi. // Created by cheeseMan on 30/11/13. long a[35014],b,c=35014,d,e,f=1e4,g,h; int main(int argc, const char * argv[]) { for(;(b=c-=14); …
BrianBeaven
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why can't python execute a zip archive passed via stdin?

I have a zip archive containing a __main__.py file : archive.zip I can execute it with python archive.zip => OK ! but not with cat archive.zip | python => File "", line 1 SyntaxError: Non-ASCII character '\x9e' in file on line 2, but…
Jerome WAGNER
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ASP.NET compression

From an earlier post about trying to improve my sites performance I have been looking at HTTP compression. I have read about setting it up in IIS but it seems to be a global thing for all IIS application pools I may not be allowed to do this as…
PeteT
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How to Compress a String using Recursion? (RLE algorithm)

I'm having slight trouble trying to compress a string using recursion. For example, consider the following string: qwwwwwwwwweeeeerrtyyyyyqqqqwEErTTT After applying the RLE algorithm, this string is converted into: q9w5e2rt5y4qw2Er3T In the…
AChoi
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Difference between coding and compression?

I know compression is the process of re-encoding digital data to reduce file size; a specialized program called a codec, for COmpressor/DECompressor, changes the original file to the smaller version and then decompresses it to again present the…
user2922938
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Powershell system.io.compression zipping files and/or Folders

Im producing some automated tasks at work where i need to zip certain files and/or folders. What im trying to do is getting zip the text files in folder 1 which contains 4 txt files. Executing this command gives an error but still zips the txt…
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