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 do I use mysql compress() / uncompress() with hibernate?

How do I use mysql's compress() and uncompress() functions to compress text before I store it and uncompress it when I retrieve it using a mysql database with hibernate for ORM?
ScArcher2
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Compressing digitalized document images

We are now required by law to digitalize all the financial documents in our company and submit them to evaluations every 3 months. Since this is sensitive data we decided to take matters into our own hands and build some sort of digital data…
Adabada
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Merge Order in Huffman Coding with same weight trees

I am really struggling with the order of merging trees that have the same "weight" in Huffman Coding. I looked into a lot of sources but all of them seem to cover just "simple cases" where there are no more than two elements with the same weight or…
Robert
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Get Maximum Compression from 7zip compression algorithm

I am trying to compress some of my large document files. But most of files are getting compresses by only 10% maximum. I am using 7zip Terminal Commands. 7z a filename.7z -m0=LZMA -mx=9 -mmt=on -aoa -mfb=64 filename.pptx Any suggestion on changing…
Shilpi Agrawal
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Are there any executable compressors that work with 64 bit binaries?

I'm looking for a tool like Bitsum Technologies' excellent PECompact tool for compressing Windows executables, but which works with 64 bit binaries. Does such a tool exist? Note: I don't care about the supposed obfuscation such a compressor…
Billy ONeal
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Using LZ4 with Apache Spark

I am trying to use LZ4 compression with Apache Spark and I understand that using the regular textFile method should be sufficient. However, if I load my file uncompressed everything works as expected but if I do it lz4-compressed the output ends up…
hveiga
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The gzuncompress of php equivalent on javascript

I have a php file that do: echo(gzcompress("TEST COMPRESS")); and on javascript i do a request on php and i want a function that do the same of gzuncompress(data) for take the result = "TEST COMPRESS" again on client side. EDIT: Thank you @aaronk6,…
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JAVA NIO ZIP FileSystem equivalent to ZipOutputStream setLevel

is there a ZipOutputStream setLevel(9) equivalent in JAVA NIOs ZIP FileSystem? Thanks in advance.
dforce
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Javascript proof-of-concept of GIF (re)compression

My program Precomp can be used to further compress already compressed file formats like GIF, PNG, PDF, ZIP and more. Roughly summarized, it does this by decompressing the compressed streams, recompressing them and storing the differences between the…
schnaader
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Android - Compressing bitmap very slow on one phone, quick on the other

I'm writing an app with a simple camera function. I take a picture in my main activity, and start a new thread which rotates the image, adds a transparent watermark and saves it as a .PNG. This app runs great on my samsung galaxy S3 running a custom…
AndroidAddict
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how to compress more jquery file?

is there any way to compress more jquery base file? what i have is about 56K and i need a more light file because of dial-up speed(56k).
hd.
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Applying gzip compression to files served by grunt-contrib-connect

It's pretty simple: I want to simulate the page-size of my website using grunt-contrib-connect before I deploy the site onto Apache. With Apache, it's pretty straight-forward to turn on gzip-compression. However, with grunt-contrib-connect, I…
uglow
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Fractal based Image compression algorithm (and source code)

I am looking for a decent fractal based compression algorithm for images. So far I only find dead links to the FIF image format and dead links pointing to Iterated Systems Inc which then became MediaBin which then became nothing from what I can see.
michael
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Express: Serve pre-compressed static assets

I'd like to pre-compress my static assets (excluding images) and serve them. To serve the public folder, I have: app.use(express.static('path/to/public/')); I believe express.compress() compresses on-the-fly, which seems like an unnecessary burden…
eye_mew
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Opengl best texture compression format on desktop nowadays

I did not find any valid resource online that is updated and compare the texture compression formats for OpenGL for desktop. Everything is either outdated or for mobile. Looking on my platform, I see many different…
elect
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