To do that:. Implementations are required to support the following codecs: "null" and "deflate". You can read a complete description of it in the Wikipedia article on the subject. Also this question in the FAQ shows that I should plan to enable it at a date/time when I have enough time to test all sites and adapt the configuration:. Examples of lossless algorithms for compression are Flate/deflate compression, Huffman compression, RLE compression and so on python compression. free C++ library for cryptography: includes ciphers, message authentication codes, one-way hash functions, public-key cryptosystems, key agreement schemes, and deflate compression. How to Enable JSON Gzip Compression in Apache How to Install and Use. The deflate algorithm, the compression approach used in the original Pkzip 2. Specify record names You can specify the record name and namespace to use by passing a map of parameters with recordName and recordNamespace. The ZLIB compression library was initially developed as part of the PNG graphics standard and is not protected by patents. Original question mentions memcached usage so my take on efficiency will be purely around resulting serialized object size for I/O latency and shared resource usage concerns. Linear scalability and proven fault-tolerance on commodity hardware or cloud infrastructure make it the perfect platform for mission-critical data. When you talk about HTTP web services, you're almost always talking about moving text-based data back and forth over the wire. This tool checks your server to see if you have Gzip compression enabled. Q&A c# – DeflateStream:読み込み中にファイルを圧縮する. method is the compression algorithm. This is a Wireshark capture of a Server Hello message (response to Client Hello). ### A simple python script to compress and decompress using lz77 compression algorithm. lighttpd-1. Or rather, it controls whether data should be compressed at all. Efficiency is a bit overloaded term. Welcome! If you don't have a Git account, you can't do anything here. That's because the server might not be able to deliver the compressed representation of the resource that I'm asking for. For certain formats, imwrite can accept additional name-value pair arguments. It's made for C (ISO C90), and has a C++ wrapper with a more convenient interface on top. Python; Ruby; C#、VB. This is a basic form of compression that is comparable to that used by standard Targa files. ") Example 2-43 shows how the … - Selection from Python Standard Library [Book]. I'm using Django if that makes it any easier. With this module you can compress, deflate / gzip large files (like concatenated *. * The better compression made a different of about 1 second to most users. Apparently, deflate is supposed to be "raw" LZ77. November 27, 2015. Use the methods described here to see how much data will actually be compressed before you compress and store data, or to see how much data was compressed after you have stored data. Previously, you learned how to use functions to make your program do something. The compression support covers the following aspects: Compression streams (Deflate & gzip) Reading and writing ZIP archives; We also released an update to our HttpClient NuGet package that takes a dependency on Microsoft. This compression algorithm isn't always available and has patent and license restrictions. LZMA / LZMA2 are default and general compression methods of 7z format in the 7-Zip program. Additional information about GZ file format. We can enable the GZIP compression from the cPanel itself, befroe doing that you need to enable the mod_deflate module on Apache. The target performance point for LZF is very high-speed compression with an "acceptable" compression ratio. 0 and later. Finally, the tool can generate graphs mapping the firmware image’s “entropy”, which is a graphical representation of real data in the image, as opposed to blank or unused space. Then when I'll receive my response I have to deflate the body of my response. SetOutputFilter DEFLATE. PNG compression method 0 (the only compression method presently defined for PNG) specifies deflate/inflate compression with a sliding window of at most 32768 bytes. This is a common observation that heavy sites generally run bit slowly than light weight sites that take less amount of space. Compressing and Decompressing File. This is because the longest run that can be encoded is 258 bytes. tif mydataset_jpeg. G-Loaded Journal is a technical blog that publishes news, guides and tutorials about GNU/Linux and other Free Open-Source Software. One of the tuning activities is to turn on GZIP compression for HTTP requests. , in ZIP compression) or arithmetic coding. The deflate is using Compression = 1 in the settings. The documentation is very good on how to do this but misses one point. This algorithm was quite groundbreaking - it was fast and still achieved moderately good compression. (C#) Deflate File. Custom date formats follow the formats at java. -dictionary binData This read-write options gets or sets the compression dictionary to use when working with compressing or decompressing the data to be. This will indicate to us that we can deliver compressed data to you which on your side should be decompressed transparently. LZO is a portable lossless data compression library written in ANSI C. By Ilya Grigorik on November 27, 2013. DEFLATE Compression Algorithm Corrects for Overestimation of Phylogenetic Diversity by Grantham Approach to Single-Nucleotide Polymorphism Classification International Journal of Molecular Sciences May 13, 2014. This is a basic form of compression that is comparable to that used by standard Targa files. Or rather, it controls whether data should be compressed at all. Supports large number of clients even on modest hardware due to being asynchronous. A file header is thus described by the following schema:. If someone steals these static resources of the website, it will obviously increase the bandwidth pressure of the server. IP address to Hostname conversion: Finds the hostname associated with any IP address. Layouts are accessed using the listLayouts method on the ArcGISProject object and it returns a Python list of Layout objects. Nothing to fear from decompression: it is as quick whatever the compression level. What is Gzip/Deflate compression and why do you need it? Compression is a simple and effective way to save bandwidth and speed up your website. cPanel/Plesk Server Management for just $59/mo with Unlimited tickets, Unlimited admin hours, Security audits, 24×7 monitoring and lot more. Configuring & Optimizing WebSocket Compression. POE provides a unified interface for several other event loops, including sel RCAPUTO /POE-1. The website speed depends upon many factors. If you use the GZipStream to compress a file (and save it with the extension. QuickLZ is the world's fastest compression library, reaching 308 Mbyte/s per core. no codec b. An early alpha preview version of the Brotli compression library is available for you today. That's because the server might not be able to deliver the compressed representation of the resource that I'm asking for. Base64 encode your data in a hassle-free way, or decode it into human-readable format. 6 MB/s at level 22 while covering compression ratios from 3. If not given, the default compression level will be the default compression level of the zlib library. Users of LZMA Utils should move to XZ Utils. Fastq Format Compression Software July 2017 – October. No official specification of the binary logging format is available. It may be compiled into an SQLite loadable extension using a command like:. -Z cm --compression-method cm Set the default compression method. It is a free transparent PNG image, you can download and redesign it for your creative projects. I recently had to redistribute internally the data from python nltk, and tried to compress/decompress with different tools, this was my result (picked lzip again):. Made available under the GNU LGPL license. With lzw and deflate compression using -co predictor=2 can help with imagery that is smoothly varying as it compresses the differences from pixel to pixel instead of the absolute values, and these will tend to be small and have more patterns. compression. Data Compression, also known as source coding, is the process of encoding or converting data in such a way that it consumes less memory space. The Apache Cassandra database is the right choice when you need scalability and high availability without compromising performance. Now continuing with the widespread use of Zstd throughout the Linux kernel and other areas, this Facebook-developed compression algorithm will work with Pstore. ZIP_DEFLATED, which gives you “deflate” compression. Even more surprising, virtually every implementation of those three actually use the same lossless data compression algorithm. How long and devotedly the algorithm searches for a string before it stops is defined by the compression level. 2-stage compression process: 1. sav game file. Zopfli usually creates shorter DEFLATE streams. Today we will see how to use gzip and gunzip commands with examples. With this module you can compress, deflate / gzip large files (like concatenated *. Heya! I've run into a small problem when making requests against your API. 2019-08-22 stream compression deflate c wcf. Deflate compression is used in e. The images are stored using the DEFLATE algorithm (same as PNG and ZIP and which is included in the standard Python distribution). Implement a software dedicated for all kinds of formats. These are the top rated real world C# (CSharp) examples of ICSharpCode. View HTTP Headers: View the HTTP headers sent by the web server when any file is requested. 367 - 03 Jun 2015 14:20:42 GMT - Search in distribution. The crc is given as ffffffff for a file not in gzip format. The MATLAB file format registry determines which file formats are supported. It was a lossless algorithm, and was patented in the USA under patent number 5051745. This is because the longest run that can be encoded is 258 bytes. We want 0 values to be nodata, deflate compression (more info here and here), predict is a parameter for the deflate compression. Python is an interpreted programming language, this means that as a developer you write Python (. How do I reference a Parameter from with a Python Script? Problem is. In Python you can use these options as well: dstImg = driver. This simple online text compression tool is compressing a plain text and decompressing compressed base64 string with gzip, bzip2 and deflate algorithms. Free C++ library for cryptographic schemes originally written by Wei Dai and includes ciphers, message authentication codes, one-way hash functions, public-key cryptosystems, key agreement schemes, and deflate compression. I don't support adding a new set_dictionary() method. How do I reference a Parameter from with a Python Script? Problem is. Even more surprising, virtually every implementation of those three actually use the same lossless data compression algorithm. About Your go-to C++ Toolbox. Exciting, New Cake Decorating Classes – Unleash the 1 last update 2019/10/31 Beast! I🔥I vpn for netlix vpn for windows | vpn for netlix > GET IT ★★★(VPNEasy)★★★ how to vpn for netlix for. INTRODUCTION Compression is a way of representing data in a way that requires fewer bits. This is our second post on compression and archiving series. c`: a standalone implementation capable of full decode. It was designed by Phil Katz, for version 2 of his PKZIP archiving tool. The LZF filter is a stand-alone compression filter for HDF5, which can be used in place of the built-in DEFLATE (or SZIP) compressors to provide faster compression. Deflated); //Add the FileEntry object to the ZIPFile object. Python; Ruby; C#、VB. eps format or any of the other export formats (not sure why). ) This code is capable of compressing any size file because the file data is compressed from input to output in a streaming mode. Data compression reduces the number of resources required to store and transmit data. SharpZipLib. 3 Jobs sind im Profil von David Clignez aufgelistet. The DeflateStream class uses the same compression algorithm as the gzip data format used by the GZipStream class. It seems that there are a few options: Find an existing implementation (ideal) of Inflate and Deflate in Python; Write my own Python extension to the zlib c library that includes Inflate and Deflate. # Version using encode vanishes in Python 3. For an example, see Writing Deflate Compressed Records. 1 The DEFLATE Compression Algorithm The 'deflate' compression format [Deutsch96], as used by the PKZIP and gzip compressors and as embodied in the freely and widely distributed zlib [Gailly95] library source code, has the following features: o an apparently unencumbered encoding and compression algorithm, with an open and publicly-available. Im trying to contact them to find out the answer. It is provided in Java and Python, and is open source. Sometimes setting the Content-Type header alone to text/csv will not accomplish what you want, usually downloading and opening the file in. The _____ codec from Google provides modest compression ratios. Q&A apache-2. Implement a software dedicated for all kinds of formats. Use Python zlib to recover Zip Files November 25, 2014. Lost update support Automatically adds back ETags into PUT requests to resources we have already cached. The JPEG Image Compression Standard is a very effective method for compressing digital images, but it does suffer from some problems. Deflate- It is the compression algorithm whose implementation is zlib. I support Al Klein's answer. compressobj(). Z_DEFAULT_COMPRESSION represents a default compromise between speed and compression (currently equivalent to level 6). There are several ways on how to decompress XZ archive on Linux. You have perhaps already found a a good method but make a few more tests with deflate and different predictor values. Simple integration to any platform, perfect conversion quality, fast and secure!. Compatible with Python 2. zipfile is a Python built-in module that provides tools to create, read, write, append, and list a ZIP file. Apache的deflate变种可能也没有zlib header,需要添加假头后处理。即MS的错误deflate (raw deflate). SetOutputFilter DEFLATE. To improve compression further, output from the LZ77 (LZSS) algorithm is usually passed through a Huffman coder (e. python Programming Guide. They are also known as LZ1 and LZ2 respectively. The Accept-Encoding header is used for negotiating content encoding. We will use -9 or --best options to specify. DEFLATE will be used for all other images. Deflate compression is used in e. For an example, see Writing Deflate Compressed Records. Each letter of the alphabet is coded as a sequence of dots and dashes. When the configuration is done, run make make install Then apache should have been installed. Layouts are accessed using the listLayouts method on the ArcGISProject object and it returns a Python list of Layout objects. TCL has "the event loop". Zlib ZlibCodec. Created using Python Zlib Decompress Example hi. Compression algorithm to use When the compress option is set and a python object is larger than compress_size_threshold. ADF Performance on Docker - Lighting Fast ADF performance depends on server processing power. Apache security chain Anti theft chain is to prevent others from stealing pictures, files, videos and other related resources of the server from the website code. Replacing gzip deflate with Nginx Brotli. You can disable mod_deflate per file like so (more here) SetEnvIfNoCase Request_URI get_file\. This tool supports Gzip compression from mod_deflate, mod_gzip or gzip compression through PHP and other server side programming languages. Gdal offers three lossless compression for geotiff: LZW, deflate and packbits. gzip_compression_level or passing gzip_compression_level=X to write() and savemat() where X is an integer between 0 and 9 inclusive. The server responds with the scheme used, indicated by the Content-Encoding response header. The data writer must specify a deflation level, from 1 to 9. The LZF filter is a stand-alone compression filter for HDF5, which can be used in place of the built-in DEFLATE (or SZIP) compressors to provide faster compression. PYNQ is an open-source project from Xilinx that makes it easy to design embedded systems with Xilinx Zynq All Programmab. Apache Arrow; ARROW-3514 [Python] zlib deflate exception when writing Parquet file. This is a trade off. Filename extension is. –Default format on most digital cameras –Compression reduces file. With this module you can compress, deflate / gzip large files (like concatenated *. Run-length encoding in Python. As this compression algorithm is much more effective than that used in GIF images, we obtain better quality (24 bit colors + alpha channel) while still producesing smaller files (a test showed ~75%). Saluté, j'ai un petit pb de compression j'aimerai activer la cmpression deflate sur mes pages via apache je tourne sous wamp avec apache 2. Demonstrates how to use the Deflate compression algorithm to compress a file. The website speed depends upon many factors. If your SOAP web service supports gzip or deflate compression, then you can enable corresponding decompression in C# web service client. This disclosure is directed to dictionary-based compression, which may be employed to achieve stateful header compression without maintaining a complete deflate state. org/rfc/rfc1950. We will use -9 or --best options to specify. These are the top rated real world C# (CSharp) examples of Ionic. If GZIP/Deflate compression is being used, the compression level can be adjusted by setting Options. ”) Example 2-43 shows how the … - Selection from Python Standard Library [Book]. This article demonstrates the using of binary formats in JavaScript code. It supports methods for reading data about existing archives as well as modifying the archives by adding. The supported compression types are uncompressed, snappy, and deflate. It was a lossless algorithm, and was patented in the USA under patent number 5051745. Level 9 is intended to compress smaller than level 1. On macOS, which is a full POSIX compliant UNIX (formally certified!), OpenSSL has no zlib support, there is no zlib-flate either and while the first solution works as well as all the Python solutions, the first solution requires the ZIP data to be in a file and all the other solutions force you to create a Python script. It therefor can be "decompressed" (which makes it 6 times smaller) with the standard gzip. ### A simple python script to compress and decompress using lz77 compression algorithm. the size and compression ratio of your content (how large the files are to start with and how small they become when compressed) 2. (The deflate compression algorithm is the most commonly used in the Zip archive file format. Sehen Sie sich auf LinkedIn das vollständige Profil an. Apache Sqoop Tutorial: Sqoop is a tool for transferring data between Hadoop & relational databases. Recently I discussed run-length encoding and DEFLATE compression. Deflate - org. And as we said before this operation drastically reduces transfer time since the files are much smaller. Enable this preference if gzip or deflate encoded (compressed) HTTP entities should be decoded. GZIP produces zipped files with the. The compression algorithm depends on what format is being produced or consumed. Secondly, we see that my DEFLATE library is 4. How do I obtain index. Zopfli usually creates shorter DEFLATE streams. a) Snapcheck b) Snappy c) FileCompress d) None of the mentioned View Answer. This category contains important information about using script and programming languages in your Web Hosting package. Well that's pretty easy too. The zipfile module. Deflate compression is an LZ77 derivative used in zip, gzip, pkzip, and related programs. You can read a complete description of it in the Wikipedia article on the subject. /configure --enable-deflate If you need enable other modules you can specify in the command. In 1977, they published a paper on "sliding-window" compression, and followed it with another paper in 1978 on "dictionary" based compression. The result is an unsigned 32-bit integer. A quick benchmark on ARM64 (odroid, Cortex A53), on kernel Image (12MB), use default compression level (-6) because no way to configure the compression level of btrfs. 9 gives the best compression, but is the slowest. Brotli is a new compression algorithm optimized for the web, in particular small text documents. This algorithm was quite groundbreaking – it was fast and still achieved moderately good compression. Peek-a-Boo Pattern Shop carries printable sewing patterns for children and adults. (You'll also hear this referred to as the "DEFLATE" filter; in the HDF5 world both names are used for the same filter. LZMA Utils are no longer developed, although critical bugs may be fixed as long as fixing them doesn't require huge changes to the code. zlib, gzip and mod_deflate on Apache HTTPD server compress your web pages and serve them to client's web browsers which can save and reduce bandwidth usage. LZMA is a compression algorithm allowing you to increase effort to compress, resulting in smaller results but with near-equal decompression time. 2009-06-01 • Python, Streams • Comments. This tool checks your server to see if you have Gzip compression enabled. * DEFLATE (DEFLATE is a lossless data compression algorithm and associated file format that uses a combination of the LZ77 algorithm and Huffman coding) * RLE (Run-length encoding is a very simple. php is included so unless there is a different requirement from your app to do compression at php level is not. gzip_compression_level or passing gzip_compression_level=X to write() and savemat() where X is an integer between 0 and 9 inclusive. There are ports and bindings in various languages like Java, C#, Python etc. On macOS, which is a full POSIX compliant UNIX (formally certified!), OpenSSL has no zlib support, there is no zlib-flate either and while the first solution works as well as all the Python solutions, the first solution requires the ZIP data to be in a file and all the other solutions force you to create a Python script. INTRODUCTION Compression is a way of representing data in a way that requires fewer bits. Ruby doesn't have libraries to support the compress (Lempel-Ziv) compression, so that is not supported. Now I know that there is a Deflate implementation available (Pyflate), but I do not know of an Inflate implementation. Z_DEFAULT_COMPRESSION represents a default compromise between speed and compression (currently equivalent to level 6). This is a basic form of compression that is comparable to that used by standard Targa files. Python Zlib Decompress Example. Linear scalability and proven fault-tolerance on commodity hardware or cloud infrastructure make it the perfect platform for mission-critical data. URL Encode Deflate Base64 Remove linebreaks URL Encode URL Decode Encode Decode (0 chars) Escape btoa atob Normalize XML. How to enable GZip compression for Files to save site’s bandwidth. zlib is a software library used for data compression. This shows that gzip (and deflate and any compression tool that uses one of them) but also, as I expect, any other compression format can be used to augment data significantly. NET Framework 2. You can rate examples to help us improve the quality of examples. Apache httpd 2. This script simply INSERT the requested table/partition to a new table, let data be merged by Hive itself, then INSERT back with compression. The deflate compressor is given a great deal of flexibility as to how to compress the data. Also, the PREDICTOR=2 setting gives better compression for natural images with lots of tones but in your images the neighrouring pixels may not have correlation and then PREDICTOR=1 should lead to better compression. Since then support has been introduced for other compression methods, including the one which we were asked to investigate as to its effectiveness – namely Deflate, more commonly referred to as Zip compression. RasterXSize, srcImg. zip is used to compress the input data and fill the given buffer with the compressed data. Gzip compression helps the webserver to provide the smaller file size and hence the website loads more faster. Well organized and easy to understand Web building tutorials with lots of examples of how to use HTML, CSS, JavaScript, SQL, PHP, Python, Bootstrap, Java and XML. They are extracted from open source Python projects. Custom date formats follow the formats at java. It was originally defined by Phil Katz for version 2 of his PKZIP… 📐 📓 📒 📝. It’s just a quick win to enable your web forms or MVC application to utilise Gzip / Deflate compression and thus speed up the users experience of your web-site. WinZip ® provides several methods for compressing the files that you add to a Zip file. Run-length encoding in Python. Additional information about GZ file format. This can be one of the known case-insensitive shorten names (none, bzip2, gzip, lz4, snappy and deflate). Can be given as 0 for no compression up to 9 for maximum compression. Content-Encoding: gzip. Image transformation, compression, and decompression codecs. Furthermore, mod_deflate has a few of its own important configuration options: DeflateCompressionLevel — The compression level to be applied. Please read the FAQ and the manual before asking us for help. The is_zipfile() function returns a boolean indicating whether or not the filename passed as an argument refers to a valid ZIP file. The major drawback. uzlib - Radically unbloated DEFLATE zlib gzip compression decompression library #opensource. Compression is restricted to DEFLATE; digital signatures are not supported. 367 - 03 Jun 2015 14:20:42 GMT - Search in distribution. tif # Create a COGEO with JPEG profile and the first 3 bands of the data and add internal mask $ rio cogeo create mydataset. DEFLATE with a gzip wrapper) libdeflate is heavily optimized. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required. Q&A apache-2. DEFLATE: run-length encoding, but better. So if a browser supports compression, its HTTP request will include a header similar to one of the following. Lisant pas mal de chose sur la perf je vois pas mal de blog recommander l'activation des compression zopfli/brotli cependant je me pose deux questions Sur des benchmark je lis que le Zopfli n'apporterais que 3/5% des perf par rapport à deflate. Quick benchmark on ARM64. Features: C# source code 100% managed, without unsafe blocks Free for use in commercial software with closed source code BSD style license. The format has widespread use, and can be found in protocols and file formats such as ZIP, gzip, PNG, HTTP, and Git. The JPEG Image Compression Standard is a very effective method for compressing digital images, but it does suffer from some problems. Miller,andJeffreyA. Click to save the current settings. The patent application clai med that if it was applied recursively,. The zlib Module (Optional) The zlib module provides support for “zlib” compression. An Example An LZ77 decoding example of the triple <7, 4, C(r)> is shown below: All popular archivers (arj, lha, zip, zoo) are variations on the LZ77 theme. How do I obtain index. Compression NuGet package is supported on the following. This provides a very simple class that represents an R,G,B canvas. The BREACH attack can be exploited with just a few thousand requests, and can be executed in under a minute. Introduction to Data Compression, Third Edition KhalidSayood Understanding Digital Libraries, Second Edition MichaelLesk Bioinformatics: Managing Scientific Data ZoeLacroixandTerenceCritchlow How to Build a Digital Library IanH. It is fully described in the specifications at the java. A Quick Benchmark: Gzip vs. Default is 6. It therefor can be "decompressed" (which makes it 6 times smaller) with the standard gzip. Just like with GZip, DEFLATE compresses a single file and does not hold multiple files in a zip archive fashion. IP address to Hostname conversion: Finds the hostname associated with any IP address. 0x78 is a lowercase letter x, so easy to recognize in an ASCII dump. PNG Canvas in Python. An early alpha preview version of the Brotli compression library is available for you today. A return value of 0 indicates that needsInput should be called in order to determine if more input data is required. c file of the main SQLite source tree. Python comes with library called zlib that is designed to handle the compression and decompression of data. Fastq Format Compression Software July 2017 – October. Currently the main methods supported by zip are store and deflate. The company was the first archiver to use the LZMA algorithm, which uses an internal dictionary to encode data bit by bit. You can vote up the examples you like or vote down the ones you don't like. We have collection of more than 1 Million open source products ranging from Enterprise product to small libraries in all platforms. TCL has "the event loop". If you receive a GZIP file, you can save it to your desktop and open it with WinZip. # Create a COGEO with DEFLATE compression (Using default `Deflate` profile) $ rio cogeo create mydataset. Gzip compression seems to work on html not other files apache gzip compression does not work on all files. The GZIP compression technique in cPanel compress the image file and increase the file transferring speed. The result is an unsigned 32-bit integer. If you compress with a DeflateStream, those tools won't recognize the file. Save Defaults. The compression in VS2005 has two flavors; one based on GZip and the other on the Deflate algorithm. Intended audience This specification is intended for use by implementors of software to compress data into zlib format and/or decompress data from zlib format. Python has Twisted. The following code fragment demonstrates a trivial compression and decompression of a string using Deflater and Inflater. In 1977, they published a paper on "sliding-window" compression, and followed it with another paper in 1978 on "dictionary" based compression. PerMessageDeflateOffer`. Si te dedicas a lo que te entusiasma y haces las cosas con pasión, no habrá nada que se te resista. Free online text compression tools - gzip, bzip2 and deflate. Python; Ruby; C#、VB. Deflate Algorithm Codes and Scripts Downloads Free. It is clear that zlib. Larger files and slower networks (and internet connections) will benefit the most from compression. The target performance point for LZF is very high-speed compression with an "acceptable" compression ratio. On macOS, which is a full POSIX compliant UNIX (formally certified!), OpenSSL has no zlib support, there is no zlib-flate either and while the first solution works as well as all the Python solutions, the first solution requires the ZIP data to be in a file and all the other solutions force you to create a Python script. I have modified my implementation of RFC 1951 "Deflate" compression to use two threads. Image transformation, compression, and decompression codecs. Run-length encoding is a simple compression scheme in which runs of equal values are represented by the value and a repeat count. The only compression algorithm allowed is DEFLATE (RFC 1951). The code can be used for study, and as a solid basis for modification and extension. /configure --enable-deflate If you need enable other modules you can specify in the command. 0 some further setup may be required by Apache in order for mod_deflate to operate properly. Image compression - Huffman coding. How long and devotedly the algorithm searches for a string before it stops is defined by the compression level. Hostname to IP address conversion: Finds the IP addresses associated with any hostname. (This compression method is also known as “deflate. We discuss DEFLATE in a later chapter of this book, Data Compression/Multiple transformations#DEFLATE. To enable GZIP compression you only need to enable "Apache Module mod_deflate" you can search how to enable it on your distro.