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  • A compression program that handles files with unusual extensions

    - by ripper234
    WAR files are simply ZIP files with a renamed extension. I'd like to configure a compression program to handle these (on double-clicking the file), but jZip doesn't recognize them unless I rename them to .ZIP. I have setup Windows file associations, but jZip just wants to 'add them to archive' instead of opening them. Which compression program would you recommend?

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  • IIS 6 Compression for a folder

    - by Brian
    Hello, I want to enable IIS 6 compression for all of the folders in my application except one; in this one folder, I do some things that fails when IIS 6 compression is enabled... Any advice? Thanks.

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  • PNG Compression

    - by T Pops
    At work, on certain projects I have to manage a lot of images. Most of the time PNG files work the best for what I'm doing. With such a huge amount of images, I've tried using PNG compression with PNG Gauntlet but sometimes the file doesn't really change and sometimes PNG Gauntlet reports it would've made the filesize bigger! Am I just maxing out the compression or is there something more I can do?

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  • InnoDB Compression Improvements in MySQL 5.6

    - by Inaam Rana
    MySQL 5.6 comes with significant improvements for the compression support inside InnoDB. The enhancements that we'll talk about in this piece are also a good example of community contributions. The work on these was conceived, implemented and contributed by the engineers at Facebook. Before we plunge into the details let us familiarize ourselves with some of the key concepts surrounding InnoDB compression. In InnoDB compressed pages are fixed size. Supported sizes are 1, 2, 4, 8 and 16K. The compressed page size is specified at table creation time. InnoDB uses zlib for compression. InnoDB buffer pool will attempt to cache compressed pages like normal pages. However, whenever a page is actively used by a transaction, we'll always have the uncompressed version of the page as well i.e.: we can have a page in the buffer pool in compressed only form or in a state where we have both the compressed page and uncompressed version but we'll never have a page in uncompressed only form. On-disk we'll always only have the compressed page. When both compressed and uncompressed images are present in the buffer pool they are always kept in sync i.e.: changes are applied to both atomically. Recompression happens when changes are made to the compressed data. In order to minimize recompressions InnoDB maintains a modification log within a compressed page. This is the extra space available in the page after compression and it is used to log modifications to the compressed data thus avoiding recompressions. DELETE (and ROLLBACK of DELETE) and purge can be performed without recompressing the page. This is because the delete-mark bit and the system fields DB_TRX_ID and DB_ROLL_PTR are stored in uncompressed format on the compressed page. A record can be purged by shuffling entries in the compressed page directory. This can also be useful for updates of indexed columns, because UPDATE of a key is mapped to INSERT+DELETE+purge. A compression failure happens when we attempt to recompress a page and it does not fit in the fixed size. In such case, we first try to reorganize the page and attempt to recompress and if that fails as well then we split the page into two and recompress both pages. Now lets talk about the three major improvements that we made in MySQL 5.6.Logging of Compressed Page Images:InnoDB used to log entire compressed data on the page to the redo logs when recompression happens. This was an extra safety measure to guard against the rare case where an attempt is made to do recovery using a different zlib version from the one that was used before the crash. Because recovery is a page level operation in InnoDB we have to be sure that all recompress attempts must succeed without causing a btree page split. However, writing entire compressed data images to the redo log files not only makes the operation heavy duty but can also adversely affect flushing activity. This happens because redo space is used in a circular fashion and when we generate much more than normal redo we fill up the space much more quickly and in order to reuse the redo space we have to flush the corresponding dirty pages from the buffer pool.Starting with MySQL 5.6 a new global configuration parameter innodb_log_compressed_pages. The default value is true which is same as the current behavior. If you are sure that you are not going to attempt to recover from a crash using a different version of zlib then you should set this parameter to false. This is a dynamic parameter.Compression Level:You can now set the compression level that zlib should choose to compress the data. The global parameter is innodb_compression_level - the default value is 6 (the zlib default) and allowed values are 1 to 9. Again the parameter is dynamic i.e.: you can change it on the fly.Dynamic Padding to Reduce Compression Failures:Compression failures are expensive in terms of CPU. We go through the hoops of recompress, failure, reorganize, recompress, failure and finally page split. At the same time, how often we encounter compression failure depends largely on the compressibility of the data. In MySQL 5.6, courtesy of Facebook engineers, we have an adaptive algorithm based on per-index statistics that we gather about compression operations. The idea is that if a certain index/table is experiencing too many compression failures then we should try to pack the 16K uncompressed version of the page less densely i.e.: we let some space in the 16K page go unused in an attempt that the recompression won't end up in a failure. In other words, we dynamically keep adding 'pad' to the 16K page till we get compression failures within an agreeable range. It works the other way as well, that is we'll keep removing the pad if failure rate is fairly low. To tune the padding effort two configuration variables are exposed. innodb_compression_failure_threshold_pct: default 5, range 0 - 100,dynamic, implies the percentage of compress ops to fail before we start using to padding. Value 0 has a special meaning of disabling the padding. innodb_compression_pad_pct_max: default 50, range 0 - 75, dynamic, the  maximum percentage of uncompressed data page that can be reserved as pad.

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  • Internet compression proxy for low speed broadband?

    - by user23150
    I live in a rural location, using high-latency wireless off a local ISP's tower. My speed tests vary day to day, but I can get around 1Mb up/down. The problem is, I work with large files, uploading and downloading (HD videos, development software, etc.). It can be painful to wait sometimes. Plus I do some side contract game development, and it can be very difficult to playtest with other developers (200ms ping is a good day for me). Now, obviously it's not going to be easy to solve the latency problem without different wireless hardware. But speedwise, I am wondering if I can use some kind of compression technology on a proxy. For instance, my work computer has full access to a 26Mb down, 10Mb up connection, that is totally unused at night and the weekends. If I could run some kind of compression technology on our server, and use it as a proxy to route to my home computer, I could stand to gain some major speed. I realize that by bogging down a system with compression, I could potentially lose whatever speed gain I had. But the proxy server is a quad core xeon, and the receiving computer is a pretty decent i7 computer, so that shouldn't be a concern. I found http://toonel.net/ but it seems more geared toward very slow narrowband users, like dial-up. Plus, I would prefer to just be able to point my browser to a proxy server, rather then install software on my client machine. EDIT I thought about my question a little more, and realize I am going to need to install software on my client in order to decompress, and possible compress (for uploading). That's not a huge deal.

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  • JSON webservice response compression in IIS 7

    - by denisioru
    Hello! I have trouble with JSON response compression. I look to response headers after uploading website to production server (Windows 2008, IIS 7) and found uncompressed response. Turning on "Enabled static compression" and ""Enable dynamic compression" in IIS control panel does not effect. ASPX pages was responsed gzipped, but webservice response uncompressed. I looked to google, but no answer found about this trouble. Also, I try this http://stackoverflow.com/questions/2405595/json-ihttpmodule-compression way (and adding to web.config this module) - but this source is excellent working at development machine with ASP.NET development server (and have seven times response size reduced) and totally ignored at IIS7. How I can apply gzip compression to json responses from my webservice? Thanks. PS .NET 3.5

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  • How does NTFS compression affect performance?

    - by DragonLord
    I've heard that NTFS compression can reduce performance due to extra CPU usage, but I've read reports that it may actually increase performance because of reduced disk reads. How exactly does NTFS compression affect system performance? Notes: I'm running a laptop with a 5400 RPM hard drive, and many of the things I do on it are I/O bound. The processor is a AMD Phenom II with four cores running at 2.0 GHz. The system is defragmented regularly using UltraDefrag. The workload is mixed read-write, with reads occurring somewhat more often than writes. The files to be compressed include personal documents and selected programs, including several (less demanding) games and Visual Studio (which tends to be I/O bound more often than not).

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  • Windows software to copy from/to image/disk/partition with offset&compression

    - by Alex131089
    I tried to put everything in the title : I'm looking for a software that is able : to work with image (raw file), partition & whole disk, without distinction to copy whole image or only selected part (let's say .. from 0 to end of last partition, excluding free space for example ; or with start + offset/end system) to handle compression (at least gzip) You recognized, I'm looking for a "dd | gzip" utility with GUI on Windows. The closest tool I found so far is http://www.dubaron.com/diskimage/ but it's a bit old and don't have compression support. Any idea ?

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  • Determine compression ratio for Windows compressed drive

    - by munrobasher
    Is there a Windows 7 native way to display the overall compression ratio on a Windows compressed drive? As part of our disaster recovery process, we're copying some key system folders onto 2TB external hard drive, encrypted using TrueCrypt and copied using robocopy. The drive is compressed and I'd like to see what kind of compression ratio we're getting and whether it's actually worth the performance overhead. I know that TreeSize can possibly do this (as mentioned in another post) but want a OS native way if possible. Thanks, Rob.

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  • How does file compression work?

    - by Phoshi
    So, I realised today I take file compression for granted. The ability to bundle a few files together into one, and have it come out smaller than any of them, is something I just accept as a fact, but how does it actually work? I have a limited knowledge of it that includes something to do with replacing all the duplicate entries with pointers, to shrink that way, but beyond that I'm fairly clueless! As I'm always open to new knowledge, as I imagine most of us here are, I thought I'd ask. So, SuperUser, how does compression actually work?

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  • Domino Document data compression and design compression

    - by pipalia
    I was thinking of turning this on some large databases not just mail files - we have around 8 - 10GB of large databases as well as small databases of couple of hundred MB in size. But after reading this post I am not too sure: http://www-10.lotus.com/ldd/nd85forum.nsf/4b9931b774db788c85256bf0006b5e6d/1f4e67b569720e54852576c0003cb8ac?OpenDocument Can anyone confirm whether this is true? Are these any ill effects on performance by turning this feature on and if so what's the difference in performance? Thanks.

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  • how to enable iis 7 dynamic content compression?

    - by davidcl
    I've turned on dynamic content compression in IIS 7, but Fiddler is showing that my dynamic pages are still being served without content-encoding: gzip. Static content compression is working fine on the same servers. Not sure if it matters but most of the dynamic pages are coldfusion pages and we're also using the IIS URL rewriting module. This is from my applicationhost.config. <httpCompression directory="%SystemDrive%\inetpub\temp\IIS Temporary Compressed Files"> <scheme name="gzip" dll="%Windir%\system32\inetsrv\gzip.dll" /> <dynamicTypes> <add mimeType="text/*" enabled="true" /> <add mimeType="message/*" enabled="true" /> <add mimeType="application/javascript" enabled="true" /> <add mimeType="*/*" enabled="false" /> </dynamicTypes> <staticTypes> <add mimeType="text/*" enabled="true" /> <add mimeType="message/*" enabled="true" /> <add mimeType="application/javascript" enabled="true" /> <add mimeType="*/*" enabled="false" /> </staticTypes> </httpCompression> ... <urlCompression doDynamicCompression="true" /> Here's a sample request: GET / HTTP/1.1 Host: web5.example.com User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.2) Gecko/20100115 Firefox/3.6 (.NET CLR 3.5.30729) Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8 Accept-Language: en-us,en;q=0.5 Accept-Encoding: gzip,deflate Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7 Keep-Alive: 115 Connection: keep-alive and response header: HTTP/1.1 200 OK Transfer-Encoding: chunked Content-Type: text/html; charset=UTF-8 Server: Microsoft-IIS/7.0 ... Date: Mon, 22 Feb 2010 20:59:36 GMT

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  • Compression without Mod_Deflate

    - by pws5068
    Greetings all, After running tests with Google PageSpeed, I believe my site could really benefit from compressing js/html/css/php files. Unfortunately, my host (Host Gator) does not support Mod_Gzip or Mod_Deflate. I was able to enable php compression through the ini file. Is there another way to serve compressed files to browsers that support them, in a manner similar to Mod_Deflate?

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  • Apache/2.2.20 (Ubuntu 11.10) gzip compression won't work on php pages, content is chunked

    - by FamousInteractive
    I'm running into a problem with a new production server whereto I'm transferring projects. The HTML output of the PHP applications isn't compressed by the Apache mod_deflate module. Other resources, as stylesheet and javascript files, even html pages, which are served with the same Content-type (text/html) as the PHP output, are compressed! The projects use the following rules (from HTML5 boilerplate) in the .htaccess: <IfModule mod_deflate.c> # Force deflate for mangled headers developer.yahoo.com/blogs/ydn/posts/2010/12/pushing-beyond-gzipping/ <IfModule mod_setenvif.c> <IfModule mod_headers.c> SetEnvIfNoCase ^(Accept-EncodXng|X-cept-Encoding|X{15}|~{15}|-{15})$ ^((gzip|deflate)\s*,?\s*)+|[X~-]{4,13}$ HAVE_Accept-Encoding RequestHeader append Accept-Encoding "gzip,deflate" env=HAVE_Accept-Encoding </IfModule> </IfModule> # HTML, TXT, CSS, JavaScript, JSON, XML, HTC: <IfModule filter_module> FilterDeclare COMPRESS FilterProvider COMPRESS DEFLATE resp=Content-Type $text/html FilterProvider COMPRESS DEFLATE resp=Content-Type $text/css FilterProvider COMPRESS DEFLATE resp=Content-Type $text/plain FilterProvider COMPRESS DEFLATE resp=Content-Type $text/xml FilterProvider COMPRESS DEFLATE resp=Content-Type $text/x-component FilterProvider COMPRESS DEFLATE resp=Content-Type $application/javascript FilterProvider COMPRESS DEFLATE resp=Content-Type $application/json FilterProvider COMPRESS DEFLATE resp=Content-Type $application/xml FilterProvider COMPRESS DEFLATE resp=Content-Type $application/xhtml+xml FilterProvider COMPRESS DEFLATE resp=Content-Type $application/rss+xml FilterProvider COMPRESS DEFLATE resp=Content-Type $application/atom+xml FilterProvider COMPRESS DEFLATE resp=Content-Type $application/vnd.ms-fontobject FilterProvider COMPRESS DEFLATE resp=Content-Type $image/svg+xml FilterProvider COMPRESS DEFLATE resp=Content-Type $image/x-icon FilterProvider COMPRESS DEFLATE resp=Content-Type $application/x-font-ttf FilterProvider COMPRESS DEFLATE resp=Content-Type $font/opentype FilterChain COMPRESS FilterProtocol COMPRESS DEFLATE change=yes;byteranges=no </IfModule> </IfModule> We have a testing machine that runs the same Apache, OS and PHP version. On that machine the compression works just fine on the PHP output. I've checked and compared Apache and PHP config files, all the same as far as I can tell. I've tried several manners of outputting the content of the PHP, using output buffering or just plain echoing the content. Same thing, no compression. Example response headers of a PHP output: HTTP/1.1 200 OK Date: Wed, 25 Apr 2012 23:30:59 GMT Server: Apache Accept-Ranges: bytes Expires: Thu, 19 Nov 1981 08:52:00 GMT Cache-Control: public Pragma: no-cache Vary: User-Agent Keep-Alive: timeout=5, max=98 Connection: Keep-Alive Transfer-Encoding: chunked Content-Type: text/html; charset=utf-8 Example of response headers on a css file: HTTP/1.1 200 OK Date: Wed, 25 Apr 2012 23:30:59 GMT Server: Apache Last-Modified: Mon, 04 Jul 2011 19:12:36 GMT Vary: Accept-Encoding,User-Agent Content-Encoding: gzip Cache-Control: public Expires: Fri, 25 May 2012 23:30:59 GMT Content-Length: 714 Keep-Alive: timeout=5, max=100 Connection: Keep-Alive Content-Type: text/css; charset=utf-8 Does anyone has a clue or experienced the same "problem"? thanks!

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  • Free or inexpensive compression proxy

    - by Maksee
    Hi, I'm looking for a way to minimize the net traffic use with my netbook mobile internet connection. Recently I managed to install Opera Mini on the XP and the opera approach of compressing the data helped a lot. But I would like to do the same with my favorite browser using http proxy that compress the data "on the fly". But searching for "compression proxy servers" I could not find any working host/port links. Is it a brand-new technology and therefore expensive or rarely available?

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  • Highest compression for files(for web transfer)?

    - by Rogue
    Have seen some highly compressed files around.(for eg: i have seen 700mb of data compressed to around 30-50mb) But how do you get such compressed files, I have tried using softwares like Winrar and 7Zip but have never achieved such high compression. What are the techniques/software that allow you to compress files so well? (P.S. I'm using Windows Xp)

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  • Set compression level when generating a ZIP file using RubyZip

    - by Vincent Robert
    Hi, I have a Ruby program that zips a directory tree of XML files using the rubyzip gem. My problem is that the file is starting to be heavy and I would like to increase the compression level, since compression time is not an issue. I could not find in the rubyzip documentation a way to specify the compression level for the created ZIP file. Anyone know how to change this setting?

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  • Sql compression and backing up in sql server 2005

    - by cagin
    Hi there I want to backup my database with compression. This is my code : BACKUP DATABASE dbbbb TO DISK = N'C:\\dbbb.bak' WITH COMPRESSION this running correctly in Sql Server 2008. But my server has Sql Server 2005 and COMPRESSION is not a recognized BACKUP option in 2005. How can i compress my backup in 2005 Thank you for your helps.

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  • Partition Table and Exadata Hybrid Columnar Compression (EHCC)

    - by Bandari Huang
    Create EHCC table CREATE TABLE ... COMPRESS FOR [QUERY LOW|QUERY HIGH|ARCHIVE LOW|ARCHIVE HIGH]; select owner,table_name,compress_for DBA_TAB_SUBPARTITIONS where compression = ‘ENABLED'; Convert Table/Partition/Subpartition to EHCC Compress Table&Partition&Subpartition to EHCC: ALTER TABLE table_name MOVE COMPRESS FOR [QUERY LOW|QUERY HIGH|ARCHIVE LOW|ARCHIVE HIGH] [PARALLEL <dop>]; ALTER TABLE table_name MOVE PARATITION partition_name COMPRESS FOR [QUERY LOW|QUERY HIGH|ARCHIVE LOW|ARCHIVE HIGH] [PARALLEL <dop>]; ALTER TABLE table_name MOVE SUBPARATITION subpartition_name COMPRESS FOR [QUERY LOW|QUERY HIGH|ARCHIVE LOW|ARCHIVE HIGH] [PARALLEL <dop>]; select owner,table_name,compress_for DBA_TAB_SUBPARTITIONS where compression = ‘ENABLED'; select table_owner,table_name,partition_name,compress_for DBA_TAB_PARTITIONS where compression = ‘ENABLED’; select table_owner,table_name,subpartition_name,compress_for DBA_TAB_SUBPARTITIONS where compression = ‘ENABLED’; Rebuild Unusable Index: select index_name from dba_index where status = 'UNUSABLE'; select index_name,partition_name from dba_ind_partition where status = 'UNUSABLE'; select index_name,subpartition_name from dba_ind_partition where status = 'UNUSABLE'; ALTER INDEX index_name REBUILD [PARALLEL <dop>]; ALTER INDEX index_name REBUILD PARTITION partition_name [PARALLEL <dop>]; ALTER INDEX index_name REBUILD SUBPARTITION subpartition_name [PARALLEL <dop>]; Convert Table/Partition/Subpartition from EHCC to OLTP compression or uncompressed format: Uncompress EHCC Table&Partition&Subpartition: ALTER TABLE table_name MOVE [NOCOMPRESS|COMPRESS for OLTP] [PARALLEL <dop>]; ALTER TABLE table_name MOVE PARTITION partition_name [NOCOMPRESS|COMPRESS for OLTP] [PARALLEL <dop>]; ALTER TABLE table_name MOVE SUBPARTITION subpartition_name [NOCOMPRESS|COMPRESS for OLTP] [PARALLEL <dop>]; select owner,table_name,compress_for DBA_TAB_SUBPARTITIONS where compression = ''; select table_owner,table_name,partition_name,compress_for DBA_TAB_PARTITIONS where compression = ''; select table_owner,table_name,subpartition_name,compress_for DBA_TAB_SUBPARTITIONS where compression = ''; Rebuild Unusable Index: select index_name from dba_index where status = 'UNUSABLE'; select index_name,partition_name from dba_ind_partition where status = 'UNUSABLE'; select index_name,subpartition_name from dba_ind_partition where status = 'UNUSABLE'; ALTER INDEX index_name REBUILD [PARALLEL <dop>]; ALTER INDEX index_name REBUILD PARTITION partition_name [PARALLEL <dop>]; ALTER INDEX index_name REBUILD SUBPARTITION subpartition_name [PARALLEL <dop>];

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  • IIS7 Compression

    - by Thomas
    Hi Guys, I have searched around and havent really found an answer anywhere and this is still not working for me. I am using compression in IIS7 and it doesn't appear to be working. The code I am using is per <urlCompression doStaticCompression="true" /> <httpCompression cacheControlHeader="max-age=86400" sendCacheHeaders="true" expiresHeader="true" minFileSizeForComp="0" directory="%SystemDrive%\inetpub\temp\IIS Temporary Compressed Files"> <scheme name="gzip" dll="%Windir%\system32\inetsrv\gzip.dll" /> <staticTypes> <add mimeType="text/*" enabled="true" /> <add mimeType="message/*" enabled="true" /> <add mimeType="application/javascript" enabled="true" /> <add mimeType="*/*" enabled="false" /> </staticTypes> </httpCompression> However my content is still not being gzipped ? Any ideas why this is happening ? Cheers

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  • software for compression-decompression of pictures

    - by infant programmer
    I need to send hundreds of pictures via email. The size is reaching 100s of MBs .. which is certainly burden on network. WinRar, 7-Zip aren't helping .. Would you like to suggest any software which can carry out compression so that I can reduce the size and send it via email, and decompress it at the other end .. opensource or freeware are more preferred .. paid-versions are appreciated too Edit: I am seeking an alternative software for winrar and 7-zip which is more efficient in compressing .. but still not losing any data ..

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  • How do I reinforce compression options?

    - by Gooberpatrol66
    Shortly after I got my computer, I enabled NTFS compression on it, selecting the option to compress "all files and subfolders". I recently noticed that several folders on my PC are not compressed anymore, including "Program Files" and "Windows". I suspect this happened when I installed Windows 8.1. The problem is, the only way I can think of to fix this would be to uncheck the tick box under "Properties" for my drive, thus decompressing everything on my drive, and then re-check it with the "all files and subfolders" option. Is there a way to compress all the uncompressed folders without first decompressing the compressed folders?

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  • AAC 256kbit to MP3 320kbit conversion. I know it's lossy, but how?

    - by Fabian Zeindl
    Has anyone ever transcoded music from a high-quality aac to an mp3 (or vice-versa). The internet is full of people who say this should never be done, but apart from the theoretical standpoint that you can only lose information, does it matter in practise? is the difference perceivable, except on studio-equipment? does the re-encoding actually lose much information? If, p.e., high frequences are chopped away by the initial compression, those frequencies aren't there anymore, so this part of the compression-algorithm won't touch the data during the second compression. Am i wrong?

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