Compression is the process in which a file or folder's size is reduced by using an algorithm to encode the same information using fewer bits.

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90
votes
5answers
130k views

How do I uncompress a tarball that uses .xz?

I'm used to extracting tarballs with a -xfz flag, which handles gzip and bzip2 archives. Recently I've run into a .tar.xz file and I would like to uncompress it in one step using tar, how can I do ...
61
votes
6answers
24k views

What's the difference between .tar.gz and .gz, or .tar.7z and .7z?

Recently, I've been backing up a lot of my data, and I noticed that I can save files as .gz or .tar.gz, or .7z and .tar.7z, etcetera. What are the differences between the normal one and the .tar.* ...
35
votes
9answers
64k views

How to reduce pdf filesize?

I have a 72.9MB pdf file that I need to shrink into under 500KB. The file was a jpeg image that I had scanned, and then converted to pdf. Can someone please offer any suggestions?
15
votes
2answers
64k views

How do I compress a directory?

I'm trying to compress a directory and ftp it to a windows ftp. I have tried every tar command I can find to compress a directory. It appears to be ok. Then I transfer it and view it's contents ...
15
votes
2answers
7k views

Should I use xz or lzma compression?

I was wondering since in Ubuntu 10.10 I have the ability to create both xz and lzma archives. Should I switch to xz? http://en.wikipedia.org/wiki/Xz http://en.wikipedia.org/wiki/Lzma
12
votes
3answers
2k views

Any linux command to perform parallel decompression of tar.bz2 file?

I have a rather large file (~50GB) and it takes some time to run tar xvf file.tar.bz2 on it. I'm aware of programs that can do parallel compression for bzip2 files but unaware of programs that can ...
12
votes
4answers
3k views

Compress and split files in Nautilus

If you right click a file in Nautilus and select Compress, then you get a dialog where you can choose a compression format and a filename. If you click on Advanced, then there are settings to split ...
10
votes
5answers
6k views

Will btrfs automatically compress existing files when compression is enabled?

I chose btrfs as the format of my / filesystem in the Ubuntu 12.04 LTS installer. After the installation completed, I added compress=lzo to the mount options in /etc/fstab and rebooted. Will the ...
9
votes
3answers
2k views

How can I compress an mp3 file?

Well that is my question! i used to download a program in windows that used lame to compress audio of mp3 files and made them shorter in size but I don't know how to do this in ubuntu! Does anybody ...
9
votes
1answer
3k views

Is there a way of leveling/compressing the sound system-wide?

As a Laptop user, I'm sure that a lot of people, even the ones using Netbooks would have already gone through this problem. Especially when listening to podcasts, and using it as an example, the sound ...
8
votes
4answers
11k views

What's the easiest way to unrar a file?

I just realized I can't unrar .rar files on my Ubuntu machine! :) What's the easiest way to accomplish this fundamental task? If possible I'd love something like 7Zip that I can just right Click, and ...
7
votes
5answers
3k views

Multi-Core Compression tools

What compression tools are available in Ubuntu that can benefit from a multi-core CPU.
7
votes
5answers
3k views

Command line archive manager / extracter

I keep forgetting all the corresponding extract commands for every compression format. So I was thinking about writing a script that merely maps file extensions to the appropriate extract command. ...
7
votes
1answer
5k views

Best compression method?

I want to compress a 16GB folder, but what's the best method? tar.gz? tar.bz2 rar? 7z? Would the archive be smaller if I first compressed in a method, then copy the compressed archive to a new folder, ...
6
votes
9answers
8k views

Trick installer to use btrfs root with compression

I want to install Maverick onto a BTRFS root partition. Not for fun or testing, but because I need compression due to a small flash disk (4GB). Now the 10.10 installer finally supports btrfs, but ...
5
votes
4answers
1k views

How can I store files in an archive without compressing them on Ubuntu 10.04?

I need to store files in archives, but not compress them. The archive manager that comes with Ubuntu 10.04 takes too long, and doesn't have the option to only store (not compress) files. Any ...
5
votes
3answers
10k views

how to extract tar.7z files from command line? [duplicate]

Is there a way to extract files of tar.7z format using command line tools in Ubuntu?
5
votes
4answers
12k views

How can I maximum compress video files?

I received 4 .mov files from a client that they want on their mobile website via SlideShowPro. Each original file was between 200 and 400 mb. I've gotten each one down to about 30 mb using ...
5
votes
1answer
296 views

How to archive with ignoring files larger than 100MB

I'm trying to archive files with tar and ignoring files larger than 100MB. Is that possible? PS: Not have to use tar.
5
votes
2answers
314 views

How to decompress and access a 10 year old ACE file?

I'm trying to unarchive some old photos I have that are stored in ACE format (via WinACE). The file was created a little over 10 years ago. I'm running unace l photos.ace and getting what seems to be ...
4
votes
4answers
609 views

What is the difference between different “compression” systems?

I've always used TAR and ZIP for compression, but recently I have heard about the *.Z compression algorithm. This brought up a question for me: With all of these compression systems, which one is ...
4
votes
3answers
857 views

What's the difference between a compressed folder (with files) and a compressed Tar archive?

I don't understand the use of TAR. My understanding is it pulls together many files into one file. But doesn't putting files in a folder do this? Using ZIP, I put files I want to archive in a folder ...
4
votes
3answers
6k views

How to install rar (no installation candidate)?

I need the package rar. But I get this error whenever I try to install it: Reading package Lists... Done Building dependency tree Reading state information... Done Package rar ist not available, but ...
4
votes
2answers
3k views

How do I create tar.7z file from the command line?

I would like to zip up my homework from last year. How do I tar and zip the whole folder from command line Ubuntu (I don't have GUI).
4
votes
2answers
19k views

Compress in .tgz

I want to compress files in .tgz. I know how to make tar.gz(with tar and gzip) and some people say it is almost the same, but I need to make a .tgz, how??
4
votes
2answers
2k views

Change default compress option in Nautilus type to zip?

On the right click menu (in Nautilus, desktop, etc), there is a "compress" option. Is there any way to make "zip" the default format for this?
4
votes
3answers
1k views

Minify tool that can be executed through terminal

I am looking for a tool or a way to minify (similar to Compress my code and this question on Stack) all of the code in my .xml, .css, .html and .js files through Ubuntu's terminal. Eventually I will ...
4
votes
2answers
954 views

How can I maximally compress .gz files in Nautilus?

When selecting Compress... from the right click context menu in Nautilus I am able to quickly compress files to .gz format. However by default Nautilus does not use maximum compression. Can I make ...
4
votes
2answers
656 views

Is it safe to remount btrfs with compression?

I've finally found how to enable compression in btrfs, and would like to do so. However, as my main drive, I'm not really wanting to risk a change that could corrupt the hard drive. Everything I've ...
3
votes
2answers
1k views

Should I install zip or use gzip?

I have downloaded some .zip files. I wish to decompress them (I have unzip), modify them, and compress them again (into separate compressed files, one decompressed file per compressed file). I have no ...
3
votes
2answers
9k views

How to extract files from a split 7zip archive?

I downloaded a series of packages that all compress one thing. The files end in .0, .1, .2, etc. The User Lists of these packages I downloaded say to use the file.bat to successfully extract, or to ...
3
votes
3answers
3k views

What is the best picture compression tool?

Is there a tool which can achive good picture copression without loosing the image quality, and which produced optimal images for websites and can compress images in batches?
3
votes
2answers
3k views

Compressing folders with password via command line

I would like to know whether it is possible to do the following via CLI. I have a Folder F which contains several sub folders and some files. I want to compress folder F into .zip file with the ...
3
votes
1answer
136 views

Screenshot tool with integrated optipng or pngcrush

This is a followup question of how do I get maximal compressed screenshots? Is there a screenshot tool that has optipng or pngcrush already included to minimize the filesizes of the png ...
3
votes
2answers
168 views

how do I get maximal compressed screenshots?

I'd like to compress my screenshots as much as possible before I send them via email. The best compression ratio I only got with some work on each screenshot: first I took the screenshot with ...
3
votes
1answer
231 views

How do I set ubuntu to compress a series of folders , deleting the original after its been compressed?

I need to setup some kind of script to go through a set of folders, compressing each one, and only leaving the compressed copy of each. How can I do that?
3
votes
2answers
753 views

Which Compression Format will give the least size

Hi i have a few GBs of files which i am supposed to burn to a DVD for permanent storage, which compression format will give me "LEAST" size, thanks
3
votes
1answer
532 views

Side Chain in Ardour

Can someone familiar with Ardour 2.8 please make a video / youtube guide showing precisely how to use SC3 Side Chain Compression? I've read every guide online currently and side chain is simply not ...
2
votes
3answers
433 views

Why is the default wallpaper in jpg format, rather than a lossless format like png?

Is it just to save disk space? Or does it effect loading time/performance in some way? You'd think that you'd want the best quality possible image for something you'll be looking at throughout the ...
2
votes
1answer
420 views

Extract an .mzp on Ubuntu

As above, is there any way to perform an extraction of a .mzp file on Ubuntu? The interwebs have nothing for me :p.
2
votes
1answer
2k views

Simple Scan - Changing the default output File Type to PDF and improving Compression?

Is there a way to change the default output file type in the 'Simple Scan' software provided with Ubuntu 12.10 to be a PDF rather than a JPEG? And is it possible to modify the compression settings on ...
2
votes
1answer
1k views

How do I compile mod_deflate?

I want to enable compression in apache. For the same I am trying to use deflate module of apache. I have already installed apache 2. But it is a default installation and in that mod_deflate is not ...
2
votes
1answer
2k views

Gzip and rename (remove .gz extension) all files except images and PDFs?

I am able to gzip every file in a directory (mydirectory) using the command: gzip --suffix .gz --recursive mydirectory But... I don't want the images (.ico, .jpg, .png, .gif) and PDFs (.pdf) ...
2
votes
1answer
817 views

How do I open/extract .xdi file on (x)ubuntu?

Downloaded a bunch of books which were compressed in a .xdi file. How do I open/extract the internal data/files? I go to open, and Ubuntu does not recognize/nor is there a seemingly effective ...
2
votes
1answer
1k views

Optimize video filesize without quality loss

Is there a simple way (on the command line - I want to write a script which compresses all videos in a folder) to reduce the filesize of a video (almost) without quality loss? Is there a method which ...
2
votes
1answer
780 views

An error occurrend while adding files to archive

I am trying to compress and backup my /var/www/. I stopped apache, but I still get this error: An error occurrend while adding files to archive
2
votes
1answer
43 views

Compressing many folders

I have a directory containing plenty of folders as well as compressed files. I need to compress the folders that are not already so (tar -cvzf ...) but have no experience in sh scripts. Can anyone ...
2
votes
1answer
66 views

Rsync-ing highly compressible files - am I missing something here?

Today I was using rsync over a slow internet connection to transfer a video file - uncompressed avi, 60 seconds duration, 360MB in size. Basically it contained 1500 frames of the same image, hence it ...
2
votes
1answer
2k views

How to read/mount a .gz.dd image file?

I have a partition file (a .gz.dd file) that I need to read the files from. I'm new to Linux and I don't know how I can read/mount .dd files in Ubuntu. Would you guys tell me the procedure of reading ...
2
votes
1answer
507 views

ramdisk, compressed, writeable, no swap

I need a ramdisk who handle transparent realtime compression on write and decompression on read. Example : I use /dev/shm, or I create a new tmpfs, mount it writeable and compressed. I wrote and ...