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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288
votes
9answers
508k 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 ...
102
votes
11answers
184k views

How can I reduce the file size of a scanned PDF file?

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.
98
votes
6answers
62k 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.* ...
52
votes
3answers
170k 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 ...
27
votes
5answers
20k views

Multi-Core Compression tools

What compression tools are available in Ubuntu that can benefit from a multi-core CPU.
25
votes
3answers
87k 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?
24
votes
4answers
54k 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 ...
23
votes
2answers
24k 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, ...
21
votes
3answers
13k 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
20
votes
6answers
14k 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 ...
19
votes
2answers
28k 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 ...
18
votes
4answers
7k 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 ...
16
votes
2answers
71k 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??
14
votes
3answers
4k 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 ...
13
votes
1answer
6k 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 ...
13
votes
3answers
21k views

How to reduce the size of a pdf file?

I'm looking for a way in Ubuntu to reduce the size of a pdf (by reducing the quality of the images). I know that this can be done in Ghostscript by typing the following command in terminal: gs ...
12
votes
3answers
8k 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 ...
11
votes
5answers
9k 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. ...
9
votes
3answers
10k 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).
9
votes
4answers
9k views

What is the best picture compression tool? [closed]

Is there a tool which can achieve good picture compression without losing the image quality in order to make optimal images for websites and can compress images in batches?
9
votes
2answers
26k 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 ...
8
votes
10answers
10k 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 ...
8
votes
1answer
2k views

Set 7z compression level using GUI in Ubuntu

Archive Manager, or file-roller, doesn't seem to have the option to set the compression level for 7z files. However, the windows client 7-zip has an option to do so using GUI - On Ubuntu/Linux, ...
7
votes
4answers
3k views

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

I need to store files in archives, but not compress them. The archive manager takes too long, and I can't find an option to only store (not compress) files. Any suggestions?
6
votes
4answers
23k 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 ...
6
votes
1answer
7k 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 ...
5
votes
5answers
4k 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 ...
5
votes
3answers
2k 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 ...
5
votes
3answers
13k 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 ...
5
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?
5
votes
1answer
766 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
749 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 ...
5
votes
2answers
975 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
2answers
230 views

Confusion between archiving and compressing?

I am confused about archiving and compression and I am going to write what I think is correct. Here are the commands that I wish to get a better understanding of: tar –c file > file.tar tar –cf ...
4
votes
1answer
292 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 ...
4
votes
2answers
583 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 ...
4
votes
2answers
2k 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 ...
4
votes
2answers
1k 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
2k 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
4
votes
1answer
2k 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 ...
3
votes
3answers
2k views

How do I compress multiple files into a .xz archive?

I want to compress several images into a .xz archive. How do I do that?
3
votes
2answers
2k 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
1answer
5k views

Xfce - GUI for File Compression?

If I remember correctly, using Nautilus in Gnome, I could simply right-click on a file & select "compress". Now I am using Thunar in Xfce & I can't find how to simply compress files... I ...
3
votes
1answer
294 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
1answer
4k views

btrfs and missing free space

I converted my ext4 partition to btrfs and deleted the save subvolume after doing so. Then I enabled the compression (lzo) of the filessystem in the fstab file and everything is correct so far. Then ...
3
votes
2answers
718 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
5answers
10k views

Why are the .zip files of compressed .jpegs about the same size?

I am a new user of Linux OS's and I am trying Ubuntu 12.10 right in this days. The overall impression is quite positive, but there are some features that make it still complicated for use from most ...
2
votes
2answers
3k views

btrfs for deduplication and compression at the same time?

I'm thinking about using btrfs functions for both deduplicate and compress my storage... My question is: is it efficient? I mean, does it deduplicate AND compress at the same time efficiently?! I'm ...
2
votes
3answers
927 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
2answers
127 views

Archiving a lot of files / one big file

I want to compress about 100'000 files (that's what find . -type f | wc -l says) with a total disk usage of 100 GB. Most of the files are small but just a handful of them makes up about 70 GB of the ...