Compression decreases the size of data.

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112 views

tar reverse of '--to-command', or: compressing tar entries individually, or: tar with plenty of large files

I would like to create tar gzip archive, but do it the reverse manner of what is most commonly done -- have the files in the archive be compressed individually rather than compress the entire archive: ...
92
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4answers
187k views

How to decompress a .bz2 file

I have a file as: filename.bz2, but I can't figure out how to decompress it. I tried several methods, none of them seems work. I have tried the command: tar xvjf filename.tar.bz2, but it didn't work ...
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3answers
4k views

Between xz, gzip, and bzip2, which compression algorithim is the most efficient?

Between xz, gzip, and bzip2, which compression algorithm gives the smallest file size and fastest speed when compressing fairly large tarballs?
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4answers
180 views

What other archive formats save Date Created and Date Accessed?

7-Zip on Windows will save the Date Created and Date Accessed when compressing a .zip file, however it does not do this for its (referring to 7-Zip) native .7z format. Any Unix-based formats are ...
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2answers
8k views

What is the difference between rar and RAR5 compression?

What is the difference between rar and RAR5 compression ? Which is better for which purpose vs the compression time.
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4answers
1k views

Browsable compressed filesystem archive with full attributes?

Maybe a variation of the whole question would be: Are there any other archiving tools than tar that preserve Linux file permissions and user/group flags? I want to create archives of a directory tree ...
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0answers
147 views

Why do IPSec VPN Compression and Windows Remote Desktop not work together?

I just discovered a strange problem. I connect to a remote network via VPN. Within this VPN is a separate Microsoft Small Business Server (which does not provide the VPN, another device does this). So ...
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1answer
40 views

Deleting unpacked tar.gz files after unpacking incorrectly

I recently unpacked a set of backup files in RHEL3 - 2.4kernel with tar via: tar -xvf backupfile It started to error out a bunch and I aborted thinking that maybe it was a gzip instead. Unpacking ...
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1answer
85 views

How to open multiple TGA files then save them compressed as 24 bits in Photoshop?

I have a huge amount of TGA files from the game Counter-Strike (environment files such as sky, grass, water etc) and they are pretty big. There were some other TGA files that I manually opened and ...
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2answers
1k views

20GB+ worth of emails in my /home what is a better solution for that?

My email storage requirements are outgrowing anything reasonable with respect to local mail storage. As we speak 99% of my home partition is filled with personal mail in Thunderbirds mail dirs. ...
3
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3answers
2k views

zip: Argument list too long (80.000 files in overall)

I need to compress 80.000 files into multiple zip files. This is the command I use: zip -s 200M photos_test/* However I get the following error: -bash: /usr/bin/zip: Argument list too long What ...
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1answer
200 views

Not sure gzip has decompressed the whole file

I am decompressing a list of files using gzip: At any time it skips from one file to the next, I read (I am using the verbose option): star_60out.txt.gz: 91.0% -- replaced with star_60out.txt or ...
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0answers
77 views

Is there an alternative to httpfs2 to mount web urls in Linux?

Currently I use httpfs2 to mount direct web urls in the filesystem. For example a rar archive which has to be decompressed, but I don't have enough space on my VPS to download AND then decompress the ...
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1answer
98 views

How to have zpaq extract files to stdout

I have some log files compressed with ZPAQ that I do not want to extract to disk every time I need to go grep-ing for events. Would like to extact to stdout so I can handle the output the same way as ...
2
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2answers
432 views

7 zip archiving directory recursively

I zipped my old windows dir with 7 zip. It zipped the "Application Data" many time (hundreds) as shown here : C:\Windows.old\Application Data\Application Data\Application Data\Application ...
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5answers
12k views

.tar files without directory structure

I'm .taring some files with the path example/super_user/Output.*. The resulting .tar looks like this: + example + super_user - Output.zip - Output.xml - Output.txt ...
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5answers
5k views

How can I overwrite an existing file in 7zip?

I'm trying this: 7za.exe a "C:\Disc.7z" "C:\test" -v20000000b -m0=BCJ -bd But if I already have created the file C:\Disc.7z then 7zip doesn't compress anything and sends me this output: System ...
0
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1answer
23 views

Can i save modification in compressed file folder? [duplicate]

When modifying documents that are directly opened from compressed file folders like RAR or Zip, I normally close them without dragging the files out of the rar or zip file. I used to do this in the ...
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4answers
2k views

Should I compress hard drives containing large video files?

I have a media computer that stores large video/movie files of about 8GB per file... It is also used for media playback. Is it a good idea to compress the hard drives? how much space would I gain with ...
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2answers
180 views

How much can data be compressed? [closed]

Is there a scientific limit to how much data can be compressed? What I mean is, compression is essentially representing a larger amount of data with a smaller one, such as representing a=abc b=def ...
3
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3answers
379 views

Opening up a .tar file on Windows

What Windows tool or program can I use to open a .tar file? I also have .tar.gz files that I would like to open.
2
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1answer
1k views

how supercompressed iso files are working

I am recently seeing "Super Compressed" ISO files which have claimed to compress iso files to sizes < 15 mb, where the original file size is in 4GB+. How is it possible?
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2answers
138 views

Size of the compressed image file deteriorates with usage

I have created a VDI file using VirtualBox and need to upload it with compression for other to access. The more I use the virtual machine, the less the compression happens. There is not much of ...
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3answers
527 views

How big is an 800x600 image file in PNG? [closed]

How big is an 800x600 image file supposed to be in PNG? Actually what I would really like is a table that shows resolutions on the y-axis and formats/compression type on the x-axis. I ask this because ...
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2answers
513 views

How to further optimize PDF filesize?

I've been combining PDFs into a single file with Acrobat X Standard and have been able to get a 30-page document down to ~8MB. I've been seeing numerous similar documents that are just as, if not more ...
2
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1answer
265 views

Why do Mac apps increase so much in size on 'installation'?

I downloaded VLC 2.0 for Mac. It was a 42 mb download! The corresponding Windows installer is only 21 mb, despite the extra code for the installer itself. But even worse, when I open the VLC dmg, the ...
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4answers
8k views

Mac OS X not reporting directory sizes correctly?

In Finder, I've noticed that if I duplicate some .app files (in the Applications folder), Finder will show that the duplicate .app file is not the same size as the original. This file size ...
2
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0answers
366 views

Does a smaller cluster size increase the ratio of NTFS compression?

I read that NTFS compression needs a partition formatted with an allocation unit size <= 4KB. Could a smaller cluster size of a partition give more compression and lessen wasted space? For ...
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2answers
2k views

Reduce FLV file size

I have successfully converted an AVI file to FLV, but it's too large a file. How can I reduce it's file size without editing out any portions of its content?
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0answers
18 views

How to make to identical sized archive parts with rar archiver?

I am trying to compress a file with option -v but I am unable to figure out the byte count to set, yielding two identical sized archive parts (part1,part2). My original file size is: 1068303782 bytes. ...
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0answers
343 views

Why does FFmpeg append blank black video to the end of my MP4 files when compressed from MOV?

I have several large MOV files that I want to compress to MP4. Unfortunately, when I use FFmpeg, it appends lots of black (blank) video at the end. (The destination file is longer than the source ...
0
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3answers
64 views

decompressing a 50 GB archive to a 100 GB drive

So I moved hosts today and I put all content from the old host into a single archive. The archive took 20 minutes to compress and one hour to transfer the tar file to the new host (Linux CentOS ...
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0answers
57 views

True crypt container issue

I had created a true crypt container in my external HDD but stupidly ticked the "compress contents to save disk space" option from file properties. Now when I attempt to mount my container with true ...
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2answers
58 views

Determine type of archive file in Linux

I have an archive file with .tar.gz as extension grabbed from http://www.oracle.com (it is the Java Runtime Environment). I tried to decompress it using tar -xvf and tar -zxvf and it says gzip: stdin: ...
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3answers
32k views

How to set password on already existing winrar archive and encrypt it also?

Not when creating new archive, but on existing archive. I would also like to know how to do that in other archiver.
2
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2answers
394 views

Deduplicate Files inside multiple .tar.gz archives

I take a nightly backup from my Webhosting service as .tar.gz. The Data changed is very little each night (<10MB). I would like to archive these files and deduplicate (solid compression) files ...
0
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1answer
142 views

Create Compressed Back Up Image Mac Mavericks

I have a 3TB external drive, that for some reason is partitioned as a single Master Boot Record partition. Seagate, go figure. I'm running a 1TB Mac with 10.9.4 and about 380GB used space. My ...
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1answer
227 views

zip file (with spaces in the files name) to unzip and rename files and zip back

I'm trying to rename the contents of a zip file to match the name of the zip file with a batch file. This is exactly what I'm trying to do : ...
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4answers
1k views

What are the most popular file extensions for COMPRESSed files? [closed]

I was just wondering, what's the difference between these file formats? Shouldn't there be just one or two that generally tend to perform superior to most others?
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2answers
9k views

Convert old videos to have smaller sizes

I have some videos from a few years ago,with various formats, such as avi, mpg, wmv, rm, rmvb, .... Their sizes are huge(more than 500 MB, and sometimes > 1GB). Given there may likely be some ...
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3answers
76 views

Reduce bandwidth usage when web browsing? [closed]

If I have a 1GB tethering allowance per month. Is it possible to somehow compress the websites I visit so they use less bandwidth to reach my screen?
8
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3answers
39k views

What settings to use when making 7zip files in order to get maximum compression when compressing PDFs?

What settings to use when making 7zip files in order to get maximum compression? I'm compressing PDF documents containing scanned images. I'm thinking about using LZMA2, but I don't know what to set ...
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1answer
58 views

Creating a shell script to compress files using Cygwin [closed]

I've got a minor project wherein I'm to create a few shell scripts in Windows and run them through Cygwin for Linux files. At least that's how it was described to me. Any suggestions would be great.
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0answers
24 views

Is there any way to have the `split` utility gzip its output by default?

I'd like to be able to do something like, my_long_running_process_producing_lots_of_output | split --gzip --lines 1000000 - part_ and have this produce things like part_aa.gz part_ab.gz instead ...
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2answers
2k views

Cannot decompress .tar.xz file, getting “xz: Cannot exec: No such file or directory” from tar

Per How do I uncompress a tarball that uses .xz?, I tried tar xf php-5.6.0RC4.tar.xz and tar -xJf php-5.6.0RC4.tar.xz and in both cases I get the following: tar (child): xz: Cannot exec: No such file ...
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3answers
468 views

Check if HTTP calls are gzipped

Assuming that I have an application server (Linux) running on port 80, how can I make sure (with tcpdump, I guess) that all incoming requests are gzipped and all responses are gzipped as well? Also, ...
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0answers
19 views

Compressing an OS after some slight changes has yielded massively different results - why?

I am using SUSE Linux on a Virtual Machine through VMWare Workstation. This morning, I zipped up a copy of the folder containing my VM (.vmx, .vmdk, .vmem, single snapshot and all) and sent it to my ...
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0answers
20 views

Copy image/disk/partition, not necessarily entirely and with compression for image

As my last question was considerated "off-topic", here it is reformulated : I have a 16GB SDCard but I put 4GB image on it and I want to be able to extract&store compressed only the 4GB image ...
3
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1answer
942 views

Adobe photoshop “not enough ram” message opening a 60 MB TIFF file

I am working with Windows 7 x64 on a full HD monitor, Intel i5-2500K and 8 GB RAM, currently available 5,5GB. I tried to extend photoshop's memory usage and scratch disk settings as following: But ...
0
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1answer
83 views

Bulk resize / compress TIFF files [closed]

We support and host an EMR for several medical practices; these practices scan images into this software stored as flat files (TIFF mostly). Due to poor user training (people scanning text pages as ...