Compression decreases the size of data.

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is it safe to compress the File History folder?

Is it safe to compress the File History folder in Windows 8? Mine has grown rather big and a lot of the files types would compress well. However, I dont see any information on compressing it. It ...
2
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2answers
40 views

Is there a way to compress folders individually using 7zip on a large collection of folders?

How can 260 folders be zipped individually using 7zip with a single command? The person who originally asked this question voluntarily deleted the post. Since it was an interesting task, I ...
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0answers
19 views

Where are “supercompressors” used in the “real world”? [closed]

(Cross-post from Stack Overflow) I'm testing some "supercompressors" (PAQ8, PPMd, etc.) for academic purposes, and was wondering if they're used in some "real world" context. They are much much more ...
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0answers
11 views

General-purpose program for RLE compression

We have to deal with very large columnar files with fixed-size data and lots of padding bytes coming from mainframe. I would like to evaluate different compression techniques and their impact on ...
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0answers
13 views

Gzip Mutliple files using single command [migrated]

Want to Gzip my all the .csv files into a gzip file. I am using this command. gzip *.csv; Problem File contains '//' in its name that's why command is giving error. Error : - '//File.csv' is not ...
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2answers
28 views

Best format for compression of large amount of small files

I tried to use .rar and I get a great rate of compression. However it take a lot of time to show the folder structure when I open the .rar file (tried different programs), it looks it is needed to ...
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0answers
6 views

SASS e images not loaded

I have used webasset and cssmin on a python static site generator to merge 4 css files into a one compressed file. The individual CSS files when referenced individually does contribute to a fully ...
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2answers
35 views

7Zip Zipping up directories

I want to use 7 zip to compress and archive folders but I want it to exclude existing .7z files if they exist and not duplicate them with a .7z.7z ext I found this but it duplicates the already zipped ...
3
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1answer
29 views

How to dump and compress MySQL database in Windows only using command line

Is it possible to backup and compress just like in Linux: mysqldump --all-databases | lzma > all.sql.gz I only have smb:// and cmd.exe access via winexe, so no GUI (remote desktop is not enabled, ...
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3answers
125 views

How to reduce the size of windows OS Iso file?

I have an Iso file of windows 8.1 pro with December '14 updates. The problem is the file is too big to be burned on a normal 4.7GB DVD , its around 4.8. Now is it possible to remove a few updates so ...
114
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6answers
14k views

How is PNG lossless given that it has a compression parameter?

PNG files are said to use lossless compression. However, whenever I am in an image editor, such as GIMP and try to save an image as a PNG file, it asks for the compression parameter, which ranges ...
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0answers
34 views

Pacmd dynamic range compression Ubuntu 14.04

I used the answer at the link below to successfully set Dynamic Range Compression on my Ubuntu media box running Ubuntu 14.04 (SteamOS session, so no Ubuntu desktop session available). Realtime sound ...
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0answers
16 views

LZA Compressor Directory

I am trying to use LZA to compress my directories (No sub folders) Whenever I use it however it automatically creates the archive within an additional folder! Example: I am using a folder called ...
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0answers
22 views

How to modify files within mszip (cab) executable?

I can list and extract certain executable contents using 7z. It seems to be using standard compression methods. Path = test.exe Type = Cab Method = MSZip How can I modify files inside that ...
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1answer
66 views

Extracting a tar.gz file returns, “This does not look like a tar archive.”

I have a tar.gz file and I want to extract it using terminal. I used following commands: tar tvzf ldtp_3.5.0.orig.tar.gz and tar -xvzf ldtp_3.5.0.orig.tar.gz. However, I get the same result for both ...
0
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1answer
25 views

Is it possible to perform Deduplication recursively?

If anybody is familiar with the concept of Deduplication (If not,read link on wikipedia) http://en.wikipedia.org/wiki/Data_deduplication Is it possible to perform Deduplication recursively i.e. ...
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0answers
58 views

How do I access gzip-compressed data from a PowerShell Invoke-WebRequest command, when the “Accept-Encoding: gzip” header is set?

I'm learning about response compression in IIS and I'm testing my configuration with various tools. It appears that several of these tools either auto-decompress the response, or always send the ...
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0answers
33 views

Linux equivalent settings for 7zip

I'd like to use the same settings as below (Win7) on Linux to compress files, but I fail to get equal compression results, for which I blame myself not correctly using 7za. So far, I have 7za a ...
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4answers
92 views

Is it faster to compress files before copying? [duplicate]

I have around 80 GB of data I need copy to an external hard drive. Would it be faster to compress all the files first and then copy over? Or would the time it takes to compress and decompress take ...
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1answer
50 views

How is this RAR archive able to achieve such a good compression ratio?

The RAR archive found here (direct download) contains a single AVI video file which is 42MB in size. The RAR archive is only 500KB. How can the archive achieve such a high compression ratio?
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0answers
30 views

Changes in level of compression between different versions?

I used the save function with xz compression as in save(a, b, file = "c.RData", compress="xz") This produced a file of different size on my disk (11589212 vs. 1162284 bytes) switching from R.3.1.1 ...
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1answer
39 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: ...
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0answers
59 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
23 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
39 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 ...
3
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1answer
189 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
26 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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0answers
34 views

Which are good compression formats for an eternal version of a logfile? [closed]

I'm experimenting with logrotate and trying to set up an eternal version of a high volume logfile, e.g. /var/log/syslog, i.e. all entries should be preserved from the second the OS (Ubuntu 14.04) ...
0
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1answer
21 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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2answers
38 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
48 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
14 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
45 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 ...
0
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1answer
73 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 ...
1
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1answer
135 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 : ...
0
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3answers
53 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?
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1answer
41 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
16 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
938 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 ...
0
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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 ...
0
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0answers
19 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 ...
0
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1answer
46 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 ...
3
votes
1answer
441 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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0answers
23 views

Zpaq does not accept option “method”

I am trying to run the command: box:~/experiment# zpaq a out out.m4v -method 5 This should compress out.m4v to the file out using the method 5 but instead I get the error. -method: No such file ...
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1answer
1k views

7-Zip: Unsupported Compression Method while trying to extract a zipx file that consists of JPEGs

A zipx file I received consists of .csv files and .jpeg files. I used 7-zip to extract them. While the .csv files were sucessfully extracted, the JPEG files didn't. The error was something like this ...
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2answers
293 views

What does combining compression methods in 7z actually do?

The 7z command-line tool lets you specify multiple compression methods, e.g.: # 7-zip archive type, strongest (9) compression, methods PPMd, BCJ2, LZMA2 $ 7z a -t7z -mx=9 -m0=PPMd -m1=BCJ2 -m2=LZMA2 ...
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4answers
214 views

How to batch compress images with Imagemagick or similar command or program in Linux

I recently learned about the convert command from imagemagick which I have used to compress many pictures that I have for personal use, and for a blog that I have. In my experience, Imagemagick is the ...
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0answers
100 views

How to NTFS compress the system drive?

As you know, some files cannot be compressed when your system is running. How do I enable compression system-wide then? For every single file? Can I enable it in the recovery console? Ps.: For ...
0
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1answer
82 views

Should I compress the harddisk file in a virtual machine?

I have a virtual machine with Windows 7 32-bit installed, and the host is Windows 7 64-bit. I have chosen dynamically resizeable VDI disk image. After installing Windows on the disk image, it is about ...
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1answer
91 views

What 7zip settings to compress very large partition image?

I have 77 GB big partition backup image in single file and I'd like to compress it quickly. It should compress very well even on worst settings, but choosing GZIP with "Fastest" setting takes about ~1 ...