Compression decreases the size of data.

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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
357 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
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 ...
3
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1answer
587 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 ...
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1answer
54 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 ...
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5answers
4k views

How to open corrupted ZIP files?

How can I open (or repair) corrupted ZIP files on Windows? Is there a way to force 7-Zip to open them?
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3answers
203 views

When putting two identical files in a .zip, they take 2x space, can this be avoided

Say that you have a file you want to put in a .zip archive: zip a1.zip foo.dll My test .dll file is ~10MB, and the archive turns out to be 3.5MB Then you create a file with the exact same ...
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0answers
27 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 ...
7
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2answers
349 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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3answers
2k views

Disable Windows 8.1 Component Store (WinSxS/DriverStore) automatic compression?

Windows 8.1 has a new Scheduled Task (Servicing\StartComponentCleanup) which will automatically delete or compress superseded and unused files from the Side by Side store, DriverStore and drivers ...
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1answer
2k 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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1answer
16 views

Compressing with BarCat?

I'm having an issue using Barcat to show a dialog while compressing? Wondering what the exact syntax is? here's a link to Barcat things I've tried are bar -n apache24.tar.xz |tar -Jcf - bar -n ...
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1answer
53 views

Compress / Zip a folder periodically but use minimal CPU?

Similar to this question except, I need it to run with minimal CPU on the background? Also, if there's a 7zip solution that will be nice.
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0answers
127 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 ...
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2answers
915 views

Which compression program/algorithm produces the smallest archive file?

I have a directory full of *.avi files. I'd like to compress this directory into an archive of the smallest possible size. What compression software would produce the smallest archive file?
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1answer
95 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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3answers
20k views

How to highly compress files

I want to learn how to highly compress a file. I have downloaded files whose compressed size was 4 GB, and after extracting they became 10 GB. Which software do I need to use for such high ...
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1answer
2k views

Compressing a file in place - does “gzip -c file | dd of=file” really work?

In the question How can I compress a file on Linux in-place, without using additional disk space?, one answer proposes to simply use gzip -c file | dd of=file I tried it (on Debian Linux), and it ...
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2answers
6k views

How does file compression work?

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 ...
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1answer
100 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 ...
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2answers
139 views

Merging many .rar files in one .rar file

I have about 200GB of rar part files (all .rar) that I would like to merge into 1 single .rar file. I'm trying to perform this in Windows. How would one go about merging many a rar file without ...
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4answers
2k views

Can Double Zipping Cause Problems?

I have a directory that I have been storing a ton of files in. Among the 10ish types of files there are also .zips of other directories. In my personal experience I vaguely remember issues when ...
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5answers
3k views

Why is a 7zipped file larger than the raw file? [duplicate]

Possible Duplicate: Why doesn't ZIP Compression compress anything? I tried 7zipping an .exe file but it actually became larger. Is this the expected result?
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2answers
12k views

Is zip's encryption really bad? [closed]

The standard advice for many years regarding compression and encryption has been that the encryption strength of zip is bad. Is this really the case in this day and age? I read this article about ...
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0answers
43 views

Compressed file with a header containing all files within it, at the beginning of the file

I have noticed that most files resulting from a compression / archive process do not have a list of the files contained at the beginning of the resulting file, but rather at the end of it. For ...
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0answers
33 views

Store disc images on a hard drive

I'm cleaning up around my computer (A Win7 ultimate machine), and part of my plan is to rip all my program CDs and store them on a dedicated 1TB hard drive. My initial plan was to simply dump the ...
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0answers
177 views

How to unpack a compressed executable without knowing the compression algorithm

I'm not sure if this question was asked. I searched for it and could not find it. How can I unpack a compressed executable without knowing what compression algorithm was used to compress it? For ...
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1answer
2k views

Unpack NSIS executable

I am trying to decompress a NSIS executable. With the GUI version of 7zip I am able to do this and the exe is listed as: Type = Nsis Method = LZMA:25 Solid = + With the command line version 7za I ...
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0answers
39 views

Improve seeking precision for wma encoded in ffmpeg

Compressed audio formats (like compressed video) have trouble doing precise seeking. Is there something in the ffmpeg encode settings that I can change to make the resulting audio file allow more ...
3
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1answer
55 views

Is there any solution/utilities to compress and upload a large file simultenously?

Upload a large file via broadband connection takes time. Compress the file using max. compression ratio before upload also consume time. Is there any solution that may compress and upload file to ...
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2answers
400 views

How can I search for files that are either compressed or uncompressed in Windows Explorer?

I know that Windows explorer can colorize the NTFS compression state of a file, in both the regular and search views. How can I specifically filter/search for files that are compressed or ...
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0answers
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Compress whole internet session on all apps [duplicate]

As my main internet connection, I am currently using the USB tethering feature of my Android phone. My question is this: Can I compress my whole internet session in all apps (not only in Opera using ...
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0answers
93 views

Compress 1 TB file collection into standalone archives each size no more than 2GB

I have about 1TB data stored in two drives and I need to compress and encrypt them into independent archives each size must be smaller than 2GB. Exception may be files that are larger than 2GB. Is ...
0
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2answers
281 views

How can I achieve the maximum zip compression? [closed]

I would like to make a "standard" zip file which contain .jpg images. Which software and switches / options should I use to achieve the maximum compression ratio? I mean maybe I can make a solid ...
1
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0answers
122 views

Improve slow NAS Ethernet transfer speeds: On-The-Fly Ethernet Compression with SAMBA?

Hardware: Pogoplug E02 (ARMv5te, Marvell Kirkwood 1.2GHz, 256m RAM) Software: ArchLinux, MDADM RAID 5 array, Ext4, SAMBA server This setup delivers file transfers to my Windows clients at ~21MB/s ...
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2answers
355 views

NTFS compressed folders: is it possible to tweak compression ratio?

As it seems, Windows compresses the NTFS compressed folders with the lowest compression ratio possible. While this maybe good for increasing speed and decreasing CPU load, for the files that are ...
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5answers
3k views

Whatever happened to compressed read/write filesystems?

Back in the 90s, my home computer was an Acorn Archimedes. It had on it a piece of software called ArcFS, which allowed you to create compressed archives, a bit like zip files. Unlike zip files, they ...
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2answers
335 views

Compressing multiple files into multiple archives?

I have a folder full of pdfs and I'm tired of Winraring each file separately. I don't want to put them all in one archive. Isn't there a command line I can use to make Winrar compress a file with ...
2
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2answers
7k views

Untar a given linux tarball on MAC OS X

I have a Linux tarball that can't be unpacked. It gives me an unexpected error. I am told this is due to case insensitive on MAC OS X. How can I untar this file? tar -zxvf file.tar.gz ... x ...
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1answer
30 views

How do I back up images with limited disk space?

I'm in a scenario where I have one 500GB hard drive and about 400GB of images I want to tar. I obviously won't have enough disk space, but I don't mind getting rid of the images as they are added to ...
0
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0answers
49 views

Tape backup with compression

I would like to backup a NAS to a series of LT02 tapes, (200 gigs uncompressed, 400gigs compressed.) There are about 700 gigs of data to back up. I initially tried cpio, first trying to set hardware ...
0
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1answer
425 views

Recursively process zip archives to extract files while discarding specific format of files

On my Windows 7 machine, I have a directory full of downloaded dumps in ZIP archives. Each archive contains few text files, PDFs and rarely XML files. I want to extract all the contents of each ZIP ...
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4answers
6k views

How do I know the gzip compression level?

Given a gzip compressed file, how do I know what compression level (1-9) was used for it?
0
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2answers
71 views

I cannot open folders in .tar file

I've downloaded factory image for my Nexus4 mobile, the Image folder is compressed in .tar file but it tells me that its unknown file Type: File ,, how can i open it? here take some photo of my ...
2
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2answers
1k views

Creating .xz with 7-Zip, claims insufficient memory (not true)

In WinXP 32bit with a Core i5 (dual core) and 4GB RAM, I'm trying to create an .xz archive from a 266MB log file using 7-Zip (GUI) on the "ultra" compression level (method: LZMA2, dictionary size: ...
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3answers
71 views

Zero sized tar.gz file found inside a tar.gz file

My current directory contains a single file like this- $ls -l -rw-r--r-- 1 root staff 8 May 28 09:10 pavan Now, I want to tar and gzip this file like $tar -cvf - * ...
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1answer
45 views

How can I compress a series of integers?

BARF2 (Better Archiver with Recursive Functionality) generates a huge barf2.count file, which is a number-only file. What's the best way to compress that?
2
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2answers
249 views

Compress an attachment in my mailclient inside my INBOX?

I got a lot of emails with uncompressed formats (like bmp, txt, ...) that I want to keep inside my IMAP-inbox, so I can access them from all my devices (Windows, Linux, ios, Android). Those emails ...
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0answers
311 views

Cannot complete the compressed folder extraction wizard

Recently my friend archived a folder in linux (Redhat) and uploaded in Google Drive. I have downloaded the .zip file and trying in it to unzip in windows 7. I am receiving following error: Cannot ...