Compression decreases the size of data.

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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 ...
0
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2answers
18 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
194 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, ...
0
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0answers
17 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
13 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
66 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
17 views

Windows software to copy from/to image/disk/partition with offset&compression [on hold]

I tried to put everything in the title : I'm looking for a software that is able : to work with image (raw file), partition & whole disk, without distinction to copy whole image or only ...
0
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1answer
17 views

Bulk resize / compress TIFF files [on hold]

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 ...
7
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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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1answer
28 views

Where can I find a _fast_ implementation of mscompress for Linux [on hold]

On windows, in the C:\windows\system32 directory there exist two small utilities, the compress.exe and the expand.exe executables. They have been around since MS Windows 3.1 days or so, but they are ...
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1answer
16 views

OS X software to compress images and reduce their size [on hold]

I have a hundred images sized 0.8 MegeBytes, resolution 640x1200. I need a software tool to compress them to 0.1 Megabytes or even less and decrease resolution, What software tools are there for this ...
6
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3answers
129 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
17 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 ...
6
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2answers
127 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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2answers
2k 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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votes
3answers
1k 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 ...
1
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1answer
48 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 ...
0
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1answer
14 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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4answers
37 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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1answer
29 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.
0
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0answers
34 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 ...
5
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2answers
825 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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0answers
11 views

WinRar 5.0 x64 Problems

Have several files on a flash drive that I use to help family members with their pc problems. However, I'm not able to open, extract files, extract here, extract to (filename), etc. One error ...
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3answers
893 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
141 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 ith a smaller one, such as representing a=abc b=def ...
0
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1answer
27 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 ...
10
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9answers
22k views

Highest compression for files(for web transfer)?

I have seen some highly compressed files around, such as 700MB of data compressed to around 30-50MB. But how do you get such compressed files? I have tried using software like WinRAR and 7Zip but ...
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3answers
16k 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 ...
6
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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 ...
12
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2answers
5k 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
44 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 ...
0
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2answers
42 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 ...
0
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1answer
213 views

Force all files in a NTFS compressed folder to automatically compress [Windows]

Is it possible to keep all the files within a NTFS-compressed folder compressed? For example, if I have a compressed a folder using NTFS compression, it will compress all the files inside the folder ...
20
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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 ...
34
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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?
19
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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 ...
3
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0answers
35 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 ...
1
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0answers
29 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 ...
42
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4answers
87k 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 ...
1
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0answers
173 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 ...
0
votes
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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4answers
9k views

How to obtain maximum compression with .tar.gz?

The way i understand the use of tar + gzip is that tar is normally used to consolidate a grouping of files into a single file, then gzip is used to compress that file. I recently learned that tar can ...
3
votes
2answers
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 ...
0
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0answers
22 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
votes
1answer
1k views

tar/bz2 compress a file removing uncompressed original

Is there any way to turn a directory called dir1 into dir1.tar.bz2 without keeping the original? I need to save space and want to compress some large files but don't have enough room to keep a ...
3
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1answer
39 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
130 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 ...
0
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0answers
18 views

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 ...
1
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0answers
48 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
67 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 ...