Compression decreases the size of data.

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2
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1answer
764 views

Windows “Send to Compressed (zipped) Folder [in different location]"

Is it possible to change the “Send to Compressed (zipped) Folder" functionality to create the zip file in a pre set directory, rather than the current one? Also, any information anyone can share ...
1
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2answers
126 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 ...
1
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0answers
1k views

7-zip command line -p switch not working according to help page [Solution Found]

I want to be able to automate the encryption of the file type .pcapng in a windows batch script. My current problem is that I get an error when extracting the encrypted file saying something along the ...
0
votes
1answer
64 views

How can I zip or rar file names in txt file from command line?

I'm using a batch script to output filenames with specific attributes to a .txt file, in this case older than 30 days. I'd like to then zip or rar those files that are listed in the .txt file. How ...
2
votes
1answer
117 views

Compress the silence - audio file formats

How do you compress audio silence? I'm using Audacity and have been exporting variable compression mp3s. But a 1minute audio track is about the same file size regardless of how much silence there ...
0
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0answers
118 views

Using hardware compression for webcam in Linux

I have a Logitech C615. I am assuming that if I configure mencoder just right, or perhaps v4l2, mencoder will use the native hardware compression of the web cam, and not try and decode and ...
0
votes
1answer
137 views

How to keep daily tar.gz backup with less redundant data

Like most of you, I have a few daily tag.gz snapshot of a folder (of any application). There is only a few different each other but the tar.gz is not a diff/delta friendly format. Most data in the ...
2
votes
3answers
702 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 ...
0
votes
2answers
197 views

Is there a ZPAQ implementaion that integrates with GUI compressors like File-Roller?

I've tried a number of ZPAQ implementations for Linux, but I don't like that they are all command-line programs, and thus require a lot of typing to get simple things done. My file browser supports ...
0
votes
3answers
144 views

What are good compression algorithms for delta synchronization?

When syncing large files over a slow link, it is often useful to use delta compression in order to reduce the bandwidth used. It is also useful to compress files as they take up much less space. ...
0
votes
1answer
90 views

Lossless screen video capturing

Can you capture/record a video playing on the screen using a recording software(or your custom code) such that every pixel is recorded and there is no loss of information ?
1
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2answers
191 views

Advanced backuping script

I'm currently writing an advanced starting script for my minecraft server. Everything works out as I want it too. But the problem is the backups. I created a function for it. It works also great and ...
0
votes
0answers
116 views

How can I get RAR to create a segmented archive (volumes) when compressing from stdin?

I have this ZFS box where I'm creating incremental snapshots, then piping them into RAR (4.2) for compression and encryption, and finally backing those files up remotely. Thing is, RAR seems to ...
0
votes
1answer
178 views

How do I install lzip/plzip?

A former developer backed up all of our files using plzip. We no longer have the server he used to compress them and have not been able to find a program to decompress these files. We have Windows 7 ...
0
votes
1answer
212 views

How to create ZIPs with the content of every folder [duplicate]

I have several folders and I need to compress the content of each folder in a separate ZIP file. However, every ZIP should only contain the content of each folder and not the folder itself. The ...
0
votes
0answers
24 views

Search file in compressed files in DOS

How can I search for files in compressed files using DOS? I know I can search for files with the dir command, like this: dir HtmlInputSecret.* /s But I don't think it searches in compressed files, ...
1
vote
1answer
613 views

7zip - compress the contents of each folder in a directory

I basically want to compress each file in each folder, delete the original file and leave the folder uncompressed. I don't want to compress the whole folder, only the contents in it. That, with 7zip ...
-1
votes
2answers
99 views

How compress the compressed file in unix

Is it possible to compress the file that is already compressed? Example: Given a compressed file such as file.zip, would it be possible to gzip it into another compressed file in UNIX like this: ...
1
vote
1answer
864 views

Chrome data compression proxy for PC

Google Chrome recently introduced data compression proxy which saves bandwith up to %50 in Chrome beta. (https://developers.google.com/chrome/mobile/docs/data-compression) Sadly it is only available ...
0
votes
1answer
96 views

How to store many files in one file without using compression

If I have a large set of small files it takes Windows a long time to copy them (say five minutes) due to the overhead per file. If I wrap them up in a container it transfers them much faster (say ...
-3
votes
1answer
176 views

Compress text file to tar.bz2 format on Ubuntu

How can I convert a sample.txt (uncompressed) file to sample.tar.bz2 format using Ubuntu 10.04 command shell?
0
votes
1answer
244 views

COMPACT /U command does not decompress large 25GB file

I have a 25GB file that was incorrectly set as NTFS-compressed because the directory where it is had been marked as compressed when it was created. I am trying to decompress it. The file is currently ...
1
vote
2answers
160 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
votes
1answer
54 views

Force gpg to use compression?

Odd situation, and I won't go into details about why our present circumstances require it. But, I'm looking for a way to force gpg to use compression. My testing is suggesting that the following ...
4
votes
3answers
2k views

Recursively unzip files where they reside, then delete the archives

I goofed up a setting on the backup software I use. Normally I would have the files from a network share get loaded into a spare drive, compressed into zip folders, then sent off to the offsite hub. ...
6
votes
1answer
4k views

How does 'dictionary size' affect compression?

I know that higher size may lead to better compression ratio and vice verca. But is there a way I can decide better?.. since there are so many choices So far I've noticed dictionary size ≈ file ...
1
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2answers
123 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 ...
1
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1answer
892 views

Video compression with ffmpeg - Constant quality

I am trying to compress videos of 10 seconds at different bitrates with ffmpeg. My aim is to obtain the same video at different qualities (from very low to very high). I don't want to touch audio part ...
-1
votes
2answers
348 views

Looking for a way to compress, encrypt, split, and upload data on Linux for backups to multiple clouds

As the title says, I'm looking for a way in Ubuntu/Linux to compress, encrypt, split, and upload data for backups across multiple clouds. I have grabbed multiple cloud accounts for free ranging ...
0
votes
1answer
1k views

avconv mkv to mkv with audio compression bug

In order to make quality tests, I would like to compress the audio part (to a low bitrate) of a matroska file without damaging video. Audio codec is AAC and video codec is H264. I am using avconv on ...
1
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2answers
95 views

How to extract such a compressed file?

I have been asked to extract a ZIP file having in it 3 tar files and each tar file contains around 3000 gz files. I had to extract the main ZIP file first then extract the tar files second then ...
0
votes
1answer
290 views

Windows: Automated PDF compression (Hot folder)

In Windows, is there a way to monitor a folder and automatically compress a PDF that is placed in it? (by compression, I mean make a PDF smaller (I.e. not zip it), similar to using the reduce file ...
0
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0answers
61 views

How to compress 2 (apple) disk images of different backups of the same drive?

So I have backed up my Macintosh HD at different instances to DMG files. I would like to compress them but when I try to make an archive it simply compresses each image, without recognizing the ...
0
votes
1answer
182 views

Differences between DMG and various Zip-like formats?

For my everyday work, I have a few DMG files that I keep on cloud storage. At the beginning of the day, I download my DMGs, convert them from Compressed to Read/Write using Disk Utility (OSX). At ...
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0answers
230 views

Compressing files over the network with WINRAR - read error

I have 3.6 TB of backup files on a NAS that need to stay together (they are a full and a months worth of incrementals - the latter is only useful with the former) - but I need to move them off the NAS ...
0
votes
1answer
40 views

What is “crossflow compression”?

I came across the term "crossflow compression" several times while reading about WAN optimization techniques. The only elaboration I've seen is that it refers to "compression across various flows", ...
0
votes
2answers
982 views

Zip many files into several archives

Running Linux. I have a directory of around 150 large CSV files; simply doing a zip -9 on them results in a monolithic file that is still too large. I would like it to simply zip them in maybe four or ...
0
votes
3answers
141 views

Untar multiple files at once?

I'm on Windows 7 and have a number of .tar files with the following names: .tar-aa .tar-bb .tar-cc ... The tar files contain a large backup directory which is broken up into chunks of 250MBs each. ...
-1
votes
2answers
123 views

Compress a remote folder in Linux

I'm a Linux newbie and I'm trying to zip a folder which exists on a remote host and export it to another remote host. A quick Google search lead me to tar/gzip and rsync options but I'm not sure how ...
0
votes
2answers
202 views

Good way to reduce number of colors in a PDF file?

I have pages of handwritten notes that I decided to scan to a PDF. Somehow, 153 pages of notes turned into a 156.4 MB PDF file. The notes are scanned in color because I used four different colors: ...
0
votes
1answer
358 views

Is it possible to recursively list zip file contents with 7 zip without extracting

Similar to this question I have a very large zip file which contains other zip files, folders, and files. I want to use 7-zip to extract a list of file names from it, recursing into subfolders and zip ...
3
votes
2answers
172 views

Is there a client impact to server side NTFS compression?

One of a our file servers at work is being compressed with NTFS compression. I've read about it being generally inadvisable on servers. But I've not found anything the states where the ...
1
vote
2answers
3k views

Compressed (Zipped) Folders no longer extract properly

I actually just finished up cleaning a virus from my computer (took me in total like 20 minutes, no big deal), but I'm almost sure this is what caused the problem. Now, whenever I download a zipfile I ...
1
vote
3answers
631 views

powershell create zip from log files

How can I move log files to zip archives with System.IO.Compression.FileSystem in PowerShell? I have more folders with log files per application: app1logfolder |-app1_20130507.log ...
0
votes
1answer
51 views

mod_deflate - possible to compress 1k or higher only? cache?

Is there a way to tell mod_deflate in .htaccess to only compress files if they are at least 1kb? Also, can it cache compression results? Once it compresses a file, I want it to use that again instead ...
1
vote
2answers
188 views

When compressing a file on command prompt with RAR command, how to stop the process without cancelling it?

I used the following command: rar a -m2 file.rar *.xml \\myroute\ I want to stop the process on the file that have already been processed i.e. using Ctrl + C will cancel the process but not finish ...
2
votes
0answers
133 views

Difference between lzip, 7z and zipx [closed]

I would like to know what is the difference between the algorithms used in these three compression schemes. I found that all three of them are based on LZMA. But I would like to know what makes them ...
0
votes
1answer
859 views

Can't view files from within WinRar (Win7 x64)

I have an issue with WinRar (64 bit version) on Windows 7 (x64) that is similar to the one described in another open question on this website Link to the same issue on this site (unanswered) However, ...
0
votes
2answers
388 views

What is the difference in various commands for compressing files in linux?

What are the commands for compressing files in linux and what are the difference between them? (for example: tar, gzip, rar). I'm working on Linux Mint 11 and doing a script for compressing files. I ...
0
votes
1answer
556 views

What compression algorithms are used by rar? [closed]

I am reading about many compression and archiving techniques.. I am not able to find the compression algorithms that are used by rar. Also I would like to know if rar compresses each file separately ...