Questions tagged [compression]
Compression decreases the size of data.
309
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How can I compress video by taking advantage of its static content?
I have an HD video that is a presentation, so it consists mostly of still images. It's a 50 minute, 200MB MP4 file, downloaded from YouTube.
Is there a way to take advantage of the static nature of ...
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"Size on disk" column missing in Windows Explorer?
I decided to use the "compress this drive to save space" option on my backup drive, which simply houses a Windows Server Backup.
I learned that when viewing file properies for files on a drive using ...
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What is the difference in gzip compression levels?
Have been using gzip for a few years and usually I always gzip -9 out of habit as it is the highest level of compression. I understand that lower levels means less compression but quicker compress ...
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How to compress Tesseract-encoded PDFs while maintaining embedded text from OCR?
I've been experimenting with using Tesseract to OCR my PDFs, and it has been mostly successful, particularly with German Fraktur texts (the old style gothic print), which tools like Adobe Acrobat can'...
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How to get uncompressed content when using recursive wget?
i am downloading many single pages with all static content (js, css, imgs...) via wget recursive. It showed up, that served content, which was compressed (gzip), is stored by wget in compressed form. ...
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Possible bug in 7zip - empty folders extract as empty files
I have a directory structure as follows:
Main
|
|--empty_folder
|
|--folder
|
|--example.txt
I'm zipping it using the .NET ZipFile.CreateFromDirectory method (but I doubt this has anything to ...
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Gifsicle: How to set it to not overwrite the original GIF file if the resulting modified GIF file is larger than the original?
About Gifsicle:
Gifsicle is a command-line tool for creating, editing, and getting information about GIF images and animations.
One of its features is (from its website):
Optimize your ...
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Cannot zip a mutli-part archive, zip -FF command failing with out of memory error
Command zip -FF xxx.zip --out final_xxx.zip Fails with zip error out of memory or zip error : cannot split, read, write, file is too big.may be result of bad comrpression , try -fz
I do not how try ...
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Measure ram usage in Windows 10
I'm currently writing a report of an application and I want to know its memory usage.
Windows 10 has a nice feature that compresses memory that is not in process working sets in order to manage more ...
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Disable memory compression in Mac OS X for specific application?
Is there any way to disable the memory compression in Mac OS X for a specific application? I read how to disable it in general at Disable compressed memory in Mac OS 10.9 Mavericks? , but in my case ...
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What types of compressed archives does Microsoft Windows understand by default (Windows 10)
What file formats of compressed archives does Windows 10 natively know how to work with on fresh install?
There are many file formats for compressed archives. To name a few:
.tar.gz
.zip
.rar
.7z
etc
...
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Compressing pdfs
I've been using a web service at ilovepdf.com to compress some PDF files. And by some, I mean "several hundred to several thousand". The output files look identical (to my eye) and weigh in ...
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How to open a "Cached Theme.pak" in a Chrome theme CRX
I am able to open CRX files by changing the file extension to .zip, but when I am trying to get files that make up a theme, I can't find any. I'm assuming their in a file with the name "Cached Theme....
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Files corrupted after Defragmentation
This is my first post in this forum.
The Problem:
Today, I decided to defragment and optimise my 2TB external Hard Disk using Auslogics Defragmenter. Now, a little background here. The partition ...
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How can I get dictionary size of 7z archive using comand line?
I've got an 7z archive, I've read manuals but couldn't find how can I get dictionary size of this archive using comandline?
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"recompress" a 7z archive inline
I have a rather large (~500GB) 7-zip archive. I originally made it when I had more space available, and did so at rather fast, low-compression settings.
Now things are tight, and I'd like to try and ...
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Samsung 850 Pro SSD compression
I intend on buying the Samsung 850 Pro SSD, to use as an external drive via USB and I am wondering if it uses any kind of compression, like SandForce based SSD drives? I am fairly obsessive about data ...
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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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Why does 7-Zip's compression speed lower over time?
I'm busy backing up my local server files, which amounts to just under 4GB of data in ~295000 files. I selected 7z as the format, and set the level to Store.
The process started pretty quickly, but ...
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How to stop Word from rasterizing imported vector graphics?
I have various vector graphic images in PDF or EPS form (EPS is now only usable on Mac though), and they often contain embedded bitmap images and/or transparency.
When I import them into MS Word, they ...
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Compress a folder with internal complex folders tree and UTF-8 mixed languages files and formats for archive
I have a cloud folder on my hard-drive which I want to archive, in-order to do so I would like to compress it using best of choice compressor for that task :
Complex sub-tree of internal folders with ...
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Extract timestamp of I-frames of video using ffmpeg
If I understand correctly, I-frames are the frames that are unaltered during video compression. I want to extract the exact timestamps of these I-frames and save the output in a txt file. How do I do ...
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Lossless or near lossless compression options for PDFs containing grayscale with JPEG2000?
I have some older books (pre 1900) that I'm working on archiving to a digital format. Most of the time using greyscale is satisfactory in terms of color preservation, however I'm having trouble with ...
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Archive a big folder with large number of smaller and big files
I need to archive a folder from normal drive into tape in organization data storage and might retrieve them in the later stage. My scenario is
a large folder with size from 10 GB to 300 GB
The folder ...
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1
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Convert RAR to 7zip
To convert a RAR to 7zip archive the typical approach is to unpack the RAR archive and the repackage as 7zip.
Without unpacking and repacking is there a way to convert a RAR archive to 7zip format?
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How to set low priority while compressing with wzzip.exe
I have this in batch and the code works without start /low. While compressing with wzzip the CPU is 100% and all other programs hang.
So to fix this issue I've been trying to either set affinity or ...
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Compressing many similar small binary files independently using a preset dictionary
I have to compress many similar small binary packets (about 1.5 KB a packet) for data transmission. I tested .xz format on a 306 MB sample and I got 50% compression ratio (compressed to 153 MB). But ...
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Unusual behaviour with a passworded rar being invalid password in winrar but falsely accepted in 7zip
I found an old .rar file on my computer but I couldn't remember the password exactly. I had a rough idea of what it was, so I wrote a program using 7ziplib in c# to brute force a bunch of permutations....
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How to compress gif effectively to reduce size?
We use gifs for our blog extensively. We used to embed tenor nano gifs(90px height maintaining aspect ratio, used for GIF previews and shares on mobile) in it. Now we wanted to create our own gifs and ...
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Is it possible for a file system minifilter driver to interfere with NTFS compression?
On my work laptop I was running low on disk space and attempted to compress a folder using NTFS compression. The file properties dialog acted like it was compressing the folder but after it finished I ...
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I can't stop Windows 10 from compressing files when I download
I can't stop Windows 10 from compressing files upon download. I have gone into the command line (right click and run as administrator) and done
fsutil behavior set disableCompression
and then ...
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Compress PDF to 2MB or less
I have PDF files, tonnes (~1000) of them for a government report, varying from 600kb to 500MB.
Problem is that the portal only allows upload of files up to 2MB.
I have Windows (which I find fairly ...
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Extracting .dict.dz files on Mac OSX
I've tried to install dtrx on the terminal on Mac OSX and after downloading and extracting the the tarball from http://download.huzheng.org/ja/stardict-ej-edict-2.4.2.tar.bz2, it contains a .dict.dz ...
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Is data compression (V.42bis, V.44, MNP5) applicable for mobile broadband data connection (GPRS, UMTS, LTE)?
When using GSM (GPRS, UMTS, LTE) cellular network modems, there are options to control Data Compression (e.g. V.42bis, V.44, MNP5).
When using "modern" USB-dongles or telephones in modem-mode, is ...
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How to show uncompressed total physical size in bytes of an HFS-compressed file or directory?
Case in point: Apple's TextEdit at /Applications/TextEdit.app
If you calculate the physical size with echo "$(/usr/bin/du -k -d 0 /Applications/TextEdit.app | /usr/bin/awk '{print $1}') * 1024" | /...
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Is it possible to retrieve the compression level from a png image?
In my project we deal with png images. In order to create (encode) and read (decode) png images we use libpng.
From libpng it is possible to specify the compression level using ...
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Why does my image's quality go down when saving PPT to PDF?
In power point 2013, on the first slide I have this picture in PNG
Aftering saving the PPT to PDF it becomes
As you can see the image has became blurry around the edges of the letters.
Now this is ...
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Use pipe viewer when streaming directory through tar
I am currently streaming a directory over SSH after compressing it through tar:
tar cz /path/to/foo | pv | ssh HOSTNAME 'tar xmz && some-cool-command'
The issue is that pv doesn't know the ...
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Is there anyway to reduce bandwidth usage of Skype for business?
We use a lot of 'Skype for Business' (i.e. the new Microsoft Lync), that I use while consuming expensive roaming data. Was wondering, if there are options (similar to various VLC clients) that lead to ...
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Which files and folders are compressed when using compact.exe /CompactOS
I am thinking of using NTFS compression (LZNT1) on my SSD using Windows 7, but I was a little unsure as to which folders would be a good candidate.
I was aware that Windows 10 has introduced new ...
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How to change context menu option for 7zip?
I work a lot with .gzip format and I am wondering if there is a way to change the default "Add to" format in the context from .zip to .gzip.
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Unzip .gz file when line order is important
I am trying to unzip fastq.gz files and then analyze the sequencing data within them. However, later analysis is dependent on preservation of line (line 1 from zipped file must be line 1 in unzipped ...
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Stop Compression: Google Drive Videos?
Is it possible to stop the compression of Google Drive videos?
I uploaded an 18.4MB video in mp4, that was already compressed, and google drive added further compression, resulting in a block effect -...
user432683
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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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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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Safe to convert OS in .uif to .iso?
I'm being sent Windows 7 in a .uif format. Is it okay to convert it to .iso so it can be installed from a USB? If so, what is the best way to do that?
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Unzip speed on Mac versus Linux
I have a zip file that contains 200mb of data, compressed to an 80mb .ZIP file. Basically it's a website with thousands of files, including code and images, no video.
The file was zipped on a linux ...
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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 is....
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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 ...
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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 example,...
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