Compression decreases the size of data.

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20
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3answers
70k views

What are the best options to use when compressing files using 7 Zip?

I often have to gather log files and upload them to a central server (Owned by another company). The central server has a size limit of the file, so I am trying to create the smallest file possible ...
8
votes
1answer
2k views

Hide NTFS compression blue double arrow icon overlay

Since the last Windows 10 update I have these blue double arrows on almost every item (all files & folders that are NTFS compressed). How can I remove these?
1
vote
1answer
18 views

How do .rar utilities manage to decompress a hidden compressed file (which is actually binary content appended to another file)?

After a puzzle in puzzles.SE which involved a hidden file appended to a gif, I have a question regarding appended .rar files. By this question I understand why I can add a .rar file content at the ...
0
votes
2answers
1k views

Does putting media files in archives help save space?

For example if you used WinRAR or Winzip on .mp3 or .wmv files would it save disk space? I thought the answer was no because the compression was already built into their encoding. But then I red this ...
0
votes
0answers
37 views
+100

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 ...
0
votes
0answers
10 views

How to compress ext4 partition with Acronis while backup?

With Acronis, when I set to compress ext4 partition before backup, the result is a raw backup and not compressed. The same process with NTFS or FAT32 partition, results are compressed. Please tell ...
1
vote
2answers
31 views

Removing pages from PDF doesn't reduce size

Have a PDF (20MB) with 10 pages. I'd like to cut the PDF in two parts of less than ~12MB (mail sending limit). created part1.pdf with pages 1-5 (6 to 10 removed) created part2.pdf with pages 6-10 ...
1
vote
2answers
662 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 ...
0
votes
1answer
20 views

Create Send-To-Compressed(zipped)-folder event shortcut on Windows10

I have a really simple question to which I haven't been able to find the right simple answer to. I'm working a lot with zipped (compressed) folders. I want to improve my workflow. After selecting all ...
16
votes
7answers
16k views

.tar files without directory structure

I'm .taring some files with the path example/super_user/Output.*. The resulting .tar looks like this: + example + super_user - Output.zip - Output.xml - Output.txt ...
25
votes
7answers
3k views

Why doesn't Gzip compression eliminate duplicate chunks of data?

I just did a little experiment where I created a tar archive with duplicate files to see if it would be compressed, to my awe, it was not! Details follow (results indented for reading pleasure): $ dd ...
1
vote
2answers
58 views

Batch compress .avi files with ffmpeg which contain previous date in their name

im trying to manage CCTV footage, and im trying to batch compress them with ffmpeg So far i managed to come up with this command ffmpeg -i "0515 210004.mp4" -b 200000 output.avi But i need to do ...
15
votes
4answers
12k views

Is it safe (or advisable) to compress Windows Installer folder via NTFS compression?

The title pretty much explains the question. Aside from the obvious (speed), is it generally safe or advisable to compress via NTFS compression the C:\Windows\Installer folder given that it's within ...
0
votes
1answer
21 views

Jpeg File Zipping does not compress at all

i'm trying to compress some jpeg photos, the total dimension is around 150MB, but when i try to zip it using the maximum compressing rate, i keep getting something around 150MB. I tried with Winrar ...
-1
votes
1answer
669 views

System and Compressed Memory: High Disk Usage

System and Compressed Memory is something I had for a long time Ever since I got this new computer, when starting up my computer, System and Compressed Memory (ntoskml.exe) has been using very high ...
1
vote
2answers
4k views

7-Zip command line -p switch is not working according to the help page

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
3k views

Split a folder of files into multiple zip files based on size or # of files

My problem is that the file uploader I'm working with will only allow a zip file with a size of 10mb or less. Unfortunately, I have thousands of files that need to be processed and I do this by ...
0
votes
1answer
24 views

Recompressing zip - integrity check

I have multiple large zip files and I would like to recompress them without unpacking them (I run the risk of running out of disk space). I am thinking of using advzip for that task. However, I want ...
1
vote
2answers
39 views

pg_restore fails on zlib compressed dump

Created a dump of a postgresql (windows version 9.3 or 9.4) database with the command: C:\>pg_dump -U user -Z 6 database > db.dump restoring it with psql or pg_restore fails: ...
0
votes
0answers
15 views

Convert a file from PNG to TIFF restoring TIFF Data

I have a software, that extracts TIFF data from a file and convert this file to PNG (TIFF has a default header with some bytes to be replaced on(width, height, stripbytecounts), so i replace those ...
2
votes
2answers
843 views

FFMPEG / libx264: How to specify a variable frame rate but with a maximum?

Instead of providing a fixed frame rate to FFMPEG/libx264 (-r/-framerate), I would like to specify a variable frame rate with a MAXIMUM value, and allow libx264 to down the frame rate as it sees fit. ...
1
vote
3answers
3k views

Is there an rsync alternative, that stores compressed and encrypted?

I'm looking for a suitable off-site backup / file synchronization solution. Both local client and remote server run linux. Storage space on the server is limited, bandwidth between client and server ...
2
votes
3answers
6k views

How do I compress a vmlinux kernel into vmlinuz?

The question is pretty much summed up by the title - I've just built a kernel which has generated the vmlinux output file. How do I compress this into a vmlinuz image?
0
votes
2answers
29 views

Can 7-Zip store the final archive to a custom path on a different partition?

I have a folder "D:/Tutorials/Exercise files" I want to compress "Exercise files" folder and put it on E:/Tutorials/ folder, that is on drive E: automatically from within the 7-zip program. Does ...
1
vote
0answers
586 views

Why does FFmpeg append blank black video to the end of my MP4 files when compressed from MOV?

I have several large MOV files that I want to compress to MP4. Unfortunately, when I use FFmpeg, it appends lots of black (blank) video at the end. (The destination file is longer than the source ...
3
votes
1answer
3k 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
votes
2answers
306 views

High compressed memory usage in Windows 10

I've been having problems on Windows 10: periodically I get a "low memory" warning. A lot of the Super User questions on this topic talk about driver memory leaks, but as I'll explain below mine ...
0
votes
1answer
29 views

Is there a way to toggle the Windows “compress this drive” command through a command prompt?

My friends laptop (a 64-bit Windows 7 Home Premium with 4GB RAM) was running slowly and she asked me to take a look at it. One of the things (besides that the disks had not been defragmented for a ...
0
votes
4answers
35 views

how to verify whether a compressed .gz is corrupted or not?

I have many gz downloaded from the internet, and I would like to make sure they are not corrupted. Does the fact that I can open the archive with winzip on windows proves that everything is fine? I ...
8
votes
1answer
5k views

How do I use the Google data compression proxy on Firefox?

I am using GNU Icecat (GNU version of Mozilla Firefox) on Trisquel GNU/Linux. In order to minimize/optimize data usage while web surfing, I want to use Google's data compression proxy. So, how do I ...
4
votes
2answers
333 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 ...
0
votes
1answer
80 views

OpenVPN Bad LZO decompression header byte: 69

On Arch Linux I run OpenVPN 2.3.9 server and I get this error "Bad LZO decompression header byte: 69" I run the client on a rooted Motorola XT1039 android lollipop 5.1 and I use official "OpenVPN ...
0
votes
1answer
2k views

Disabling “System and compressed memory” (ntoskrnl.exe)

I am very exhausted by this. This program is destroying my computer. I have an ASUS G750 series laptop, which has 16gbs of RAM and a haswell i7 inside it. It is just a year old. I upgraded from ...
0
votes
0answers
8 views

How to save as a Video-TS-BUP using DVDShrink

Using DVD Shrink 3.2 I compressed a video that had been converted from MP4 using ConverXtoDVD, however after it was compressed it appeared in my G drive in a format that would not play rather -by ...
0
votes
0answers
20 views

How does motion estimation work?

I am trying to understand the basics of video compression. I have found many resources addressing this particular subject, but somehow, I haven't clarified it yet on my mind. How does motion ...
0
votes
1answer
15 views

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?
1
vote
2answers
113 views

Guess compressability of a large file

I have a large file (~20 GB) and I want to quickly make an (approximate) estimate of how well it can compress. Searching for a program which can provide an immediate guess at the compressed filesize, ...
0
votes
4answers
66 views

How can I compress a large file on an already-full disk? [closed]

I have a full disk containing a large file that I want to compress to free up space. Most compression programs require me to have enough free space on the disk to store the compressed file alongside ...
2
votes
2answers
74 views

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 ...
0
votes
1answer
62 views

Creating a ZIP file that extracts cross platform

I need to distribute a large (6GB+) file cross-platform. For practical reasons, I want to zip it down to 2GB+. I originally used Mac OS 10.11 to create the zip file using the Archive Utility. It ...
2
votes
2answers
383 views

Zip all uncompressed file in a folder in one line

I have a lot of text files that I want to compress. Each file must be compressed separately. But some of them are already compressed. How do I, in one line, compress all files that end with .txt by ...
1
vote
2answers
67 views

Use ISO instead of ZIP or RAR to store files?

I have been doing some backups of my old files and lately I was wondering if there is another method of storing and compressing files other than ZIP or RAR. In my case, I want to store various group ...
0
votes
1answer
31 views

What are the disadvantages of using ultra compression?

7zip offers an option for ultra compression but I'm guessing that it has some disadvantages (other than being more time consuming) or else it would have been the default option... So what are they?
1
vote
1answer
77 views

lossless video using FFmpeg ffv1 on jpeg images is not compressed but expanded

Is it possible for FFmpeg / ffv1.3 / mkv to create a lossless video is not larger than the sum of its parts (and if so, how) and if not, what is a good alternative to come close on size? The video ...
1
vote
2answers
8k views

How to extract .arc files

I downloaded a software from the internet which is in .arc format. How can I extract the files on MAC? The arc file is 4GB, but I believe it will be 30 GB when extracted.
1
vote
0answers
100 views

IIS vs httpZip (or other product) Compression

We're currently comparing httpZip compression software. Has anyone used this and can offer a comparison between that product and IIS? Is there a big savings for httpZip over IIS? If you aren't ...
7
votes
4answers
5k views

Missing send to “Compressed (zipped) folder” after 1511 update or drag+drop to .zip

After allowing the Windows 10 1511 update to be applied, all options have disappeared from the right-click "send to" menu, except for "Bluetooth Device". Additionally, I can no longer drag and drop ...
3
votes
1answer
42 views

How easy is to recover uncompressed data if one sector is damaged in a 7zip archive?

I have around 100,000 small files which I backup every few weeks. Because they are really small, write speed to my external 2.5" USB 3.0 HDD is really slow. In 7zip, I compressed them using ...
1
vote
0answers
21 views

How can throughput be greater than the bandwidth? Is this a valid reason?

I asked this question on networking engineers but it was closed as off topic since it wasn't for professional application. Hope it fits better here. I'm studdying for the CISSP secuirty exam and a ...
1
vote
1answer
52 views

Cut and Compress 4K Video?

I have a 20 second video which size in 4K which size is 125 MB. It is only about a defective electronic component so accuracy is not important. I want it much smaller. I have these options in VLC ...