Compression decreases the size of data.

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722 views

Uncompressing files, compact'ed on Windows 10

I'm testing Windows 10 and one very interesting thing I found is new switches for compact: Displays or alters the compression of files on NTFS partitions. COMPACT [/C | /U] [/S[:dir]] [/A] [/I] [/F] ...
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1answer
829 views

ffmpeg: Highest quality 50i to 50p conversion, comparable to Adobe Premiere

I have 50i footage (more specifically tagged as 25 fps but does contain movement on the secondary fields). I am able to get pretty good quality conversion to 50p from Adobe Premiere by simply ...
2
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0answers
242 views

“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 ...
2
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1answer
407 views

Batch command to archive folders with content using WinRaR

I have lot of folders in the root "C:\Test\Archiv\" (more than 1000). To be more specific, I get one every hour. They are named as following : ay %year% m %month% d %day% h%hour% In each folders are ...
3
votes
1answer
862 views

7zip - Command Line: how to set output path?

I want to compress all HTM files in D:\HTM\ to an archive called comp.7z which is created in D:\HTM\ directory, so I do the following: 7z a -o "D:\HTM" comp.7z "D:\HTM" and get an error, exactly as ...
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1answer
57 views

Winrar self extracting SFX fail to launch

I created an SFX file (to unzip and launch a program directly) with Winrar which is supposed to be installed in a TEMP folder. I specified to launch "bin/myprogram.exe" after extraction. When I ...
0
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1answer
664 views

Winrar command line compression ratio

I have a Winrar command line that look like this: "c:\Program Files\WinRAR\WinRAR.exe" a -afrar -s -m5 "e:\output.rar" "e:\foldertozip" The folder that I am compress by default is 9.08MB. The ...
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1answer
57 views

How can compressed archives like .RAR be repaired?

I'm interested to know how WinRAR and 7-zip repairs archives but unfortunately I couldn't find any description about this process.So I'm here to ask: How does WinRAR or 7-zip repairing process work? ...
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2answers
214 views

How to create a zip file with files in FAT format on Linux

I have to create a zip file (with no compression). I want the files in the zip to be in FAT format. That is, If i use zipinfo command, I should get the following: ... -rw-a-- 2.0 fat ...
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1answer
47 views

accessing files directly from SFX archive

Similar questions have been asked on this forum, but not identical, so I am sorry if this is a bit redundant. I have made a "portable" application. I used WINRar to create an SFX self-extracting ...
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0answers
58 views

Why does performing OCR in Adobe create a much larger document?

I'm using Adobe Acrobat Pro XI on Macintosh OS X Yosemite and I've noticed that doing OCR sometimes creates a much larger document. For example, I scanned a four page document and got a 458K ...
2
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1answer
76 views

Slight file content difference due to LZW compression

In order to test if LZW compression is truly lossless I did the following: I created a master uncompressed TIFF file. Created an LZW compressed version of it Saved that compressed TIFF back into an ...
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0answers
331 views

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 ...
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0answers
33 views

wget only new or updated files when the source files are compressed but the destination files are uncompressed

I would like to know how to wget files from a url which are stored with bz2 compression. However, I would like to only wget the new and updated files, relative to my destination, where the files are ...
0
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2answers
71 views

Compressing a lot of similar JPEG images

I have a lot of—hundreds of thousands—JPEG images, and most of them are very similar to each other. While they aren’t of high quality and take about 100+ kB each, this adds up to a lot of storage. Are ...
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1answer
37 views

Inflate multi-file zip files in linux

I just downloaded some zip files that were splited. (The dreamplug rootfs files to be precise). They are called rootfs_dreamplug_v10_Aug-28-20128.zip.001 rootfs_dreamplug_v10_Aug-28-20128.zip.002 ...
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votes
1answer
90 views

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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1answer
471 views

Difference between pixz and xz with -T option

I'm trying to compress a 100GB with a good ratio, so I decided to use xz. I don't need it to be very fast, but since I have an 8-threads CPU, I was wondering how to take advantage of them. I found ...
3
votes
2answers
3k views

Is it possible to compress a full file system on Linux?

On Windows I can use NTFS drive compression to save heaps of disk space; usually 30%, often much more. It also improves read and write speeds at the cost of higher CPU usage; which isn’t an argument ...
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1answer
289 views

lighttpd complains about ssl.use-compression

I am trying to apply some of the tricks described here, and the problem is having ssl.use-compression = "disable" in lighttpd.conf, because server reports WARNING: unknown config-key: ...
0
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2answers
301 views

What files can I safely enable NTFS compression for on Windows 7/8 USB bootable drive?

The title says it all. I am just a few MB short of copying the needed files to a USB flash drive I intend to use for installing Windows. I have marked the partition as active. I was wondering if I can ...
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1answer
51 views

Does specifying the compression engine to tar directly actually use less intermediate disk space than tarring first and then compressing?

When I use tar to archive a directory and then compress it separately using e.g. xz, there will be a point where I have three files on my system - dir, dir.tar and dir.tar.xz. As soon as the ...
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1answer
85 views

What is the most common archive file format to have mountable, readable/searchable archives?

I make periodic backups of my data, resulting in large chunks of files. Currently I copy them into different directories on a share on a NAS (plus an external HDD), indicating the date in the ...
0
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1answer
232 views

Disk space usage in large folders with over one million files

I have a NTFS-compressed folder containing one to two million small (~25KB) text files. Recently, I noticed that far more space was being consumed than would be expected. Digging deeper revealed that ...
0
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1answer
409 views

dd , pv , gzip and exclude directory, possible?

Is it possible to do the following: dd if=/dev/hdx | pv | gzip > /path/to/image.img\ --exclude=/temp --exclude=/lost+found --exclude=/proc --exclude=/path/to/image.img So I want to make a backup ...
3
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2answers
142 views

How to tell of a GZip file is still being written while being copied

I am getting a gzip file in a path. Input Folder Path: <server>/input_gate I want to check whether the GZIP file I am getting in this folder are valid? I have used the following command. It ...
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2answers
179 views

Why don't iPhone or iPad compress the video they record? [closed]

I just recorded 30mins of video on an iPad (1080p, of course) and it took up close to 5Gb. So my question: is it really so hard to do on-the-fly compression? Surely that's what those multi-core CPUs ...
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1answer
1k views

Should Windows 8 be taking up 40GB of my HDD when my drive is compressed?

I want to install a game that requires 12GB on my computer with an HDD that shows 53GB total capacity, so I cleared everything off of it. All documents, pictures, downloads, desktop, etc empty ...
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1answer
317 views

restoring files after doing rsync with compression

I understand that you can rsync with arg -z and -a for compress and archive. Can someone tell me with these options, does it affect the files being backed up in any way if ever they need to be ...
0
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1answer
65 views

Why this scanned book image has no background?

If you save this image on your desktop, you see it's background color as your desktop color. If you open it with Adobe Photoshop, its background id checkered which means it has no background. It's ...
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2answers
30 views

Should I archive old folders

I have many folders on my hard drives that contain many media files and logs for old websites I have created for clients that I rarely ever access now. I want to know aside from compressing them what ...
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1answer
230 views

Uncompress bz2 file from command line on Windows

Is there any tool in the Windows command line that allows me to do this? Otherwise, is there any light and portable application that will allow me to? Related question, can I rename .bz2 extension to ...
0
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1answer
112 views

Does copying files via MTP over USB compress them?

I'm trying to backup my phone to a computer running Ubuntu 14.04 LTS, and I noticed that one of my backup images looked noticeably more pixelated, even when viewed at the same size as my phone screen. ...
3
votes
2answers
162 views

Is Gzip supposed to honor original filename during decompress?

This question stems from a Crypto++ library question on Stack Overflow: How to add filename to archive if compressing using Gzip class?. Gzip, as specified in RFC 1952 has an optional field for the ...
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votes
1answer
155 views

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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3answers
2k views

How to automate Adobe Acrobat XI Standard to re-compress a lot of PDFs?

I've about 15 gigabyte of PDFs scanned with an old version of Adobe Acrobat that are huge. Adobe Acrobat XI Standard that comes with my new scanner has an option to (it seems lossless) recompress ...
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1answer
204 views

How to batch compress sub subfolders?

I'm on Windows Server 2012 R2. I have a directory that looks like this: Folder01 Subfolder 1 File1 File2 File3 Subfolder 2 File1 File2 Subfolder 3 ...
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1answer
265 views

BTRFS filesystem, compression and copy on write

I'm planning about moving from etx4 to BTRFS filesystem on my pc and backup server. I'm very interested in the BTRFS snapshot feature (I have understood it uses the copy on write feature) and the ...
0
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1answer
539 views

reducing the size of PDF file of scanned images

I downloaded this PDF file from a website which is 350 KB in size with 20 pages. All pages are scanned images. I extracted the images using Adobe Acrobat Pro which are 1.32 MB in size collectively ...
0
votes
1answer
170 views

is it safe to compress the File History folder?

Is it safe to compress the File History folder in Windows 8? Mine has grown rather big and a lot of the files types would compress well. However, I dont see any information on compressing it. It ...
0
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1answer
425 views

Is there a way to compress folders individually using 7zip on a large collection of folders?

How can 260 folders be zipped individually using 7zip with a single command? The person who originally asked this question voluntarily deleted the post. Since it was an interesting task, I ...
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0answers
26 views

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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2answers
310 views

Best format for compression of large amount of small files

I tried to use .rar and I get a great rate of compression. However it take a lot of time to show the folder structure when I open the .rar file (tried different programs), it looks it is needed to ...
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2answers
119 views

7Zip Zipping up directories

I want to use 7 zip to compress and archive folders but I want it to exclude existing .7z files if they exist and not duplicate them with a .7z.7z ext I found this but it duplicates the already zipped ...
3
votes
1answer
2k views

How to dump and compress MySQL database in Windows only using command line

Is it possible to backup and compress just like in Linux: mysqldump --all-databases | lzma > all.sql.gz I only have smb:// and cmd.exe access via winexe, so no GUI (remote desktop is not enabled, ...
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3answers
6k views

How to reduce the size of windows OS Iso file?

I have an Iso file of windows 8.1 pro with December '14 updates. The problem is the file is too big to be burned on a normal 4.7GB DVD , its around 4.8. Now is it possible to remove a few updates so ...
131
votes
6answers
18k views

How is PNG lossless given that it has a compression parameter?

PNG files are said to use lossless compression. However, whenever I am in an image editor, such as GIMP and try to save an image as a PNG file, it asks for the compression parameter, which ranges ...
2
votes
0answers
412 views

Pacmd dynamic range compression Ubuntu 14.04

I used the answer at the link below to successfully set Dynamic Range Compression on my Ubuntu media box running Ubuntu 14.04 (SteamOS session, so no Ubuntu desktop session available). Realtime sound ...
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1answer
13k views

Extracting a tar.gz file returns, “This does not look like a tar archive.”

I have a tar.gz file and I want to extract it using terminal. I used following commands: tar tvzf ldtp_3.5.0.orig.tar.gz and tar -xvzf ldtp_3.5.0.orig.tar.gz. However, I get the same result for both ...
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1answer
56 views

Is it possible to perform Deduplication recursively?

If anybody is familiar with the concept of Deduplication (If not,read link on wikipedia) http://en.wikipedia.org/wiki/Data_deduplication Is it possible to perform Deduplication recursively i.e. ...