Zip compression levels

Show related SlideShares at end. WordPress Shortcode. Share Email. Top clipped slide. Download Now Download Download to read offline. Levan Chelidze Follow. Manual d'us 7-zip. Snp tables documentation. Publicidad 2,0. Related Books Free with a 30 day trial from Scribd.

My Mistake Daniel Menaker. The Writing of Fiction Edith Wharton. The Writing Life Annie Dillard. Related Audiobooks Free with a 30 day trial from Scribd. The Art of the Novel Milan Kundera. Elizabeth Howell. For this guide I am using 7-zip version 9. Fast Fast compression. Normal Recommended level of compression. Maximum Better compression, but it is slower and needs more memory. Ultra Best compression, but it is even slower and needs even more memory.

It provides high compression ratio and very fast decompression. It provides better multithreading support than LZMA.

But compression ratio can be worse in some cases. For best 3. If you use LZMA2 with more than 2 threads, 7-zip splits data to chunks and compresses these chunks independently 2 threads per each chunk. Usually it provides high compression ratio and high speed for text files. Usually it provides high speed and pretty good compression ratio for text files. Compression ratio is not too high. But it provides pretty fast compressing and decompressing.

Deflate method supports only 32 KB dictionary. Deflate64 Modified version of Deflate algorithm with bigger dictionary 64KB. When you change the value of Dictionary Size make sure that you will take a look at: Memory usage for Compressing and Memory Usage for Decompressing 5. Memory Usage for Decompressing: Make sure that on a pc you are planning on decompress this file has more Memory RAM than it is asking for 5 Word Size: Higher the value the better compression you are generally going to get however it is really dependent on files you are trying to compress You might get really big difference or might get nonexistent difference.

You should keep in mind that Word Size, might almost have no effect the size of a compressed file however it will always effect the speed of the compression so sticking to 64 is good practice 6. However extracting or adding a single file from an archive like this will take longer than none solid block compression. However the best practice is manually select the size of a block, for example if you are trying to compress 5 files and each file is MB you might select block size MB.

Improve this question. Is splitting the the zip in to multiple files an option? As soon as you pick anything but the Deflate format, it's not a "normal". They originally kept the extension as. If you can use LZMA, switch to. It's not even safe to assume that your recipient can handle deflate64, much less anything newer. Most "normal zip tools" nowadays like 7z and winrar can extract 7z files. Show 7 more comments.

Active Oldest Votes. Improve this answer. Bernd-L 1 1 gold badge 3 3 silver badges 9 9 bronze badges. Tek: Why? It's not a good one. This is a nicely formatted answer which is, unfortunately, wrong in multiple ways. I would use lzma2 — Lance Badger.

If you look at the 7-zip FAQ, it states that newer versions of 7z may have worse performance than older versions in some circumstances. Read the FAQ for more detail, but in short use the 'qs' in Parameters field in the GUI or use -mqs in the command line version to use the old sort by file extension method. Add a comment. For my archive, I experimented with a lot of other suggestions, including other answers here, and the best result I got was 99MB, vs 85MB using these settings.

How would you call this on Windows 10 in command line? I get "The parameter is incorrect" on version To run it on Windows, you must add the 7-Zip installation path to your system environment variable. Then you can use 7z inside Command Prompt. Show 3 more comments. Umber Ferrule Umber Ferrule 3, 8 8 gold badges 38 38 silver badges 54 54 bronze badges. For text such as log files, ppmd is definitely the way to go. However, the question mentioned that it needed to stay in the zip format, which may not work with PPMD.

I noticed that too. It opens the contents up just fine. However, when I actually tried to view one of the files inside the zip file, it failed. Why is PPMD superior compression method for text files? Show 1 more comment. The best combinations of parameters on several types of files were as follows: I note that the best values were not constant even for files of the same type.

I compare for db. Rob Kennedy Rob Kennedy 2 2 silver badges 12 12 bronze badges. I'm worried about how the people on the other side will uncompress the files. I need it to be as simple as possible for them. Do you know if you can unzip the split volumes using the built-in windows zip, or gzip?

Apparently, no, the built-in Windows zip-folder feature doesn't do spanned zip files. That's too bad, since it's been a standard feature of the format since before Windows 3. I'd be very surprised if gzip couldn't do it, though. WinZip definitely can. The Overflow Blog. Stack Gives Back Safety in numbers: crowdsourcing data on nefarious IP addresses.