Yes. GZIP is a compression algorithm which both requires compressible data and has an overhead (framing and dictionaries, etc). An encoding algorithm should be used instead. The “simple” method is to use base-64 encoding. That is, convert the number (which is represented as base 10 in the string) to the actual series of bytes that … Read more
How about zlib? import zlib a = “this string needs compressing” a = zlib.compress(a.encode()) print(zlib.decompress(a).decode()) # outputs original contents of a You can also use sys.getsizeof(obj) to see how much data an object takes up before and after compression.
I’ve done some test using a Pickled object, lzma gave the best compression. But your results can vary based on your data, I’d recommend testing them with some sample data of your own. Mode LastWriteTime Length Name —- ————- —— —- -a—- 9/17/2019 10:05 PM 23869925 no_compression.pickle -a—- 9/17/2019 10:06 PM 6050027 gzip_test.gz -a—- 9/17/2019 … Read more
Try using Add-Type -AssemblyName System.IO.Compression.FileSystem instead. It is cleaner and does not have a dependency on the reference assemblies which need an installation of Visual Studio.
Using gzip.GzipFile: import gzip with gzip.open(‘input.gz’,’rt’) as f: for line in f: print(‘got line’, line) Note: gzip.open(filename, mode) is an alias for gzip.GzipFile(filename, mode). I prefer the former, as it looks similar to with open(…) as f: used for opening uncompressed files.
Take a look at this Stack Overflow question, the answers there contains references to multiple compressing engines implemented in javascript. Most of these are based on LZ77.
The boundary-pushing compressors combine algorithms for insane results. Common algorithms include: The Burrows-Wheeler Transform and here – shuffle characters (or other bit blocks) with a predictable algorithm to increase repeated blocks which makes the source easier to compress. Decompression occurs as normal and the result is un-shuffled with the reverse transform. Note: BWT alone doesn’t … Read more
You need to link it with the zlib library as well. Just add -lz to near end of your command line.
Use ZipEntry and PutNextEntry() for this. The following shows how to do it for a file, but for an in-memory object just use a MemoryStream FileStream fZip = File.Create(compressedOutputFile); ZipOutputStream zipOStream = new ZipOutputStream(fZip); foreach (FileInfo fi in allfiles) { ZipEntry entry = new ZipEntry((fi.Name)); zipOStream.PutNextEntry(entry); FileStream fs = File.OpenRead(fi.FullName); try { byte[] transferBuffer[1024]; do … Read more
Unfortunately, such a program does not exist. To see why this is so, we need to do a bit of math. First, let’s count up how many binary strings there are of length n. Each of the bits can be either a 0 or 1, which gives us one of two choices for each of … Read more