How do I specify the compression level to gzip?

Is there a way I can specify the zip compression to "best compression" or "normal compression".

Answer 1

[Jan]

This is the core method:

function zipLevel(ZIPFile, FileList, Level)

import java.io.*
import java.util.zip.*
import com.mathworks.mlwidgets.io.InterruptibleStreamCopier.*

if nargin < 3, Level = 6; end

% Create output stream and set the level of compression:
try
   fileOut = FileOutputStream(ZIPFile);
catch
   error(['*** ', mfilename, ': Cannot open for output: ', ...
         char(10), '    ', ZIPFile]);
end
zipOut = ZipOutputStream(fileOut);
zipOut.setLevel(Level);

% This InterruptibleStreamCopier is unsupported and
%  may change without notice.
StreamCopier = getInterruptibleStreamCopier;

% Append files to zip file:
FileList = cellstr(FileList);
for iFile = 1:numel(FileList)
   aFile = FileList{iFile};
   fileIn = FileInputStream(aFile);
   zipObj = ZipEntry(aFile);
   zipOut.putNextEntry(zipObj);
   StreamCopier.copyStream(fileIn, zipOut);
   fileIn.close;
   zipOut.closeEntry;
end

zipOut.close;
fileOut.close;

This should be expanded by checking the the existence of file, getting the contents of folders and using a root folder for relative file names. Comments and file times can also be included by this method.

[raym]

Hi, I run your code and found that the filelist not compressed into the ZIPFile. instead, when I double click the zip file, it directly opens the D drive, and all the hard drive was indexed from here. But the file size is only 140kb.

Answer 2

[the cyclist]

I don't know how to do this, but if you type

 >> edit zip

you will get a bit more into the innards of the creation of the Java ZipEntry object, so maybe that will help.

Answer 3

[Friedrich]

Hi,

sry no you can't. At least without modifying the MATLAB Java code.