INTRODUCTION
-This is wimlib version 1.7.4-BETA (December 2014). wimlib is a C library for
+This is wimlib version 1.8.1 (May 2015). wimlib is a C library for
creating, modifying, extracting, and mounting files in the Windows Imaging
Format (WIM files). wimlib and its command-line frontend 'wimlib-imagex'
provide a free and cross-platform alternative to Microsoft's WIMGAPI, ImageX,
INSTALLATION
-To install wimlib and wimlib-imagex on Windows, simply download and extract the
-ZIP file containing the latest binaries from the SourceForge page
-(http://sourceforge.net/projects/wimlib/). You probably have already done this!
-
-To install wimlib and wimlib-imagex on UNIX-like systems (with Linux being the
-primary supported and tested platform), you must compile the source code, which
-is also available at http://sourceforge.net/projects/wimlib/. Alternatively,
-check if a package has been prepared for your Linux distribution. Example files
+To install wimlib and wimlib-imagex on UNIX-like systems, you can compile from
+source (e.g. './configure && make && sudo make install'). Alternatively, check
+if a package has already been prepared for your operating system. Example files
for Debian and RPM packaging are in the debian/ and rpm/ directories.
- WIM FILES
+To install wimlib and wimlib-imagex on Windows, just download and extract the
+ZIP file containing the latest binaries. See README.WINDOWS for more details.
+
+All official wimlib releases are available from SourceForge
+(http://sourceforge.net/projects/wimlib/files).
+
+ WIM FILES
A Windows Imaging (WIM) file is an archive designed primarily for archiving
Windows filesystems. However, it can be used on other platforms as well, with
some limitations. Like some other archive formats such as ZIP, files in WIM
-archives may be compressed. WIM files support multiple compression formats,
+archives may be compressed. WIM archives support multiple compression formats,
including LZX, XPRESS, and LZMS. All these formats are supported by wimlib.
-A WIM file consists of one or more "images". Each image is an independent
-top-level directory structure and is logically separate from all other images in
-the WIM. Each image has a name as well as a 1-based index in the WIM file. To
-save space, WIM archives automatically combine all duplicate files across all
-images.
+A WIM archive contains one or more "images", each of which is a logically
+independent directory tree. Each image has a 1-based index and usually a name.
-A WIM file may be either stand-alone or split into multiple parts. Split WIMs
-are read-only and cannot be modified.
+WIM archives provide data deduplication at the level of full file contents. In
+other words, each unique "file contents" is only stored once in the archive,
+regardless of how many files have that contents across all images.
-Since version 1.6.0, wimlib also supports ESD (.esd) files, except when
-encrypted. These are still WIM files but they use a newer version of the file
-format.
+A WIM archive may be either stand-alone or split into multiple parts.
+
+An update of the WIM format --- first added by Microsoft for Windows 8 ---
+supports solid-mode compression. This refers to files being compressed together
+(e.g. as in a .tar.xz or .7z archive) rather than separately (e.g. as in a .zip
+archive). This usually produces a much better compression ratio. Solid
+archives are sometimes called "ESD files" by Microsoft and may have the ".esd"
+file extension rather than ".wim". They are supported in wimlib since v1.6.0.
IMAGEX IMPLEMENTATION
files are converted from UNIX-style "man pages", they do document
Windows-specific behavior when appropriate.
- COMPRESSION RATIO
+ COMPRESSION RATIO
wimlib (and wimlib-imagex) can create XPRESS, LZX, or LZMS compressed WIM files.
-wimlib includes its own compression codecs and does not use the compression API
-available on some versions of Windows.
-
-I have gradually been improving the compression codecs in wimlib. For XPRESS
-and LZX, they now usually outperform and outcompress the equivalent Microsoft
-implementations. Although results will vary depending on the data being
-compressed, in the table below I present the results for a common use case:
-compressing an x86 Windows PE image. Each row displays the compression type,
-the size of the resulting WIM file in bytes, and how many seconds it took to
-create the file. When applicable, the results with the equivalent Microsoft
-implementation in WIMGAPI is included.
+wimlib's compression codecs usually outperform and outcompress their Microsoft
+equivalents. Although results will vary depending on the data being compressed,
+the table below shows results for a common use case: creating an x86 Windows PE
+image ("boot.wim"). Each row shows the compression type, the size of the
+resulting WIM file in bytes, and the time it took to create the file. When
+possible, the results with the Microsoft equivalent are included.
=============================================================================
- | Compression || wimlib (v1.7.4) | WIMGAPI (Windows 8.1) |
+ | Compression || wimlib (v1.8.0) | WIMGAPI (Windows 8.1) |
=============================================================================
| None [1] || 361,314,224 in 2.4s | 361,315,338 in 4.5s |
| XPRESS [2] || 138,218,750 in 3.0s | 140,457,436 in 6.0s |
| XPRESS (slow) [3] || 135,173,511 in 8.9s | N/A |
- | LZX (quick) [4] || 130,332,007 in 4.1s | N/A |
- | LZX (normal) [5] || 126,714,807 in 12.5s | 127,293,240 in 19.2s |
- | LZX (slow) [6] || 126,150,743 in 20.5s | N/A |
- | LZMS (non-solid) [7] || 121,909,792 in 11.9s | N/A |
- | LZMS (solid) [8] || 93,650,936 in 45.0s | 88,771,192 in 109.2 |
+ | LZX (quick) [4] || 130,207,195 in 3.8s | N/A |
+ | LZX (normal) [5] || 126,522,539 in 10.4s | 127,293,240 in 19.2s |
+ | LZX (slow) [6] || 126,042,313 in 17.3s | N/A |
+ | LZMS (non-solid) [7] || 116,150,682 in 25.3s | N/A |
+ | LZMS (solid) [8] || 88,107,484 in 61.7s | 88,769,830 in 102.3s |
| "WIMBoot" [9] || 167,023,719 in 3.5s | 169,109,211 in 10.4s |
| "WIMBoot" (slow) [10] || 165,027,583 in 7.9s | N/A |
=============================================================================
[8] '--solid' for wimlib-imagex. Should be '/compress:recovery' for DISM,
but only works for /Export-Image, not /Capture-Image. Compression chunk
- size in solid blocks defaults to 33554432 for wimlib, 67108864 for DISM.
+ size in solid resources defaults to 67108864 bytes in both cases.
[9] '--wimboot' for wimlib-imagex; '/wimboot' for DISM.
This is really XPRESS compression with 4096 byte chunks, so the same as
The compression ratio provided by wimlib is also competitive with commonly used
archive formats. Below are file sizes that result when the Canterbury corpus is
-compressed with wimlib (v1.7.2), WIMGAPI (Windows 8.1), and some other
+compressed with wimlib (v1.8.0), WIMGAPI (Windows 8.1), and some other
formats/programs:
=====================================================
| WIM (WIMGAPI, None) | 2,814,254 |
| WIM (wimlib, None) | 2,814,216 |
| WIM (WIMGAPI, XPRESS) | 825,536 |
- | WIM (wimlib, XPRESS) | 790,016 |
+ | WIM (wimlib, XPRESS) | 789,296 |
| tar.gz (gzip, default) | 738,796 |
| ZIP (Info-ZIP, default) | 735,334 |
| tar.gz (gzip, -9) | 733,971 |
| ZIP (Info-ZIP, -9) | 732,297 |
- | WIM (wimlib, LZX quick) | 704,006 |
+ | WIM (wimlib, LZX quick) | 690,110 |
| WIM (WIMGAPI, LZX) | 651,866 |
- | WIM (wimlib, LZX normal) | 632,614 |
- | WIM (wimlib, LZX slow) | 625,050 |
- | WIM (wimlib, LZMS non-solid) | 581,960 |
+ | WIM (wimlib, LZX normal) | 624,634 |
+ | WIM (wimlib, LZX slow) | 620,728 |
+ | WIM (wimlib, LZMS non-solid) | 581,046 |
| tar.bz2 (bzip, default) | 565,008 |
| tar.bz2 (bzip, -9) | 565,008 |
- | WIM (wimlib, LZX solid) | 532,700 |
- | WIM (wimlib, LZMS solid) | 525,990 |
- | WIM (wimlib, LZX solid, slow) | 525,140 |
- | WIM (wimlib, LZMS solid, slow) | 523,728 |
| WIM (WIMGAPI, LZMS solid) | 521,366 |
- | WIM (wimlib, LZX solid, very slow) | 520,832 |
+ | WIM (wimlib, LZMS solid) | 515,800 |
| tar.xz (xz, default) | 486,916 |
| tar.xz (xz, -9) | 486,904 |
| 7z (7-zip, default) | 484,700 |
and --without-ntfs-3g when building for Windows.
--without-fuse
- The --without-fuse option completely disables support for mounting WIM
- images. This removes dependencies on libfuse, librt, and libattr. The
- wimmount, wimmountrw, and wimunmount commands will not work.
+ The --without-fuse option disables support for mounting WIM images.
+ This removes dependencies on libfuse, librt, and libattr. The wimmount,
+ wimmountrw, and wimunmount commands will not work.
The default is --with-fuse when building for Linux, and --without-fuse
otherwise.
The WIM file format is partially specified in a document that can be found in
the Microsoft Download Center. However, this document really only provides an
overview of the format and is not a formal specification. It also does not
-cover later extensions of the format, such as solid blocks.
+cover later extensions of the format, such as solid resources.
With regards to the supported compression formats:
security descriptors and hard links, support for LZMS compression, and
support for solid archives.
* ImagePyX (https://github.com/maxpat78/ImagePyX) is a Python program that
- provides similar capabilities to wimlib-imagex. One thing to note, though,
- is that it does not support compression and decompression by itself, but
- instead relies on external native code, such as the codecs from wimlib.
+ provides some capabilities of wimlib-imagex, with the help of external
+ compression codecs.
If you are looking for an archive format that provides features similar to WIM
but was designed primarily for UNIX, you may want to consider SquashFS
such as device nodes and FIFOs. Actually, I use it to back up my own files on
Linux!
- LICENSE AND DISCLAIMER
+ HISTORY
+
+wimlib was originally a project started by Carl Thijssen for use on Linux in the
+Ultimate Deployment Appliance (http://www.ultimatedeployment.org/). Since then
+the code has been entirely rewritten and improved (main author: Eric Biggers).
+Windows support has been available since version 1.3.0 (March 2013). A list of
+version-to-version changes can be found in the NEWS file.
+
+ LICENSE AND DISCLAIMER
See COPYING for information about the license.
git://wimlib.net / wimlib / blobdiff