Windows 7 ISO Image Edition Switcher
Version 1.0
<http://code.kliu.org/misc/win7utils/>


Introduction
============

Unlike Windows Vista, Windows 7 is no longer "One Disc To Rule Them All", which
presents challenges to people who are downloading multiple editions from their
MSDN or TechNet subscriptions, and for people who want to backup and archive
their ISOs, because instead of just two disc images--one each for 32-bit and
64-bit--there are now eight different images.

This creates an unnecessary strain on bandwidth when downloading, wastes space
when archiving, and wastes time in general.

Fortunately, the images are all extremely similar, differing only in a handful
of bytes, so it is possible to create a binary patch that converts an image
of one type into an image of another type, and that is what this package does.


Usage
=====

The patches and patcher in this package can be used to convert any 32-bit image
into another 32-bit image and any 64-bit image into another 64-bit image.

For example, if you downloaded the 32-bit Ultimate ISO disc image from MSDN and
you also want a 32-bit Professional image, instead of spending another 2.3 GB of
bandwidth, you can make a copy of your Ultimate image and then patch that into a
Professional ISO disc image; the result should be exactly identical to what you
would have gotten had you downloaded the ISO image separately.

1) Run binpatch.exe
2) Select the the patch for the target edition that you want
3) Select the ISO disc image that you want to convert from
4) After patching, you should verify the SHA-1 hash of the final file and
   compare that with Microsoft's official hash to verify that the patch was
   successfully completed.


Notes
=====

The final patched file should be exactly identical to what you would have gotten
had you downloaded the file directly from Microsoft, and you should verify
that the hashes for the patched files match those posted on Microsoft's website.
For your convenience, a copy of the official hashes, in the standard sha1sum
format, has been included.

Converting to and from Enterprise is not supported because the Enterprise
edition installation discs are significantly different and cannot be be simply
patched.

Patches to convert to the OEM editions are not available because, except for
Starter, these editions have not been posted to MSDN or TechNet, and thus there
are no hashes with which to verify the correctness of such a patch.

binpatch.exe is a simple, general-purpose binary file patcher, and its source
code (binpatch.c) has been included for reference.
