How do I create binary patches?

Check out bsdiff and bspatch (website, manpage, paper, GitHub fork).

To install this tool:

• Windows: Download and extract this package. You will also need a copy of bzip2.exe in PATH; download that from the "Binaries" link here.
• macOS: Install Homebrew and use it to install bsdiff.
• Linux: Use your package manager to install bsdiff.

For small, simple patches, it's easiest just to tell diff to treat the files as text with the -a (or --text) option. As far as I understand, more complicated binary diffs are only useful for reducing the size of patches.

$ man diff | grep -B1 "as text"
       -a, --text
              treat all files as text
$ diff old new
Binary files old and new differ
$ diff -a old new > old.patch
$ patch < old.patch old
patching file old
$ diff old new
$

If the files are the same size and the patch just modifies a few bytes, you can use xxd, which is commonly installed with the OS. The following converts each file to a hex representation with one byte per line, then diffs the files to create a compact patch, then applies the patch.

$ xxd -c1 old > old.hex
$ xxd -c1 new > new.hex
$ diff -u old.hex new.hex | grep "^+" | grep -v "^++" | sed "s/^+//" > old.hexpatch
$ xxd -c1 -r old.hexpatch old
$ diff old new
$

This is a simpler, cleaner, better version suggested by bmaupin that uses process substitution instead of intermediate files, diff, and grep:

$ comm -13 <(xxd -c1 old) <(xxd -c1 new) > old.hexpatch 
$ xxd -c1 -r old.hexpatch old
$ diff old new
$

Here the comm -13 removes lines that appear only in the first input as well as lines that appear in both inputs, leaving only the lines exclusive to the second input.

HDiffPatch can run on Windows, macOS, Linux, and Android.

It supports diffs between binary files or directories;

Creating a patch: hdiffz [-m|-s-64] [-c-lzma2] old_path new_path out_delta_file

Applying a patch: hpatchz old_path delta_file out_new_path

Install:

Download from last release, or download the source code & make;

Jojos Binary Diff is another good binary diff algorithm;

diff and git-diff can handle binary files by treating them as text with -a.

With git-diff you can also use --binary which produces ASCII encodings of binary files, suitable for pasting into an email for example.

https://github.com/reproteq/DiffPatchWpf DiffPatchWpf DiffPatchWpf simple binary patch maker tool.

Compare two binary files and save the differences between them in new file patch.txt

Apply the patch in another binary fast and easy.

Now you can apply the differences in another binary quickly and easily.

example:

1- Load file Aori.bin

2- Load file Amod.bin

3- Compare and save Aori-patch.txt

4- Load file Bori.bin

5- Load patch Aori-patch.txt

6- Apply patch and save file Bori-patched.bin

alt tag

https://youtu.be/EpyuF4t5MWk

Microsoft Visual Studio Community 2019

Versión 16.7.7

.NETFramework,Version=v4.7.2

Tested in windows 10x64bits

Assuming you know the structure of the file you could use a C / C++ program to modify it byte by byte:

http://msdn.microsoft.com/en-us/library/c565h7xx(VS.71).aspx

Just read in the old file, and write out a new one modified as you like.

Don't forget to include a file format version number in the file so you know how to read any given version of the file format.