RapidCRC Unicode

RapidCRC is an open source CRC/MD5/SHA hashing program. I've extended the current unicode support to allow writing of unicode .sfv/.md5/.sha1/.sha256/.sha512 files, which can be turned on/off through the settings page. Unicode sfv files are written as UTF-16LE with BOM or UTF-8 (with or without BOM), and RCRC now performs a codepage detection. I've also expanded the shell extension that was included in the sourcecode to enable all operations directly from the extension.

List of other new features:

  • multithreaded hash calculations with asynchronous I/O
  • ed2k hash calculation
  • SHA hash calculation
  • job queueing
  • popup menu to copy the calculated hashes to the clipboard

RapidCRC is released under the GPL - the sourcecode with my modifications can be found below. Be warned however that my documentation in the sourcecode is not as good as the original RapidCRC source.

LM from www.portablefreeware.com made a nice introductory video about RapidCRC:
YouTube Link



posted on 10/11/2012 - 01:15
  • added sha256/512 support (hash calculation and file verification)
  • fixed reparenting


posted on 09/14/2012 - 00:46
  • fixed "one checksum file per dir" mode
  • file comments now work in all modes


posted on 09/11/2012 - 21:52
  • fixed 64bit build
  • support for path longer than 255 characters
  • column sort direction displayed in column header
  • optional file comments with size and modification time
  • updated status display, is now always present and updated during job processing
  • add option to force utf-8/system codepage


posted on 05/27/2012 - 22:49
  • Fix button sizes pre vista, reduce control flicker on resize
  • Add listview context menu option to hide verified files


posted on 03/19/2012 - 16:15

This is simply a rerelease post of 0.3.3 on the new site.

Old site info

posted on 03/19/2012 - 16:03

Update (29.12.2011):
The initial 0.3.3 release contained a small bug in the shell extension where it would not display on all file extensions. The installers and archives have been updated to fix that. If you've downloaded the version prior to today, uninstall through the control panel and redownload the fixed installer. Alternatively you can try to replace the shell extension dll with the updated archive.

Update (23.12.2011):
* fix shell extension submenu leak
+ add support for .sha1 files
+ display information about found crcs when not calculating crc

Update (05.08.2011):
* reduce read buffe size to increase speed on optical media
+ add option disable delimiter check for CRC in filename detection
+ display ed2k and sha1 in result area

The source is now available on Github

Update (23.05.2011):
* increase UTF-8 conversion buffer (support files with unicode characters close to the path limit)
* reintroduce delimiter check for CRC in filename detection, but allow custom delimiters
* display error messages for checksum file actions
+ add reparent option to open dialog and command line switch (shell extension)
+ updated shell extension with new icons (vista+)

Update (21.11.2010):
+ SHA1 support (CRYPTOGAMS asm)
+ allow CRC32 anywhere in filename (no bracket check)
+ always send files to old instance in queue mode
+ use thread for all fileinfo and pipe operations - eliminates situations with unresponsive gui

Update (15.04.2010):
+ support for UTF-8 with BOM (reading and writing)
+ option to default to UTF-8 when opening files
+ allow [CRC_XXXXXXXX] patterns when looking for crcs
+ new MSI installers that can register the shell extension
+ x64 version

A note on the x64 version: crc calculation should have the same speed as the 32bit version, md4/ed2k calculation is a bit slower (uses win32 cryptapi instead of assembler) and md5 is a bit faster.

Update (03.11.2008):
A lot of internal changes this time, so please mail me if something broke. This was necessary to enable job queueing, now available in the settings. It requires winxp or later (since the listview group feature is only available in common controls v6). Other changes:
* RapidCRC works again on win2k (dynamic linking to uxtheme.dll)
* a fix concerning async I/O (if the system was actually performing synchronous I/O)
+ new button layout (see screenshot below)
+ new icons for the listview and buttons (the button icons require vista)
+ window position is saved on exit

Update (20.09.2008):
* switched md4 implementation from reference to emule's assembly optimized version
(reduced ed2k calculation cpu usage on my system by about 40%)

Update (15.08.2008):
* files with sizes that are an exact multiple of 1048576 caused error 38
* read errors caused incorrect hash calculation for subsequent files

Update (27.06.2008):
* one leak fixed
source updated

Update (24.06.2008):
* various small fixes
+ multithreaded calculations (one for each hash value and one doing asynchronous I/O)
source will follow soon

Update (12.05.2008):
* various small fixes
+ colum headers popup menu
+ UTF8 support (no BOM, reading and writing, see dropdown box in options)

Update (21.03.2008):
* fixed ed2k calculation for multiple files

Update (05.02.2008):
+ ED2K calculation
+ popup menu to copy the crc/md5/ed2k values or ed2k links
+ exclusion list (file extensions that should not be processed)
+ autoscroll for the listview
* various bugfixes


posted on 02/19/2012 - 12:00

The source can be found on Github


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