Software Diagnostics Library

An alternative to converting memory dumps to sound files is to save a memory range to a binary file and then convert it to a wave file. The latter is better for complete memory dumps which can be several Gb in size.

To save a memory range to a file use WinDbg .writemem command:

.writemem d2w-range.bin 00400000 00433000

or

.writemem d2w-range.bin 00400000 L200

I wrote a WinDbg script that saves a specified memory range and then calls a shell script which automatically converts saved binary file to a wave file and then runs whatever sound program is registered for .wav extension. On many systems it is Microsoft Media Player unless you installed any other third-party player.

The WinDbg script code (memsounds.txt):

.writemem d2w-range.bin ${$arg1} ${$arg2}
.if (${/d:$arg5})
{
  .shell -i- memsounds.cmd d2w-range ${$arg3} ${$arg4} ${$arg5}
}
.elsif (${/d:$arg4})
{
  .shell -i- memsounds.cmd d2w-range ${$arg3} ${$arg4}
}
.elsif (${/d:$arg3})
{
  .shell -i- memsounds.cmd d2w-range ${$arg3}
}
.else
{
  .shell -i- memsounds.cmd d2w-range
}

The shell script (memsounds.cmd):

dump2wave %1.bin %1.wav %2 %3 %4
%1.wav

Because WinDbg installation folder is assumed to be the default directory for both scripts and Dump2Wave.exe they should be copied to the same folder where windbg.exe is located. On my system it is

C:\Program Files\Debugging Tools for Windows

Both scripts are included in Dump2Wave package available for free download:

Dump2Wave package

To call the script from WinDbg use the following command:

$$>a< memsounds.txt Range [Freq] [Bits] [Channels]

where Range can be in Address1 Address2 or Address Lxxx format, Freq can be 44100, 22050, 11025 or 8000, Bits can be 8 or 16, Channels can be 1 or 2. By default it is 44100, 16, 2.

If you have a live debugging session or loaded a crash dump you can listen to a memory range immediately. For example, the range of memory from 00400000 to 00433000 interpreted as 44.1KHz 16bit stereo:

0:000> $$>a< memsounds.txt 00400000 00433000
Writing 33001 bytes...

C:\Program Files\Debugging Tools for Windows>dump2wave d2w-range.bin d2w-range.wav

Dump2Wave version 1.2.1
Written by Dmitry Vostokov, 2006

d2w-range.wav
d2w-range.bin
        1 file(s) copied.

C:\Program Files\Debugging Tools for Windows>d2w-range.wav
.shell: Process exited
0:000>

or the same range interpreted as 8KHz 8bit mono:

0:000> $$>a< memsounds.txt 00400000 00433000 8000 8 1
Writing 33001 bytes...

C:\Program Files\Debugging Tools for Windows>dump2wave d2w-range.bin d2w-range.wav 8000 8 1

Dump2Wave version 1.2.1
Written by Dmitry Vostokov, 2006

d2w-range.wav
d2w-range.bin
        1 file(s) copied.

C:\Program Files\Debugging Tools for Windows>d2w-range.wav
.shell: Process exited
0:000>

The script starts Windows Media Player on my system and I only need to push the play button to start listening.

Enjoy

- Dmitry Vostokov @ DumpAnalysis.org -

This entry was posted on Sunday, July 29th, 2007 at 7:07 pm and is filed under Crash Dump Analysis, Debugging, Memory Auralization, Memory Visualization, Tools, WinDbg Scripts, WinDbg Tips and Tricks. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.