This tool is use to is used to manipulate the audio on laserdisc CHD images to synchronize the audio. The details below come straight from the Mame documentation. To be honest, 99.9% of Mame users will never need to use this program, but here's some details anyway.
Assists in resynchronizing audio tracks in a CHD (Compressed Hunks of Data) file with frames. The offset parameter and slope option make a linear equation f(x) which describes the sample offset from the source as a function of field.