MK Normalize

For many tasks involving audio (e.g. compressing WAV files to MP3), it's nice to have a utility which can normalize audio files. The purpose of this is to make all audio files sound equally loud. I used to use CoolEdit (from Syntrillium) to do this task, but since this audio editor is capable of doing much more than just normalizing waves, it's a bit slow for this task. Besides, it cannot be easily called from a batch file.

So I looked for a better alternative, but found none. That was when I decided to write my own normalizer. It's a small Win32 console mode application called normalize. It can handle 8-bit and 16-bit PCM WAV files of up to 4 GBs (larger WAV files are not possible anyway), and it is fast. Hell, faster than your disk I/O anyway.

Sometimes WAV files have peak samples that occur so rarely or in non-critical passages that it can be afforded to clip them without introducing audible artifacts. If these are not clipped, they prevent normalizing the whole file to "normal" levels (as by default normalize does not clip any sample at all).

To help combat this problem, Lapo Luchini contributed some code which internally produces a full statistic of the sample values and only considers peak values that have a given percentile in the statistic. It's called "smartpeak" (-s option); start with a percentile of 99.99% and decrease if necessary.

The MK Normalize application was designed to be a small and fast command line PCM WAV normalizer.