normalizing audio volume for batch encoding

[MIKEMAN]

i have about 50 saturday night live clips i want to put on dvd but some have higher volume than others. how can i encode these vids and noralize the audio and batch encode (way too many clips to normalize individually
thx!

[mats.hogberg]

Basically, any normalizer works with WAV audio, the exception (AFAIK) being MP3Gain, which works with MP3 without decompressing to WAV first. So, depending on your source files, you do have to extract the audio. If it's MP3 audio, you can use MP3gain on those, for all other formats, you have to decode to wav, the normalize.
Look for some CLI apps to perform the needed steps, write a .BAT script for them to automate the process.
What to look for, depends on in what format your source files are, but the steps (worst case) are:

• Extract audio
  Decode to WAV
  Normalize
  Encode to ???
  Multiplex back with video

/Mats