The free
Audacity will do the trick. There's many ways to edit the running time with it, all of which may not give the desired result:
- The best way is to fade the tune down without actually altering anything, just cutting a piece off
- Cross fading to another tune may also be desirable, lowering the volume of a tune while increasing that of another. The new tune doesn't have to start from the beginning if, say, a refrain would do the job for a certain picture.
- Changing the speed of a tune. Speeding will cause chipmunk voices which may sound unintentionally funny and unsuitable for a more serious picture. Similarly, decreasing speed will make Doris Day a bass singer.
- It's also possible to change the tempo without altering the pitch. These last two should be used very cautiously, only to fix single percents of length.
One hint: Instead of saving, the result has to be Exported to an Mp3 file.
One side note: I just experimented with a song by first transposing it five semitones down and then increasing the speed about 35%. It restored the original pitch but the pace was breathtaking! Of course it got shorter, too. Only recommended for some single percents if needed.
Actually her video editing program might be able to cut the music, maybe even do the fading in and out.
