use ladspa plugin pitchScale for playing double speed

[haggai.eran@…]

When you use [ and ] to change the speed of a movie it plays the audio in a
different pitch (obviously). It would be really cool if mplayer used the
pitchScale plugin to modify the audio pitch to be compatible with the playing speed.

[pivanov@…]

I used a Charlie Brej's patch I found on the mailing list to get the desired effect:

​http://lists.mplayerhq.hu/pipermail/mplayer-dev-eng/2007-May/052001.html

There was an earlier version that used the kiss_fft that was less echo-y, though some of the kiss_fft files were missing from the patch (you can get those on sourceforge)

​http://lists.mplayerhq.hu/pipermail/mplayer-dev-eng/2007-May/051972.html

This patch does not deal with dynamic changes - you specify the pitch scaling from the command line like this: mplayer movie.avi -af pitch=1.5 -speed 1.5

[compn]

-speed 1.5 -af scaletempo is the correct way to do it now.