var playing_on = new Image();
playing_on.src = "images/playing.gif";
var playing_off = new Image();
playing_off.src = "images/blinking.gif";

var midi_index = 1
var midi_qty = 12
var midi_song = "midi/song" + midi_index + ".htm"

function stopmidi(){
speaker.location.href = "midi/midioff.htm";
document.images.playing_bar.src = playing_off.src;
}

function backmidi() {
if (midi_index > 1 )
{
midi_index = midi_index - 1;
}
playmidi();
}

function nextmidi() {
if (midi_index < midi_qty)
{
midi_index = midi_index + 1;
}
playmidi();
}

function playmidi(){
midi_song = "midi/song" + midi_index + ".htm";  
speaker.location.href = midi_song ;
document.images.playing_bar.src = playing_on.src;
}