暂停，增加＆amp;减少间隔

Question

我目前正在编写一个代码来创建幻灯片。我的暂停按钮工作一次，但一旦它再次开始播放，然后再次暂停。 ＆安培;一旦按下增加按钮，同样的事情。减少按钮不起作用。我尝试了什么。有人可以指出我正确的方向或让我知道什么是错的。 http://jsfiddle.net/#&togetherjs=7F7KQf0TtS

var pic= new Array();
var pcount= 0; 
var pindex = 0;
var ptimer;

var cap= new Array();
var ccount= 0; 
var cindex = 0;
var ctimer;


var resetButton = document.getElementbyId('resetButton');
resetButton.onclick= reloadPage;

function getallpics(){
    var size = prompt("How many pictures are you uploading?");
    for (var i = 0; i<size; i++) {
        pic[i] = prompt("Enter picture filename:");
        pindex++;
        cap[i] = prompt("Enter caption:");
        cindex++;
    }
}

function getpics() {
        pcount++;
        if (pcount > pindex) {
            pcount = 1;
        }
        document.getElementById("pictures").innerHTML= "<img src=" +pic[pcount-1]+ ">";
}

function getcaps(){
    ccount++;
    if(ccount > cindex){
        ccount=1;
    }
    document.getElementById("captions").innerHTML = cap[ccount-1];
}

function displaypics() {
    ptimer = setInterval("getpics()", 3000);
    ctimer = setInterval("getcaps()", 3000);
}

function pause(){
    clearTimeout(ptimer);
    clearTimeout(ctimer);
}

function increase() {
   ptimer = setInterval("getpics()", 1000);
   ctimer = setInterval("getcaps()", 1000);
}


function decrease() {
   ptimer = setInterval("getpics()", 6000);
   ctimer = setInterval("getcaps()", 6000);
}

function reloadPage(){
   window.location.reload();
}