JavaScript/jQuery: EXIF convert

function getShutterSpeed(exifValue)
{
    var ShutterSpeedValues = new Array();
    var exifShutterSpeedValue;
   
    ShutterSpeedValues["1/4000"] = 1/4000;
    ShutterSpeedValues["1/3200"] = 1/3200;
    ShutterSpeedValues["1/2500"] = 1/2500;    
    ShutterSpeedValues["1/2000"] = 1/2000;
    ShutterSpeedValues["1/1600"] = 1/1600;
    ShutterSpeedValues["1/1500"] = 1/1500;
    ShutterSpeedValues["1/1250"] = 1/1250;
    ShutterSpeedValues["1/1000"] = 1/1000;
    ShutterSpeedValues["1/800"] = 1/800;
    ShutterSpeedValues["1/750"] = 1/750;
    ShutterSpeedValues["1/640"] = 1/640;
    ShutterSpeedValues["1/500"] = 1/500;
    ShutterSpeedValues["1/400"] = 1/400;
    ShutterSpeedValues["1/320"] = 1/320;
    ShutterSpeedValues["1/250"] = 1/250;
    ShutterSpeedValues["1/200"] = 1/200;
    ShutterSpeedValues["1/180"] = 1/180;
    ShutterSpeedValues["1/160"] = 1/160;
    ShutterSpeedValues["1/125"] = 1/125;
    ShutterSpeedValues["1/100"] = 1/100;
    ShutterSpeedValues["1/90"] = 1/90;
    ShutterSpeedValues["1/80"] = 1/80;
    ShutterSpeedValues["1/60"] = 1/60;
    ShutterSpeedValues["1/50"] = 1/50;
    ShutterSpeedValues["1/45"] = 1/45;
    ShutterSpeedValues["1/40"] = 1/40;    
    ShutterSpeedValues["1/30"] = 1/30;
    ShutterSpeedValues["1/25"] = 1/25;
    ShutterSpeedValues["1/20"] = 1/20;
    ShutterSpeedValues["1/15"] = 1/15;
    ShutterSpeedValues["1/13"] = 1/13;
    ShutterSpeedValues["1/10"] = 1/10;
    ShutterSpeedValues["1/8"] = 1/8;
    ShutterSpeedValues["1/6"] = 1/6;
    ShutterSpeedValues["1/5"] = 1/5;
    ShutterSpeedValues["1/4"] = 1/4;
    ShutterSpeedValues["1/3.2"] = 1/3.2;    
    ShutterSpeedValues["1/2.5"] = 1/2.5;
    ShutterSpeedValues["1/2"] = 1/2;
    ShutterSpeedValues["1.5"] = 1.5;
    ShutterSpeedValues["1/0.7"] = 1/0.7;
    /* Add new values here */
   
    for (value in ShutterSpeedValues)
    {
        if(exifValue == eval(ShutterSpeedValues[value]))
        {
            thisExifShutterSpeedValue = value;
            break;
        }
        else
        {
            thisExifShutterSpeedValue = ‘n/a [’ + exifValue + ‘]’;
        }            
    }
   
    return thisExifShutterSpeedValue;
}
 

function get_exif(image)
{
    var ApertureValue = image.exif("FNumber");
    var ExposureTime = getShutterSpeed(image.exif("ExposureTime"));
    var ISOSpeedRatings = image.exif("ISOSpeedRatings");
    var FocalLength = image.exif("FocalLength");
    var Model = image.exif("Model");
};