Export selected items on each page in InDesign to JPEG

Question

Hi All,
I have InDesign CS5.5. I have a document with more than 50 pages and each page has unique image and the description for image.
I need to export each page as JPEG. but i don't want to export full page. i need only the items on each page. So i go to each page and select all the items and export. while exporting i use the same name of the image used in each page.
I tried writing a script but it exports only the active page. i do not know how to navigate to the next page and export.
is some one can help.
below is my script.
var myDoc = app.activeDocument;
var myNumPages = myDoc.pages.length;  //get the number of pages
var myFilePath = myDoc.filePath; //get the file path
var myRectangle = app.activeWindow.activePage.allGraphics; //get the graphics of the active page
var myPageName = app.activeWindow.activePage.name; //get the page name.
           if(myRectangle.length >1)
                    alert("the page has more than one image. Delete the other image to export");
                    exit();
var myImageName = myRectangle[0].itemLink.name; //get the name of the image
app.select(NothingEnum.NOTHING);
for(var i=0; i<myNumPages; i++)
          app.jpegExportPreferences.jpegQuality = JPEGOptionsQuality.high;
          app.jpegExportPreferences.exportResolution = 300;
          app.jpegExportPreferences.jpegExportRange = ExportRangeOrAllPages.exportRange;
          app.jpegExportPreferences.pageString = myPageName;
          mySelectedItems();
function mySelectedItems()
          var myObj = new Array;
          myObj = app.activeWindow.activePage.pageItems; 
          try
                              app.activeWindow.activePage.groups.add(myObj);
                              catch(e)
          app.select(app.activeWindow.activePage.allPageItems);
          app.selection[0].exportFile(ExportFormat.JPG, File(myFilePath+"/"+myImageName+".JPEG"), false);

Answer 1

export all image of each page try like this
var myDoc = app.activeDocument;
var myFolder = myDoc.filePath;
var myImage = myDoc.allGraphics;
for (var i=0; myImage.length>i; i++){
    app.select(myImage[i]);
    var MyImageNmae  = myImage[i].itemLink.name;
    app.jpegExportPreferences.jpegQuality = JPEGOptionsQuality.high;
    app.jpegExportPreferences.exportResolution = 300;
       app.selection[0].exportFile(ExportFormat.JPG, File(myFolder+"/"+MyImageNmae+".JPEG"), false);
    alert(myImage[i].itemLink.name)