Script for export from eps to jpg done. Just need to know jpg pixel dimensions?

Question

i have a script which export eps to jpg using below script (width is always 1276 px). Is there any way to know the dimension of the each jpg files as an alert?
#target illustrator
var i,  files, sourceDoc, targetFile;
files = File.openDialog ("Hi, Please select EPS file(s)", /.eps$/, true);
try
if (files.length > 0)
  for ( i = 0; i < files.length; i++ )
        sourceDoc = app.open(files[i]);
        var myVisibleBounds = sourceDoc.visibleBounds;
        myVisibleBounds[0] = myVisibleBounds[0] - 1;  // left
        myVisibleBounds[1] = myVisibleBounds[1] + 0.5;   // top
        myVisibleBounds[2] = myVisibleBounds[2] + 1;   // right
        myVisibleBounds[3] = myVisibleBounds[3] - 1 ;    // bottom
        sourceDoc.artboards[0].artboardRect = myVisibleBounds;
//        var docLeft = sourceDoc.artboards[0].artboardRect[0] - 50;
//        var docTop = sourceDoc.artboards[0].artboardRect[1] + 50;
//        var docRight = sourceDoc.artboards[0].artboardRect[2] + 50 ;
//        var docBottom = sourceDoc.artboards[0].artboardRect[3] -50 ;
        var sourceDocWidth = Math.round(myVisibleBounds[2] - myVisibleBounds[0]);
//        var sourceDocHeight = docTop - docBottom;
        var myZoom = (1276/sourceDocWidth) * 100;
//        alert(sourceDocWidth + " Math round: " + Math.round(sourceDocWidth) + "   " + myZoom);
        targetFile = getNewName();
   // Call function getPDFOptions get the PDFSaveOptions for the files
        exportOptions = exportJPEG( );
   // Save as pdf
   sourceDoc.exportFile (targetFile, ExportType.JPEG, exportOptions);
   sourceDoc.close(SaveOptions.DONOTSAVECHANGES);
  alert( "Done" );
catch(e)
    alert(e +  "\r" + "No files selected");
function getNewName()
var ext, docName, newName, saveInFile, docName;
docName = sourceDoc.name;
//ext = '.pdf'; // new extension for pdf file
newName = "";
for ( var i = 0 ; docName[i] != "." ; i++ )
        newName = newName + docName[i];
newName = newName;
saveInFile = new File(sourceDoc.path + '/' + newName );
    return saveInFile;
function exportJPEG()
    var exportOptions = new ExportOptionsJPEG();
    exportOptions.artBoardClipping = true;
    exportOptions.antiAliasing = false;
    exportOptions.qualitySetting = 100;
    exportOptions.horizontalScale = myZoom;
    exportOptions.verticalScale   = myZoom;
//    exportOptions.transparency = false;
//exportOptions.saveAsHTML = true;
    return exportOptions;

Answer 1

Does this help?
I do applescript and javascript is another language but I found this by searching google:
var img = document.getElementById('imageId');
var width = img.clientWidth;
var height = img.clientHeight;
From:
Determining image file size + dimensions via Javascript? - Stack Overflow