textwatermark.js

    function checkCompatibility() {
    	var isOpera = !!window.opera || navigator.userAgent.indexOf(' OPR/') >= 0;
		    // Opera 8.0+ (UA detection to detect Blink/v8-powered Opera)
		var isFirefox = typeof InstallTrigger !== 'undefined';   // Firefox 1.0+
		var isSafari = Object.prototype.toString.call(window.HTMLElement).indexOf('Constructor') > 0;
		    // At least Safari 3+: "[object HTMLElementConstructor]"
		var isChrome = !!window.chrome && !isOpera;              // Chrome 1+
		var isIE = /*@cc_on!@*/false || !!document.documentMode;   // At least IE6
		return (isChrome || isFirefox) && !isIE && !isSafari;
    }



var fileIndex=0;
var allFiles = 0;


      function doUpload() {
      	fileIndex=0;
  			allFiles = document.getElementById('fileToUpload').files.length;
  
  			doUploadW(fileIndex);
  			sessionStorage.setItem("phName",document.getElementById("phName").value);
      }

      function doUploadW(fileID) {
        var file = document.getElementById('fileToUpload').files[fileID];
        var dataUrl = "";
        var fileName = file.name;

        document.getElementById('downloadImage').download =  fileName.split(".")[0] + "_watermarked." + fileName.split(".")[1];
        // Create an image
        var img = document.createElement("img");
        // Create a file reader
        var reader = new FileReader();
        // Set the image once loaded into file reader
        reader.onload = function(e)
        {
            img.src = e.target.result;
    		img.onload = function() {
		            var canvas = document.createElement("canvas");
		            // Set Width and Height
		            var MAX_WIDTH = 1500;
		            var MAX_HEIGHT =1125;
		          
		            var width = img.width;
		            var height = img.height;
		    
		            if (width > height) {
		              if (width > MAX_WIDTH) {
		                height *= MAX_WIDTH / width;
		                width = MAX_WIDTH;
		              }
		            } else {
		              if (height > MAX_HEIGHT) {
		                width *= MAX_HEIGHT / height;
		                height = MAX_HEIGHT;
		              }
		            }
		            canvas.width = width;
		            canvas.height = height;
		            var ctx = canvas.getContext("2d");
		           ctx.drawImage(img, 0, 0, width, height);
		            		    
		            
		    	ctx.fillStyle = "rgba(255, 255, 255, 1)";

		      ctx.font = "20pt Helvetica";
		      var waterMarkText = "Ph. " +  document.getElementById("phName").value + " - #IJF16";
          ctx.fillText(waterMarkText, width - (waterMarkText.length * 15), height - 20);

		            dataUrl = canvas.toDataURL("image/jpeg");
		            document.getElementById('image_preview').src = dataUrl;  
		            document.getElementById('downloadImage').href = dataUrl; 
		            document.getElementById('downloadImage').click();

				if (fileIndex < allFiles-1) {
					fileIndex ++;
					doUploadW(fileIndex);
				} else {
					location.reload();
				}
		      
	
		  }    
            
        }
        // Load files into file reader
        reader.readAsDataURL(file);
      }