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image preview before uploading -IOS

I have been trying to setup up an app to allow user to capture a photo and preview on canvas before uploading. So far i have been able to capture image and place onto canvas(android chrome), but when it comes to ios using safari i am having no such luck (tried Ipad, 5C)

here is the script i have manage to piece together thanks to the help of stackoverflow community (many thanks)

The issue I am having is that when i choose selected image it should display in my iframe (as it does in chrome) when i try safari it shows no image after selecting

here is a sample link to my app SampleAPP HTML

<img src="" id="image">
<input id="input" type="file" onchange="handleFiles()">

JAVASCRIPT

<script>

function handleFiles()
{
var filesToUpload = document.getElementById('input').files;
var file = filesToUpload[0];

// 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;

    var canvas = document.createElement("canvas");


    var MAX_WIDTH = 400;
    var MAX_HEIGHT = 300;
    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);

    var dataurl = canvas.toDataURL("image/png");
    document.getElementById('image').src = dataurl;     
}
// Load files into file reader
reader.readAsDataURL(file);


// Post the data
/*
var fd = new FormData();
fd.append("name", "some_filename.jpg");
fd.append("image", dataurl);
fd.append("info", "lah_de_dah");
*/
}
</script>

You can remove using <canvas> and set existing <img> src to e.target.result : data URI of uploaded File object at FileReader() load event.

You can defined variable width , use if condition at #image load event when new src is set to check #image .naturalWidth property, if value is greater than width , set #image.width to width variable.

 <img src="" id="image"> <input id="input" type="file" onchange="handleFiles()"> <script> var img = document.getElementById("image"); var width = 400; function handleFiles() { var filesToUpload = document.getElementById('input').files; var file = filesToUpload[0]; // Create a file reader var reader = new FileReader(); // Set the image once loaded into file reader reader.onload = function(e) { img.onload = function() { if (this.naturalWidth > width) { this.width = width; } } img.src = e.target.result; } reader.readAsDataURL(file); } </script> 

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