Encode html img to base64

by awolf2904

HTML

<div>
    <!-- used base64 encoded image because of security error with cross-origin image directly from http://placehold.it/300x300 -->
    
    <img src="data:image/png;base64,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" id="sourceImg"/>
    <div id="output">
        <h2>test ouput of base64 encoded image:</h2>
    </div>
</div>

CSS

#output {
    display: block;
    width: 100%;
    height: 500px;
}

JavaScript

$(function() {
    var $sourceImg = $('#sourceImg');
    var $canvas = $('<canvas/>');
    var $out = $('#output');
    
    $canvas.prop({"width": $out.width(), "height": $out.height()});
    
    var ctx=$canvas.get(0).getContext("2d");
    //console.log($sourceImg.prop('src'));
    // draw image on canvas
    var img = new Image(300,300);
    img.src = $sourceImg.prop('src');
    ctx.drawImage(img,0,0);
    
    // convert canvas to base64 image
    var base64img = $canvas.get(0).toDataURL();
    //console.log(base64img);
    
    // test if encoding is correct
    var img = new Image();
    img.src = base64img;
       
    $("#output").append(img);
});