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POHTML5 Canvas drawImage ratio bug iOS
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copied!<p>I want to resize the image taken from the iOS camera on the client side with HTML5 Canvas but I keep running in this weird bug where the image has a wrong ratio if bigger than ~1.5mb</p> <p>It works on the desktop but not in the latest iOS version with the media upload API.</p> <p>You can see an example here: <a href="http://jsbin.com/ekuros/1">http://jsbin.com/ekuros/1</a></p> <p>Any idea how to fix this please? Is this a memory issue?</p> <pre><code>$('#file').on('change', function (e) { var file = e.currentTarget.files[0]; var reader = new FileReader(); reader.onload = function (e) { var image = $('<img/>'); image.on('load', function () { var square = 320; var canvas = document.createElement('canvas'); canvas.width = square; canvas.height = square; var context = canvas.getContext('2d'); context.clearRect(0, 0, square, square); var imageWidth; var imageHeight; var offsetX = 0; var offsetY = 0; if (this.width > this.height) { imageWidth = Math.round(square * this.width / this.height); imageHeight = square; offsetX = - Math.round((imageWidth - square) / 2); } else { imageHeight = Math.round(square * this.height / this.width); imageWidth = square; offsetY = - Math.round((imageHeight - square) / 2); } context.drawImage(this, offsetX, offsetY, imageWidth, imageHeight); var data = canvas.toDataURL('image/jpeg'); var thumb = $('<img/>'); thumb.attr('src', data); $('body').append(thumb); }); image.attr('src', e.target.result); }; reader.readAsDataURL(file); }); </code></pre>

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