-
-
Save carlosmcevilly/3865987 to your computer and use it in GitHub Desktop.
Photo capture, manipulation, and upload in iOS6 Safari
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
<!DOCTYPE html> | |
<html> | |
<head> | |
<title>iOS6 Safari Photo Capture Demo</title> | |
<script type="text/javascript"> | |
window.onload = function() { | |
var input = document.getElementById("input"); | |
input.addEventListener("change", handleFile); | |
} | |
function handleFile(e) { | |
var canvas = document.getElementById('canvas'); | |
var ctx = canvas.getContext("2d"); | |
var reader = new FileReader; | |
reader.onload = function (event) { | |
var img = new Image(); | |
img.src = reader.result; | |
img.onload = function () { | |
canvas.width = img.width/3; | |
canvas.height = img.height/3; | |
ctx.drawImage(this, 0, 0, canvas.width, canvas.height); | |
// Do whatever image operation you need (resize/crop, visual effects, barcode detection, etc.+ | |
invertImage(ctx, canvas); | |
// You can even upload the new image to your server | |
// postCanvasDataToServer(canvas); | |
} | |
} | |
reader.readAsDataURL(e.target.files[0]); | |
} | |
// Just an example of the pixel-by-pixel manipulations you could make on the client side | |
function invertImage(ctx, canvas) { | |
var imageData = ctx.getImageData(0, 0, canvas.width, canvas.height); | |
var data = imageData.data; | |
for (var i = 0; i < data.length; i += 4) { | |
data[i] = 255 - data[i]; // red | |
data[i + 1] = 255 - data[i + 1]; // green | |
data[i + 2] = 255 - data[i + 2]; // blue | |
// i+3 is alpha | |
} | |
ctx.putImageData(imageData, 0, 0); | |
} | |
// An example of how you would post the image on the canvas to a server | |
function postCanvasDataToServer(canvas) { | |
var finalFile = canvas.toDataURL("image/png"); | |
var postData = 'canvasData=' + finalFile; | |
var ajax = new XMLHttpRequest(); | |
ajax.open('POST', 'upload_image', true); | |
ajax.setRequestHeader('Content-Type', 'canvas/upload'); | |
ajax.onreadystatechange = function () { | |
if (ajax.readyState == 4) { | |
alert('posted'); | |
} | |
} | |
ajax.send(postData); | |
} | |
</script> | |
</head> | |
<body> | |
<h1>iOS6 Safari Photo Capture Demo</h1> | |
<input type="file" id="input" name="input" accept="image/*"></input> | |
<canvas id="canvas"></canvas> | |
</body> | |
</html> |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment