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                <div class="upload"><input type="file" name="file" id="file"></div>
<canvas id="canvas"></canvas>




                var file = document.getElementById('file');
var canvas = document.getElementById('canvas');
var canvasWidth = 400;
var canvasHeight = 300;
var uploadImgSrc;

// Canvasの準備
canvas.width = canvasWidth;
canvas.height = canvasHeight;
var ctx = canvas.getContext('2d');

function loadLocalImage(e) {
	// ファイル情報を取得
	var fileData =[0];

	// 画像ファイル以外は処理を止める
	if(!fileData.type.match('image.*')) {

	// FileReaderオブジェクトを使ってファイル読み込み
	var reader = new FileReader();
	// ファイル読み込みに成功したときの処理
	reader.onload = function() {
		// Canvas上に表示する
		uploadImgSrc = reader.result;
	// ファイル読み込みを実行

// ファイルが指定された時にloadLocalImage()を実行
file.addEventListener('change', loadLocalImage, false);

// Canvas上に画像を表示する
function canvasDraw() {
	// canvas内の要素をクリアする
	ctx.clearRect(0, 0, canvasWidth, canvasHeight);

	// Canvas上に画像を表示
	var img = new Image();
	img.src = uploadImgSrc;
	img.onload = function() {
		ctx.drawImage(img, 0, 0, canvasWidth, this.height * (canvasWidth / this.width));