ImageData中的元素反转颜色 255-data[i,i+1,i+2]
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>converse color</title>
</head>
<body>
<canvas id=‘myCanvas‘ width=‘800‘ height=‘600‘>
your browser does not support canvas
</canvas>
<script type="text/javascript">
var c = document.getElementById(‘myCanvas‘);
var ctx = c.getContext(‘2d‘);
var img = new Image();
img.src = ‘face.jpg‘;
img.onload = function() {
ctx.drawImage(img, 0, 0);
var imgData = ctx.getImageData(0, 0, 250, 250);
var pixels = imgData.data;
for (var i = 0, n = pixels.length; i < n; i += 4) {
pixels[i] = 255 - pixels[i];
pixels[i + 1] = 255 - pixels[i + 1];
pixels[i + 2] = 255 - pixels[i + 2];
}
ctx.putImageData(imgData, 250, 0);
};
</script>
</body>
</html>
时间： 2024-11-06 23:40:51