1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
|
<!DOCTYPE HTML>
<title>Canvas test: toDataURL parameters (Bug 564388)</title>
<script src="/tests/SimpleTest/SimpleTest.js"></script>
<link rel="stylesheet" href="/tests/SimpleTest/test.css">
<body>
<p>
This test covers the JPEG and webp quality parameter. If (when) the HTML5 spec changes the
allowed parameters for ToDataURL, new tests should go here.
</p>
<canvas id="c" width="100" height="100"><p class="fallback">FAIL (fallback content)</p></canvas>
<script>
let canvas = document.getElementById('c');
let ctx = canvas.getContext("2d");
ctx.strokeStyle = '#FF0000';
ctx.fillStyle = '#00FF00';
ctx.fillRect(0, 0, 100, 100);
ctx.beginPath();
ctx.moveTo(10, 10);
ctx.lineTo(90, 90);
ctx.stroke();
let pngData = canvas.toDataURL('image/png');
let pngQuality = canvas.toDataURL('image/png', 0.1);
is(pngQuality, pngData, "Quality is not supported for PNG images");
function checkType(imagetype) {
let imageTypeString = 'image/' + imagetype;
let imageTypeUpperString = 'IMAGE/' + imagetype.toUpperCase();
let data = canvas.toDataURL(imageTypeString);
if (data.match(new RegExp('^data:image\/' + imagetype + '[;,]'))) {
// Test the JPEG/wepb quality parameter
let fullQuality = canvas.toDataURL(imageTypeString, 1.0);
let lowQuality = canvas.toDataURL(imageTypeString, 0.1);
isnot(lowQuality, fullQuality, "A low quality (0.1) should differ from high quality (1.0) " + imageTypeString);
let medQuality = canvas.toDataURL(imageTypeString, 0.5);
isnot(medQuality, fullQuality, "A medium quality (0.5) should differ from high (1.0) " + imageTypeString);
isnot(medQuality, lowQuality, "A medium quality (0.5) should differ from low (0.5) " + imageTypeString);
let tooHigh = canvas.toDataURL(imageTypeString, 2.0);
is(tooHigh, data, "Quality above 1.0 is treated as unspecified " + imageTypeString);
let tooLow = canvas.toDataURL(imageTypeString, -1.0);
is(tooLow, data, "Quality below 0.0 is treated as unspecified " + imageTypeString);
let lowQualityExtra = canvas.toDataURL(imageTypeString, 0.1, 'foo', 'bar', null);
is(lowQualityExtra, lowQuality, "Quality applies even if extra arguments are present " + imageTypeString);
let lowQualityUppercase = canvas.toDataURL(imageTypeUpperString, 0.1);
is(lowQualityUppercase, lowQuality, "Quality applies to " + imageTypeString + " regardless of case");
let lowQualityString = canvas.toDataURL(imageTypeString, '0.1');
isnot(lowQualityString, lowQuality, "Quality must be a number (should not be a string) " + imageTypeString);
} else {
ok(false, "should get a data url " + imageTypeString);
}
}
checkType('jpeg');
checkType('webp');
</script>
|