Changeset 95482 in webkit


Ignore:
Timestamp:
Sep 19, 2011 3:23:28 PM (13 years ago)
Author:
commit-queue@webkit.org
Message:

Fix nonpremultiplied webgl toDataURL to jpeg
​https://bugs.webkit.org/show_bug.cgi?id=68366

Source/WebCore:

The canvas spec says that toDataURL to formats without an alpha must
be "composited onto a solid black background using the source-over
operator." Do that.

Patch by John Bauman <​jbauman@chromium.org> on 2011-09-19
Reviewed by Kenneth Russell.

  • platform/image-encoders/skia/JPEGImageEncoder.cpp:

(WebCore::RGBAtoRGB):

LayoutTests:

Update the premultiplyalpha-test from the WebGL conformance tests.

Patch by John Bauman <​jbauman@chromium.org> on 2011-09-19
Reviewed by Kenneth Russell.

  • fast/canvas/webgl/premultiplyalpha-test-expected.txt:
  • fast/canvas/webgl/premultiplyalpha-test.html:
Location:
trunk
Files:
5 edited

Legend:

Unmodified
Added
Removed

  • trunk/LayoutTests/ChangeLog

    r95478 r95482  
     12011-09-19  John Bauman  <jbauman@chromium.org>
     2
     3        Fix nonpremultiplied webgl toDataURL to jpeg
     4        https://bugs.webkit.org/show_bug.cgi?id=68366
     5
     6        Update the premultiplyalpha-test from the WebGL conformance tests.
     7
     8        Reviewed by Kenneth Russell.
     9
     10        * fast/canvas/webgl/premultiplyalpha-test-expected.txt:
     11        * fast/canvas/webgl/premultiplyalpha-test.html:
     12
    1132011-09-19  Ryosuke Niwa  <rniwa@webkit.org>
    214

  • trunk/LayoutTests/fast/canvas/webgl/premultiplyalpha-test-expected.txt

    r81213 r95482  
    44
    55
    6 testing: premultipliedAlpha: true toDataURL: true
     6testing: premultipliedAlpha: true imageFormat: image/png
    77PASS gl.getContextAttributes().premultipledAlpha is premultipledAlpha
     8PASS gl.getContextAttributes().preserveDrawingBuffer is true
    89PASS getError was expected value: NO_ERROR : Should be no errors from setup.
    910PASS getError was expected value: NO_ERROR : Should be no errors from drawing.
    … …  
    1213PASS should draw with 64,128,255,128
    1314
    14 testing: premultipliedAlpha: true toDataURL: false
     15testing: premultipliedAlpha: true imageFormat: undefined
    1516PASS gl.getContextAttributes().premultipledAlpha is premultipledAlpha
     17PASS gl.getContextAttributes().preserveDrawingBuffer is true
    1618PASS getError was expected value: NO_ERROR : Should be no errors from setup.
    1719PASS getError was expected value: NO_ERROR : Should be no errors from drawing.
    … …  
    2022PASS should draw with 64,128,255,128
    2123
    22 testing: premultipliedAlpha: false toDataURL: true
     24testing: premultipliedAlpha: false imageFormat: image/png
    2325PASS gl.getContextAttributes().premultipledAlpha is premultipledAlpha
     26PASS gl.getContextAttributes().preserveDrawingBuffer is true
    2427PASS getError was expected value: NO_ERROR : Should be no errors from setup.
    2528PASS getError was expected value: NO_ERROR : Should be no errors from drawing.
    … …  
    2831PASS should draw with 255,192,128,1
    2932
    30 testing: premultipliedAlpha: false toDataURL: false
     33testing: premultipliedAlpha: false imageFormat: undefined
    3134PASS gl.getContextAttributes().premultipledAlpha is premultipledAlpha
     35PASS gl.getContextAttributes().preserveDrawingBuffer is true
    3236PASS getError was expected value: NO_ERROR : Should be no errors from setup.
    3337PASS getError was expected value: NO_ERROR : Should be no errors from drawing.
    … …  
    3640PASS should draw with 255,192,128,1
    3741
     42testing: premultipliedAlpha: false imageFormat: image/jpeg
     43PASS gl.getContextAttributes().premultipledAlpha is premultipledAlpha
     44PASS gl.getContextAttributes().preserveDrawingBuffer is true
     45PASS getError was expected value: NO_ERROR : Should be no errors from setup.
     46PASS getError was expected value: NO_ERROR : Should be no errors from drawing.
     47PASS getError was expected value: NO_ERROR : Should be no errors from creating copy.
     48PASS getError was expected value: NO_ERROR : Should be no errors from 2nd drawing.
     49PASS should draw with 128,128,128,255
     50
     51testing: premultipliedAlpha: true imageFormat: image/jpeg
     52PASS gl.getContextAttributes().premultipledAlpha is premultipledAlpha
     53PASS gl.getContextAttributes().preserveDrawingBuffer is true
     54PASS getError was expected value: NO_ERROR : Should be no errors from setup.
     55PASS getError was expected value: NO_ERROR : Should be no errors from drawing.
     56PASS getError was expected value: NO_ERROR : Should be no errors from creating copy.
     57PASS getError was expected value: NO_ERROR : Should be no errors from 2nd drawing.
     58PASS should draw with 128,128,128,255
     59

  • trunk/LayoutTests/fast/canvas/webgl/premultiplyalpha-test.html

    r81213 r95482  
    1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
    2   "http://www.w3.org/TR/html4/loose.dtd">
     1<!DOCTYPE html>
    32<html>
    43<head>
     4<meta charset="utf-8">
    55<title>Test the WebGL premultipledAlpha context creation flag.</title>
    66<link rel="stylesheet" href="../../js/resources/js-test-style.css"/>
    … …  
    2222    expectedColor: [64, 128, 255, 128],
    2323    errorRange: 2,
    24     useToDataURL: true,
     24    imageFormat: "image/png"
    2525  },
    2626  // If premultipledAlpha is true then
    … …  
    3131    expectedColor: [64, 128, 255, 128],
    3232    errorRange: 2,
    33     useToDataURL: false,
    3433  },
    3534  // If premultipledAlpha is false then
    … …  
    4039    expectedColor: [255, 192, 128, 1],
    4140    errorRange: 0,
    42     useToDataURL: true,
     41    imageFormat: "image/png"
    4342  },
    4443  // If premultipledAlpha is false then
    … …  
    4948    expectedColor: [255, 192, 128, 1],
    5049    errorRange: 0,
    51     useToDataURL: false,
     50  },
     51  // If premultipledAlpha is false then
     52  // [texture]             [canvas]            [dataURL]
     53  // 255, 255, 255, 128 -> 255, 255, 255, 128 -> 128, 128, 128, 255
     54  { creationAttributes: {premultipliedAlpha: false},
     55    sentColor: [255, 255, 255, 128],
     56    expectedColor: [128, 128, 128, 255],
     57    errorRange: 2,
     58    imageFormat: "image/jpeg"
     59  },
     60  // If premultipledAlpha is true then
     61  // [texture]             [canvas]            [dataURL]
     62  // 128, 128, 128, 128 -> 255, 255, 255, 128 -> 128, 128, 128, 255
     63  { creationAttributes: {},
     64    sentColor: [128, 128, 128, 128],
     65    expectedColor: [128, 128, 128, 255],
     66    errorRange: 2,
     67    imageFormat: "image/jpeg"
    5268  }
    5369];
    … …  
    6985     var test = tests[g_count++];
    7086     canvas = document.createElement("canvas");
     87     // Need to preserve drawing buffer to load it in a callback
     88     test.creationAttributes.preserveDrawingBuffer = true;
    7189     gl = wtu.create3DContext(canvas, test.creationAttributes);
    7290     var premultipliedAlpha = test.creationAttributes.premultipliedAlpha != false;
    7391     debug("")
    74      debug("testing: premultipliedAlpha: " + premultipliedAlpha + " toDataURL: " + test.useToDataURL);
     92     debug("testing: premultipliedAlpha: " + premultipliedAlpha + " imageFormat: " + test.imageFormat);
    7593
    7694     shouldBe('gl.getContextAttributes().premultipledAlpha', 'premultipledAlpha');
     95     shouldBeTrue('gl.getContextAttributes().preserveDrawingBuffer');
    7796
    7897     var program = wtu.setupTexturedQuad(gl);
    … …  
    97116       gl.pixelStorei(gl.UNPACK_COLORSPACE_CONVERSION_WEBGL, false);
    98117       gl.bindTexture(gl.TEXTURE_2D, pngTex);
    99        if (test.useToDataURL) {
     118       if (test.imageFormat) {
    100119          // create texture from image
    101120          gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, this);
    … …  
    118137     }
    119138
    120      if (test.useToDataURL) {
     139     if (test.imageFormat) {
    121140        // Load canvas into string using toDataURL
    122         var png = canvas.toDataURL();
    123         // Load string into the texture
    124         var input = document.createElement("img");
    125         input.onload = loadTexture;
    126         input.src = png;
     141        var imageUrl = canvas.toDataURL(test.imageFormat);
     142        if (test.imageFormat != "image/png" &&
     143            (imageUrl.indexOf("data:image/png,") == 0 ||
     144             imageUrl.indexOf("data:image/png;") == 0)) {
     145          debug("Image format " + test.imageFormat + " not supported; skipping");
     146          setTimeout(doNextTest, 0);
     147        } else {
     148          // Load string into the texture
     149          var input = document.createElement("img");
     150          input.onload = loadTexture;
     151          input.src = imageUrl;
     152        }
    127153     } else {
    128154        // Load canvas into the texture asynchronously (to prevent unbounded stack consumption)
    … …  
    139165</script>
    140166
    141 <script>
    142 </script>
    143 
    144167</body>
    145168</html>

  • trunk/Source/WebCore/ChangeLog

    r95479 r95482  
     12011-09-19  John Bauman  <jbauman@chromium.org>
     2
     3        Fix nonpremultiplied webgl toDataURL to jpeg
     4        https://bugs.webkit.org/show_bug.cgi?id=68366
     5
     6        The canvas spec says that toDataURL to formats without an alpha must
     7        be "composited onto a solid black background using the source-over
     8        operator." Do that.
     9
     10        Reviewed by Kenneth Russell.
     11
     12        * platform/image-encoders/skia/JPEGImageEncoder.cpp:
     13        (WebCore::RGBAtoRGB):
     14
    1152011-09-19  Chris Marrin  <cmarrin@apple.com>
    216

  • trunk/Source/WebCore/platform/image-encoders/skia/JPEGImageEncoder.cpp

    r94591 r95482  
    9393{
    9494    for (; pixelCount-- > 0; pixels += 4) {
    95         *output++ = pixels[0];
    96         *output++ = pixels[1];
    97         *output++ = pixels[2];
     95        // Do source-over composition on black.
     96        *output++ = pixels[0] * pixels[3] / 255;
     97        *output++ = pixels[1] * pixels[3] / 255;
     98        *output++ = pixels[2] * pixels[3] / 255;
    9899    }
    99100}
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