1904471 - Properly convert color space for display-p3

Status: RESOLVED FIXED

(Core :: Audio/Video: Web Codecs, task, P3)

Description

[C.M.Chang[:chunmin] | PTO]

Investigate how to properly convert color for display-p3 in videoFrame-copyTo-rgb.any.js. The R, G, B ,A values converted in Gecko implemented in bug 1902115 is different from the values in Chrome. The conversion can probably be implemented via skia's APIs.

This is a visual test page that can help to compare the values between Firefox and Chrome. The online demo is here, which might be updated from times to times.

---

update: Here is an example of the conversion. I'll try this and submit the patch if it works.

void ConvertSRGBBufferToDisplayP3(uint8_t* srcBuffer, int width, int height, uint8_t* dstBuffer) {
    auto srcColorSpace = SkColorSpace::MakeSRGB();
    SkImageInfo srcInfo = SkImageInfo::Make(width, height, kRGBA_8888_SkColorType, kUnpremul_SkAlphaType, srcColorSpace);

    SkBitmap srcBitmap;
    srcBitmap.installPixels(srcInfo, srcBuffer, width * 4);

    auto dstColorSpace = SkColorSpace::MakeRGB(SkNamedTransferFn::kSRGB, SkNamedGamut::kDisplayP3);

    SkBitmap dstBitmap;
    dstBitmap.allocPixels(srcInfo.makeColorSpace(dstColorSpace));

    srcBitmap.readPixels(dstBitmap.pixmap());

    memcpy(dstBuffer, dstBitmap.getPixels(), width * height * 4);
}

Comment 1

[C.M.Chang[:chunmin] | PTO]

Attachment: Bug 1904471 - Convert SRGB data to Display-P3 if needed

Comment 2

[C.M.Chang[:chunmin] | PTO]

Attachment: Bug 1904471 - Implement ConvertSRGBBufferToDisplayP3

Depends on D215225

Comment 3

[C.M.Chang[:chunmin] | PTO]

Attachment: Bug 1904471 - Update WPT expectations

The display-p3 color comparision failures are due to bug 1770258.
Currently, canvas's getImageData is unable to provide data in required
color space.

Depends on D215226

Comment 4

[C.M.Chang[:chunmin] | PTO]

Attachment: videoFrame-copyTo-rgb.html

visual test page

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/ce2a296e14f2
Convert SRGB data to Display-P3 if needed r=media-playback-reviewers,padenot
https://hg.mozilla.org/integration/autoland/rev/4f35ae92d26a
Implement ConvertSRGBBufferToDisplayP3 r=media-playback-reviewers,padenot
https://hg.mozilla.org/integration/autoland/rev/26bd15d06477
Update WPT expectations r=media-playback-reviewers,padenot

Comment 6

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/ce2a296e14f2
https://hg.mozilla.org/mozilla-central/rev/4f35ae92d26a
https://hg.mozilla.org/mozilla-central/rev/26bd15d06477