Change createImageBitMaps's imageOrientation attributes

[yiyix]

This is step 2 in #8085 (comment). Fixes #8085.

• At least two implementers are interested (and none opposed):

  • Chrome
  • Firefox (Add createImageBitMaps's imageOrientation "none" #8085 (comment))

• Tests are written and can be reviewed and commented upon at:

  • Add tests for CreateImageBitmap with "ImageOrientation: none" web-platform-tests/wpt#38654

• Implementation bugs are filed:

  • Chromium
  • Gecko
  • WebKit

• MDN issue is filed: Add a new option "ImageOrientation: none" to CreateImageBitmap  mdn/content#24857

(See WHATWG Working Mode: Changes for more details.)

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/imagebitmap-and-animations.html ( diff )

[domenic]

Here's an initial review focused on wording stuff. Hope it's helpful!

[yiyix]

Thank you so much for the initial review!!

[aardgoose]

I assume the 'from-image' and 'none' imageOrientation options are intended to apply to ImageBitmaps created from HTMLVideo elements. If so are wpt tests for this needed?

This would clarify the following FF bug https://bugzilla.mozilla.org/show_bug.cgi?id=1593790

[yiyix]

I assume the 'from-image' and 'none' imageOrientation options are intended to apply to ImageBitmaps created from HTMLVideo elements. If so are wpt tests for this needed?

This would clarify the following FF bug https://bugzilla.mozilla.org/show_bug.cgi?id=1593790

This mainly applies to images with specified orientation in EXIF (Exchangeable image file format) metadata. One setting ignore the orientation and one setting uses the orientation. I have added tests here: web-platform-tests/wpt#38654

[aardgoose]

The reason I mention it is that chrome follows image rotation settings* in imageBitmaps created from Video elements while Firefox doesn't. They also diverge when creating WebGL textures directly from Video elements.

Not EXIF but have the same effect.

[yiyix]

The reason I mention it is that chrome follows image rotation settings* in imageBitmaps created from Video elements while Firefox doesn't. They also diverge when creating WebGL textures directly from Video elements.

Not EXIF but have the same effect.

This change of spec is supposed to clear that ambiguity. Chrome uses to use the option "none" to say no additional change follow the orientation in the metadata; where Firefox uses "none" as disregard the rotation settings.

I first introduced the new option "from-image" to describe what Chrome follows, which also matches the CSS spec.

In this change, I am hoping to repurpose the meaning of 'none'. I also submitted a bug for firefox to ask them to use the rotational setting for 'from-image' option.

[smaug----]

do we know how much this feature has been used, in other words, do we think the change is web compatible?

[zcorpan]

@smaug---- see #8085 (comment)

[aardgoose]

@yiyix
I understand the reason for the change. As you have confirmed that video should be included, wpt tests for the imageBitmap sourced from video are needed.

Incidentally I have submitted a patch to fix one of the FF imageBitmap from HTMLImage rotation bugs and have another patch ready to fix the HTMLVideo case for imageBitmaps.

[zcorpan]

As of Safari 17.2 the change from none to from-image seems to be implemented in Chromium/Gecko/WebKit. I think we should land this (but it needs a rebase).

I added a "needs tests" label in May, but I don't recall why. Tests are referenced above. Are more tests needed?