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Comment by anonymfus | Hacker News Reader

>I’ve found the results strange in Safari and Chrome, since there’s this CSS property for <img />, image-orientation, and with it one can say to use the EXIF declared on the photo metadata to fix the orientation. The default value is 0deg. If you want show the image with the correct orientation, the value must be from-image.

I went to the linked specification (https://www.w3.org/TR/css3-images/#image-orientation) and "from-image" is not specified here as a possible value of "image-orientation".

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It seems that Firefox from-image is nonstandard (from-image in specification is only defined for image-resolution). And default behavior of ignoring EXIF rotation seems correct according to this weird specification:

>Note that some devices will "tag" an image with some metadata indicating its correct orientation, so image viewing software can do the necessary transformation themselves. Due to legacy compatibility restraints, Web browsers are required to ignore this data by default. A future level of this specification is expected to have a value that applies the metadata-specified transformation automatically.

IMO EXIF rotation should be applied always, and any CSS rotations should combine with it, not override.

> IMO EXIF rotation should be applied always, and any CSS rotations should combine with it, not override.

I agree. EXIF rotation is a part of the image and it's just an implementation detail of the image data. Browsers shouldn't leak this.

Presumably the issue is "Given that browsers that ignore EXIF rotation already exist, should modern browsers display the same page differently?"

Yes because it will fix more pages than it will break.

But what about the compatibility, graceful degradation, etc. of the browsers that yet don't support this feature? Won't that break everything else?

https://drafts.csswg.org/css-images-3/#propdef-image-orienta...

But it has been dropped from the next version which states:

> If the image has an orientation specified in its metadata, such as EXIF, the UA must rotate or flip the image to correctly orient it as the metadata specifies.

That statement appears to only apply to images created with the CSS image() function, not HTML <img>s.

It was in CSS 4 at some point:

https://www.w3.org/TR/2012/WD-css4-images-20120911/#the-imag...

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