iPhone 11 Pro Has Broken Exif Orientation Data | Hacker News Reader

iPhone 11 Pro Has Broken Exif Orientation Data

blog.feld.me

34 pointszdw10 comments

I'm trying to understand what's broken here. The example is a 90° rotated (portrait) image, and the exif shows a 90° rotation. It's correct, isn't it?

Uncertain, but I checked some portrait images I took on my older iphone (with the back camera) and preview.app says:

orientation 6: 90 degrees CCW

Yeah this definitely isn’t new behavior. Mine has always done this on my iPhone 6s. Showing 90 degrees CCW when in portrait mode. If anything I think mine is backwards to the CW shown on the iPhone 11.

You can use the volume button as a take photo button. On mine if you hold it like a camera and do that, the picture is rotated 180. I think that would be 0 degrees on the new iPhone, which seems more correct to me.

Either way, it displays properly oriented if the software handles exif data correctly.

I think he's trying to say that the iPhone is a portrait device by default and has not been rotated to take the picture, but that's what makes the title and attitude baffling -- it's not broken exif data so much as a disagreement about what is considered the reference point; the blog author thinks the iPhone is portrait, because it's portrait, and Apple sets the reference point to be landscape, because most cameras are landscape. Big whoop?

This might matter for displays that try to compensate for the orientation data, but I'm pretty sure that's an incorrect practice.

Honestly it's only broken if the raw output of the camera and the exif rotation disagree. If the raw output is in landscape mode and the phone considered that landscape mode to be "no rotation", then there is no disagreement.

It's correct, which you can verify by looking at the the "Image Size" field, which is 4032x3024, i.e. 4:3 landscape - to achieve the portrait photo shown, this must be rotated.

Author is holding it wrong.

I think he doesn’t understand what that field does.

The iPhone rotates the image automatically, the EXIF information is correct. Think about the sensor being a dumb horizontal plane. It takes the exif info to display it in the correct orientation.