Bivouac.com   Home     Help   Index     Login
How to Normalize Photo Rotation # 1167 Back to Directory   Review Date:2020.03.19
Help Category: Photos

Summary: How to normalize the rotation of a photo that appears sideways in bivouac.

Instructions:
Vertical photos taken on cell phones then uploaded to bivouac come out sideways unless you normalize them. The problem is that the cell phone doesn't truly rotate the photo, instead it just sets a flag telling newer display programs to do the rotation dynamically. A better solution is to rewrite the photo so proper display doesn't depend on that tricky EXIF flag.

If you see one that is sideways, here's how to fix it. Right click on the photo to save it in downloads. Then go into downloads, and display the photo. Then resize it slightly, and save a copy. This causes it to be normalized. Then upload the copy. I have tested this with Windows 10 photo viewer and with Macbook "Preview" photo viewer.

Here's the explanation. When you take a photo vertically on your phone, behind the scenes it is sideways. But it looks OK on the phone because the phone sets a flag to rotate 90 degrees at display time. The latest operating systems like Windows 10 also read that flag, so everything looks ok. But Bivouac, and other older systems don't read that flag, and so the true situation becomes apparent. What you want is to rewrite the photo such that it is normalized and requires zero rotation at display time. This can be done by a variety of programs, but the easiest is to just go into a photo viewer and resize the photo slightly. This causes it to be rewritten and normalized. Note that just using the "rotate" function may not rewrite the actual photo.

See the comment Resize will normalize photos in the photo orientation discussion.