ImageMagick rotate and flip commands
Rotate and flip images with ImageMagick. Fix sideways phone photos with -auto-orient, rotate by any angle, and understand the difference between -flip and -flop.
Fix a photo that appears sideways
Phones store photos in the sensor's orientation plus an EXIF tag telling viewers how to rotate them. Some software honours that tag, some ignores it — which is why the same file looks correct in one app and rotated in another.
magick input.jpg -auto-orient output.jpg-auto-orient bakes the rotation into the actual pixels and clears the tag, so every viewer agrees.
Do this before cropping. If you crop first, your coordinates are measured against the unrotated image and the crop lands somewhere unexpected.
Rotate by a right angle
magick input.jpg -rotate 90 output.jpg # clockwise
magick input.jpg -rotate 270 output.jpg # counter-clockwise
magick input.jpg -rotate 180 output.jpgRight-angle rotations are lossless in terms of pixel data, though re-encoding a JPEG still costs a generation of quality. If that matters, use jpegtran -rotate 90 instead, which rotates without re-encoding.
Rotate by an arbitrary angle
magick input.jpg -background white -rotate 15 output.jpgA non-right-angle rotation enlarges the canvas and fills the new corners with -background. Set it to none and output PNG if you want those corners transparent:
magick input.png -background none -rotate 15 output.png-flip versus -flop
| Flag | Effect |
|---|---|
-flip | Vertical mirror — top becomes bottom |
-flop | Horizontal mirror — left becomes right |
Nearly everyone guesses these the wrong way round the first time. The one you usually want, for making a photo look like a mirror selfie, is -flop.
Transpose and transverse
magick input.jpg -transpose output.jpg # flip + rotate 90
magick input.jpg -transverse output.jpg # flop + rotate 90Straighten a scanned document
ImageMagick can estimate and correct a small skew automatically:
magick input.jpg -background white -deskew 40% +repage output.jpgThe percentage is a threshold, not an angle. 40% is a reasonable starting point for scanned text on white paper. Add -fuzz 5% -trim afterwards to crop the resulting border.
Batch-fix orientation across a folder
mkdir -p out
for f in *.jpg; do magick "$f" -auto-orient "out/$f"; done