photoprism/internal/thumb/rotate.go
Michael Mayer 01d4b1ee31 Exif: Refactor JPEG rotation based on orientation flag #1064
We now manually detect and change the rotation, the imaging
autorotation functionality was disabled for our core use-cases.

anymore.
2021-02-21 22:53:25 +01:00

47 lines
1 KiB
Go

package thumb
import (
"image"
"github.com/disintegration/imaging"
)
const (
OrientationUnspecified int = 0
OrientationNormal = 1
OrientationFlipH = 2
OrientationRotate180 = 3
OrientationFlipV = 4
OrientationTranspose = 5
OrientationRotate270 = 6
OrientationTransverse = 7
OrientationRotate90 = 8
)
// Rotate rotates an image based on the Exif orientation.
func Rotate(img image.Image, o int) image.Image {
switch o {
case OrientationUnspecified:
// Do nothing.
case OrientationNormal:
// Do nothing.
case OrientationFlipH:
img = imaging.FlipH(img)
case OrientationFlipV:
img = imaging.FlipV(img)
case OrientationRotate90:
img = imaging.Rotate90(img)
case OrientationRotate180:
img = imaging.Rotate180(img)
case OrientationRotate270:
img = imaging.Rotate270(img)
case OrientationTranspose:
img = imaging.Transpose(img)
case OrientationTransverse:
img = imaging.Transverse(img)
default:
log.Debugf("rotate: invalid orientation %d", o)
}
return img
}