Image Orientation¶
Using Exiftool¶
Assuming you have Docker installed and want to run exiftool
with Debian 12 "Bookworm", you can simply run this command to open a terminal:
docker run --rm -v ${PWD}:/test -w /test -ti debian:bookworm bash
This will mount the current working directory as /test
. Of course, you can also specify a full path instead of ${PWD}
.
The available Ubuntu, Debian and PhotoPrism images can be found on Docker Hub:
- https://hub.docker.com/_/ubuntu
- https://hub.docker.com/_/debian
- https://hub.docker.com/r/photoprism/photoprism/tags
Now install exiftool
and any other packages you need, e.g. libheif-examples
to convert HEIF images to JPEG, via apt
:
apt update
apt install -y exiftool libheif-examples
To view the image metadata, run exiftool -n <filename>
and optionally use grep to filter the output:
root@1ad9fb887a4f:/test# exiftool -n IMG_8437.HEIC.jpg | grep ation
File Modification Date/Time : 2022:09:18 08:16:28+00:00
Orientation : 6
Exposure Compensation : 0
root@1ad9fb887a4f:/test# exiftool -n IMG_8437.HEIC | grep ation
File Modification Date/Time : 2022:09:17 16:57:40+00:00
Orientation : 6
Exposure Compensation : 0
HEVC Configuration Version : 1
Min Spatial Segmentation IDC : 0
Rotation : 270
Rotation and Orientation are the important values you should pay attention to and compare. The rotation is in degrees.
Exiftool Parameters¶
-n
displays the raw values without changes-j
will format the output as JSON-g
groups the output by metadata source
Exif Values¶
The numbers used to specify the image orientation are defined as follows:
- = 0 degrees: the correct orientation, no adjustment is required.
- = 0 degrees, mirrored: image has been flipped back-to-front.
- = 180 degrees: image is upside down.
- = 180 degrees, mirrored: image has been flipped back-to-front and is upside down.
- = 90 degrees: image has been flipped back-to-front and is on its side.
- = 90 degrees, mirrored: image is on its side.
- = 270 degrees: image has been flipped back-to-front and is on its far side.
- = 270 degrees, mirrored: image is on its far side.