Two classic symptoms
After a conversion, a photo appears sideways in one program and upright in another. Or it looks duller or more saturated than it did on the phone. Both come from the same cause: information stored next to the pixels that some software ignores.
Orientation
A camera sensor writes pixels in a fixed order. When you hold the phone upright, the camera records that fact instead of rotating the pixels. In JPEG that note is the EXIF Orientation tag. ExifTool’s EXIF tag table lists it as tag 0x0112 with eight values: normal, mirror horizontal, rotate 180, mirror vertical, and the four combinations of mirroring with 90-degree rotations. The tag is defined in the Exif standard.
HEIF does it differently. The Nokia HEIF overview lists an image rotation property (irot) that rotates by 90, 180 or 270 degrees, and a clean aperture property for cropping. These are “transformative properties” applied when the image is shown. So a HEIC may carry rotation in the container, in EXIF, or both.
If a converter copies pixels but drops or mishandles those properties, the result looks sideways. If the converter keeps an Orientation tag and the viewer ignores it, same result.
What FromHEIC does
Rotation stored in the HEIC container is applied to the pixels during conversion, and the output’s Orientation is reset to normal. That way the result does not depend on whether the viewing software reads orientation tags. If you want to see what a file stores, the HEIC inspector shows its structure.
Rotating a HEIC itself
The rotate and flip tool offers 90, 180 and 270 degree rotation and horizontal or vertical flips. For HEIC files it rewrites the container’s rotation and mirror properties, leaving the compressed image data untouched, so no re-encoding happens. It reports that and verifies by decoding. A rare consequence is that software which ignores those properties may still display the old orientation. If that matters for your recipient, convert to JPG instead.
The viewer’s rotate button is visual only and does not change the file.
Colour
Colour problems come down to profiles. Pixel numbers mean nothing without knowing which colour space they are in. The ICC specification defines profiles that carry that information. Many iPhone photos use Display P3, which is wider than sRGB.
Typical failures:
- Profile dropped. A P3 image shown as sRGB looks flat.
- Profile ignored by the viewer. Some programs, especially simple ones, treat everything as sRGB.
- Wrong profile attached. Colours shift in an unexpected direction.
What FromHEIC does
By default it converts pixel values to sRGB using the file’s embedded profile, which tends to look correct everywhere. An option keeps the original profile embedded instead. Pick it only if you work in colour-managed software. A more detailed discussion, including bit depth, is in HDR and Display P3.
Check profiles with the colour profile viewer.
Troubleshooting checklist
- Sideways in one app only. That app ignores orientation or container rotation. Use the converted JPG, where rotation has been applied to the pixels, or open the original in a viewer that honours it.
- Sideways in all apps after conversion. Check the source in the viewer. If it also appears wrong there, the original may have been saved that way. Use the rotate tool.
- Colours look dull. Compare against the original in a colour-managed program. If the original is also dull there, the issue is your display or software, not the conversion.
- Colours look too saturated. You probably kept a wide-gamut profile and the viewer is not honouring it, or the opposite. Convert with the default sRGB setting.
Why both fixes are on by default
We chose defaults that work in the most software: rotation baked into pixels, colour in sRGB. They cost something (the wide gamut is clipped and the container orientation info is gone), so they are not always what a professional workflow wants. For that, keep the profile, or use TIFF. For the basics of why you might convert at all, see HEIC vs JPG.