Incorrect stabilization behavior when DNG image sequences contain rotation metadata

Is there an existing issue for this?

• I have searched the existing issues

Have you tried the latest dev build?

• I have tried the latest dev build from here

Do you have latest GPU drivers installed?

• I have the latest GPU drivers installed, I'm absolutely sure.

Have you checked the documentation?

• I have read the FAQ and Troubleshooting and didn't find my issue there.

Gyroflow version

1.6.3

What operating system are you using?

macOS 26.2

What GPU are you using?

No response

What happened?

Description:

When using Gyroflow with DNG image sequences that contain rotation metadata, stabilization behaves inconsistently depending on the rotation tag value. This appears to cause mismatches between resolution handling, preview orientation, and stabilization calculations.

Observed Behavior:

I tested three DNG files with the same subject, but different rotation metadata tags:

Rotation = 1 (normal / no rotation)

Rotation = 90°

Rotation = 180°

Case 1: Rotation = 1 (normal)

Everything works as expected.

Case 2: Rotation = 90°

Gyroflow project keeps the original resolution as if the image were not rotated. The video preview from MDK-SDK/FFMpeg rotates the image, however.

The result is a vertical preview with black bars and stabilization doesn't work.

Case 3: Rotation = 180°

Gyroflow appears to expect unrotated sensor data (which makes sense, since gyro/accelerometer sensors rotate together with the device). You can see that X and Y coordinates are exactly mirrored.

However, the video preview and optical flow operate on the rotated image.

This creates a mismatch between stabilization calculations and the visual data.

The resulting stabilization is incorrect.

What we might need to clarify for Gyroflow is:

Clarification and consistent handling of rotation metadata in image sequences. Specifically:

Either rotation metadata should be ignored entirely and images treated as physically stored,

Or rotation should be applied consistently to resolution, preview, optical flow, and stabilization math.

Below are the image sequences with GCSV (the gcsv assume that the device is rotated, so for example, for 180 degree rotation XYZ becomes xyZ, but this might be incorrect, depending on what we decide). Lens profile is also linked.

https://drive.google.com/drive/folders/1g-0_dMm4GDCERNfH8AVCReUgY8pwMpkW?usp=sharing

Relevant log output