Unable to set proper orientation of 3d Model in AR augmented face

Unable to Set Proper Orientation of 3D Model in AR Augmented Face

Introduction

Augmented Reality (AR) face filters are becoming increasingly popular, allowing users to overlay 3D models onto their faces. However, a common challenge is achieving the correct orientation of the 3D model in relation to the user’s face. This article explores the causes of this issue and provides solutions to ensure accurate model placement.

Understanding the Problem

The core issue stems from the mismatch between the 3D model’s coordinate system and the AR face tracking system’s coordinate system. The model might be aligned in a different direction from the user’s face, resulting in an awkward or unnatural appearance. This could be due to:

• Incorrect Model Orientation: The 3D model might be created with a different axis alignment than the AR system expects.
• Mismatched Coordinate Systems: The AR tracking system and the 3D model might use different coordinate systems, leading to orientation discrepancies.
• Insufficient Face Tracking Data: The AR system might not have sufficient data points to accurately track the user’s face, resulting in inaccurate model positioning.

Troubleshooting and Solutions

1. Check Model Orientation

The first step is to ensure the 3D model itself is correctly oriented. You can use a 3D modeling software to check the model’s axes and adjust them accordingly. For example, if the model is facing the wrong direction, you can rotate it along the Y-axis.

2. Align Coordinate Systems

The AR platform you use likely has a specific coordinate system for placing objects. Consult the platform’s documentation and ensure that the 3D model’s coordinate system matches. If necessary, you can use transformations in your code to convert the model’s coordinates to the platform’s system.

// Example code snippet (JavaScript)
const model = scene.createModel();
// Rotate the model by 90 degrees around the Y-axis
model.rotateY(Math.PI / 2); 

3. Improve Face Tracking

If the AR system struggles to track the user’s face accurately, it can lead to orientation problems. You can try these methods:

• Optimize Lighting: Good lighting conditions help improve face tracking accuracy.
• Use High-Quality Camera: A camera with high resolution and frame rate can enhance tracking capabilities.
• Adjust Tracking Parameters: Some AR platforms allow you to adjust tracking parameters to improve accuracy.

Example Scenario

Consider an AR face filter that places a virtual crown on the user’s head. If the crown is oriented incorrectly, it might appear upside down or tilted at an odd angle. To solve this, you would need to:

• Ensure the crown model’s Y-axis points upwards.
• Confirm that the AR platform uses the same coordinate system for placing objects.
• Check if the face tracking accuracy is adequate and optimize lighting conditions if necessary.

Comparison Table

Conclusion

Successfully orienting 3D models in AR face filters requires understanding the interplay between the model’s coordinate system, the AR platform’s system, and the accuracy of face tracking. By carefully addressing these factors, developers can create immersive and engaging AR experiences with correctly positioned 3D objects.