Troubleshooting

Model access error or HTTP 401/403. Request access to facebook/sam3 and use a token from the approved account. A valid token from a different account is insufficient. For existing labels, set both image_exists=True and label_exists=True to avoid model loading.

SAM 3 import error. Install segment-lidar[sam3] in the same Python environment used to run the script. For ground filtering, install segment-lidar[csf].

The output is mostly -1. Inspect the RGB raster first. For a pinhole camera, verify world-to-camera R and t, positive camera Z, image size, focal length, and distance_threshold. For top view, confirm the image and label raster share dimensions and that cached rasters cover the points. Unlabeled raster pixels also yield -1.

Pinhole image is empty or cropped. Set the camera center and rotation so the cloud is in front of the camera. Lower fx/fy for a wider field of view, raise width/height, or move the camera back. Check the numerical example in Pinhole camera guide before using survey coordinates.

The pinhole labels reach points behind the visible surface. The raster uses the nearest point for color, but label transfer assigns a pixel’s label to every point that projects there. Inspect extra views or apply your own visibility check if this affects the application.

A cached raster gives different labels. Reuse the same camera matrices and depth threshold for pinhole views. For top views, prefer a saved raster with its GeoTIFF spatial transform. Older unreferenced top view rasters need the original XY origin and resolution.

Interactive camera error. PinholeView(interactive=True) is not implemented in the 0.3 series. Supply explicit matrices as in Pinhole camera guide.