Croissant: semantic_seg = per-pixel category IDs (not instance IDs); keyed to per-scene COCO categories

yonder.croissant.json

@@ -231,7 +231,7 @@
           "@type": "cr:Field",
           "@id": "waypoints/semantic_seg",
           "name": "semantic_seg",
-          "description": "Per-pixel semantic instance IDs. Shape (12, 480, 640) uint16, one channel per yaw. Available for all 167 HSSD scenes; stored as separate {scene}_wp{NNNN}_semantics.npz files under semantics/{scene}/ in the repo.",
+          "description": "Per-pixel category IDs keyed to the per-scene COCO categories array in annotations/{scene}/annotations.json. Shape (12, 480, 640) uint16, one channel per yaw. Available for all 167 HSSD scenes; stored as separate {scene}_wp{NNNN}_semantics.npz files under semantics/{scene}/ in the repo.",
           "dataType": "sc:Integer",
           "isArray": true,
           "arrayShape": "12,480,640"