3D Scene Graph (3DSG) generation plays a pivotal role in spatial understanding and affordance perception. To mitigate generalization issues from data scarcity, joint-embedding and generative proxy tasks are proposed to pre-train 3DSG representations on predicate label-free datasets. Currently, generative pre-training usually bypasses the semantic corruption caused by the geometric augmentations in joint-embedding, but cannot avoid a negative problem ``Geometric Shortcut." In this problem, exposing dense object spatial and scale priors will induce models to trivially reconstruct scenes by interpolating object positions, rather than learning the underlying topological constraints provided by edges. To address this issue, we propose a Topological Layout Learning (ToLL) for 3DSG generation pretraining framework. In detail, we design an Anchor-Conditioned Topological Geometry Reasoning. It adopts a recurrent GNN to recover the global layout of zero-centered subgraphs (the non-visible spatial features) by one anchor with sparse spatial prior. Considering the absence of spatial layout information within the objects, it creates an information bottleneck, compelling our model to recover the full scene layout by leveraging predicate representation learning. Moreover, we construct a Structural Multi-view Augmentation to avoid semantic corruption, enhancing 3DSG representations via self-distillation. The extensive experiments on special dataset demonstrate that our ToLL could often improve 3DSG pertaining quality, outperforming state-of-the-art baselines.
Figures & tables
Fig. 1: Proxy task scheme comparison of 3DSG generation: (a) cross-modal Vision-Language representation, (b) trivial scene generation, (c) non-trivial scene generation, i.e. , our ToLL.
Fig. 2: The motivation of designing Anchor-Conditioned Topological Geometric Reasoning (ACTGR). We observe that exposing complete object geometries (shape, scale, and location) will trigger shortcut learning, causing edge encoder and relative message gradients (plotted by red curves) drop sharply. In contrast, ACTGR can effectively avoid this problem (refer to the blue curves).
Fig. 3: Our 3D Scene Graph Pretraining scheme via Topological Layout Learning with Structural Multi-view Augmentation.
Role
View ID
Source Input
Point M-Ratio
Edge M-Ratio
Objective
Student
Sv1
Origin
0.8
0.2
Prediction / Gradient Update
Sv2
Augmented
0.8
0.6
Sv3
Origin
0.8
0.6
Teacher
Tv4
Origin
0.2
0.2
Target Generation (EMA)
Tv5
Augmented
0.1
0.1
TABLE I: View settings. Source Input indicates whether the input points are from the original data or augmented ones. M-Ratio denotes the masking ratio. The ACTGR strategy is exclusively implemented on the Sv1 view.
Baselines
Pre-training Method
Object
Predicate
Triplet
SGCLs
PredCLs
A@1
A@5
A@1
A@3
mA@1
mA@3
mA@50
mA@100
mR@20
mR@50
mR@20
mR@50
SGPN pn [ 3 ]
×
50.32
74.56
89.89
98.15
40.63
63.41
52.74
65.58
19.7
22.6
32.1
38.4
SGFN pn [ 10 ]
×
53.67
77.18
90.19
98.17
41.89
70.82
58.37
67.61
20.5
23.1
46.1
54.8
SGFN pt
×
56.04
79.37
89.22
97.65
46.69
71.84
60.05
70.26
29.3
30.8
55.7
62.1
VL-SAT pn [ 7 ]
×
55.66
78.66
89.81
98.45
54.03
77.67
65.09
73.59
31.8
32.4
57.8
64.2
VL-SAT pt
×
57.84
78.69
89.76
98.13
52.43
73.35
63.55
72.48
30.3
32.8
54.7
63.8
TABLE II: Comparisons with state-of-the-arts on the 3DSSG dataset. The inference model backbones are denoted by symbols: “ pn ” for PointNet and “ pt ” for PointTransformer. “ PointDif ”: Weights of object encoder initialized with PointDif [ 40 ] . “ ToLL ” or “ ToLL++ ”: Weights of complete 3DSG encoders initialized with our ToLL. “ +MLP only ”: Only MLP heads are fine-tuned.
Method
Pre-training Method
Predicate Classification Metrics
Triplet Classification Metrics
Head (mA@3 / mA@5)
Body (mA@3 / mA@5)
Tail (mA@3 / mA@5)
Unseen (A@50 / A@100)
Seen (A@50 / A@100)
SGFN pn [ 10 ]
×
95.08 / 99.38
70.02 / 87.81
38.67 / 58.21
22.59 / 35.68
71.44 / 80.11
SGFN pt
×
96.18 / 99.46
76.74 / 87.41
48.25 / 62.73
25.54 / 46.69
72.87 / 80.08
VL-SAT pn [ 7 ]
×
96.31 / 99.21
80.03 / 93.64
52.38 / 66.13
31.28 / 47.26
75.09 / 82.25
VL-SAT pt
×
95.97 / 98.92
78.75 / 88.84
54.44 / 68.90
32.87 / 46.32
77.28 / 83.37
CCL-3DSG pn [ 8 ]
×
98.54 / 99.78
84.72 / 96.03
61.24 / 75.91
36.72 / 52.47
80.58 / 88.92
TABLE III: Performance on Predicate Classification (Head, Body, Tail) and Triplet (Zero-Shot setting). “ pn ” for PointNet and “ pt ” for PointTransformer. “ ToLL ” or or “ ToLL++ ”: Weights of complete 3DSG backbone initialized with our ToLL.
Fig. 4: Predicate A@1 for all predicate categories.
Fig. 5: Predicate A@1 for all predicate categories.