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REVIEW 4 major objections 5 minor 48 references

OLiDM: Object-aware LiDAR Diffusion Models for Autonomous Driving

T0 review · 4 major / 5 minor · reviewed 2026-08-11 · deepseek-v4-flash

Pith's one-line read OLiDM generates LiDAR scenes by first generating controllable foreground objects, then conditioning the scene on them, improving fidelity and downstream detection.

desk verdict Solid engineering contribution with a real two-stage object-to-scene architecture, but the KITTI-360 object-fidelity claim is undermined by using the same SECOND detector for both training data and evaluation. read the letter →

arxiv 2412.17226 v1 pith:3KU3TB3G submitted 2024-12-23 cs.CV cs.RO

classification cs.CVcs.RO
keywords LiDARgenerationdiffusionmodelsobject-awareautonomousdrivingrangeimage3Dobjectdetectiondataaugmentationpointcloud
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

The paper introduces OLiDM, a diffusion framework that generates LiDAR point clouds for autonomous driving at two levels: individual foreground objects and full scenes. Its central claim is that by generating foreground objects first, with text and 3D-box conditions, and then using those objects to guide scene generation, the model produces LiDAR data that is closer to real sensor output than prior whole-scene generators. On KITTI-360 it reports lower FPD and JSD than LiDARGen, R2DM, and UltraLiDAR, and on nuScenes it reports that augmenting training data with its synthetic objects raises 3D detector mAP and NDS. The reason to care is that high-fidelity, controllable synthetic LiDAR could reduce costly real-data collection and annotation for self-driving perception.

What carries the argument

The central machinery is a two-stage diffusion pipeline: an object denoiser, a voxel-based diffusion transformer, that takes CLIP text embeddings and a Fourier-embedded 3D box as conditions, and a scene-level U-Net denoiser over range images, steered by a zero-convolution scene controller that injects the generated object range image. OSA computes category-wise binary masks from the object conditions and uses them to form c-channel masked range images, with an extra diffusion loss on those masked channels to align features within each semantic subspace.

What would settle it

Train an independent object detector, or use human labels, to count and compare objects in OLiDM-generated KITTI-360 scenes against the real-data benchmark of 9.06 boxes per scene; if the independent count does not approach that number while SECOND does, the claimed object fidelity is an artifact of the evaluation detector. Alternatively, fine-tune a detector on OLiDM-only synthetic data and evaluate on real KITTI-360; poor real-world performance would indicate the generated objects do not capture the distribution the paper claims.

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Extended reading notes

Core claim

OLiDM's central claim is that foreground objects, not whole scenes, should be the unit of LiDAR generation. The Object-Scene Progressive Generation (OPG) module first denoises object point clouds conditioned on a text description and a 3D bounding box, then projects those objects into a range image that a scene controller feeds into the scene denoiser. The Object Semantic Alignment (OSA) module adds per-category masked channels to the range image so the diffusion loss is balanced across semantic subspaces. The paper reports that this object-first, scene-second design yields the best FPD and JSD on KITTI-360, with OLiDM exceeding UltraLiDAR by 17.5 in FPD, and that the generated objects improve downstream 3D detection on nuScenes by 2.4% mAP and 1.9% NDS.

Load-bearing premise

The premise that SECOND detector outputs are an unbiased definition of real foreground objects is load-bearing: if SECOND systematically misses or double-counts objects, both the training database of KITTI-360 objects and the object-level evaluation are biased in the same direction.

Editorial extensions

If this is right

  • If correct, OLiDM gives a single pipeline that outputs both a LiDAR scene and the 3D object annotations for the objects it placed, since the objects are generated first.
  • It enables user control of object category, description, position, and size, which can be used to create rare or corner-case scenarios for perception testing.
  • The reported sparse-to-dense completion gains suggest the same conditional mechanism can upsample low-beam LiDAR to high-beam density with better semantic preservation.
  • The downstream improvement over GT-Aug indicates that object-first synthetic data can serve as a data augmentation source for 3D detectors.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • The object-first design could be applied to other sensor modalities such as radar or event cameras, where foreground-background imbalance also exists, though the paper does not test this.
  • Because object crops are generated before the scene, the framework could, in principle, be extended to insert a requested number of objects per category at desired locations, enabling stress-testing of perception systems; the paper only demonstrates uniform and prompted sampling.
  • The reliance on SECOND detections for the KITTI-360 object database suggests that using ground-truth annotations instead could shift both training and evaluation, and it is an open question how the reported object-level metrics would change under an independent detector.
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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

4 major / 5 minor

Summary. OLiDM proposes an object-aware LiDAR diffusion framework that generates foreground objects first, conditioned on CLIP text embeddings and Fourier-encoded 3D boxes, and then generates a full scene from a range image using a scene controller and an Object Semantic Alignment (OSA) loss. Experiments on KITTI-360 report strong scene-level FPD/JSD, object-level Chamfer/JSD/#Box numbers, sparse-to-dense completion results, and downstream nuScenes detection improvements over GT-Aug and LiDAR-Aug. The paper's central novelty is the object-first, scene-second progressive generation, which is reasonable and potentially useful, but the object-level evaluation is weakened by a training/evaluation circularity and the abstract contains quantitative claims that do not match the reported tables.

Significance. If the claims hold, OLiDM would be a practical contribution because it is the first LiDAR generator in this line that separates foreground-object generation from background-scene generation and provides initial object annotations for downstream tasks. The scene-level FPD/JSD improvements and the nuScenes detection gains are externally benchmarked and deserve credit: the FPD improvement over UltraLiDAR (25.1 to 7.60 in Table 1) is large, and the CenterPoint mAP gain of 2.9 points over a strong baseline is a concrete, falsifiable result. However, the headline claim of high-fidelity object generation on KITTI-360 is not yet established, because the object training database and the object-level evaluation both rely on the same SECOND detector. The paper also omits error bars and has abstract numbers inconsistent with Tables 3 and 4. The architecture is original, and the OSA idea is clearly presented, but the experimental validation needs to be strengthened before the central object-level claim can be accepted.

major comments (4)
  1. [§4.2, Appendix A] The object-level evaluation is circular. Appendix A states that the KITTI-360 object training database is built by running SECOND (trained on KITTI) on KITTI-360, and Section 4.2 states that the object-level evaluation uses the same detector family to identify and count generated objects, with the reference value #Box = 9.06 being the average SECOND-detected box count in real scenes. Consequently, the low CD/JSD values and the #Box count in Table 2 may reflect the model reproducing SECOND's detection biases (typical box shapes, easy poses, false-positive patterns) rather than geometric or semantic fidelity to human-annotated objects. The comparison is also asymmetric, because LiDARGen and R2DM were not trained on this detector-derived object distribution. Please re-evaluate object-level metrics against KITTI-360 ground-truth annotations or an independent detector, and report, for example, point-to-surface distance to annotated 3D boxes and per-category recall/precision of detected generated objects.
  2. [Abstract, Tables 3 and 4] The abstract's quantitative claims do not match the reported tables. The claim of a '57.47% increase in semantic IoU' in sparse-to-dense completion is not a relative increase: Table 3 reports semantic IoU 22.46 for LiDARGen and 79.93 for OLiDM, which is an absolute increase of 57.47 percentage points and a relative increase of about 256%. The claim of '2.4% in mAP and 1.9% in NDS' is also not directly supported by Table 4, where PointPillars shows +1.9 mAP / +2.8 NDS and CenterPoint shows +2.9 mAP / +2.7 NDS; neither detector gives 1.9 NDS, and the mAP value is only the average of two detectors. Please state the exact aggregation rule or correct the abstract.
  3. [Tables 1–4] No random seeds, number of runs, or confidence intervals are reported for any quantitative result. Diffusion sampling is stochastic, and several reported differences are small (e.g., JSD 0.49 vs. 0.42 in Table 1; NDS differences in Table 4), so without repeated runs it is unclear whether these differences are significant. Please run at least three seeds for the main generation and detection experiments and report mean and standard deviation, or an equivalent statistical statement.
  4. [§4.2, Table 2] The description of the object-level reference set is incomplete. The text reports CD, SS, and JSD for 'foreground objects' and states that 'we sample 1000 objects for the evaluation,' but it does not state what the reference point clouds are, how the generated objects are extracted (e.g., by cropping detected boxes), or how each generated object is matched to a real object for the Chamfer Distance computation. If the real reference objects are also the SECOND-extracted patches used in Appendix A, then the CD and SS numbers are not an independent measure of fidelity. Please specify the full evaluation protocol.
minor comments (5)
  1. [§4.1] The sentence 'R2DM is our baseline, with range image inputs (Sec.3.1 w = 1024)' is unclear: R2DM is a prior method, and Section 3.1 does not define the symbol w. If R2DM is reimplemented, state the reimplementation details and the source of the numbers in Table 1.
  2. [§3.3, Eq. (9)] The OSA loss in Eq. (9) is written without the scene controller or the object-conditioned features used in Eq. (8), but the text says Eq. (9) is used jointly with Eq. (8). Please clarify whether Eq. (9) is computed with the same conditioned denoiser and specify how the mask M is obtained during training (e.g., from ground-truth object boxes or from detector outputs).
  3. [§3.3] The text refers to 'fig. 17' when first introducing the OSA motivation, but Figure 17 is in the appendix and is not called out until later. Please renumber or move the reference so the figure is introduced at the appropriate point.
  4. [Table 3] The header 'Reflectence' appears to be a typo for 'Reflectance'.
  5. [§4.1 and Table 2] The notation OLiDM, OLiDM−, OLiDMT, and OLiDMB is used in Table 2, but the caption only explains the abbreviations loosely. Please define each row explicitly in the caption or in the text before the table.

Circularity Check

1 steps flagged · score 3.0 of 10

Object-level KITTI-360 claim is partially circular: both the object training database and the object evaluation metric are built from the same SECOND detector, so high object-level scores partly reflect a closed detector loop; scene-level and nuScenes downstream claims remain independent.

  1. self definitional [Appendix A (Training Dataset) and Section 4.2 (Object-Aware LiDAR Generation), Table 2]
    "Appendix A: "As for KITTI-360, we utilize a well-trained 3D detector ( i.e., SECOND [38] trained on KITTI [12]) to identify foreground objects on KITTI360. We also sample 55k real LiDAR objects from these detected objects." Section 4.2: "We utilize a well-trained 3D detector (Yan, Mao, and Li 2018) to identify foreground objects within LiDAR scenes.""

    On KITTI-360, 'real foreground objects' are operationally defined as SECOND detections: Appendix A builds the 55k-object training set by running SECOND on KITTI-360, and Section 4.2 evaluates object-level fidelity with that same SECOND detector. The paper's #Box reference value 9.06 is the mean number of SECOND-detected boxes in real scenes, so 'approaching 9.06' means matching the output distribution of the very detector used to create the training patches. Because OLiDM's object denoiser is trained to reproduce SECOND-detected patches, the high CD, SS, JSD, and #Box numbers measure closeness to the detector's own output distribution, not to an independent human-annotated object distribution.

full rationale

The paper's central scene-level generation results are not circular: FPD, JSD, and MMD on KITTI-360 compare generated range/BEV point distributions against real LiDAR using external feature representations, and OLiDM is not optimized against those metrics. The nuScenes downstream experiments are also independent: the object database there uses ground-truth annotations, and the improved mAP/NDS of PointPillars and CenterPoint is measured by external detectors on real validation data. The one genuinely load-bearing circular element is the object-level evaluation on KITTI-360, where the training target and the evaluation instrument are both SECOND detections. That loop weakens the claim that OLiDM produces 'high-fidelity' foreground objects in an absolute sense; it more directly demonstrates fidelity to SECOND's detected-object distribution. Since the object-level claim is a headline contribution, this partial circularity prevents a 0-2 score, but the independent scene-level and downstream evidence keep the overall derivation from collapsing to a fit, so a moderate score of 3 is appropriate.

Assumptions & free parameters 6 free parameters · 7 assumptions · 0 invented entities

The central claim rests on the standard diffusion framework plus a set of pretrained encoders and a detector-derived object database. No new physical entities are introduced; OPG and OSA are algorithmic modules. The most consequential unstated input is the SECOND detector, which defines both training objects and evaluation objects on KITTI-360.

free parameters (6)
  • voxel size V = 32
    Input voxel resolution for the object denoiser, inherited from DiT-3D (Appendix A); sets the spatial granularity of generated objects.
  • object point count N = 1024
    Number of points per generated object, inherited from DiT-3D (Appendix A); limits object density and detail.
  • range image height H = 64 for KITTI-360, 32 for nuScenes
    Scene range image resolution (Appendix A); affects scene detail and computational cost.
  • scene training steps and batch = 300k steps, batch 16, lr 1e-5
    Training schedule for the scene denoiser and controller (Appendix A); chosen by hand with no sensitivity study.
  • OSA loss weight = not reported
    The total loss combining Eq. (8) and Eq. (9) is not specified, so the relative weight is an undisclosed tuning choice.
  • number of diffusion timesteps = not reported
    The diffusion schedule for both denoisers is standard DDPM, but the timestep count is not stated in the paper.
assumptions (7)
  • standard math DDPM noise-adding and denoising objective
    Object and scene losses (Eqs. 6, 8, 9) use the standard Gaussian diffusion formulation from Ho et al. 2020.
  • standard math Cross-attention and zero-convolution designs transfer from image diffusion to LiDAR range images
    The object denoiser uses cross attention from DiT-3D and the scene controller uses zero convolutions from ControlNet; prior architectural assumptions are carried over.
  • domain assumption CLIP text embeddings and BLIP2 captions are semantically meaningful for LiDAR objects
    Appendix A uses BLIP2 to caption cropped LiDAR patches and CLIP embeddings as text conditions; if captions misrepresent sparse LiDAR geometry, the conditioning signal is noisy.
  • domain assumption SECOND detections define ground-truth foreground objects on KITTI-360
    Appendix A extracts 55k objects from SECOND detections; the paper uses these as object-level ground truth for training and CD evaluation.
  • domain assumption OpenShape cosine similarity is a valid object-quality metric
    Semantic Similarity is computed with OpenShape embeddings; this assumes the embedding space reflects driving-relevant semantic fidelity.
  • ad hoc to paper Splitting range-image features into category masks reduces spatial misalignment
    Eq. (9) adds a loss on c-channel masked range images; the benefit is empirical and not independently justified.
  • ad hoc to paper Object-first, scene-later progressive generation helps rather than hurts scene fidelity
    The OPG order is a design choice; the paper does not compare against scene-first or joint generation.

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Cite this review

Pith. "Pith review of OLiDM: Object-aware LiDAR Diffusion Models for Autonomous Driving." pith.science (2026). https://pith.science/paper/3KU3TB3G

@misc{pith2026241217226,
  author       = {Pith},
  title        = {Pith review of: OLiDM: Object-aware LiDAR Diffusion Models for Autonomous Driving},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/3KU3TB3G}},
  note         = {Machine review of arXiv:2412.17226}
}
read the original abstract

To enhance autonomous driving safety in complex scenarios, various methods have been proposed to simulate LiDAR point cloud data. Nevertheless, these methods often face challenges in producing high-quality, diverse, and controllable foreground objects. To address the needs of object-aware tasks in 3D perception, we introduce OLiDM, a novel framework capable of generating high-fidelity LiDAR data at both the object and the scene levels. OLiDM consists of two pivotal components: the Object-Scene Progressive Generation (OPG) module and the Object Semantic Alignment (OSA) module. OPG adapts to user-specific prompts to generate desired foreground objects, which are subsequently employed as conditions in scene generation, ensuring controllable outputs at both the object and scene levels. This also facilitates the association of user-defined object-level annotations with the generated LiDAR scenes. Moreover, OSA aims to rectify the misalignment between foreground objects and background scenes, enhancing the overall quality of the generated objects. The broad effectiveness of OLiDM is demonstrated across various LiDAR generation tasks, as well as in 3D perception tasks. Specifically, on the KITTI-360 dataset, OLiDM surpasses prior state-of-the-art methods such as UltraLiDAR by 17.5 in FPD. Additionally, in sparse-to-dense LiDAR completion, OLiDM achieves a significant improvement over LiDARGen, with a 57.47\% increase in semantic IoU. Moreover, OLiDM enhances the performance of mainstream 3D detectors by 2.4\% in mAP and 1.9\% in NDS, underscoring its potential in advancing object-aware 3D tasks. Code is available at: https://yanty123.github.io/OLiDM.

Figures

Figures reproduced from arXiv: 2412.17226 by the authors.

Figure 1
Figure 1. To assess the quality of foreground objects, we utilize an off-the-shelf 3D detector ( [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. Pipeline of OLiDM. OLiDM is designed to generate diverse, controllable, and realistic LiDAR point clouds at both object and scene levels through the Object-Scene Progressive Generation (OPG) process. Object Generation: OPG carefully combines conditions such as text descriptions and 3D geometric context to accurately model LiDAR objects. Scene Genera￾tion: OPG then incorporates these generated objects as specific con… view at source ↗
Figure 3
Figure 3. The Object Semantic Alignment (OSA) module aligns object features based on their semantic space, enhanc￾ing the foreground object generation and contributing to the overall quality of the generated LiDAR scenes. foreground objects, resulting in the higher-quality genera￾tion. Specifically, given a frame of range image I ∈ R H×W×2 , OSA first calculates binary mask M ∈ R H×W×c accord￾ing to foreground objects P, wher… view at source ↗
Figures from the paper (14 more)
Figure 4
Figure 4. Figure 4: Qualitative comparison against baselines on LiDAR generation. We compare with LiDARGen, UltraLiDAR and include real LiDAR for reference. OLiDM generates LiDAR data with more realistic sparsity and beam patterns. Red, Blue and Green boxes are the detected objects (car, …
Figure 5
Figure 5. Figure 5 [PITH_FULL_IMAGE:figures/full_fig_p007_5.png]
Figure 6
Figure 6. Figure 6: OLiDM controls contents at both object and scene levels. OLiDM guarantees that the desired 3D objects are accurately represented in the final LiDAR scenes. tion of desired LiDAR scenes, including extremely crowded scenarios. This advantage demonstrates our ability to g…
Figure 7
Figure 7. Figure 7: Qualitative comparison between OLiDM w/o and w/ OSA. OSA significantly mitigates the noise in the point cloud at the foreground-background boundary areas, making the foreground object more clearly separated from the background scene [PITH_FULL_IMAGE:figures/full_fig_p…
Figure 8
Figure 8. Figure 8: Qualitative results about object-level genera￾tion on KITTI360. OLiDM controls the generation of Li￾DAR objects with different 3D location and text prompts. The farther away an object is, the sparser the point clouds are. For the scene-level generation, we set the heig…
Figure 9
Figure 9. Figure 9: LiDAR scanning patterns vary across different 3D [PITH_FULL_IMAGE:figures/full_fig_p011_9.png]
Figure 10
Figure 10. Figure 10: Qualitative results about cars conditioned on various positions. OLiDM controls the generation of Li￾DAR objects with different 3D location. The farther away an object is, the sparser the point clouds are. than LiDARGen [47], yet only 16% longer than R2DM [28]. Meanwh…
Figure 11
Figure 11. Figure 11: Sparse-to-dense LiDAR Completion. We use RangeNet-53 to obtain segmentation results [PITH_FULL_IMAGE:figures/full_fig_p012_11.png]
Figure 12
Figure 12. Figure 12: Sparse-to-dense LiDAR Completion. We use RangeNet-53 to obtain segmentation results [PITH_FULL_IMAGE:figures/full_fig_p013_12.png]
Figure 13
Figure 13. Figure 13: Partial LiDAR Completion [PITH_FULL_IMAGE:figures/full_fig_p014_13.png]
Figure 14
Figure 14. Figure 14: Partial LiDAR Completion [PITH_FULL_IMAGE:figures/full_fig_p015_14.png]
Figure 15
Figure 15. Figure 15: Qualitative results about object-level generation on nuScenes. OLiDM controls the generation of LiDAR objects with different 3D location and text prompts. The farther away an object is, the sparser the point clouds are [PITH_FULL_IMAGE:figures/full_fig_p016_15.png]
Figure 16
Figure 16. Figure 16: Qualitative results about scene-level generation on KITTI-360. OLiDM controls the generation of LiDAR scenes by conditioning foreground objects. black boxes indicate the given object locations as conditions while the red boxes are the detected ones on the generated Li…
Figure 17
Figure 17. Figure 17: OLiDM for conditional LiDAR scene generation. OLiDM is capable of handling versatile conditions, achieving realistic and high-fidelity LiDAR data across various conditional generation tasks [PITH_FULL_IMAGE:figures/full_fig_p017_17.png]

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Reference graph

Works this paper leans on

48 extracted references · 26 canonical work pages

  1. [1]

    Achlioptas, P.; Diamanti, O.; Mitliagkas, I.; and Guibas, L. 2018. Learning representations and generative models for 3d point clouds. In International conference on machine learning, 40--49. PMLR

  2. [2]

    Bai, Y.; Fei, B.; Liu, Y.; Ma, T.; Hou, Y.; Shi, B.; and Li, Y. 2024. RangePerception: Taming LiDAR Range View for Efficient and Accurate 3D Object Detection. Advances in Neural Information Processing Systems, 36

  3. [3]

    Caccia, L.; Van Hoof, H.; Courville, A.; and Pineau, J. 2019 a . Deep generative modeling of lidar data. In 2019 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 5034--5040. IEEE

  4. [4]

    Caccia, L.; Van Hoof, H.; Courville, A.; and Pineau, J. 2019 b . Deep generative modeling of lidar data. In 2019 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 5034--5040. IEEE

  5. [5]

    H.; Vora, S.; Liong, V

    Caesar, H.; Bankiti, V.; Lang, A. H.; Vora, S.; Liong, V. E.; Xu, Q.; Krishnan, A.; Pan, Y.; Baldan, G.; and Beijbom, O. 2020. nuscenes: A multimodal dataset for autonomous driving. In Proceedings of the IEEE/CVF conference on computer vision and pattern recognition, 11621--11631

  6. [6]

    X.; Funkhouser, T.; Guibas, L.; Hanrahan, P.; Huang, Q.; Li, Z.; Savarese, S.; Savva, M.; Song, S.; Su, H.; et al

    Chang, A. X.; Funkhouser, T.; Guibas, L.; Hanrahan, P.; Huang, Q.; Li, Z.; Savarese, S.; Savva, M.; Song, S.; Su, H.; et al. 2015. Shapenet: An information-rich 3d model repository. arXiv preprint arXiv:1512.03012

  7. [7]

    Chen, T.; Kornblith, S.; Norouzi, M.; and Hinton, G. 2020. A simple framework for contrastive learning of visual representations. In International conference on machine learning, 1597--1607. PMLR

  8. [8]

    Cheng, W.; Yin, J.; Li, W.; Yang, R.; and Shen, J. 2023 a . Language-guided 3d object detection in point cloud for autonomous driving. arXiv preprint arXiv:2305.15765

Show all 48 references
  1. [9]

    G.; and Gui, L.-Y

    Cheng, Y.-C.; Lee, H.-Y.; Tulyakov, S.; Schwing, A. G.; and Gui, L.-Y. 2023 b . Sdfusion: Multimodal 3d shape completion, reconstruction, and generation. In Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, 4456--4465

  2. [10]

    Geiger, A.; Lenz, P.; Stiller, C.; and Urtasun, R. 2013. Vision meets robotics: The kitti dataset. The International Journal of Robotics Research, 32(11): 1231--1237

  3. [11]

    Han, W.; Tao, R.; Ling, H.; and Shen, J. 2024. Weakly Supervised Monocular 3D Object Detection by Spatial-Temporal View Consistency. IEEE Transactions on Pattern Analysis and Machine Intelligence

  4. [12]

    Ho, J.; Jain, A.; and Abbeel, P. 2020. Denoising diffusion probabilistic models. In Advances in neural information processing systems, volume 33, 6840--6851

  5. [13]

    H.; Vora, S.; Caesar, H.; Zhou, L.; Yang, J.; and Beijbom, O

    Lang, A. H.; Vora, S.; Caesar, H.; Zhou, L.; Yang, J.; and Beijbom, O. 2019. Pointpillars: Fast encoders for object detection from point clouds. In Proceedings of the IEEE/CVF conference on computer vision and pattern recognition, 12697--12705

  6. [14]

    Lee, S.-g.; Kim, H.; Shin, C.; Tan, X.; Liu, C.; Meng, Q.; Qin, T.; Chen, W.; Yoon, S.; and Liu, T.-Y. 2021. PriorGrad: Improving conditional denoising diffusion models with data-dependent adaptive prior. arXiv preprint arXiv:2106.06406

  7. [15]

    Li, J.; Li, D.; Xiong, C.; and Hoi, S. 2022. Blip: Bootstrapping language-image pre-training for unified vision-language understanding and generation. In International Conference on Machine Learning, 12888--12900. PMLR

  8. [16]

    Li, X.; Yin, J.; Li, W.; Xu, C.; Yang, R.; and Shen, J. 2024. Di-v2x: Learning domain-invariant representation for vehicle-infrastructure collaborative 3d object detection. In Proceedings of the AAAI Conference on Artificial Intelligence, volume 38, 3208--3215

  9. [17]

    Li, X.; Yin, J.; Shi, B.; Li, Y.; Yang, R.; and Shen, J. 2023 a . Lwsis: Lidar-guided weakly supervised instance segmentation for autonomous driving. In Proceedings of the AAAI Conference on Artificial Intelligence, volume 37, 1433--1441

  10. [18]

    Li, Y.; Liu, H.; Wu, Q.; Mu, F.; Yang, J.; Gao, J.; Li, C.; and Lee, Y. J. 2023 b . Gligen: Open-set grounded text-to-image generation. In Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, 22511--22521

  11. [19]

    Liao, Y.; Xie, J.; and Geiger, A. 2022. KITTI-360: A novel dataset and benchmarks for urban scene understanding in 2d and 3d. IEEE Transactions on Pattern Analysis and Machine Intelligence, 45(3): 3292--3310

  12. [20]

    Liu, M.; Shi, R.; Kuang, K.; Zhu, Y.; Li, X.; Han, S.; Cai, H.; Porikli, F.; and Su, H. 2023. OpenShape: Scaling Up 3D Shape Representation Towards Open-World Understanding. arXiv preprint arXiv:2305.10764

  13. [21]

    Lugmayr, A.; Danelljan, M.; Romero, A.; Yu, F.; Timofte, R.; and Van Gool, L. 2022. Repaint: Inpainting using denoising diffusion probabilistic models. In Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, 11461--11471

  14. [22]

    Luo, S.; and Hu, W. 2021. Diffusion probabilistic models for 3d point cloud generation. In Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, 2837--2845

  15. [23]

    Meng, Q.; Wang, W.; Zhou, T.; Shen, J.; Van Gool, L.; and Dai, D. 2020. Weakly supervised 3d object detection from lidar point cloud. In European Conference on computer vision, 515--531. Springer

  16. [24]

    P.; Tancik, M.; Barron, J

    Mildenhall, B.; Srinivasan, P. P.; Tancik, M.; Barron, J. T.; Ramamoorthi, R.; and Ng, R. 2021. Nerf: Representing scenes as neural radiance fields for view synthesis. Communications of the ACM, 65(1): 99--106

  17. [25]

    Milioto, A.; Vizzo, I.; Behley, J.; and Stachniss, C. 2019. Rangenet++: Fast and accurate lidar semantic segmentation. In 2019 IEEE/RSJ international conference on intelligent robots and systems (IROS), 4213--4220. IEEE

  18. [26]

    Mo, S.; Xie, E.; Chu, R.; Hong, L.; Niessner, M.; and Li, Z. 2024. Dit-3d: Exploring plain diffusion transformers for 3d shape generation. Advances in Neural Information Processing Systems, 36

  19. [27]

    Nakashima, K.; and Kurazume, R. 2023. LiDAR Data Synthesis with Denoising Diffusion Probabilistic Models. arXiv preprint arXiv:2309.09256

  20. [28]

    Nichol, A.; Jun, H.; Dhariwal, P.; Mishkin, P.; and Chen, M. 2022. Point-e: A system for generating 3d point clouds from complex prompts. arXiv preprint arXiv:2212.08751

  21. [29]

    Ran, H.; Guizilini, V.; and Wang, Y. 2024. Towards Realistic Scene Generation with LiDAR Diffusion Models. In Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, 14738--14748

  22. [30]

    Ronneberger, O.; Fischer, P.; and Brox, T. 2015. U-net: Convolutional networks for biomedical image segmentation. In Medical image computing and computer-assisted intervention--MICCAI 2015: 18th international conference, Munich, Germany, October 5-9, 2015, proceedings, part II...

  23. [31]

    L.; Ghasemipour, K.; Gontijo Lopes, R.; Karagol Ayan, B.; Salimans, T.; et al

    Saharia, C.; Chan, W.; Saxena, S.; Li, L.; Whang, J.; Denton, E. L.; Ghasemipour, K.; Gontijo Lopes, R.; Karagol Ayan, B.; Salimans, T.; et al. 2022. Photorealistic text-to-image diffusion models with deep language understanding. Advances in Neural Information Processing Syste...

  24. [32]

    Sauer, A.; Chitta, K.; M \"u ller, J.; and Geiger, A. 2021. Projected gans converge faster. Advances in Neural Information Processing Systems, 34: 17480--17492

  25. [33]

    W.; Park, S

    Shu, D. W.; Park, S. W.; and Kwon, J. 2019. 3d point cloud generative adversarial network based on tree structured graph convolutions. In Proceedings of the IEEE/CVF international conference on computer vision, 3859--3868

  26. [34]

    Sun, J.; Zhang, Q.; Kailkhura, B.; Yu, Z.; Xiao, C.; and Mao, Z. M. ???? MODELNET40-C: ARobustness BENCHMARK FOR 3D POINT CLOUD RECOGNITION UNDER CORRUPTION

  27. [35]

    Tao, R.; Han, W.; Qiu, Z.; Xu, C.-Z.; and Shen, J. 2023. Weakly supervised monocular 3d object detection using multi-view projection and direction consistency. In Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, 17482--17492

  28. [36]

    Wu, Y.; Wang, Y.; Zhang, S.; and Ogai, H. 2020. Deep 3D object detection networks using LiDAR data: A review. IEEE Sensors Journal, 21(2): 1152--1171

  29. [37]

    Xiong, Y.; Ma, W.-C.; Wang, J.; and Urtasun, R. 2023. Learning Compact Representations for LiDAR Completion and Generation. In Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, 1074--1083

  30. [38]

    Yan, Y.; Mao, Y.; and Li, B. 2018. Second: Sparsely embedded convolutional detection. Sensors, 18(10): 3337

  31. [39]

    Yin, J.; Shen, J.; Chen, R.; Li, W.; Yang, R.; Frossard, P.; and Wang, W. 2024. Is-fusion: Instance-scene collaborative fusion for multimodal 3d object detection. In Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, 14905--14915

  32. [40]

    J.; and Yang, R

    Yin, J.; Shen, J.; Gao, X.; Crandall, D. J.; and Yang, R. 2021. Graph neural network and spatiotemporal transformer attention for 3D video object detection from point clouds. IEEE Transactions on Pattern Analysis and Machine Intelligence, 45(8): 9822--9835

  33. [41]

    Yin, T.; Zhou, X.; and Krahenbuhl, P. 2021. Center-based 3d object detection and tracking. In Proceedings of the IEEE/CVF conference on computer vision and pattern recognition, 11784--11793

  34. [42]

    Y.; Zhang, H.; Pang, R.; Qin, J.; Ku, A.; Xu, Y.; Baldridge, J.; and Wu, Y

    Yu, J.; Li, X.; Koh, J. Y.; Zhang, H.; Pang, R.; Qin, J.; Ku, A.; Xu, Y.; Baldridge, J.; and Wu, Y. 2021. Vector-quantized image modeling with improved vqgan. arXiv preprint arXiv:2110.04627

  35. [43]

    Zhang, L.; Rao, A.; and Agrawala, M. 2023. Adding conditional control to text-to-image diffusion models. In Proceedings of the IEEE/CVF International Conference on Computer Vision, 3836--3847

  36. [44]

    Zhang, X.; Zheng, Z.; Gao, D.; Zhang, B.; Pan, P.; and Yang, Y. 2022. Multi-view consistent generative adversarial networks for 3d-aware image synthesis. In Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, 18450--18459

  37. [45]

    Zhou, L.; Du, Y.; and Wu, J. 2021. 3d shape generation and completion through point-voxel diffusion. In Proceedings of the IEEE/CVF International Conference on Computer Vision, 5826--5835

  38. [46]

    Zyrianov, V.; Zhu, X.; and Wang, S. 2022. Learning to generate realistic lidar point clouds. In European Conference on Computer Vision, 17--35

  39. [47]

    , " * write output.state after.block = add.period write newline

    ENTRY address archivePrefix author booktitle chapter edition editor eid eprint howpublished institution isbn journal key month note number organization pages publisher school series title type volume year label extra.label sort.label short.list INTEGERS output.state before.all...

  40. [48]

    write newline

    " write newline "" before.all 'output.state := FUNCTION n.dashify 't := "" t empty not t #1 #1 substring "-" = t #1 #2 substring "--" = not "--" * t #2 global.max substring 't := t #1 #1 substring "-" = "-" * t #2 global.max substring 't := while if t #1 #1 substring * t #2 gl...

Pith tools

Reviewed August 11, 2026 · model on record in the stance chip above.