Papers › Mixed Diffusion for 3D Indoor Scene Synthesis

Mixed Diffusion for 3D Indoor Scene Synthesis

31 May 2024arXiv:2405.21066archive 2025-07-28

Siyi Hu, Diego Martin Arroyo, Stephanie Debats, Fabian Manhardt, Luca Carlone, Federico Tombari

Generating realistic 3D scenes is an area of growing interest in computer vision and robotics. However, creating high-quality, diverse synthetic 3D content often requires expert intervention, making it costly and complex. Recently, efforts to automate this process with learning techniques, particularly diffusion models, have shown significant improvements in tasks like furniture rearrangement. However, applying diffusion models to floor-conditioned indoor scene synthesis remains under-explored. This task is especially challenging as it requires arranging objects in continuous space while selecting from discrete object categories, posing unique difficulties for conventional diffusion methods. To bridge this gap, we present MiDiffusion, a novel mixed discrete-continuous diffusion model designed to synthesize plausible 3D indoor scenes given a floor plan and pre-arranged objects. We represent a scene layout by a 2D floor plan and a set of objects, each defined by category, location, size, and orientation. Our approach uniquely applies structured corruption across mixed discrete semantic and continuous geometric domains, resulting in a better-conditioned problem for denoising. Evaluated on the 3D-FRONT dataset, MiDiffusion outperforms state-of-the-art autoregressive and diffusion models in floor-conditioned 3D scene synthesis. Additionally, it effectively handles partial object constraints via a corruption-and-masking strategy without task-specific training, demonstrating advantages in scene completion and furniture arrangement tasks.

PaperPDFCodeCode Syntology ran

In Syntology Open this paper in Syntology's Atlas, the map of the papers in Syntology's graph and their citations.

For agents, Syntology's MCP tool lists every function and class Syntology harvested from this paper and whether it ran (how to connect): get_harvested_code_for_paper(arxiv_id="2405.21066")

Code

Syntology Ran 8 of 10 code samples harvested from 1 repository linked to this paper; 2 have no recorded run. Of those that ran: 1 ran · honoured contract; 1 ran · our draft was wrong; 6 ran with no contract checked.

By repository: official repository: 10 samples from 1 repository, 8 ran. The run record, sample by sample. “Ran” means executed on a synthesized input, not that the code is correct or reproduces the paper.

mit-spark/midiffusion officialmentioned in papermentioned on GitHubpytorchNOASSERTION report

Repository list and official/mentioned flags are the archive's, frozen 2025-07-28. Reachability, where shown, is from one Syntology probe window (2026-09-16 to 2026-09-18); repositories not probed show nothing. GitHub stars are not tracked.

Code Syntology ran Syntology

10 samples harvested; 8 ran; 1 honoured the contract we drafted; 2 have no recorded run. Read from Syntology's graph 2026-09-24; that is when this build read the record, not when the samples ran.

1ran · honoured contract
1ran · our draft was wrong
6ran
2unverified

Licence: 10 of the 10 samples are pointer only, meaning Syntology does not serve that copy's text. This page shows no code text for any sample; each one links to its file in the repository.

Harvested from mit-spark/midiffusion. “Ran” means the sample executed on a synthesized input. It does not mean the output is correct, and nothing here reproduces the paper's results. “Honoured” and “violated” refer to a contract Syntology drafted from the code itself; “our draft was wrong” and “fixture could not drive it” are failures of Syntology's instrument, not of the code.

Each sample ends with its code_sha256, Syntology's identity for that exact code. An agent fetches the stored sample with Syntology's MCP tool get_code(code_sha256="…") (how to connect); click an identity to copy that call.

Repository labels, per sample. official repository: The archive marks this repository official for the paper. named in the paper: The archive records that the paper mentions this repository; it is not marked official. community (archive-listed): In the archive's code links for this paper, not marked official and not recorded as mentioned in the paper. found in paper text by Syntology: Syntology found this repository in the paper's own text; whether it is the authors' implementation is not asserted. community: Not in the archive's code links for this paper; a community repository Syntology harvested. Samples from a repository marked official are listed first. Licence labels name the repository's licence as recorded at harvest. “Pointer only” means Syntology does not serve that copy's text, for one of four reasons: no licence file was found; the licence was not identified; the licence is recorded as permissive but that copy's record is not marked cleared; or the licence is outside the permissive list Syntology serves text under (MIT, Apache-2.0, BSD and similar). Some licences outside that list permit redistribution, such as WTFPL, and GPL-3.0 under its conditions; they are simply not on the list. Hover a licence label for the reason. File links open the file on GitHub at the default branch, which may have changed since the harvest.

axis_aligned_bbox_overlaps_3d mit-spark/midiffusion/midiffusion/networks/loss.py official repository ran licence not identified · pointer only · 5e963c0dc8a616e5 · report
extract_params mit-spark/midiffusion/midiffusion/networks/diffusion_mixed.py official repository ran licence not identified · pointer only · 190bebc842613fd1 · report
freeze_network mit-spark/midiffusion/midiffusion/networks/frozen_batchnorm.py official repository ran licence not identified · pointer only · 00edd28ef6f548e0 · report
get_betas mit-spark/midiffusion/midiffusion/networks/diffusion_ddpm.py official repository ran licence not identified · pointer only · ea8ccee07ccf89b1 · report
get_feature_mask mit-spark/midiffusion/midiffusion/evaluation/utils.py official repository ran licence not identified · pointer only · 9b1c4e6a2ce41fff · report
log_add_exp mit-spark/midiffusion/midiffusion/networks/diffusion_d3pm.py official repository ran fingerprinted licence not identified · pointer only · e532cc2df7cd402f · report
log_categorical mit-spark/midiffusion/midiffusion/networks/diffusion_d3pm.py official repository ran · honoured contract fingerprinted no licence file found · pointer only · f4b18dd8f67674cb · report
normal_kl mit-spark/midiffusion/midiffusion/networks/diffusion_ddpm.py official repository ran · our draft was wrong fingerprinted no licence file found · pointer only · ec4a40e4187ccdac · report
get_feature_extractor mit-spark/midiffusion/midiffusion/networks/feature_extractors.py official repository unverified licence not identified · pointer only · 5d0cae21e2c438ad · report
log_1_min_a mit-spark/midiffusion/midiffusion/networks/diffusion_d3pm.py official repository unverified licence not identified · pointer only · f7bc6629510abc28 · report

Tasks

DenoisingIndoor Scene Synthesis

Results from the paper archive 2025-07-28

No leaderboard rows for this paper in the archive.

Methods

DiffusionSET

Report a problem or propose a change · a person checks every report against the paper or source before anything changes; decisions are listed on /corrections