Papers › PCL: Proposal Cluster Learning for Weakly Supervised Object Detection

PCL: Proposal Cluster Learning for Weakly Supervised Object Detection

9 Jul 2018arXiv:1807.03342archive 2025-07-28

Peng Tang, Xinggang Wang, Song Bai, Wei Shen, Xiang Bai, Wenyu Liu, Alan Yuille

Weakly Supervised Object Detection (WSOD), using only image-level annotations to train object detectors, is of growing importance in object recognition. In this paper, we propose a novel deep network for WSOD. Unlike previous networks that transfer the object detection problem to an image classification problem using Multiple Instance Learning (MIL), our strategy generates proposal clusters to learn refined instance classifiers by an iterative process. The proposals in the same cluster are spatially adjacent and associated with the same object. This prevents the network from concentrating too much on parts of objects instead of whole objects. We first show that instances can be assigned object or background labels directly based on proposal clusters for instance classifier refinement, and then show that treating each cluster as a small new bag yields fewer ambiguities than the directly assigning label method. The iterative instance classifier refinement is implemented online using multiple streams in convolutional neural networks, where the first is an MIL network and the others are for instance classifier refinement supervised by the preceding one. Experiments are conducted on the PASCAL VOC, ImageNet detection, and MS-COCO benchmarks for WSOD. Results show that our method outperforms the previous state of the art significantly.

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="1807.03342")

Code

Syntology Ran 1 of 7 code samples harvested from 1 repository linked to this paper; 6 have no recorded run. Of those that ran: 1 ran · honoured contract.

By repository: official repository: 7 samples from 1 repository, 1 ran. The run record, sample by sample. “Ran” means executed on a synthesized input, not that the code is correct or reproduces the paper.

ppengtang/oicr officialmentioned in papermentioned on GitHubpytorchMIT report
ppengtang/pcl.pytorch mentioned on GitHubpytorchMIT report
JoegameZhou/mPanGu-Alpha-53 mindsporeNOASSERTION 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

7 samples harvested; 1 ran; 1 honoured the contract we drafted; 6 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
6unverified

Licence: 0 of the 7 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 ppengtang/oicr. “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.

bbox_transform_inv ppengtang/oicr/lib/fast_rcnn/bbox_transform.py official repository ran · honoured contract fingerprinted MIT (permissive) · b3695ebe0c382b05 · report
bbox_transform ppengtang/oicr/lib/fast_rcnn/bbox_transform.py official repository unverified MIT (permissive) · 84dcf978d5570762 · report
clip_boxes ppengtang/oicr/lib/fast_rcnn/bbox_transform.py official repository unverified MIT (permissive) · d24c99284beca7a6 · report
get_imdb ppengtang/oicr/lib/datasets/factory.py official repository unverified MIT (permissive) · 9f3cea1708a8a9db · report
get_output_dir ppengtang/oicr/lib/fast_rcnn/config.py official repository unverified MIT (permissive) · b0dcfe8273d808a7 · report
im_list_to_blob ppengtang/oicr/lib/utils/blob.py official repository unverified MIT (permissive) · 015af0d600124541 · report
prep_im_for_blob ppengtang/oicr/lib/utils/blob.py official repository unverified MIT (permissive) · 9fa9d06d239312ea · report

Tasks

Multiple Instance LearningObjectObject DetectionObject RecognitionWeakly Supervised Object Detectionimage-classificationobject-detection

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Weakly Supervised Object Detection Charades PCL MAP 2.83 #2 of 6 Archive leaderboard report
Weakly Supervised Object Detection HICO-DET PCL MAP 3.62 #2 of 4 Archive leaderboard report
Weakly Supervised Object Detection ImageNet PCL-OB-G-Ens + FRCNN MAP 19.6 #1 of 4 Archive leaderboard report
Weakly Supervised Object Detection PASCAL VOC 2007 PCL-OB-G-Ens + FRCNN MAP 48.8 #22 of 41 Archive leaderboard report
Weakly Supervised Object Detection PASCAL VOC 2012 test PCL-OB-G-Ens + FRCNN MAP 44.2 #20 of 32 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

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