Co-PLNet: A Collaborative Point-Line Network for Prompt-Guided Wireframe Parsing
Chao Wang, Xuanying Li, Cheng Dai, Jinglei Feng, Yuxiang Luo, Yuqi Ouyang, Hao Qin
TL;DR
The paper tackles wireframe parsing, where accurate and consistent detection of line segments and junctions is essential for downstream SLAM. It introduces Co-PLNet, a collaborative framework that uses a Point-Line Prompt Encoder to generate spatial prompts from preliminary predictions and a Cross-Guidance Line Decoder that refines both lines and junctions via sparse attention. The main contributions are the point-line collaborative paradigm, prompt-based fusion of geometric cues, and an efficient attention mechanism that preserves real-time performance. Experiments on the Wireframe and YorkUrban datasets demonstrate competitive accuracy and robustness, achieving up to 76.8 FPS and showing that mutual prompts reduce endpoint mismatches and improve geometry consistency.
Abstract
Wireframe parsing aims to recover line segments and their junctions to form a structured geometric representation useful for downstream tasks such as Simultaneous Localization and Mapping (SLAM). Existing methods predict lines and junctions separately and reconcile them post-hoc, causing mismatches and reduced robustness. We present Co-PLNet, a point-line collaborative framework that exchanges spatial cues between the two tasks, where early detections are converted into spatial prompts via a Point-Line Prompt Encoder (PLP-Encoder), which encodes geometric attributes into compact and spatially aligned maps. A Cross-Guidance Line Decoder (CGL-Decoder) then refines predictions with sparse attention conditioned on complementary prompts, enforcing point-line consistency and efficiency. Experiments on Wireframe and YorkUrban show consistent improvements in accuracy and robustness, together with favorable real-time efficiency, demonstrating our effectiveness for structured geometry perception.
