Lightweight Indoor Modeling Based on Vertical Planes and Lines

Since vertical planes and lines are rich and unique for indoor localization, such as walls, posters, frames of doors and windows, a lightweight hybrid modeling method based on simple spatial features is proposed, specifically for the indoor localization and navigation applications. Firstly, the vertical planes in 3D space are detected and projected to generate a simplified floor plan of indoor environment. Here, a strategy of region segmentation and georeferencing is employed. Moreover, the plane-based model is further optimized by iterative merging algorithm. Then, some remarkable vertical lines are detected and localized based on the plane-based model, which can compensate the inaccuracy of plane ranges and the deficiency of remarkable planes in some areas. The dynamic time warping (DTW) algorithm is applied to match homonymous lines between sequential image frames, in cooperation with Kalman filtering for simultaneous tracking of vertical lines. Finally, a hybrid indoor model consisting of vertical planes and lines is generated, which is much more lightweight than previous 3D modeling methods. Experiments in real indoor scenes using single off-the-shelf smartphone verify the feasibility and effectiveness of the proposed method. The whole model size of an indoor environment with more than 200m² area is only 302 Bytes, and it achieves an accuracy of about 0.3 meters.