Image segmentation

Frame (networking)

Pattern recognition (psychology)

Expectation–maximization algorithm

Mathematics

Maximum likelihood

Statistics

Engineering

Pixel

Artificial intelligence

Markov random field

Dirt

Computer science

Computer vision

Mixture model

Telecommunications

Mechanical engineering

Segmentation

IEEE Transactions on Instrumentation and Measurement

Rail inspection system (RIS) remains an emergent instrumentation for railway transportation, with its capacity of measuring surface defect on steel rail. However, detecting technique and interpretation of RIS constitute a challenging problem since traditional technologies are expensive and prone to errors. In this paper, a deep multimodel RIS (DM-RIS) is established for surface defect where fast and robust spatially constrained Gaussian mixture model is presented for segmentation proposal and Faster RCNN is utilized for objective location in a parallel structure. First, we incorporate spatial information between pixels into an improved Gaussian mixture model based on Markov random field (MRF) for accurate and rapid defect edge segmentation. Specifically, a direct parameter-learning in expectation-maximization (EM) algorithm is proposed. Meanwhile, to remove nondefect, numerous labeled samples with weak illumination, inequality reflection, external noise, rust, and greasy dirt are fed into Faster RCNN so that DM-RIS is robust environmentally to various light, angle, background, and acquisition equipment. Finally, the joint hit area refers to a real defect. The experimental results demonstrate that the proposed method performs well with 96.74% precision, 94.13% recall, 95.18% overlap, and 0.485 s/frame speed on average, and is robust compared with the related well-established approaches.

DM-RIS: Deep Multimodel Rail Inspection System With Improved MRF-GMM and CNN