A Contrario Line Segment Detection by Rafael Grompone von Gioi

By Rafael Grompone von Gioi

The trustworthy detection of low-level photo buildings is an previous and nonetheless not easy challenge in machine imaginative and prescient. This booklet leads a close travel throughout the LSD set of rules, a line section detector designed to be absolutely automated. in keeping with the a contrario framework, the set of rules works successfully with no the necessity of any parameter tuning. The layout standards are completely defined and the algorithm's solid and undesirable effects are illustrated on actual and artificial photographs. the problems concerned, in addition to the suggestions used, are universal to many geometrical constitution detection difficulties and a few attainable extensions are discussed.

Show description

Read or Download A Contrario Line Segment Detection PDF

Best computer vision & pattern recognition books

Advances in Geometric Modeling and Processing: 6th International Conference, GMP 2010, Castro Urdiales, Spain, June 16-18, 2010, Proceedings

This publication constitutes the refereed complaints of the sixth foreign convention on Geometric Modeling and Processing, GMP 2010, held in Castro Urdiales, Spain, in June 2010. The 20 revised complete papers provided have been rigorously reviewed and chosen from a complete of 30 submissions. The papers hide a large spectrum within the quarter of geometric modeling and processing and deal with themes equivalent to recommendations of transcendental equations; quantity parameterization; delicate curves and surfaces; isogeometric research; implicit surfaces; and computational geometry.

Discrete Geometry for Computer Imagery: 15th IAPR International Conference, DGCI 2009, Montréal, Canada, September 30 - October 2, 2009, Proceedings

This publication constitutes the refereed lawsuits of the fifteenth IAPR foreign convention on Discrete Geometry for machine Imagery, DGCI 2009, held in Montr? al, Canada, in September/October 2009. The forty two revised complete papers have been conscientiously reviewed and chosen from various submissions. The papers are prepared in topical sections on discrete form, illustration, reputation and research; discrete and combinatorial instruments for picture segmentation and research; discrete and combinatorial Topology; versions for discrete geometry; geometric transforms; and discrete tomography.

Independent Component Analysis of Edge Information for Face Recognition

The ebook provides examine paintings on face acceptance utilizing side details as positive factors for face popularity with ICA algorithms. The self sufficient elements are extracted from facet info. those self reliant parts are used with classifiers to check the facial photographs for attractiveness goal. of their examine, authors have explored Canny and LOG side detectors as normal side detection tools.

Advanced Technologies in Ad Hoc and Sensor Networks: Proceedings of the 7th China Conference on Wireless Sensor Networks

Complicated applied sciences in advert Hoc and Sensor Networks collects chosen papers from the seventh China convention on instant Sensor Networks (CWSN2013) held in Qingdao, October 17-19, 2013. The e-book positive factors cutting-edge stories on Sensor Networks in China with the topic of “Advances in instant sensor networks of China”.

Additional info for A Contrario Line Segment Detection

Example text

The multisegment detector makes erroneous cuts in line segments and some slanted ones Chapter 3 The LSD Algorithm This chapter describes in full detail the LSD algorithm [31, 35, 36] for line segment detection. It is based on the a contrario framework described in the previous chapter, but instead of searching exhaustively for line segments, it uses the heuristic search plus validation approach, resulting in an efficient algorithm. The source code and an online demo for LSD are available at [36].

8. Finally, the validation step follows the same ideas described in Sect. 2. According to Definition 2, the pixels in the rectangle whose level-line angles correspond to the angle of the rectangle up to a tolerance τ are called aligned pixels. The total number of pixels in the rectangle, n, and its number of aligned pixels, k, are counted and used to validate or not the rectangle as a detected line segment, see Fig. 3. The heuristic method solves two problems at the same time. First, it makes the algorithm fast, being able to compute the result in linear time relative to the number of pixels, see Sects.

This is a slight overestimation, but what is relevant is the order of magnitude. LSD uses a multi-precision p approach as described in Sect. 4. Then, the number γ of different p values also needs to be included in the number of tests. Finally, Ntests = (NM)5/2 γ . Given an image x and a candidate rectangle r, the number of aligned pixels will be denoted by k(r, x), while n(r) is the total number of pixels in r. NFA(r, x) = Ntests · P[k(r, X) ≥ k(r, x)] , 40 3 The LSD Algorithm where X is a random image following H0 .

Download PDF sample

Rated 4.70 of 5 – based on 32 votes

Related posts