From the Publisher: 
The accessible presentation of this book gives both a general view of the entire computer vision enterprise and also offers sufficient detail to be able to build useful applications. Users learn techniques that have proven to be useful by first-hand experience and a wide range of mathematical methods. A CD-ROM with every copy of the text contains source code for programming practice, color images, and illustrative movies. Comprehensive and up-to-date, this book includes essential topics that either reflect practical significance or are of theoretical importance. Topics are discussed in substantial and increasing depth. Application surveys describe numerous important application areas such as image based rendering and digital libraries. Many important algorithms broken down and illustrated in pseudo code. Appropriate for use by engineers as a comprehensive reference to the computer vision enterprise.

Computer vision : a modern approach = 计算机视觉 : 一种现代的方法

This paper presents a new reflectance model for rendering computer synthesized images. The model accounts for the relative brightness of different materials and light sources in the same scene. It describes the directional distribution of the reflected light and a color shift that occurs as the reflectance changes with incidence angle. The paper presents a method for obtaining the spectral energy distribution of the light reflected from an object made of a specific real material and discusses a procedure for accurately reproducing the color associated with the spectral energy distribution. The model is applied to the simulation of a metal and a plastic.

A reflectance model for computer graphics

An introduction to computer vision illumination and fixturing sensors image acquisition and representation fundamentals of digital image processing image analysis the segmentation problem 2-D shape description and recognition 3-D object representations robot programming and robot vision bin picking trends and aspirations.

Machine vision: automated visual inspection and robot vision

We investigate the feasibility of reconstructing an arbitrarily-shaped specular scene (refractive or mirror-like) from one or more viewpoints. By reducing shape recovery to the problem of reconstructing individual 3D light paths that cross the image plane, we obtain three key results. First, we show how to compute the depth map of a specular scene from a single viewpoint, when the scene redirects incoming light just once. Second, for scenes where incoming light undergoes two refractions or reflections, we show that three viewpoints are sufficient to enable reconstruction in the general case. Third, we show that it is impossible to reconstruct individual light paths when light is redirected more than twice. Our analysis assumes that, for every point on the image plane, we know at least one 3D point on its light path. This leads to reconstruction algorithms that rely on an "environment matting" procedure to establish pixel-to-point correspondences along a light path. Preliminary results for a variety of scenes (mirror, glass, etc.) are also presented.

/pdf/a-theory-of-refractive-and-specular-3d-shape-by-light-path-30yvkxm9c5.pdf

A Theory of Refractive and Specular 3D Shape by Light-Path Triangulation

High dynamic range fringe acquisition: A novel 3-D scanning technique for high-reflective surfaces

We describe a new laser rangefinder for measurement of the shapes of specular objects. In many industrial contexts, objects with both Lambertian surfaces and specular surfaces are often manipulated. However, ordinary laser rangefinders usually cannot be used to measure specular objects. We propose a laser rangefinder for the measurement of specular objects based on a new idea in which the incident angle of a light-stripe upon the image sensor is limited through the use of a special light device. The concept of this rangefinder involves the application of triangulation to specular objects, which enables measurement of the shape of specular objects as well as Lambertian objects. We designed and built a prototype light-stripe projection rangefinder based on these principles. Experiments using the rangefinder successfully demonstrate the rangefinder's accuracy. The proposed rangefinder is a promising tool for the performance of many common industrial tasks including measurement of the shapes of polished metal and the inspection of soldered joint surfaces.

New laser rangefinder for three-dimensional shape measurement of specular objects

The present paper describes a newly devised sensor which has the ability to detect the one-dimensional position and the one-dimensional angle of a light spot simultaneously. Ordinary laser-based measurement systems utilize a charge-coupled device or position sensitive device sensors. These conventional sensors can detect only a light spot's position. When the sensor can detect the incident angle of a light spot as well as the position, the sensor has a wide range of applicability. The sensor consists of two linear array-type sensors whose depth positions are slightly different. We have designed and built a prototype sensor system. We experimentally verified the practicable accuracy of the present sensor system. We also applied the present sensor system to two typical laser-based measurement systems: two-dimensional position measurement, and three-dimensional shape measurement for specular objects. Experimental results show that the sensor system was applicable to a laser-based measurement system.

A new sensor system for simultaneously detecting the position and incident angle of a light spot

This paper describes an analogue-based approach to fast subpixel-level edge detection. Although the most common subpixel edge detection methods employ digital-based approaches, they at present show certain drawbacks such as difficulty of fast, in-line subpixel edge detection, the necessity of implementing expensive high-resolution A/D converters, and difficulty in performing continuous, dynamic subpixel edge detection. We propose a new analogue-based first derivative subpixel edge detection approach to surmount these drawbacks. Our method involves the approximation of the distribution curve of the first derivative of the output of a CCD by using the second-order polynomial, and thus can accurately detect a peak position of the differential curve by means of the interpolating calculation, the operation of which is realized primarily through the use of analogue circuitry. The measurements of a concrete form using the prototype system demonstrate that its resolution under ideal conditions is about 1/10 pixels. We thus conclude that the approach described is effective for fast subpixel edge detection.

A fast edge location measurement with subpixel accuracy using a CCD image

The present paper describes a newly devised sensor, which has the ability to detect the two-dimensional position and the one-dimensional angle of a light spot simultaneously. Ordinary laser-based measurement systems utilize CCD or PSD sensors. These conventional sensors can detect only a light spot's position. When the sensor can detect the incident angle of a light spot as well as the position, the sensor has a wide range of applicability. The sensor consists of two linear array-type sensors whose depth positions are slightly different. We have designed and built a prototype sensor system. We experimentally verified the practicable accuracy of the present sensor system. We also applied the present sensor system to two typical laser-based measurement systems: 2-D position measurement, and 3-D shape measurement for specular objects. Experimental results show that the sensor system was applicable to a laser-based measurement system.

/pdf/a-new-sensor-system-for-simultaneously-detecting-the-370t9jr2p8.pdf

This paper describes an analogue-based approach to subpixel-level edge detection for dimension measurement and object localization. Although the most common subpixel edge detection methods employ digital-based approaches, at present they show certain drawbacks such as the difficulty of real-time, in-line subpixel edge detection, the necessity of implementing expensive high-resolution A/D converters, and difficulty in performing continuous, dynamic subpixel edge detection. These drawbacks present a difficult problem in digital-based systems industrial applications. We propose a new analogue-based first derivative subpixel edge detection approach to overcome these drawbacks. Our method involves the approximation of the distribution curve of the first derivative of the output of a CCD by using the second-order polynomial, and thus can accurately detect a peak position of the differential curve by means of the interpolating calculation, the operation of which is realized primarily through the use of analogue circuitry. The measurements of a concrete form using the prototype system demonstrate that its resolution under ideal conditions is about 1×10-1 pixels. While the resolution of this system decreases in an actual situation, the resolution remains at an acceptable subpixel level. We thereby conclude that the approach described in this paper is effective for real-time, low cost edge detection.

https://iopscience.iop.org/article/10.1088/1464-4258/3/4/308/pdf

Mitsuru Baba

Papers

New laser rangefinder for three-dimensional shape measurement of specular objects

A new sensor system for simultaneously detecting the position and incident angle of a light spot

A fast edge location measurement with subpixel accuracy using a CCD image

A new sensor system for simultaneously detecting the position and incident angle of a light spot

A novel subpixel edge detection system for dimension measurement and object localization using an analogue-based approach