3D Shape description algorithms applied to the problem of model retrieval

2011 ◽  
Vol 1 (1) ◽  
Author(s):  
Dariusz Frejlichowski
Keyword(s):  
Three Dimensional ◽  
3D Models ◽  
Multimedia Data ◽  
Computer Hardware ◽  
Shape Description ◽  
3D Shape ◽  
Retrieval Result ◽  
Dimensional Shape ◽  
Image Shape ◽  
Three Dimensional Shape

AbstractInterest in three-dimensional shape retrieval is currently increasing, driven by two important reasons — the rapid increase of the amount of multimedia data and a noticeable advance in computer hardware and software during recent years. Presently, it is possible to retrieve complicated 3D models in a reasonable span of time thanks to the use of sophisticated 3D shape description algorithms, a feat which was unthinkable a few years ago. The main issue is the efficiency of the approaches, which must work both quickly and reliably. Hence, in this paper four 3D shape description algorithms — Extended Gaussian Image, Shape Distributions, Shape Histograms and Light Field Descriptor — were experimentally compared in order to determine which was most effective. As it turned out, the latter obtained the best retrieval result.

High Resolution "DIY" Photogrammetry - 'HRP' Protocol v1

2021 ◽  
Author(s):  
Yu Tang ◽  
Jacopo Niccolo Cerasoni ◽  
Emily Yuko Hallett
Keyword(s):  
High Resolution ◽  
Computer Graphic ◽  
Three Dimensional ◽  
3D Models ◽  
High Accuracy ◽  
Dimensional Shape ◽  
Short Time ◽  
Three Dimensional Shape

Photogrammetry is a method of calculating the three-dimensional shape of an object from a set of images. The advantages of Photogrammetry include the ability to record the shape of an object in a short time and with high accuracy without contact. In addition, the generated model can be displayed without textures. Here, the High Resolution Photogrammetry method is presented, which describes the use of photogrammetric techniques to take pictures and generate models. This method aims to give a comprehensive and extensive description for the development of high resolution 3D models, merging the well known techniques used in academic and computer graphic fields, allowing anyone to independently produce high resolution and quantifiable models for any need.

Three-dimensional shape measurement based on binary fringe conventional projection

2019 ◽  
Vol 41 (14) ◽  
pp. 4073-4083 ◽  
Author(s):  
Guangkai Fu ◽  
Yiping Cao ◽  
Yapin Wang ◽  
Yingying Wan ◽  
Lu Wang ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Shape Measurement ◽  
Measured Object ◽  
3D Shape ◽  
Phase Measuring Profilometry ◽  
3D Shape Measurement ◽  
Large Step ◽  
Dimensional Shape ◽  
Three Dimensional Shape ◽  
Error Suppression

A three-dimensional (3D) shape measurement method based on binary fringe conventional projection is proposed. In traditional 3D shape measurement methods based on binary fringe projection, the binary fringe is used as an approximate sinusoidal fringe by defocusing projection or even directly used as an approximate sinusoidal fringe by nonlinear error suppression feature of large-step phase measuring profilometry (PMP). In the proposed method (Prop), neither defocusing projection is needed nor large-step PMP must be used. When the binary fringe is conventionally projected on the measured object, just by filtering operation in spatial frequency domain from the captured deformed pattern, the nearly unbroken sinusoidal deformed pattern can be extracted efficiently. While N ( N≥3) frames binary fringes with 1/ N period misalignment between each adjacent fringe are conventionally projected onto the measured object sequentially, the corresponding nearly unbroken N-step sinusoidal deformed patterns extracted from the N frames captured deformed patterns can be used to reconstruct the 3D shape of the measured object with N-step PMP algorithm. The experimental results show the feasibility and validity of the Prop. It is more flexible for its optional fringe period and optional phase-shifting steps. It has potential application in the real-time 3D shape measurement.

An Engineering Shape Benchmark for 3D Models

2005 ◽  
Author(s):  
Natraj Iyer ◽  
Subramaniam Jayanti ◽  
Karthik Ramani
Keyword(s):  
Mechanical Engineering ◽  
Large Body ◽  
Three Dimensional ◽  
3D Models ◽  
Shape Representations ◽  
Benchmark Database ◽  
Dimensional Shape ◽  
Work Done ◽  
Three Dimensional Shape ◽  
Shape Searching

Three dimensional shape searching is a problem of current interest in several different fields, especially in the mechanical engineering domain. There has been a large body of work in developing representations for 3D shapes. However, there has been limited work done in developing domain dependent benchmark databases for 3D shape searching. In this paper, we propose a benchmark database for evaluating shape based search methods relevant to the mechanical engineering domain. Twelve feature vector based representations are compared using the benchmark database. The main contributions of this paper are development of an engineering shape benchmark and an understanding of the effectiveness of different shape representations for classes of engineering parts.

scholarly journals A Description of Three-Dimensional Shape of the Posterior Torso Comparing Those with and without Scoliosis

Symmetry ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 211 ◽  
Author(s):  
Adrian Gardner ◽  
Fiona Berryman ◽  
Paul Pynsent
Keyword(s):  
Three Dimensional ◽  
Procrustes Analysis ◽  
3D Analysis ◽  
3D Shape ◽  
3D Elements ◽  
Dimensional Shape ◽  
The Mean ◽  
The Difference ◽  
The Right ◽  
Three Dimensional Shape

Scoliosis results in a 3D asymmetry of the spine and torso. It is not clear what the variability in 3D shape is in a non-scoliotic population, how much that is altered by scoliosis and what surgery does to that. This study is a 3D analysis of the shape of the torso in a cohort of non-scoliotic children that is then compared with a cohort of those with scoliosis both pre- and post-operatively. Procrustes analysis is used to examine the mean 3D shape. There is variability in shape in the non-scoliotic cohort. Scoliosis increases this asymmetry, particularly around the most prominent areas of the torso. Surgery alters the torso asymmetry but increases the difference in height between the right and the left with regard to the most prominent points on the torso. There is a degree of asymmetry seen in a non-scoliotic cohort of children. Scoliosis increases that asymmetry. Surgery alters the asymmetry but causes an increase in some of the 3D elements of the most prominent areas of the torso.

Three-Dimensional Shape and Fall Velocity Measurements of Snowflakes Using a Multiangle Snowflake Imager

2017 ◽  
Vol 34 (8) ◽  
pp. 1763-1781 ◽  
Author(s):  
Haruya Minda ◽  
Norio Tsuda ◽  
Yasushi Fujiyoshi
Keyword(s):  
Three Dimensional ◽  
Shape Reconstruction ◽  
Velocity Measurements ◽  
Particle Size Distributions ◽  
Fall Velocity ◽  
Silhouette Width ◽  
3D Shape ◽  
3D Shape Reconstruction ◽  
Dimensional Shape ◽  
Three Dimensional Shape

AbstractThis paper describes a Multiangle Snowflake Imager (MSI) designed to capture the pseudo-three-dimensional (3D) shape and the fall velocity of individual snowflakes larger than 1.5 mm in size. Four height-offset line-image scanners estimate fall velocities and the four-angle silhouettes are used to reconstruct the 3D snowflake shapes. The 3D shape reconstruction is tested using reference objects (spheres, spheroids, cubes, and plates). The four-silhouette method of the MSI improves the representation of the particle shape and volume compared to two-silhouette methods, such as the two-dimensional video disdrometer (2DVD). The volume (equivolumetric diameters) of snowflakes estimated by the four-silhouette method is approximately 44% (13%) smaller than that estimated by the two-silhouette method. The ability of the imager to measure the fall velocity and particle size distributions based on the silhouette width and the equivolumetric diameter of 3D-shaped particles is verified via a comparison with the 2DVD in three snowfall events.

Four Dimensions of Diamond T: Combination Trade Marks of Colours And Shapes

2006 ◽  
Vol 37 (4) ◽  
pp. 583
Author(s):  
Michael McGowan
Keyword(s):  
Three Dimensional ◽  
Trade Mark ◽  
Fourth Dimension ◽  
Trade Marks ◽  
Four Dimensions ◽  
Trade Mark Law ◽  
Dimensional Shape ◽  
Three Dimensional Shape

This article examines the relatively new fields of colour and shape trade marks. It was initially feared by some academics that the new marks would encroach on the realms of patent and copyright.  However, the traditional requirements of trade mark law, such as functionality and descriptiveness, have meant that trade marks in colour and shape are extremely hard to acquire if they do not have factual distinctiveness. As colour and shape trade marks have no special restrictions, it is proposed that the combination trade mark theory and analysis from the Diamond T case should be used as a way to make them more accessible. The combination analysis can be easily applied because every product has a three dimensional shape and a fourth dimension of colour.

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