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You searched for subject:(error surface modeling). Showing records 1 – 3 of 3 total matches.

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University of Southern California

1. Zhang, Qi. Advanced techniques for high fidelity video coding.

Degree: PhD, Electrical Engineering, 2010, University of Southern California

This research focuses on two advanced techniques for high-bit-rate video coding: 1) subpel motion estimation and 2) residual processing.; First, we study sup-pixel motion estimation for video coding. We analyze the characteristics of the sub-pel motion estimation error surface and propose an optimal subpel motion vector resolution estimation scheme that allows each block with different characteristics to maximize its RD gain through a flexible motion vector resolution. Furthermore, a direct subpel MV prediction scheme is proposed to estimate the optimal subpel position. The rate-distortion performance of the proposed motion prediction scheme is close to that of full search while it demands only about of 10% of the computational complexity of the full search.; Secondly, we investigate high-bit-rate video coding techniques for high definition video contents. We observed that under the requirements of high-bit-rate coding, there still left a large portion of uncompensated information in the prediction residual that represents similar signal characteristics of film grain noise. Due to small quantization step size used by high-bit-rate coding, these untreated small features render all existing coding schemes ineffective. To address this issue, a novel granular noise prediction and coding scheme is proposed to provide a separate treatment for these residuals. A frequency domain-based prediction and coding scheme is proposed to enhance the coding performance. The proposed granular noise prediction and coding scheme outperforms H.264/AVC by an average of 10% bit rate saving.; Thirdly, we further investigate on the impact of high-bit-rate coding from the more fundamental signal characteristics point of view. A probability distribution analysis on DCT coefficients from the H.264/AVC codec under different bit rates is conducted to reveal that the prediction residual in the form of DCT coefficients have a near uniform distribution for all scanning positions. To further understand this phenomenon, a correlation based analysis was conducted to show that the different types of correlations existed in the video frame and the distribution of these correlations highly impact the coding efficiency. A significant amount of short and medium-range correlations due to the use of a fine quantization parameter cannot be easily removed by existing compensation techniques. Consequently, the video coding performance degrades rapidly as quality increases. A novel Multi-Order-Residual (MOR) coding scheme was proposed. The concept is based on the numerical analysis to extract different correlation through different phases. A different DCT-based compensation and coding scheme combined with an improved rate-distortion optimization process was proposed to target the higher-order signal characteristics. An additional pre-search coefficient optimization phase was proposed to further enhance compression performance. Experimental results show that the proposed MOR scheme outperforms H.264/AVC by an average of 16% bit rate savings. Advisors/Committee Members: Kuo, C.-C. Jay (Committee Chair), Ortega, Antonio (Committee Member), Shahabi, Cyrus (Committee Member).

Subjects/Keywords: subpixel motion search; complexity; error surface modeling; fast motion estimation; motion vector prediction; multi-order residual; MOR

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Zhang, Q. (2010). Advanced techniques for high fidelity video coding. (Doctoral Dissertation). University of Southern California. Retrieved from http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll127/id/352557/rec/550

Chicago Manual of Style (16th Edition):

Zhang, Qi. “Advanced techniques for high fidelity video coding.” 2010. Doctoral Dissertation, University of Southern California. Accessed December 11, 2019. http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll127/id/352557/rec/550.

MLA Handbook (7th Edition):

Zhang, Qi. “Advanced techniques for high fidelity video coding.” 2010. Web. 11 Dec 2019.

Vancouver:

Zhang Q. Advanced techniques for high fidelity video coding. [Internet] [Doctoral dissertation]. University of Southern California; 2010. [cited 2019 Dec 11]. Available from: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll127/id/352557/rec/550.

Council of Science Editors:

Zhang Q. Advanced techniques for high fidelity video coding. [Doctoral Dissertation]. University of Southern California; 2010. Available from: http://digitallibrary.usc.edu/cdm/compoundobject/collection/p15799coll127/id/352557/rec/550


Carnegie Mellon University

2. Garland, Michael. Quadric-Based Polygonal Surface Simplification.

Degree: 1999, Carnegie Mellon University

Many applications in computer graphics and related fields can benefit fromautomatic simplification of complex polygonal surface models. Applications areoften confronted with either very densely over-sampled surfaces or models toocomplex for the limited available hardware capacity. An effective algorithmfor rapidly producing high-quality approximations of the original model is avaluable tool for managing data complexity. In this dissertation, I present my simplification algorithm, based on iterativevertex pair contraction. This technique provides an effective compromisebetween the fastest algorithms, which often produce poor quality results, andthe highest-quality algorithms, which are generally very slow. For example, a1000 face approximation of a 100,000 face model can be produced in about 10seconds on a PentiumPro 200. The algorithm can simplify both the geometryand topology of manifold as well as non-manifold surfaces. In addition toproducing single approximations, my algorithm can also be used to generatemultiresolution representations such as progressive meshes and vertex hierarchiesfor view-dependent refinement. The foundation of my simplification algorithm, is the quadric error metricwhich I have developed. It provides a useful and economical characterization oflocal surface shape, and I have proven a direct mathematical connection betweenthe quadric metric and surface curvature. A generalized form of this metric canaccommodate surfaces with material properties, such as RGB color or texturecoordinates. I have also developed a closely related technique for constructing a hierarchyof well-defined surface regions composed of disjoint sets of faces. This algorithminvolves applying a dual form of my simplification algorithm to the dual graphof the input surface. The resulting structure is a hierarchy of face clusters whichis an effective multiresolution representation for applications such as radiosity.

Subjects/Keywords: surface simplification; multiresolution modeling; level of detail; edge contraction; quadric error metric

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Garland, M. (1999). Quadric-Based Polygonal Surface Simplification. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/282

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Garland, Michael. “Quadric-Based Polygonal Surface Simplification.” 1999. Thesis, Carnegie Mellon University. Accessed December 11, 2019. http://repository.cmu.edu/dissertations/282.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Garland, Michael. “Quadric-Based Polygonal Surface Simplification.” 1999. Web. 11 Dec 2019.

Vancouver:

Garland M. Quadric-Based Polygonal Surface Simplification. [Internet] [Thesis]. Carnegie Mellon University; 1999. [cited 2019 Dec 11]. Available from: http://repository.cmu.edu/dissertations/282.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Garland M. Quadric-Based Polygonal Surface Simplification. [Thesis]. Carnegie Mellon University; 1999. Available from: http://repository.cmu.edu/dissertations/282

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


North Carolina State University

3. Cai, Hubo. Accuracy Evaluation of a 3-D Spatial Modeling Approach to Model Linear Objects and Predict Their Lengths.

Degree: PhD, Civil Engineering, 2004, North Carolina State University

Real world objects are three-dimensional. Numerous applications in geographic information systems (GISs) require modeling spatial objects in a 3-D space, but many current GISs only represent two-dimensional information. The GIS community has been struggling with solving complex problems dealing with 3-D objects using a 2-D approach. This research focused on modeling linear objects in a 3-D space, predicting their 3-D distances, and evaluating the accuracy. A point model was developed, which modeled a 3-D line with a group of 3-D points (with X/Y/Z-coordinates) connected by straight lines. It required two input datasets, an elevation dataset and a planimetric line dataset. With elevation datasets in different formats (point data and digital elevation models (DEMs)), two approaches were proposed, differing in how the third dimension (elevation) was introduced. With point data, a snapping approach was developed. With DEMs, elevations for points uniformly distributed along planimetric lines were obtained via bilinear interpolations. Mathematical equations were derived to predict 3-D distances. A case study was designed in the transportation field because of the rich source of linear objects and the criticality of 3-D distances in GIS-T and LRS. Two elevation datasets were used: LIDAR and national elevation dataset (NED). LIDAR datasets were further categorized into point data and DEMs (20-ft and 50-ft resolutions). Two intervals were taken to locate points planimetrically along lines when using DEMs (full cell size and half cell size). Consequently, each line was associated with seven calculated 3-D distances (one from LIDAR point data, two from LIDAR 20-ft DEM, two from LIDAR 50-ft DEM, and two from NED). The accuracy of predicted 3-D distances was evaluated by comparing them to distance measurement instrument (DMI) measured distances. Errors were represented in two formats: difference and proportional difference (based on DMI measured distances) between the predicted 3-D distance and the DMI measured distance, taking road types into consideration. Evaluation methods included descriptive statistics, error distribution histograms, hypothesis tests, frequency analysis, and root mean square of errors (RMSE). The effects from the use of different elevation datasets and intervals on the accuracy were evaluated via a sensitivity analysis. The effects from the geometric properties of linear objects on the accuracy were evaluated via significant factor analyses. Factors under consideration included distance, average slope and weighted slope, average slope change and weighted slope change, and the number and density of 3-D points. The usefulness of this research was proved by applying the resulting 3-D road centerlines to determine flooded road segments under flooding scenarios. This research concluded that errors in the predicted 3-D distance varied with elevation datasets and road types, but not with the use of different intervals with the same elevation dataset, given the interval was less than or equal… Advisors/Committee Members: Joseph E. Hummer, Committee Member (advisor), Hugh A. Devine, Committee Member (advisor), Heather M. Cheshire, Committee Member (advisor), William J. Rasdorf, Committee Chair (advisor).

Subjects/Keywords: GIS; Frequency Analysis; 3-D Modeling; Floodplain Delineation; Error Propagation; Error; Spatial Data Accuracy; Snapping; Sensitivity Analysis; DMI; Distance Prediction; DEM; Data Quality; Breakline; ANOVA; Accuracy; LIDAR; GIS-T; GPS; NED; RMSE; Road Centerline; LIDAR Point Clouds; Surface Length

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Cai, H. (2004). Accuracy Evaluation of a 3-D Spatial Modeling Approach to Model Linear Objects and Predict Their Lengths. (Doctoral Dissertation). North Carolina State University. Retrieved from http://www.lib.ncsu.edu/resolver/1840.16/5556

Chicago Manual of Style (16th Edition):

Cai, Hubo. “Accuracy Evaluation of a 3-D Spatial Modeling Approach to Model Linear Objects and Predict Their Lengths.” 2004. Doctoral Dissertation, North Carolina State University. Accessed December 11, 2019. http://www.lib.ncsu.edu/resolver/1840.16/5556.

MLA Handbook (7th Edition):

Cai, Hubo. “Accuracy Evaluation of a 3-D Spatial Modeling Approach to Model Linear Objects and Predict Their Lengths.” 2004. Web. 11 Dec 2019.

Vancouver:

Cai H. Accuracy Evaluation of a 3-D Spatial Modeling Approach to Model Linear Objects and Predict Their Lengths. [Internet] [Doctoral dissertation]. North Carolina State University; 2004. [cited 2019 Dec 11]. Available from: http://www.lib.ncsu.edu/resolver/1840.16/5556.

Council of Science Editors:

Cai H. Accuracy Evaluation of a 3-D Spatial Modeling Approach to Model Linear Objects and Predict Their Lengths. [Doctoral Dissertation]. North Carolina State University; 2004. Available from: http://www.lib.ncsu.edu/resolver/1840.16/5556

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