Dense multiview stereo based on image texture enhancement

This work reports on convolutional neural network (CNN) performance on an image texture classification task as a function of linear image processing and number of training images. Detection performance of single and multi-layer CNNs (sCNN/mCNN) are compared to optimal observers. Performance is quantified by the area under the receiver operating characteristic (ROC) curve, also known as the AUC. For perfect detection AUC = 1.0 and AUC = 0.5 for guessing. The Ideal Observer (IO) maximizes AUC but is prohibitive in practice because it depends on high-dimensional image likelihoods. The IO performance is invariant to any fullrank, invertible linear image processing. This work demonstrates the existence of full-rank, invertible linear transforms that can degrade both sCNN and mCNN even in the limit of large quantities of training data. A subsequent invertible linear transform changes the images’ correlation structure again and can improve this AUC. Stationary textures sampled from zero mean and unequal covariance Gaussian distributions allow closed-form analytic expressions for the IO and optimal linear compression. Linear compression is a mitigation technique for high-dimension low sample size (HDLSS) applications. By definition, compression strictly decreases or maintains IO detection performance. For small quantities of training data, linear image compression prior to the sCNN architecture can increase AUC from 0.56 to 0.93. Results indicate an optimal compression ratio for CNN based on task difficulty, compression method, and number of training images.

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Research on college gymnastics teaching model based on multimedia image and image texture feature analysis

Discover Internet of Things ◽

10.1007/s43926-021-00015-6 ◽

2021 ◽

Vol 1 (1) ◽

Author(s):

Ying Wu ◽

Jikun Liu

Keyword(s):

Human Body ◽

Rapid Development ◽

Texture Feature ◽

Texture Features ◽

Dynamics Simulation ◽

Image Texture ◽

Whole Body ◽

Database Modeling ◽

Rigid Model ◽

The Subject

AbstractWith the rapid development of gymnastics technology, novel movements are also emerging. Due to the emergence of various complicated new movements, higher requirements are put forward for college gymnastics teaching. Therefore, it is necessary to combine the multimedia simulation technology to construct the human body rigid model and combine the image texture features to display the simulation image in texture form. In the study, GeBOD morphological database modeling was used to provide the data needed for the modeling of the whole-body human body of the joint and used for dynamics simulation. Simultaneously, in order to analyze and summarize the technical essentials of the innovative action, this experiment compared and analyzed the hem stage of the cross-headstand movement of the subject and the hem stage of the 180° movement. Research shows that the method proposed in this paper has certain practical effects.

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PatchMatch based Multiview Stereo with Local Quadric Window

Proceedings of the 28th ACM International Conference on Multimedia ◽

10.1145/3394171.3413966 ◽

2020 ◽

Author(s):

Hyewon Song ◽

Jaeseong Park ◽

Suwoong Heo ◽

Jiwoo Kang ◽

Sanghoon Lee

Keyword(s):

Multiview Stereo

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An Evaluation of the Effectiveness of Image-based Texture Features Extracted from Static B-mode Ultrasound Images in Distinguishing between Benign and Malignant Ovarian Masses

Ultrasonic Imaging ◽

10.1177/0161734621998091 ◽

2021 ◽

pp. 016173462199809

Author(s):

Dhurgham Al-karawi ◽

Hisham Al-Assam ◽

Hongbo Du ◽

Ahmad Sayasneh ◽

Chiara Landolfo ◽

...

Keyword(s):

Gabor Filter ◽

Empirical Evaluation ◽

Texture Features ◽

Image Texture ◽

Support Vector ◽

Simple Majority ◽

Ultrasound Scan ◽

Histograms Of Oriented Gradients ◽

The Individual ◽

Ovarian Masses

Significant successes in machine learning approaches to image analysis for various applications have energized strong interest in automated diagnostic support systems for medical images. The evolving in-depth understanding of the way carcinogenesis changes the texture of cellular networks of a mass/tumor has been informing such diagnostics systems with use of more suitable image texture features and their extraction methods. Several texture features have been recently applied in discriminating malignant and benign ovarian masses by analysing B-mode images from ultrasound scan of the ovary with different levels of performance. However, comparative performance evaluation of these reported features using common sets of clinically approved images is lacking. This paper presents an empirical evaluation of seven commonly used texture features (histograms, moments of histogram, local binary patterns [256-bin and 59-bin], histograms of oriented gradients, fractal dimensions, and Gabor filter), using a collection of 242 ultrasound scan images of ovarian masses of various pathological characteristics. The evaluation examines not only the effectiveness of classification schemes based on the individual texture features but also the effectiveness of various combinations of these schemes using the simple majority-rule decision level fusion. Trained support vector machine classifiers on the individual texture features without any specific pre-processing, achieve levels of accuracy between 75% and 85% where the seven moments and the 256-bin LBP are at the lower end while the Gabor filter is at the upper end. Combining the classification results of the top k ( k = 3, 5, 7) best performing features further improve the overall accuracy to a level between 86% and 90%. These evaluation results demonstrate that each of the investigated image-based texture features provides informative support in distinguishing benign or malignant ovarian masses.

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