Wavelets for Object Representation and Recognition in Computer Vision

The paper descries a novel method to extract line segments and circular arcs from the image taken by CCD camera for object recognition. Model based matching is one of the widely used techniques of the object recognition in computer vision, and the position and orientation of the objects are decided with referring the extracted line segments and circular arcs. For the precise and stable decisions of the position and orientation, the accurate extractions of characters are required. These characters are. fast and accurately extracted in the proposed method, while its validity is confirmed in some experiments.

A survey of moment-based techniques for unoccluded object representation and recognition

In picture processing, picture segmentation, object classification and recognition is an impressive concept in present days because of increasing computer vision applications in real time applications. Based on required application, divide a picture into particular relevant clusters based on equivalent partitioning. Object identification is a minimum work to identify objects in a given picture or video with pixel values. The main representation of object classification from a given picture is to detect picture instances with respect to categorization of object. Object recognition is a complex task, when the pictures are poor quality, occlusion, and noise and in picture with background cutter sequences, this becomes more and efficient challenging task in picture processing. To appear object categorization and recognition effectively in pictures, there are several methods and approaches were introduced to solve object representation effectively. In this paper we review the different techniques of contextual feature extraction with respect to picture information of object classification, categorization and recognition of scalability and optimizations in real time picture processing applications. Our research gives better review of different approaches in picture categorization.

We address the problem of object recognition in computer vision. We represent each model and the scene in the form of Attributed Relational Graph. A multiple region representation is provided at each node of the scene ARG to increase the representation reliability. The process of matching the scene ARG against the stored models is facilitated by a novel method for identifying the most probable representation from among the multiple candidates. The scene and model graph matching is accomplished using probabilistic relaxation which has been modified to minimise the label clutter. The experimental results obtained on real data demonstrate promising performance of the proposed recognition system.

Depth learning has been applied in semantic segmentation and object recognition in computer vision. In this paper, we propose a high-efficiency pixel classification convolutional neural network based on encoder-decoder structure. Using depth image to enhance CNNS network make color image and depth information can be detected jointly. The experimental data shows that through the fusion of depth features representing different scales of information, the algorithm architecture can be jointly optimized and obtain more sophisticated image semantic features. Compared with similar methods, image semantic segmentation algorithm has obvious advantages.

Deep neural networks inspired by the connections among biological neurons have been highly effective in the advancement of computer vision. Recent research into recurrent neural networks has taken account of forward as well as recurrent connections in a neural network architecture. In this study, we proposed a model that mirrors the architecture of the human ventral pathway with separate layers representing brain regions connected using long-range recurrent links. CIFAR-10/100 datasets were used to assess the performance of object recognition using the proposed model and the results were compared with those obtained using state-of-the-art methods. We demonstrated that the classification accuracy increased as the number of recurrences increased. Our results suggest that the proposed neuroscience-inspired model can facilitate object recognition in computer vision and may help to elucidate neurological mechanisms in the human brain.

This study examines various algorithms for computing the convex hull of a set of n points in a d-dimensional space. Convex hulls are fundamental in computational geometry and are applied in computer graphics, pattern recognition, and computational biology. Such convex hulls can also be useful in symmetry problems. For instance, when points are arranged symmetrically, the convex hull is also likely to be symmetrically shaped, which can be useful for object recognition in computer vision or pattern recognition. The focus is primarily on two-dimensional algorithms, including well-known methods like Gift Wrapping, Graham Scan, Divide and Conquer, QuickHull, TORCH, Kirkpatrick–Sediel, and Chan’s algorithms. These algorithms vary in terms of time complexity and scalability to higher dimensions. This study is extended to three-dimensional convex hull algorithms, such as NAW, randomized insertion, and parallelized versions, such as CudaHull and CudaChain. This study aimed to elucidate the operational principles, step-by-step procedures, and comparative time complexities of each algorithm. The implementation in Python facilitates a detailed comparison of the algorithmic performance through stepwise analysis and graphical outputs. The ultimate goal is to provide insights into the strengths and weaknesses of each algorithm under various scenarios, thereby offering a comprehensive guide for practical implementation.

Hessian matrix is the square matrix of second partial derivatives of a scalar-valued function and is well known for object recognition in computer vision and medical shape analysis. Previous curvature based polyp detection algorithms generate myriad of false positives. Hessian-matrix based method, however, is more sensitive to local shape features, so easily reduce false positives. Calculation of Hessian matrix on 3D CT data and Eigen decomposition of the matrix gives three Eigen values and vectors at each voxel. Using these Eigen values, we can figure out which type of intensity structures (blob, line, and sheet-like) is on the given voxel. We focus on detecting blob-like object automatically. In the inner colonic wall structures, blob-like, line-like, and sheet-like objects represent polyps, folds and wall, respectively. In addition, to improve the performance of the algorithm, Gaussian blurring factor and shape threshold parameters are optimized. Before Hessian matrix calculation, smoothing the given region using Gaussian kernel with small deviation is necessary to enhance local intensity structures. To optimize the parameters and validate this method, we have produced anthropomorphic pig phantoms. Fourteen phantoms with 103 polyps (16 polyps <6mm, 87 >= 6mm) were used. CT scan was performed with 1mm slice thickness. Our detection algorithm found 84 polyps (81.6%) correctly. Average number of false positives is 7.9 at each CT scan. This results show that our algorithm is clinically applicable for polyp detection, because of high sensitivity and relatively low false positive detections.

Object Recognition has been a field in Computer Vision research, which is far from being solved when it comes to localizing the object of interest in an unconstrained environment, captured from different viewing angles. Lack of benchmark datasets clogs the progress in this field since the last decade, barring the subset of a single dataset, alias the Office dataset, which attempted to boost research in the field of pose-invariant detection and recognition of portable object in unconstrained environment. A new challenging object dataset with 30 categories has been proposed with a vision to boost the performances of the task of object recognition for portable objects, thus enhancing the study of cross domain adaptation, in conjunction to the Office dataset. Images of various hand-held objects are captured by the primary camera of a smartphone, where they are photographed under unconstrained environment with varied illumination conditions at different viewing angles. The monte-carlo object detection and recognition has been performed for the proposed dataset, facilitated by existing state-of-the-art transfer learning techniques for cross-domain recognition of objects. The baseline accuracies for existing Domain Adaptation methods, published recently, are also presented in this paper, for the kind perusal of the researchers. A new technique has also been proposed based on the activation maps of the AlexNet to detect objects, alongwith a Generative Adversarial Network (GAN) based Domain Adaptation technique for Object Recognition.

The role of invariant line junctions in object and visual word recognition

PurposeArtificial intelligence-enabled techniques can process large amounts of surgical data and may be utilized for clinical decision support to recognize or forecast adverse events in an actual intraoperative scenario. To develop an image-guided navigation technology that will help in surgical education, we explored the performance of a convolutional neural network (CNN)-based computer vision system in detecting intraoperative objects.MethodsThe surgical videos used for annotation were recorded during surgeries conducted in the Department of Surgery of Tokyo Women’s Medical University from 2019 to 2020. Abdominal endoscopic images were cut out from manually captured surgical videos. An open-source programming framework for CNN was used to design a model that could recognize and segment objects in real time through IBM Visual Insights. The model was used to detect the GI tract, blood, vessels, uterus, forceps, ports, gauze and clips in the surgical images.ResultsThe accuracy, precision and recall of the model were 83%, 80% and 92%, respectively. The mean average precision (mAP), the calculated mean of the precision for each object, was 91%. Among surgical tools, the highest recall and precision of 96.3% and 97.9%, respectively, were achieved for forceps. Among the anatomical structures, the highest recall and precision of 92.9% and 91.3%, respectively, were achieved for the GI tract.ConclusionThe proposed model could detect objects in operative images with high accuracy, highlighting the possibility of using AI-based object recognition techniques for intraoperative navigation. Real-time object recognition will play a major role in navigation surgery and surgical education.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11548-021-02434-w.

The field of computer vision has undergone rapid development. Starting from recognition tasks such as classification, detection, and segmentation, the focus of visual analysis has gradually shifted towards learning spatiotemporal information. This thesis presents research on spatiotemporal learning, with a particular emphasis on motion estimation and visual recognition. First, we address the problem of video object tracking. Previous methods have primarily re-lied on learning improved appearance representations, while the spatiotemporal relationships of individual objects have been underexplored. We propose leveraging optical flow features to achieve higher generalization in semi-supervised video object segmentation, directly incorporating these features into both the target representation and the decoder network. Our experiments and analysis show that enriching feature representations with spatiotemporal information improves segmentation quality and generalization capability. Next, we investigate spatiotemporal learning in 3D for motion estimation, specifically scene flow estimation. Scene flow estimation as an important research topic in 3D computer vision is crucial for applications such as robotics, autonomous driving, embodied navigation, and tracking. We investigate the problem in different perspectives: 1. What is the best formulation for solving the problem and how to learn a better spatiotemporal feature representation? 2. Can we introduce uncertainty estimation to the task, which is of crucial importance for safety-critical downstream tasks? 3. How to scale the estimation to large-scale data, e.g., autonomous scenes, and leverage the temporal information without introducing much computation overheads? To answer these questions, we explore the use of transformers for improved feature representation, diffusion models for uncertainty estimation, and efficient feature learning methods for multi-frame, large-scale autonomous driving scenarios. Finally, we extend our research to joint visual segmentation, tracking, and open-vocabulary recognition in LiDAR sequences, particularly for autonomous scenes. In such environments, precise segmentation, tracking, and recognition of objects are essential for downstream analysis and control. Current human-annotated open-source datasets allow for reasonable tracking of traffic participants such as cars and pedestrians. However, we aim to advance beyond this towards segmenting and tracking any object in LiDAR data. To this end, we propose a pseudo-labeling engine that leverages the 2D visual foundation model SAM v2 and the vision-language model CLIP to automatically label LiDAR streams. We further introduce the SAL-4D model, capable of segmenting, tracking, and recognizing any object in a zero-shot manner. In summary, we explore the learning of spatiotemporal information in both 2D image and 3D point cloud domains. In the image domain, we demonstrate that spatiotemporal information improves video object segmentation quality and generalization. In the 3D point cloud domain, we show that spatiotemporal learning enables more accurate motion estimation and facilitates the first method for zero-shot segmentation, tracking, and open-vocabulary recognition of arbitrary objects.

The problem of tracking people using multiple cameras is of much current interest as a means of providing cues for audio-visual blind source separation in dynamic environments. Here we investigate the use of one of the current state-of-the-art techniques in object recognition combined with one of the most popular methods of modelling object motion, particle filters, for tracking people. The dictionary learning or Bag-of-Words approach to object recognition has proved to be very effective in recent years, as shown in a number of large comparisons such as the PASCAL Visual Object recognition Challenge (VOC). In this paper we use this proven object recognition method within the framework of a particle filter. This provides a more accurate and robust tracking of people in a multiple camera environment. We also demonstrate that the dictionary learning approach can provide a principled method for the fusion of multiple features.

To perform daily activities is a very difficult task for visually impaired people, since vision plays a central role in almost every activity of ours. With the advancement in computer vision and computing technologies we can afford to develop a system for visually impaired people, which can give audio feedback of surrounding objects and context. In this paper a novel assistive method for visually impaired people using object and color recognition is proposed, which is very useful for their safety, quality life and freedom from the other person all the time. The system is containing two modules (i) object recognition, (ii) color recognition. Object recognition module recognizes objects like door, chair, stairs, mobile phone etc. and generate an audio feedback to the user, we are using convolution neural network prior to recursive neural network which is followed by softmax classifier. Second module of this system is color recognition which tell them about object color in front of the camera, this module is useful in recognizing clothing colors, fruits color, police(from uniform color) etc. We are using HSI color space with observed thresholding for color recognition. System modules and operation can be selected with an on demand push button panel. The algorithm is evaluated on an online dataset as well as on our dataset.

Object recognition is of fundamental importance in computer vision. In a few years, pedestrian detection, car detection, and more generally scene recognition will likely be reliable enough to allow fully-automated car navigation, and the human driver will be relegated to the back seat to sip his coffee. In this thesis we are interested in recognizing individual objects and categories. In order to reduce the volume of information one has to process, images are characterized by sets of features. These features, also called interest points, are targeted at image locations with high local information content. Various systems for detecting interest points and for describing the local image appearance near these points, have been proposed in the last two decades. We investigate which combinations from this plethora of detectors and descriptors, are most suited for object recognition tasks. On to the problem of object recognition, we are first interested in recognizing individual objects. In a few years, one can imagine that customers in shops, will take with their cell phone a picture of a product that looks interesting, send it to a remote server with a huge database of individual objects, and get back information about that specific product. We propose a system for individual object recognition, inspired from previous work on coarse-to-fine recognition. All steps of the recognition process are translated into principled probabilistic terms, which allows us to outperform a state-of-the-art commercial system for individual recognition. Regarding categories, faces are probably the category that has received the most attention in computer vision literature. Here we propose a system to recognize images of the same individual in large databases of images. This can be of high interest when looking for images of a given person over the internet. Our method's advantage is that it works on real-world images, as opposed to the face databases from the literature, collected in laboratories with controlled lighting, pose and background conditions. Finally, we are interested in recognition of object categories in general. Using support vector machines for the classification task, we propose a features-based kernel that improves recognition performance on object categories.