A Parallel Histogram-based Particle Filter for Object Tracking on SIMD-based Smart Cameras

We present a parallel implementation of a histogram-based particle filter for object tracking on smart cameras based on SIMD processors. We specifically focus on parallel computation of the particle weights and parallel construction of the feature histograms since these are the major bottlenecks in standard implementations of histogram-based particle filters. The proposed algorithm can be applied with any histogram-based feature sets—we show in detail how the parallel particle filter can employ simple color histograms as well as more complex histograms of oriented gradients (HOG). The algorithm was successfully implemented on an SIMD processor and performs robust object tracking at up to 30 frames per second—a performance difficult to achieve even on a modern desktop computer

Subobject Detection through Spatial Relationships on Mobile Phones

We present a novel image classification technique for detecting multiple objects (called subobjects) in a single image. In addition to image classifiers, we apply spatial relationships among the subobjects to verify and to predict locations of detected and undetected subobjects, respectively. By continuously refining the spatial relationships throughout the detection process, even locations of completely occluded exhibits can be determined. Finally, all detected subobjects are labeled and the user can select the object of interest for retrieving corresponding multimedia information. This approach is applied in the context of PhoneGuide, an adaptive museum guidance system for camera-equipped mobile phones. We show that the recognition of subobjects using spatial relationships is up to 68% faster than related approaches without spatial relationships. Results of a field experiment in a local museum illustrate that unexperienced users reach an average recognition rate for subobjects of 85.6% under realistic conditions

Embedded Real Time Gesture Tracking

Video tracking is the process of locating a moving object (or several ones) in time using a camera. An algorithm evaluates the video frames and outputs the location of moving targets within the video frame

Dynamically reconfigurable architecture for embedded computer vision systems

The objective of this research work is to design, develop and implement a new architecture which integrates on the same chip all the processing levels of a complete Computer Vision system, so that the execution is efficient without compromising the power consumption while keeping a reduced cost. For this purpose, an analysis and classification of different mathematical operations and algorithms commonly used in Computer Vision are carried out, as well as a in-depth review of the image processing capabilities of current-generation hardware devices. This permits to determine the requirements and the key aspects for an efficient architecture. A representative set of algorithms is employed as benchmark to evaluate the proposed architecture, which is implemented on an FPGA-based system-on-chip. Finally, the prototype is compared to other related approaches in order to determine its advantages and weaknesses

Performance Analysis of Tracking on Mobile Devices using Local Binary Descriptors

With the growing ubiquity of mobile devices, users are turning to their smartphones and tablets to perform more complex tasks than ever before. Performing computer vision tasks on mobile devices must be done despite the constraints on CPU performance, memory, and power consumption. One such task for mobile devices involves object tracking, an important area of computer vision. The computational complexity of tracking algorithms makes them ideal candidates for optimization on mobile platforms. This thesis presents a mobile implementation for real time object tracking. Currently few tracking approaches take into consideration the resource constraints on mobile devices. Optimizing performance for mobile devices can result in better and more efficient tracking approaches for mobile applications such as augmented reality. These performance benefits aim to increase the frame rate at which an object is tracked and reduce power consumption during tracking. For this thesis, we utilize binary descriptors, such as Binary Robust Independent Elementary Features (BRIEF), Oriented FAST and Rotated BRIEF (ORB), Binary Robust Invariant Scalable Keypoints (BRISK), and Fast Retina Keypoint (FREAK). The tracking performance of these descriptors is benchmarked on mobile devices. We consider an object tracking approach based on a dictionary of templates that involves generating keypoints of a detected object and candidate regions in subsequent frames. Descriptor matching, between candidate regions in a new frame and a dictionary of templates, identifies the location of the tracked object. These comparisons are often computationally intensive and require a great deal of memory and processing time. Google\u27s Android operating system is used to implement the tracking application on a Samsung Galaxy series phone and tablet. Control of the Android camera is largely done through OpenCV\u27s Android SDK. Power consumption is measured using the PowerTutor Android application. Other performance characteristics, such as processing time, are gathered using the Dalvik Debug Monitor Server (DDMS) tool included in the Android SDK. These metrics are used to evaluate the tracker\u27s performance on mobile devices