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Information of the urban road areas for resource management, security monitoring, urban development and Geographic Information System (GIS) is changing with the growing world. Satellite image provides useful data that is extracted from satellite image of the urban area. Automatic extraction of the road intersections from the urban areas has been a challenging topic because the high resolution satellite...
In this paper we propose a watermarking technique in the spatial domain using gray images. Algorithms based on modulo operations are developed to embed the watermark into the host image. Number of bits embedded in a pixel is determined by the degree of modulo algorithm being used. The size of the watermark is stored in the last few pixels as overhead bits. Extraction of data is done using the same...
This paper presents insights gained from applying biological vision mechanisms in the context of computer vision algorithm design, implementation and initial evaluation. In this paper a software-based space variant log(z) retina tessellation is used to sample the underlying image, maintaining the high resolution at the central foveal region and an increasingly sparse sampling density at the surrounding...
In this paper, a new method for extracting edges in images is proposed. The local pixel values are normalized to make their sum become unity. Then, a nonlinear filtering process is applied to the normalized pixel values by using the sine or cosine function. Two new edge detection operators, which exploit the local convexity of the sine and cosine functions, are thus defined. The edges are detected...
This paper presents a high DR, high temporal resolution, frame-free image/video camera that encodes and processes visual information in asynchronous spikes. The event-driven optical sensor features 9.3-bit grayscale imaging at up to 143dB DR and <;0.25% FPN with hardware-based lossless video compression and time-domain correlated double sampling. The main components of the camera - the asynchronous,...
Multiplicative speckle noise is always present in synthetic aperture sonar (SAS) images, which is due to the coherent nature of scattering phenomena. Many methods that reduce speckle noise while preserving texture and detail have been developed for SAR and presented in the literature. In this paper, some speckle reduction techniques from SAR images are adapted and applied to SAS high resolution images...
Generally hiding information destroys the host image, however, some sensitive images for which any embedding distortion of the image is intolerable, such as military images, medical images, or artwork preservation etc. Reversible data hiding techniques are designed to solve the problem of Lossless embedding of large messages in digital images so that after the embedded message is extracted, the image...
3D scene rendering requires depth maps and color information to produce high quality 3D results. Unfortunately, depth maps captured with the Time-of-flight (TOF) cameras have limited resolution and poor image quality, being severely influenced by the random and systematic noise, which makes them inapposite for generating high quality 3D images. In this paper, we have further analyzed a framework for...
High-definition (HD) and super-high-definition (SHD) videos become more and more popular for various video applications, including video capture and playback on portable devices. Because of the resolution mismatch between HD/SHD video and the low resolution screen of portable devices, the video is fully decoded and then sown-sampled for the display, which causes a waste of both computational power...
Iris recognition is widely regarded as one of the most unique methods for subject identification. The practical application of iris recognition is primarily limited by constraints imposed on subjects to enable the collection of images of sufficient quality for recognition. This paper introduces the Iris-at-a-Distance (IAAD) system. The IAAD system is a prototype that illustrates the feasibility of...
In this paper, memory reduction method using the Sub-PFP is proposed. That is, two-dimensional PFPs in conventional N-LUT method can be converted by one-dimensional Sub-PFPs using trigonometric relations. Some experiments with a test 3-D object are carried out and the reduction ratio of LUT is analyzed.
In novel look-up table (N-LUT) method, the size of LUT is determined by the amount of shift of the principle fringe pattern (PFP). Thus, if the resolution of object is increased or pixel pitch of hologram is decreased, the size of LUT is increased. Therefore, in this paper, we propose the memory reduction method using the relation of pixel pitch of hologram and reconstruction distance. Some experiments...
In this work, we propose novel image descriptors for identifying head poses in low resolution images. The key novelty of our method is to exploit two types of non-local metric for estimating head poses: non-local intensity difference feature (iDF) and non-local color difference feature (cDF). Unlike the existing methods that one pixel can only represent one head pose information, our proposed features...
RGB color signals encoding is more desirable for high resolution and accurate definition for saturations and hue. This paper presents a region adaptive inter-color prediction scheme for 4:4:4 RGB signals, which treats G component as a primary component and predicts B/R component from G component with different weighting factors based on different texture regions. The proposed algorithm demonstrates...
Super-resolution involves the use of signal processing techniques to estimate the high-resolution (HR) version of a scene from multiple low-resolution (LR) observations. It follows that the quality of the reconstructed HR image would depend on the quality of the LR observations. The latter depends on multiple factors like the image acquisition process, encoding or compression and transmission. However,...
In this paper, we propose a 3DTV system supporting delivery of full HD resolution 3DTV contents over HFC network. So far, we have used a 3DTV system supporting only frame-compatible format of 3DTV contents in order to provide 3DTV broadcasting service over HFC network. Using the frame-compatible format has an advantage being compatible with the current digital cable broadcasting system when transmitting...
Recently a novel look-up table (N-LUT) method to dramatically reduce the number of pre-calculated interference patterns required for generation of digital holograms was proposed. In this method, principle fringe pattern (PFP) has reflection symmetry in geometry. Thus in this paper, we proposed the memory reduction method using this reflection symmetry of PFP. From some experimental result, the memory...
In this paper, a new approach for fast computation of CGH patterns for the 3-D image by combined use of the DPCM and the N-LUT is proposed. Some experiments with test 3-D images are carried out and the results are compared to those of the conventional methods in terms of the number of the object points and computation time.
In this study, a novel split method was proposed to enlarge low resolution image. Instead of maintaining the grey levels of original pixels and estimating the grey levels for newly added pixels, the proposed approach split the original pixel, into new pixels. Two approaches are proposed to estimate grey levels for the new pixels, namely zero order split approach and 2nd order split approach. Degraded...
Image segmentation is critical to image processing and pattern recognition, An image segmentation system is proposed for the segmentation of color image based on neural networks. First, we introduce BP Neural network, it has the capacity of parallel computing, distributed saving, self-studying, fault-to-learnt and nonlinear function approximating. So it widely used in image segmentation, but it also...
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