Xiaodi Hou
California Institute of Technology, Computation and Neural Systems, Graduate Student
Abstract: Human labeled datasets, along with their corresponding evaluation algorithms, play an important role in boundary detection. We here present a psychophysical experiment that addresses the reliability of such benchmarks. To find... more
Abstract: Human labeled datasets, along with their corresponding evaluation algorithms, play an important role in boundary detection. We here present a psychophysical experiment that addresses the reliability of such benchmarks. To find better remedies to evaluate the performance of any boundary detection algorithm, we propose a computational framework to remove inappropriate human labels and estimate the intrinsic properties of boundaries.
In this paper, we present a novel approach to generate thumbnail images. Our method crops an image into a smaller but more informative region in the thumbnail representation. From the perspective of information theory, we propose a novel... more
In this paper, we present a novel approach to generate thumbnail images. Our method crops an image into a smaller but more informative region in the thumbnail representation. From the perspective of information theory, we propose a novel approach to generate bottom-up saliency in a global manner. In our method, we evaluate the statistical distribution of feature maps, and use its coding length as a measurement for image cropping. The experimental results offer viewers a more effective representation of images.
Abstract We introduce a simple image descriptor referred to as the image signature. We show, within the theoretical framework of sparse signal mixing, that this quantity spatially approximates the foreground of an image. We experimentally... more
Abstract We introduce a simple image descriptor referred to as the image signature. We show, within the theoretical framework of sparse signal mixing, that this quantity spatially approximates the foreground of an image. We experimentally investigate whether this approximate foreground overlaps with visually conspicuous image locations by developing a saliency algorithm based on the image signature.
What a human's eye tells a human's brain? In this paper, we analyze the information capacity of visual attention. Our hypothesis is that the limit of perceptible spatial frequency is related to observing time. Given more time, one can... more
What a human's eye tells a human's brain? In this paper, we analyze the information capacity of visual attention. Our hypothesis is that the limit of perceptible spatial frequency is related to observing time. Given more time, one can obtain higher resolution–that is, higher spatial frequency information, of the presented visual stimuli. We designed an experiment to simulate natural viewing conditions, in which time dependent characteristics of the attention can be evoked; and we recorded the temporal responses of 6 subjects.
Abstract A visual attention system should respond placidly when common stimuli are presented, while at the same time keep alert to anomalous visual inputs. In this paper, a dynamic visual attention model based on the rarity of features is... more
Abstract A visual attention system should respond placidly when common stimuli are presented, while at the same time keep alert to anomalous visual inputs. In this paper, a dynamic visual attention model based on the rarity of features is proposed. We introduce the Incremental Coding Length (ICL) to measure the perspective entropy gain of each feature. The objective of our model is to maximize the entropy of the sampled visual features.
Abstract In this paper, we propose a method to manipulate colors of an image. Based on a library of natural color images, our system evolves several prototypes of color distribution of the library, which we call" color concepts". By... more
Abstract In this paper, we propose a method to manipulate colors of an image. Based on a library of natural color images, our system evolves several prototypes of color distribution of the library, which we call" color concepts". By applying these color concepts on an input image, a user can easily change the mood of image colors in a global manner. Our results of photographs and paintings indicate that this method is capable of high-quality color manipulations.
Abstract The ability of human visual system to detect visual saliency is extraordinarily fast and reliable. However, computational modeling of this basic intelligent behavior still remains a challenge. This paper presents a simple method... more
Abstract The ability of human visual system to detect visual saliency is extraordinarily fast and reliable. However, computational modeling of this basic intelligent behavior still remains a challenge. This paper presents a simple method for the visual saliency detection. Our model is independent of features, categories, or other forms of prior knowledge of the objects.
Detecting moving objects against dynamic backgrounds remains a challenge in computer vision and robotics. This paper presents a surprisingly simple algorithm to detect objects in such conditions. Based on theoretic analysis, we show that... more
Detecting moving objects against dynamic backgrounds remains a challenge in computer vision and robotics. This paper presents a surprisingly simple algorithm to detect objects in such conditions. Based on theoretic analysis, we show that 1) the displacement of the foreground and the background can be represented by the phase change of Fourier spectra, and 2) the motion of background objects can be extracted by Phase Discrepancy in an efficient and robust way.