Visible to the public Biblio

Filters: Keyword is Histograms  [Clear All Filters]
2017-03-08
Lee, K., Kolsch, M..  2015.  Shot Boundary Detection with Graph Theory Using Keypoint Features and Color Histograms. 2015 IEEE Winter Conference on Applications of Computer Vision. :1177–1184.

The TRECVID report of 2010 [14] evaluated video shot boundary detectors as achieving "excellent performance on [hard] cuts and gradual transitions." Unfortunately, while re-evaluating the state of the art of the shot boundary detection, we found that they need to be improved because the characteristics of consumer-produced videos have changed significantly since the introduction of mobile gadgets, such as smartphones, tablets and outdoor activity purposed cameras, and video editing software has been evolving rapidly. In this paper, we evaluate the best-known approach on a contemporary, publicly accessible corpus, and present a method that achieves better performance, particularly on soft transitions. Our method combines color histograms with key point feature matching to extract comprehensive frame information. Two similarity metrics, one for individual frames and one for sets of frames, are defined based on graph cuts. These metrics are formed into temporal feature vectors on which a SVM is trained to perform the final segmentation. The evaluation on said "modern" corpus of relatively short videos yields a performance of 92% recall (at 89% precision) overall, compared to 69% (91%) of the best-known method.

Cook, B., Graceffo, S..  2015.  Semi-automated land/water segmentation of multi-spectral imagery. OCEANS 2015 - MTS/IEEE Washington. :1–7.

Segmentation of land and water regions is necessary in many applications involving analysis of remote sensing imagery. Not only is manual segmentation of these regions prone to considerable subjective variability, but the large volume of imagery collected by modern platforms makes manual segmentation extremely tedious to perform, particularly in applications that require frequent re-measurement. This paper examines a robust, semi-automated approach that utilizes simple and efficient machine learning algorithms to perform supervised classification of multi-spectral image data into land and water regions. By combining the four wavelength bands widely available in imaging platforms such as IKONOS, QuickBird, and GeoEye-1 with basic texture metrics, high quality segmentation can be achieved. An efficient workflow was created by constructing a Graphical User Interface (GUI) to these machine learning algorithms.

Liu, Weijian, Chen, Zeqi, Chen, Yunhua, Yao, Ruohe.  2015.  An \#8467;1/2-BTV regularization algorithm for super-resolution. 2015 4th International Conference on Computer Science and Network Technology (ICCSNT). 01:1274–1281.

In this paper, we propose a novelregularization term for super-resolution by combining a bilateral total variation (BTV) regularizer and a sparsity prior model on the image. The term is composed of the weighted least squares minimization and the bilateral filter proposed by Elad, but adding an ℓ1/2 regularizer. It is referred to as ℓ1/2-BTV. The proposed algorithm serves to restore image details more precisely and eliminate image noise more effectively by introducing the sparsity of the ℓ1/2 regularizer into the traditional bilateral total variation (BTV) regularizer. Experiments were conducted on both simulated and real image sequences. The results show that the proposed algorithm generates high-resolution images of better quality, as defined by both de-noising and edge-preservation metrics, than other methods.

2017-02-14
B. C. M. Cappers, J. J. van Wijk.  2015.  "SNAPS: Semantic network traffic analysis through projection and selection". 2015 IEEE Symposium on Visualization for Cyber Security (VizSec). :1-8.

Most network traffic analysis applications are designed to discover malicious activity by only relying on high-level flow-based message properties. However, to detect security breaches that are specifically designed to target one network (e.g., Advanced Persistent Threats), deep packet inspection and anomaly detection are indispensible. In this paper, we focus on how we can support experts in discovering whether anomalies at message level imply a security risk at network level. In SNAPS (Semantic Network traffic Analysis through Projection and Selection), we provide a bottom-up pixel-oriented approach for network traffic analysis where the expert starts with low-level anomalies and iteratively gains insight in higher level events through the creation of multiple selections of interest in parallel. The tight integration between visualization and machine learning enables the expert to iteratively refine anomaly scores, making the approach suitable for both post-traffic analysis and online monitoring tasks. To illustrate the effectiveness of this approach, we present example explorations on two real-world data sets for the detection and understanding of potential Advanced Persistent Threats in progress.

P. Das, S. C. Kushwaha, M. Chakraborty.  2015.  "Multiple embedding secret key image steganography using LSB substitution and Arnold Transform". 2015 2nd International Conference on Electronics and Communication Systems (ICECS). :845-849.

Cryptography and steganography are the two major fields available for data security. While cryptography is a technique in which the information is scrambled in an unintelligent gibberish fashion during transmission, steganography focuses on concealing the existence of the information. Combining both domains gives a higher level of security in which even if the use of covert channel is revealed, the true information will not be exposed. This paper focuses on concealing multiple secret images in a single 24-bit cover image using LSB substitution based image steganography. Each secret image is encrypted before hiding in the cover image using Arnold Transform. Results reveal that the proposed method successfully secures the high capacity data keeping the visual quality of transmitted image satisfactory.