Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Ton Kalker is active.

Publication


Featured researches published by Ton Kalker.


signal processing systems | 2005

A Review of Audio Fingerprinting

Pedro Cano; Eloi Batlle; Ton Kalker; Jaap Haitsma

An audio fingerprint is a compact content-based signature that summarizes an audio recording. Audio Fingerprinting technologies have attracted attention since they allow the identification of audio independently of its format and without the need of meta-data or watermark embedding. Other uses of fingerprinting include: integrity verification, watermark support and content-based audio retrieval. The different approaches to fingerprinting have been described with different rationales and terminology: Pattern matching, Multimedia (Music) Information Retrieval or Cryptography (Robust Hashing). In this paper, we review different techniques describing its functional blocks as parts of a common, unified framework.


multimedia signal processing | 2002

A review of algorithms for audio fingerprinting

Pedro Cano; E. Batle; Ton Kalker; Jaap Haitsma

An audio fingerprint is a content-based compact signature that summarizes an audio recording. Audio fingerprinting technologies have recently attracted attention since they allow the monitoring of audio independently of its format and without the need of meta-data or watermark embedding. The different approaches to fingerprinting are usually described with different rationales and terminology depending on the background: pattern matching, multimedia (music) information retrieval or cryptography (robust hashing). In this paper, we review different techniques mapping functional parts to blocks of a unified framework.


IEEE Transactions on Information Forensics and Security | 2007

Reversible Image Watermarking Based on Integer-to-Integer Wavelet Transform

Sun-Il Lee; Chang D. Yoo; Ton Kalker

This paper proposes a high capacity reversible image watermarking scheme based on integer-to-integer wavelet transforms. The proposed scheme divides an input image into nonoverlapping blocks and embeds a watermark into the high-frequency wavelet coefficients of each block. The conditions to avoid both underflow and overflow in the spatial domain are derived for an arbitrary wavelet and block size. The payload to be embedded includes not only messages but also side information used to reconstruct the exact original image. To minimize the mean-squared distortion between the original and the watermarked images given a payload, the watermark is adaptively embedded into the image. The experimental results show that the proposed scheme achieves higher embedding capacity while maintaining distortion at a lower level than the existing reversible watermarking schemes.


Proceedings of the IEEE | 1999

Copy protection for DVD video

Jeffrey A. Bloom; Ingemar J. Cox; Ton Kalker; Jean-Paul M. G. Linnartz; Matthew L. Miller; C.B.S. Traw

The prospect of consumer digital versatile disk (DVD) recorders highlights the challenge of protecting copyrighted video content from piracy. We describe the copy-protection system currently under consideration for DVD. The copy-protection system broadly tries to prevent illicit copies from being made from either the analog or digital I/O channels of DVD recorders. An analog copy-protection system is utilized to protect the NTSC/PAL output channel by preventing copies to VHS. The digital transmission of content is protected by a robust encryption protocol between two communicating devices. Watermarking is used to encode copy-control information retrievable from both digital and analog signals. Hence, such embedded signals avoid the need for metadata to be carried in either the digital or analog domains. Finally, the copy-protection system provides the capability for one-generation copying. We discuss some proposed solutions and some of the implementation issues that are being addressed.


electronic imaging | 1999

Video watermarking system for broadcast monitoring

Ton Kalker; Geert Depovere; Jaap Haitsma; Maurice Maes

This paper presents a video watermarking technology for broadcast monitoring. The technology has been developed at the Philips Research Laboratories in Eindhoven in the context of the European ESPRIT project VIVA (Visual Identity Verification Auditor). The aim of the VIVA project is to investigate and demonstrate a professional broadcast surveillance system. The key technology in the VIVA project is a new video watermarking technique by the name of JAWS (Just Another Watermarking System). The JAWS system has been developed such that the embedded watermarks (1) are invisible, (2) are robust with respect to all common processing steps in the broadcast transmission chain, (3) have a very low probability of false alarms, (4) have a large payload at high rate, and (5) allow for a low complexity and a real-time detection. In this paper we present the basic ingredients of the JAWS technology. We also briefly discuss the performance of JAWS with respect to the requirements of broadcast monitoring.


Lecture Notes in Computer Science | 2002

Feature Extraction and a Database Strategy for Video Fingerprinting

Job C. Oostveen; Ton Kalker; Jaap Haitsma

This paper presents the concept of video fingerprinting as a tool for video identification. As such, video fingerprinting is an important tool for persistent identification as proposed in MPEG-21. Applications range from video monitoring on broadcast channels to filtering on peer-to-peer networks to meta-data restoration in large digital libraries. We present considerations and a technique for (i) extracting essential perceptual features from moving image sequences and (ii) for identifying any sufficiently long unknown video segment by efficiently matching the fingerprint of the short segment with a large database of pre-computed fingerprints.


international symposium on information theory | 2007

Signatures for Content Distribution with Network Coding

Fang Zhao; Ton Kalker; Muriel Médard; Keesook J. Han

Recent research has shown that network coding can be used in content distribution systems to improve the speed of downloads and the robustness of the systems. However, such systems are very vulnerable to attacks by malicious nodes, and we need to have a signature scheme that allows nodes to check the validity of a packet without decoding. In this paper, we propose such a signature scheme for network coding. Our scheme makes use of the linearity property of the packets in a coded system, and allows nodes to check the integrity of the packets received easily. We show that the proposed scheme is secure, and its overhead is negligible for large files.


Signal Processing-image Communication | 2004

A robust image fingerprinting system using the Radon transform

Jin S. Seo; Jaap Haitsma; Ton Kalker; Chang D. Yoo

With the ever-increasing use of multimedia contents through electronic commerce and on-line services, the problems associated with the protection of intellectual property, management of large database and indexation of content are becoming more prominent. Watermarking has been considered as efficient means to these problems. Although watermarking is a powerful tool, there are some issues with the use of it, such as the modification of the content and its security. With respect to this, identifying content itself based on its own features rather than watermarking can be an alternative solution to these problems. The aim of fingerprinting is to provide fast and reliable methods for content identification. In this paper, we present a new approach for image fingerprinting using the Radon transform to make the fingerprint robust against affine transformations. Since it is quite easy with modern computers to apply affine transformations to audio, image and video, there is an obvious necessity for affine transformation resilient fingerprinting. Experimental results show that the proposed fingerprints are highly robust against most signal processing transformations. Besides robustness, we also address other issues such as pairwise independence, database search efficiency and key dependence of the proposed method.


IEEE Signal Processing Magazine | 2000

Digital watermarking for DVD video copy protection

Maurice Maes; Ton Kalker; J.-P.M.G. Linnartz; J. Talstra; F.G. Depovere; J. Haitsma

We illustrate the various issues that play a role in designing a copy-protection system for digital versatile disk (DVD) video as perceived by Millennium, one of the two contenders in the DVD-video copy-protection standardization activity. We present the Millennium watermark system, the systems proposed for DVD video copy protection by Philips, Macrovision, and Digimarc. We also address some specific system aspects, such as watermark detector location and copy generation control.


electronic imaging | 2003

Capacity bounds and constructions for reversible data-hiding

Ton Kalker; Frans M. J. Willems

An undesirable side effect of many watermarking and data-hiding schemes is that the host signal into which auxiliary data is embedded is distorted. Finding an optimal balance between the amount of information embedded and the induced distortion is therefore an active field of research. In recent years, with the rediscovery of Costas seminal paper Writing on Dirty Paper, there has been considerable progress in understanding the fundamental limits of the capacity versus distortion of watermarking and data-hiding schemes. For some applications, however, no distortion resulting from auxiliary data, however small, is allowed. In these cases the use of reversible data-hiding methods provide a way out. A reversible data-hiding scheme is defined as a scheme that allows complete and blind restoration (i.e. without additional signaling) of the original host data. Practical reversible data-hiding schemes have been proposed by Fridrich et al., but little attention has been paid to the theoretical limits. Some first results on the capacity of reversible watermarking schemes have been derived. The reversible schemes considered in most previous papers have a highly fragile nature: in those schemes, changing a single bit in the watermarked data would prohibit recovery of both the original host signal as well as the embedded auxiliary data. It is the purpose of this paper to repair this situation and to provide some first results on the limits of robust reversible data-hiding. Admittedly, the examples provided in this paper are toy examples, but they are indicative of more practical schemes that will be presented in subsequent papers.

Collaboration


Dive into the Ton Kalker's collaboration.

Top Co-Authors

Avatar

Ingemar J. Cox

University College London

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge