Results 1 
8 of
8
Hidden digital watermarks in images
 IEEE Transaction on Image Processing
, 1998
"... Abstract — In this paper, an image authentication technique by embedding digital “watermarks ” into images is proposed. Watermarking is a technique for labeling digital pictures by hiding secret information into the images. Sophisticated watermark embedding is a potential method to discourage unauth ..."
Abstract

Cited by 91 (2 self)
 Add to MetaCart
(Show Context)
Abstract — In this paper, an image authentication technique by embedding digital “watermarks ” into images is proposed. Watermarking is a technique for labeling digital pictures by hiding secret information into the images. Sophisticated watermark embedding is a potential method to discourage unauthorized copying or attest the origin of the images. In our approach, we embed the watermarks with visually recognizable patterns into the images by selectively modifying the middlefrequency parts of the image. Several variations of the proposed method will be addressed. The experimental results show that the proposed technique successfully survives image processing operations, image cropping, and the Joint Photographic Experts Group (JPEG) lossy compression. Index Terms — Digital watermark, discrete cosine transform, JPEG compression, pseudorandom permutation. I.
Adaptive CMOS: From Biological Inspiration to SystemsonaChip
 PROCEEDINGS OF THE IEEE
, 2002
"... ..."
Mathematical Programming Algorithms for RegressionBased Nonlinear Filtering in R^N
 N ,” IEEE Transactions on Signal Processing
, 1999
"... This paper is concerned with regression under a "sum" of partial order constraints. Examples include locally monotonic, piecewise monotonic, runlength constrained, and unimodal and oligomodal regression. These are of interest not only in nonlinear filtering but also in density estimation a ..."
Abstract

Cited by 13 (2 self)
 Add to MetaCart
This paper is concerned with regression under a "sum" of partial order constraints. Examples include locally monotonic, piecewise monotonic, runlength constrained, and unimodal and oligomodal regression. These are of interest not only in nonlinear filtering but also in density estimation and chromatographic analysis. It is shown that under a least absolute error criterion, these problems can be transformed into appropriate finite problems, which can then be efficiently solved via dynamic programming techniques. Although the result does not carry over to least squares regression, hybrid programming algorithms can be developed to solve least squares counterparts of certain problems in the class. Index Terms Dynamic programming, locally monotonic, monotone regression, nonlinear filtering, oligomodal, piecewise monotonic, regression under order constraints, runlength constrained, unimodal. I.
Fast Digital Locally Monotonic Regression
, 1997
"... Locally monotonic regression is the optimal counterpart of iterated median filtering. In a previous paper, Restrepo and Bovik developed an elegant mathematical framework in which they studied locally monotonic regressions in R N . The drawback is that the complexity of their algorithms is exponen ..."
Abstract

Cited by 6 (1 self)
 Add to MetaCart
Locally monotonic regression is the optimal counterpart of iterated median filtering. In a previous paper, Restrepo and Bovik developed an elegant mathematical framework in which they studied locally monotonic regressions in R N . The drawback is that the complexity of their algorithms is exponential in N . In this paper, we consider digital locally monotonic regressions, in which the output symbols are drawn from a finite alphabet and, by making a connection to Viterbi decoding, provide a fast O(A² ffN ) algorithm that computes any such regression, where jAj is the size of the digital output alphabet, ff stands for lomo degree, and N is sample size. This is linear in N , and it renders the technique applicable in practice.
DHT domain digital watermarking with low loss in image informations
, 2008
"... The paper proposes a digital image watermarking scheme that selects regions for data embedding based on information measure. Two valued kernels of Hadamard transformation cause smaller image information change during embedding compared to other transform domains such as DCT (discrete cosine transfor ..."
Abstract
 Add to MetaCart
(Show Context)
The paper proposes a digital image watermarking scheme that selects regions for data embedding based on information measure. Two valued kernels of Hadamard transformation cause smaller image information change during embedding compared to other transform domains such as DCT (discrete cosine transform), DFT (discrete Fourier transform), Fourier–Mellin and waveletbased embedding. Moreover, the usage of Hadamard transform as signal decomposition tool offers advantages in terms of simpler implementation, low computation cost and high resiliency at low quality compression considering both JPEG and JPEG 2000 framework. Compression resiliency is further improved using adaptive negative modulation. These facts are validated comparing the performance with some other existing watermarking schemes as well as DCT domain implementation of the proposed scheme.
Efficient Coding for GMSK
, 1998
"... Coding for Gaussian Minimum Shift Keying is examined in AWGN channels. By combining a spectrally efficient modulation scheme with a standard code, the total bandwidth of the combined coding and modulation system can be made the same as an uncoded system. Using this approach, it is found that the ove ..."
Abstract
 Add to MetaCart
(Show Context)
Coding for Gaussian Minimum Shift Keying is examined in AWGN channels. By combining a spectrally efficient modulation scheme with a standard code, the total bandwidth of the combined coding and modulation system can be made the same as an uncoded system. Using this approach, it is found that the overall performance can be improved by approximately 3dB relative to an uncoded system with the same bandwidth. Keywords GMSK, error control coding 1 Introduction In virtually every communication system, error control coding is used to protect the transmitted information from external noise. The drawback of using coding is that for a fixed modulation scheme, the information rate is decreased. This can also be interpreted as an increase in the bandwidth required to transmit the data. In order to keep the bandwidth of a coded system the same as an uncoded system without decreasing the information rate, Trellis Coded Modulation (TCM) [1] schemes have been proposed and are used widely. TCM wo...
COPERM: TransformDomain Energy Compaction by Optimal Permutation
 IEEE Trans. Image Processing
, 1999
"... Compaction by optimal permutation (COPERM) is a tool for transformdomain energy compaction of broadband signals, whose foundation is a simple but powerful idea: Any signal can be transformed to resemble a more desirable (e.g., from a transformdomain compaction viewpoint) signal from a class of &qu ..."
Abstract
 Add to MetaCart
Compaction by optimal permutation (COPERM) is a tool for transformdomain energy compaction of broadband signals, whose foundation is a simple but powerful idea: Any signal can be transformed to resemble a more desirable (e.g., from a transformdomain compaction viewpoint) signal from a class of "target" signals (e.g., DCT basis functions) by means of a suitable permutation of its samples. One application of transformdomain energy compaction is in lossy compression. We pursue one possible thread in detail and demonstrate some interesting broadband image compression results. Index TermsBroadband image compression, coding, energy compaction, permutation, textures. I.
unknown title
"... Abstract — This paper presents a low power QPSK transmitter for MEDS band operating in 405406MHz frequency range with 10 channels, with 100KHz channel bandwidth. RF carrier is generated using an injection locked ring oscillator. A digitally controlled programmable charge pump is used for channel ..."
Abstract
 Add to MetaCart
(Show Context)
Abstract — This paper presents a low power QPSK transmitter for MEDS band operating in 405406MHz frequency range with 10 channels, with 100KHz channel bandwidth. RF carrier is generated using an injection locked ring oscillator. A digitally controlled programmable charge pump is used for channel selection. The four quadrant phase shift signals are generated by two RCCR phase shifters. The transmitter uses a Gilbert cell mixer for QPSK data modulation followed by a nonlinear class E power amplifier, as it is compatible with the constant envelope of the QPSK signal. The transmitter is designed in a UMC 130nm CMOS process with 1.2V power supply. Simulation shows that the proposed transmitter has 2.8mW total power dissipation for an output power of 250uW achieving 5.7 % EVM and it can modulate data rates up to