Publications associées à Modified discrete cosine transform

Practical Multiple-Scattering Sheen Using Linearly Transformed Cosines

We introduce a new volumetric sheen BRDF that approximates scattering observed in surfaces covered with normally-oriented fibers. Our previous sheen model was motivated by measured cloth reflectance, but lacked significant backward scattering. The model pr ...

ASSOC COMPUTING MACHINERY2022

Function Integration, Reconstruction And Approximation Using Rank-1 Lattices

Fabio Nobile, Giovanni Migliorati

We consider rank-1 lattices for integration and reconstruction of functions with series expansion supported on a finite index set. We explore the connection between the periodic Fourier space and the non-periodic cosine space and Chebyshev space, via tent ...

2021

Single shot acquisition of spatially resolved spin wave dispersion relations using X-ray microscopy

Dirk Grundler

For understanding magnonic materials the fundamental characterization of their frequency response is essential. However, determining full dispersion relations and real space wavelength measurements are challenging and time-consuming tasks. We present an ap ...

Nature Research2020

Practical Product Path Guiding Using Linearly Transformed Cosines

Wenzel Alban Jakob

Path tracing is now the standard method used to generate realistic imagery in many domains, e.g., film, special effects, architecture etc. Path guiding has recently emerged as a powerful strategy to counter the notoriously long computation times required t ...

WILEY2020

Discrete Time Analysis of Phase Detector Timing Nonidealities in Type-I Sub-Sampling PLL

Yusuf Leblebici, Duygu Kostak

The analysis of the effect of sub-sampling phase detector (SSPD) timing nonidealities on Type-I sub-sampling phase-locked loop (SSPLL) is presented. The nonidealities considered are the delay between the complementary sampling clocks and the propagation de ...

IEEE2020

Feature integration within discrete time windows

Michael Herzog, Adrien Christophe Doerig, Leila Drissi Daoudi - Kleinbauer

Sensory information must be integrated over time to perceive, for example, motion and melodies. Here, to study temporal integration, we used the sequential metacontrast paradigm in which two expanding streams of lines are presented. When a line in one stre ...

Nature Research2019

An Approach to Increase the Bandwidth of Current Controllers for Grid-tied Converters with LCL Filter

Francisco Daniel Freijedo Fernández

This This article discusses the design of a current controller for a converter system connected to the electrical grid through a LCL filter. A form of compensation is proposed and implemented to mitigate the effects of the computational delay in the discre ...

IEEE2019

MULAN: A Blind and Off-Grid Method for Multichannel Echo Retrieval

Rémi Gribonval, Helena Peic Tukuljac

This paper addresses the general problem of blind echo retrieval, i.e., given M sensors measuring in the discrete-time domain M mixtures of K delayed and attenuated copies of an unknown source signal, can the echo locations and weights be recovered? This p ...

2018

Gold Raspberry-Like Colloidosomes Prepared at the Water-Nitromethane Interface

Hubert Girault, Evgeny Smirnov, Pekka Eero Peljo

Here, we propose a simple shake-flask method to produce micron-size colloidosomes from a liquid-liquid interface functionalized with a gold nanoparticle film. A step-by-step extraction process of an organic phase partially miscible with water led to the fo ...

2018

Method for estimating synchrophasors during static and dynamic conditions

Mario Paolone, Asja Derviskadic, Paolo Romano

A method for performing synchrophasor estimation of an input signal, whereby the input signal is a sinusoidal power system voltage or current signal, comprising: a. Periodic sampling of a continuous time-domain waveform, consisting of a power system voltag ...

2018

Spatiotemporal feature integration within discrete time windows provides evidence for discrete perception

Michael Herzog, Adrien Christophe Doerig, Leila Drissi Daoudi - Kleinbauer

Intuitively, consciousness seems to be a continuous stream of percepts. Here, contrary to intuition, we show evidence for discrete consciousness, occurring only at certain moments of time. We presented a Vernier followed by a sequence of flanking lines on ...

2018

Design and Applications of Approximate Circuits by Gate-Level Pruning

Christian Enz, Vincent Frédéric Camus, Jérémy Lucien Maurice Schlachter

Energy-efficiency is a critical concern for many systems, ranging from Internet of things objects and mobile devices to high-performance computers. Moreover, after 40 years of prosperity, Moore's law is starting to show its economic and technical limits. N ...

Ieee-Inst Electrical Electronics Engineers Inc2017

Optimal Representations of Sparse Stochastic Processes with Applications in Image Processing

Pedram Pad

We establish in the world of stochastic processes a theoretical relation between sparsity and wavelets. The underlying principle is to treat stochastic processes as generalized functions, which facilitates the study of their properties in a transform domai ...

EPFL2017

MRI artifact correction using sparse plus low-rank decomposition of annihilating filter-based hankel matrix

Kyong Hwan Jin

PurposeMagnetic resonance imaging (MRI) artifacts are originated from various sources including instability of an magnetic resonance (MR) system, patient motion, inhomogeneities of gradient fields, and so on. Such MRI artifacts are usually considered as ir ...

Wiley2017

Design of Energy-Efficient Discrete Cosine Transform using Pruned Arithmetic Circuits

Christian Enz, Vincent Frédéric Camus, Jérémy Lucien Maurice Schlachter

Inexact circuits and approximate computing have been gaining a lot of interest in order to improve performances and energy efficiency beyond the boundaries of conventional digital circuits. Image and video processing is one of the best candidate for applyi ...

IEEE2016

Optimality of Operator-Like Wavelets for Representing Sparse AR(1) Processes

Michaël Unser, Pedram Pad

The discrete cosine transform (DCT) is known to be asymptotically equivalent to the Karhunen-Loève transform (KLT) of Gaussian first-order auto-regressive (AR(1)) processes. Since being uncorrelated under the Gaussian hypothesis is synonymous with independ ...

IEEE2015

Optimized Kaiser-Bessel Window Functions for Computed Tomography

Michaël Unser, Cédric René Jean Vonesch, John Paul Ward, Masih Nilchian

Kaiser-Bessel window functions are frequently used to discretize tomographic problems because they have two desirable properties: 1) their short support leads to a low computational cost and 2) their rotational symmetry makes their imaging transform indepe ...

Ieee-Inst Electrical Electronics Engineers Inc2015

Multiple phase estimation via signal separation using a windowed Fourier transform in digital holographic interferometry

Pramod Rastogi, Rishikesh Dilip Kulkarni

This paper proposes a novel method for the simultaneous estimation of multiple interference phases from a single recording of the interference field in a multi-wave digital holographic interferometry set-up. The method involves the separation of signal com ...

Institute of Physics2015

Jaggies as aliasing or reconstruction phenomena: a tutorial

Roger Hersch, Isaac Amidror

Jaggies (staircasing effects) along slanted lines or curved edges are omnipresent in digital imaging. They are so widespread in digital display devices that very often they are associated with the modern "computerized" world (and sometimes even intentional ...

Is&T & Spie2014

On The Optimality Of Operator-Like Wavelets For Sparse Ar(1) Processes

Michaël Unser, Pedram Pad

Sinusoidal transforms such as the DCT are known to be optimal-that is, asymptotically equivalent to the Karhunen-Loeve transform (KLT)-for the representation of Gaussian stationary processes, including the classical AR(1) processes. While the KLT remains a ...

Ieee2013