Color balance | EPFL Graph Search

In photography and , color balance is the global adjustment of the intensities of the colors (typically red, green, and blue primary colors). An important goal of this adjustment is to render specific colors – particularly neutral colors like white or grey – correctly. Hence, the general method is sometimes called gray balance, neutral balance, or white balance. Color balance changes the overall mixture of colors in an image and is used for color correction. Generalized versions of color balance are used to correct colors other than neutrals or to deliberately change them for effect. White balance is one of the most common kinds of balancing, and is when colors are adjusted to make a white object (such as a piece of paper or a wall) appear white and not a shade of any other colour. Image data acquired by sensors – either film or electronic s – must be transformed from the acquired values to new values that are appropriate for color reproduction or display. Several aspects of the

Fair Voice Biometrics: Impact of Demographic Imbalance on Group Fairness in Speaker Recognition

Mirko Marras

Speaker recognition systems are playing a key role in modern online applications. Though the susceptibility of these systems to discrimination according to group fairness metrics has been recently studied, their assessment has been mainly focused on the difference in equal error rate across groups, not accounting for other fairness criteria important in anti-discrimination policies, defined for demographic groups characterized by sensitive attributes. In this paper, we therefore study how existing group fairness metrics relate with the balancing settings of the training data set in speaker recognition. We conduct this analysis by operationalizing several definitions of fairness and monitoring them under varied data balancing settings. Experiments performed on three deep neural architectures, evaluated on a data set including gender/age-based groups, show that balancing group representation positively impacts on fairness and that the friction across security, usability, and fairness depends on the fairness metric and the recognition threshold.

ISCA-INT SPEECH COMMUNICATION ASSOC2021

Microcamera Embedded in a Wristwatch

Michael Ansorge, Pierre-André Farine, Patrick Stadelmann, Steve Tanner

The presentation reports upon the conception and realization of a miniature very low-power microcamera system that has been embedded in a wristwatch so as to enable the spontaneous capture of photographs in everyday life based on timekeeping devices the users would naturally wear. The designed microcamera system is fully operational and incorporates specific optics and a color VGA format based image sensor, a viewfinder enabling the selection of the scene to be captured, an image preprocessing step for color interpolation and white/color balance, followed by a dedicated JPEG compatible still image compression algorithm producing fixed-sized encoded images. Finally, the user is given the possibility to screen a posteriori (postview mode) the set of images captured, e.g. to erase less interesting ones in order to liberate the corresponding storage space. The user interface is composed of a particular display usually indicating the time, that is switching into a camera management mode for the acquisition and postview of photographs. Moreover, the camera can communicate with a personal computer through a cradle either to download the set of photographs acquired, or to upload a set of operational parameters, while simultaneously reloading the accumulator supplying the microcamera of the wristwatch. The technological challenge induced by the dense integration requirement of the numerous peripheral devices, including the central processing capabilities, the user and communication interfaces, and the tight power consumption constraints to be fulfilled, ask for the elaboration of numerous innovative solutions out of which only few were published so far. The purpose of the presentation is to provide insight into the system organization and its breakdown into original inter-playing hardware and software components, which were finally validated by the realization of an industrial prototype and demonstrator. The multi-fold experience collected by the partners in the design proce- ss is of course nurturing further activities, and, from a didactic viewpoint, offered the opportunity to set up practical laboratories that were dispensed in the realm of the Summer Schools Highlights in Microtechnology coordinated by the European Associated Laboratory (LEA) and more recently funded by the EU FP6 Marie Curie programme.

2007

Sulfur-bearing lipids for the covalent attachment of supported lipid bilayers to gold surfaces: a detailed characterization and analysis

Jacques Dubochet, Claus Duschl, Martha Liley, Henning Paul-Julius Stahlberg, Horst Vogel, Shaik Mohammed Zakeeruddin

In a recent paper, a new class of synthetic lipids, which self-assemble to form monolayers on gold surfaces, was introduced. The addn. of a monolayer of phospholipids to these layers results in robust supported lipid bilayers designed to reconstitute transmembrane proteins. This paper presents a detailed characterization of the monolayers and bilayers formed by these lipids and assesses their ability for the incorporation of membrane-spanning proteins. Film balance methods, electron microscopy, surface plasmon resonance, Fourier transform IR measurements and Raman spectroscopy show the feasibility of this concept. However, further modifications to improve the thiolipids are necessary. A new strategy for the formation of laterally structured supported lipid bilayers is discussed and initial results are presented. [on SciFinder (R)]

1996

Microcamera Embedded in a Wristwatch

Michael Ansorge, Pierre-André Farine, Patrick Stadelmann, Steve Tanner

2007