Koninklijke Philips Corporation N.v.

Philips Lighting Holding B.v.

Signify Holding B.v.

Gracenote, Inc.

Nxp B.v.

Constant Paul Marie Jozef Baggen

Paul Henricus Johannes Maria Van Voorthuisen

Aalbert Stek

Ludovicus Marinus Gerardus Maria Tolhuizen

Ronald Rietman

Cornelis Marinus Schep

Andries Pieter Hekstra

Hongming Yang

Sebastian Egner

Job Cornelis Oostveen

Antonius Adrianus Cornelis Maria Kalker

Willem Marie Julia Marcel Coene

Jaap Andre Haitsma

Stephanus Joseph Johannes Nijssen

Marten Erik Van Dijk

Ningjiang Chen

Peter Hoekstra

Benjamin Johannes Vos

Erik Witberg

Mark Thomas Johnson

Shoei Kobayashi

Tamotsu Yamagami

Nicolaas Lambert

Lorenzo Feri

Wilhelmus Petrus Adrianus Johannus Michiels

Frederik Jan De Bruijn

Johan Paul Marie Gerard Linnartz

Ruben Rajagopalan

Arie Geert Cornelis Koppelaar

Tommaso Gritti

Johannus Leopoldus Bakx

Paulus Mathias Hubertus Mechtildis Antonius Gorissen

Nobuyoshi Kobayashi

Victor Martinus Gerardus Van Acht

Martinus Wilhelmus Blum

Hendricus Theodorus Gerardus Maria Penning De Vries

Sri Andari Husen

Andre Melon Barroso

Thomas Falck

Mina Deng

Bastiaan Feddes

Gerardus Rudolph Langereis

Wicher Ido-Jan Gispen

Koen Vanhoof

Wicher I Gispen

Paul Henricus Johannes Maria Van Voorthuisenh

Shinichiro Ilmura

Abraham Jan De Bart

Matthew John Lawrenson

Bas Van Tiel

Julian Charles Nolan

Hendricus Theodorus Gerardus Penning De Vries

An apparatus, method and program for receiving a coded light signal comprising a periodically repeating message repeating with a message period. A portion of the message is received in each of a plurality of frames captured by a rolling-shutter camera, with different portions being received in different frames. Using each of a discrete group of trial values of the message period, the respective trial value is used to reconstruct a respective first version of the message from the portions received in a first subset of said frames, and to reconstruct a respective second version of the message from the portions received in a second subset of said frames. For each of the trial values, there is generate a respective value of a measure of similarity between the respective reconstructed first and second versions of the message. An estimate of the message period is determined based on this.

Clock recovery for a coded light receiver

A coded visible light receiver comprises: a sensor, a transform module, and an interference cancelling module. The sensor receives light comprising data modulated into the light according to a coding scheme. The transform module is configured to transform the data into a frequency domain representation, representing a band of a spectrum resulting from the data being modulated into the light according to the coding scheme. The interference cancelling module is configured to cancel interference occurring in the band of the data, by determining one or more components in the band that exceed a threshold signal strength and cancelling those components.

Receiving coded visible light in presence of interference

A device comprising: an input for receiving a signal from a rolling-shutter camera which captures frames by exposing a lines of each frame in sequence, the signal comprising a coded light signal; and a signal processing module arranged to obtain a respective sample of the coded light signal from each of a number of said lines, being a substantially smaller number of the lines than exposed by the camera in each frame. The coded light signal comprises a message having a duration longer than this number of lines, and the message is repeated multiple times with a timing such that a different part of the message is seen by the camera in each of a plurality of different ones of said frames. The signal processing module is configured to time align the different parts of the message from the plurality of different frames, and reassemble the message from the time-aligned parts.

Coded light

A Wiener filter for equalizing an effect of a first filter on an input signal which is subject to the first filter and to noise and/or interference, wherein: the first filter is dependent on at least one unknown quantity; and the Wiener filter is configured based on an averaged representation of the first filter averaged over the at least one unknown quantity, in place of a representation of the first filter being assumed to be known.

A coded light signal is embedded into visible light emitted from the light source, to be received by a rolling-shutter camera which captures frames () by exposing a plurality of lines () of each frame in sequence, the camera having an exposure time with each line being exposed for the exposure time. The coded light signal is formatted according to a format whereby the coded light signal comprises at least one message and the message is repeated multiple times with a timing such that, when samples of the coded light signal are obtained from a substantially smaller number of lines () than exposed by the camera in each frame and the message is longer than this number of lines, a different part of the message is seen by the camera in each of a plurality of different ones said frames.

The invention relates to an apparatus, a system and a method of locating a location of a portable device using coded light, the portable device comprising an image sensor and an inertial measurement unit, the method comprising: obtaining a first image comprising the coded light source from the image sensor and substantially simultaneously obtaining orientation information indicative of the orientation of the portable device or the image sensor from the inertial measurement unit; obtaining light source specific information in the form of: an identifier that allows retrieval of a three-dimensional location of the coded light source or a three-dimensional location of the coded light source; and computing the location of the portable device or image sensor based on the orientation information, a predetermined height estimate of the portable device or image sensor and the light source specific information.

Locating a portable device based on coded light

A circuit comprising a controller () for controlling a pulse width modulated input signal, and a driver () configured to supply current to a load () based on the input signal, wherein over the on time of each pulse width modulation period the driver () supplies current to the load () with a second frequency that is greater than the first frequency. The controller () is configured to control the duty cycle to set the output of the load () to a desired output level, and to dither the duty cycle about a point corresponding to the desired output level.

Circuit and method for controlling pulse width modulation of a current supply for a load

A compilerfor compiling a first computer programwritten in a first computer programming language into a second computer program written in a machine language, the compiler comprises a code generator to generate the second computer program by generating tablesand machine language code, the generated tables and the generated machine language code together forming the second computer program, wherein the generated machine language code references the tables and the generated machine language code does not contain arithmetic or logic machine instructions, the tables comprising pre-computed results of arithmetic and/or logic machine instructions.

Compiler generating operator free code

A coded light receiver comprising a sensor for receiving coded light, a filter, and a timing and data recovery module. The coded light comprises a signal whereby data and timing are modulated into the light according to a self-clocking coding scheme. The filter is arranged to match a template waveform of the coding scheme against the received signal, thereby generating a pattern of filtered waveforms each corresponding to a respective portion of the data, and the timing and data recovery module recovers the timing from the signal based on characteristic points of the filtered waveforms. The timing and data recovery module is configured to do this by separating the filtered waveforms into different sub-patterns in dependence on the data, and to recover the timing by processing each of the sub-patterns individually based on the characteristic points of each sub-pattern.

Recovering timing from a self-clocking coded light signal

A fall detector includes an accelerometer for producing a time series of measurement samples representing the acceleration acting on the fall detector; a processor for estimating a vertical velocity and/or displacement of the fall detector from the measurement samples and using the estimated vertical velocity and/or displacement to determine whether the user has suffered a fall. The processor is configured to estimate a vertical velocity and/or displacement of the fall detector by estimating a corresponding time series of unit vectors representing acceleration due to gravity in the reference frame of the accelerometer from the time series of measurement samples; projecting each measurement sample onto the corresponding unit vector and subtracting acceleration due to gravity to give a series of estimates for the vertical acceleration of the fall detector; and integrating the series of estimates to give a time series of values for the vertical velocity and/or displacement of the fall detector.

Method for estimating velocities and/or displacements from accelerometer measurement samples

A record carrier has a servo track indicating an information track intended for recording information blocks. The servo track has a variation of a physical parameter, referred to as wobble. The wobble is modulated for encoding record carrier information, such as addresses. The servo track is subdivided in modulated parts in which the frequency and/or phase of the variation deviates from the wobble frequency, and non-modulated parts. The slope of the wobble is substantially continuous at transitions between the modulated and non-modulated parts by using wobbles starting at the maxima or minima of the wobble in a first part of the modulated parts.

Record carrier and apparatus for scanning the record carrier

According to one aspect of the disclosure, a lighting system comprises a remote control unit () and at least one lighting device () comprising a light driver () and a light emitter (). The remote control unit () comprises an image capturing unit () and is arranged to control the lighting device (). To do so, the remote control unit () receives information relating to current/present settings of the image capturing unit (), then determines one or more properties of signals for visible light communications based on these settings. The one or more properties are then communicated to the at least one lighting device (). Upon reception thereof the light driver () generates a light emitting control signal based on the received properties and visible light communications based on the light emitting control signal is emitted by the light emitter (). According to another aspect, a lighting device () adapts emitted modulated light and adapts the modulation so as not to correspond to blind-spots of an image capture unit ().

Visible light communications using a remote control

Coded light has been proposed to enable advanced control of light sources and transmit information using light sources. Sequences of channel symbols to drive the light source are determined from sequences of source symbols such that no visible flicker is present in coded light emitted by the light sources. Each source symbol is mapped to a composite channel symbol comprising at least one first channel symbol which may be identical to the current source symbol and at least one second channel symbol which may be a function of the current source symbol and at least one future and/or past source symbol.

Modulation for coded light transmission

A method for detecting a fall by a user includes a method of detecting a fall by a user. The method includes processing measurements obtained from one or more sensors to extract a respective value for a plurality of features associated with a fall. A respective log likelihood ratio for each of the values is determined. Whether the user has fallen is determined based on the determined log likelihood ratios.

Method for detecting falls and a fall detector

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Eindhoven, Netherlands

Constant Paul Marie Jozef Baggen