Koninklijke Philips Corporation N.v.

Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno

Stichting Vu

Mathivanan Damodaran

Jonathan Alambra Palero

Yannyk Parulian Julian Bourquin

Rieko Verhagen

Michel Jozef Agnes Asselman

Babu Varghese

Willem Auke Westerhof

Oedilius Johannes Bisschop

Lu Wang

Stephanus Jacob Gerardus Tamminga

Arjen Amelink

Emilie Cuillery

Johannes Fitzgerald De Boer

Stephanus Jacob Gerardus Temminga

Verhagen Rieko

According to an aspect, there is provided a method for minimising error in ambient light corrected image due to motion, the method comprising: capturing a plurality of primary images with controlled intensity of illumination varying over time, estimating an error value due to motion for each of a plurality of sub-sets of the plurality of primary images, and performing ambient light correction on an error minimised sub-set of primary images having the lowest estimated error value to generate an ambient light corrected (ALC) image with a minimised error. Estimating the error value for each sub-set of the plurality of primary images comprises identifying a pair of primary images in the sub-set including a first primary image and a second primary image, wherein the first primary image is captured temporally before the second primary image, determining a displacement vector matrix between the pair of primary images, and estimating the error value for the sub-set of primary images based on the displacement vector matrix between the pair of primary images. Determining the displacement vector matrix includes dividing the first primary image into a plurality of first grid elements and dividing the second primary image into a plurality of second grid elements, matching first grid elements to second grid elements which correspond to the same position on the object, and determining a displacement vector between each matched first grid element and second grid element to determine a displacement vector matrix describing the displacement vector of each grid element.

Method and image capturing apparatus for minimising error in ambient light corrected images

According to an aspect, there is provided a method for minimising error in ambient light corrected (ALC) images due to motion. The method comprises capturing a plurality of primary images of an object over a time window, with controlled illumination of the object varying over time, performing ambient light correction on at least a portion of the plurality of primary images to generate a plurality of ambient light corrected images, each ALC image being generated based on demodulating a sub-set of the plurality of primary images with differing controlled illumination, calculating an error value for pairs of ALC images, each pair of ALC images including a first ALC image and a second ALC image and comparing the error values for each pair of ALC images and selecting an error-minimised image from the pair of ALC images having the lowest error value within the time window Calculating the error value comprises comparing each pixel of the first ALC image with a corresponding pixel of the second ALC image, and determining a change in intensity for each pixel between the first ALC image and the second ALC image, and calculating an error value for the pair of ALC images based on the change in intensity over a plurality of pixels.

Method and image capturing apparatus

According to an aspect, there is provided a system () comprising a hair cutting device () having a cutting element for cutting a subject's hair; a localisation unit () for acquiring location data indicative of a location of the cutting element relative to a body part of the subject; a timer unit () for measuring time data associated with usage of the hair cutting device; and a processing unit () in communication with the hair cutting device, the localisation unit and the timer unit, the processing unit being configured to determine, based on the location data and the time data, an operating parameter to be applied to the hair cutting device.

Determining operating parameters of hair cutting devices

In an embodiment, a method () is described. The method is a computer-implemented method. The method comprises receiving () pixel information corresponding to at least part of a first, second and third image, acquired by an imaging system, of a subject illuminated by temporally modulated illumination. A time delay between an acquisition start time of the first, second and third images is such that there is an overlap in time during acquisition of the first, second and third images. The method further comprises determining () modified pixel information for constructing a modified image of the subject. The modified pixel information is determined based on: a difference between the received pixel information of the first, second and third images to reduce an effect of ambient lighting in the received pixel information; and a combination of the received pixel information to cancel out a spatial intensity modulation pattern apparent in each of the first, second and third images. The spatial intensity modulation pattern is due to a timing relationship between an imaging time period over which the imaging system acquires each image and a modulation time period of the temporally modulated illumination.

Determining pixel information

According to an aspect, there is provided a system () comprising: an image projection unit () configured to project an illumination pattern onto at least a portion of a scene, an imaging unit () configured to capture a plurality of images of the scene while the illumination pattern is projected onto the scene, and a processing unit () configured to: demodulate the plurality of images based on the illumination pattern and with respect to a target section in the plurality of captured images, wherein the target section corresponds to one of: a portion of the scene on which the illumination pattern is selectively projected while the plurality of images were captured, a portion of the scene at which the projected illumination pattern is resolvable, a portion of the scene with pixel depth values which satisfy a predetermined range; and generate an ambient light suppressed image of the scene based on results of the demodulation.

Ambient light suppression

In an embodiment, a method () is described. The method includes accessing () data from a sequence of images of a subject illuminated with ambient light and illumination having a sinusoidal intensity modulation in time. An imaging device is used to obtain the sequence of images and is configured such that a different spatial intensity modulation pattern is apparent in consecutive images of the sequence. The method further includes determining (), based on a set of measured pixel intensity values in each of the sequence of images, a set of revised pixel intensity values for generating a revised image of the subject such that a reduced level of ambient lighting is apparent in the revised image compared with the level of ambient lighting apparent in at least one of the sequence of images.

Determining pixel intensity values in imaging

Growing community of inventors

'S-Hertogenbosch, Netherlands

Mathivanan Damodaran