Abstract: Each of a first and second image acquisition device includes: a circuit for providing a primary clock signal and a frequency synthesizing circuit capable of generating at least one secondary clock signal from said primary clock signal. The frequency synthesizing circuit in each image acquisition device has a fractional phase-locked loop configuration. A synchronization comparison circuit in each image acquisition device functions to compare sync between an external sync signal and an internal sync signal. An adjustment of the fraction phase lock loop operation is made in response to the sync comparison.

Abstract: Ambient light is detected by a photodiode circuit by measuring the time taken for a digital output of the photodiode circuit to change state in response to exposure of a photodiode of the photodiode circuit to that ambient light. A nominal time for state change is calculated based on photodiode circuit characteristics. Furthermore, an effective time for the photodiode circuit digital output to change state is determined in a calibration mode where the photodiode has been disconnected and a reference current is applied to the circuit. An illumination value of the detected ambient light is then calculated as a function of: the measured time, the effective time and the nominal time.

Abstract: A method and apparatus for defining, from a first periodic signal, a second signal of same period, including the steps of: generating a third signal exhibiting detectable events; and synchronizing the second signal for each event.

Abstract: A method of generation, by a digital processing device, of a first high dynamic range digital image from second and third digital images of a same scene, including, for at least one point of the first image: determining a brightness index; comparing this index with at least one of first, second, third, and fourth decreasing thresholds stored in a memory; and determining the value of the point by taking into account the value of the index.

Abstract: A method is for monitoring the electrical integrity of lines of photosites of an imaging device with matrix array of photosites. The control lines of photosites may include for each line of photosites an emission of elementary electrical control signals for the photosites of the line. The method may include diagnosis of the elementary electrical control signals emitted.

Abstract: A device includes an image sensor and a circuit for controlling the sensor. The control circuit is configured control the device in a first operating mode and second operating mode. In the first operating mode images acquired by the sensor are output. In the second operating mode, no images are provided, but a selected subassembly of pixels of the image sensor are read and image data therefrom is processed to provide an ambient luminosity value.

Abstract: A method wherein the updating of a counter is triggered when a photodiode reaches a discharge threshold.

Abstract: An optical navigation device is provided for detecting movement of a pointer, such as a finger, in three dimensions. A sensor obtains images of the pointer which have been illuminated by an illumination source, and an image scaling module determines the difference in size between images acquired by the image sensor to determine the difference in height of the pointer between images.

Abstract: A motion capture device for communicating with a host device in order to input captured motion. The device includes an amplifier module structured to weight displacement measurements by a gain, and an adjustment module structured to adjust the gain as a function of a speed of the capture device.

Abstract: An optical mouse includes an image sensor for providing image data via an analog-to-digital converter to a correlation circuit and a motion estimation circuit to provide output signals representative of motion of the mouse. The output signals may be disabled when the mouse is lifted away from the working surface. This may be achieved by high-pass filtering the signals, summing each frame in a summer to provide a single value, and comparing this to a threshold. If the filtered and summed value exceeds the threshold, this may indicate that the image contains in-focus objects, and that the mouse is on the working surface.

Abstract: A method and apparatus for defining, from a first periodic signal, a second signal of same period, including the steps of: generating a third signal exhibiting detectable events; and synchronizing the second signal for each event.

Abstract: A method is for monitoring the electrical integrity of lines of photosites of an imaging device with matrix array of photosites. The control lines of photosites may include for each line of photosites an emission of elementary electrical control signals for the photosites of the line. The method may include diagnosis of the elementary electrical control signals emitted.

Abstract: A device for transferring charges photogenerated in a portion of a semiconductor layer delimited by at least two parallel trenches, each trench including, lengthwise, at least a first and a second conductive regions insulated from each other and from the semiconductor layer, including the repeating of a first step of biasing of the first conductive regions to a first voltage to form a volume accumulation of holes in the area of this portion located between the first regions, while the second conductive regions are biased to a second voltage greater than the first voltage, and of a second step of biasing of the first regions to the second voltage and of the second regions to the first voltage.

Abstract: In relation to a current image from a sequence of images captured by an image sensor, in a first step, a temporary motion vector is determined as a function of reference data comprising a preceding image and a motion vector associated to the preceding image. Then, in a second step, if the temporary motion vector does not satisfy a reliability criterion, the first step is repeated in relation to a following image, on the basis of the same reference data. Otherwise, the temporary motion vector is associated with the current image.

Abstract: A process for determining the displacement of an entity equipped with a sensor for capturing a sequence of images, comprising a step for determining a motion vector associated with a current image as a function of at least one correlation calculation between a first block of pixels in the current image and a second block of pixels from which the vector points towards said first block of pixels, with said second block being in a previous image in the sequence of images, wherein the dimensions of the first block are determined as a function of at least a motion vector associated with a previous image in the image sequence.

Abstract: A method is provided for reading a captured image, with the captured image comprising at least first and second parts and a border area positioned between the first and second parts. Converted pixels are obtained by applying digital-to-analog conversion to the pixels in the captured image, and the converted pixels corresponding to the border area of the captured image are stored in a buffer. A first set of processed pixels is obtained by applying image processing to the converted pixels corresponding to the first part of the image and to the converted pixels stored in the buffer, and a second set of processed pixels is obtained by applying image processing to the converted pixels corresponding to the second part of the image and to the converted pixels stored in the buffer. A processed image is provided by combining the first and second sets of processed pixels. Also provided is a processing device for reading a captured image.

Abstract: A motion estimation method is provided for processing successive images in an image sequence, with a motion vector being associated with each of the processed images. For a current image, motion vectors associated with images that precede the current image in the sequence are selected. Candidate motion vectors are generated from the motion vectors that are selected. A motion vector is elected from among the candidate motion vectors. Information that associates the elected motion vector with the current image is stored in memory. At least one of candidate motion vectors is an acceleration vector generated from the acceleration between first and second motion vectors averaged relative to a first and second images, with the first and second images being distinct and preceding the current image in the image sequence. A motion vector averaged relative to a given image is obtained from selected motion vectors associated with images preceding the given image.

Abstract: An image sequence sensor senses images. To associate a motion vector with an image of the sequence currently being processed, k candidate vectors are generated by adding, to a reference motion vector, respectively k search vectors. Then, a motion vector is selected from among the k candidate vectors as a function of a selection rule. Thereafter, the previous two steps are repeated m times, the reference motion vector being on the one hand, for a first iteration of the first step, an initial reference vector selected from among a set of vectors comprising at least one motion vector associated with a previous processed image and being on the other hand, for the m repetitions of the first step, the motion vector selected in the second step preceding the first step. Then, the vector obtained in the third step is associated with the image currently being processed.

Abstract: Ambient light is detected by a photodiode circuit by measuring the time taken for a digital output of the photodiode circuit to change state in response to exposure of a photodiode of the photodiode circuit to that ambient light. A nominal time for state change is calculated based on photodiode circuit characteristics. Furthermore, an effective time for the photodiode circuit digital output to change state is determined in a calibration mode where the photodiode has been disconnected and a reference current is applied to the circuit. An illumination value of the detected ambient light is then calculated as a function of: the measured time, the effective time and the nominal time.

Abstract: A method is provided for reading a captured image, with the captured image comprising at least first and second parts and a border area positioned between the first and second parts. Converted pixels are obtained by applying digital-to-analog conversion to the pixels in the captured image, and the converted pixels corresponding to the border area of the captured image are stored in a buffer. A first set of processed pixels is obtained by applying image processing to the converted pixels corresponding to the first part of the image and to the converted pixels stored in the buffer, and a second set of processed pixels is obtained by applying image processing to the converted pixels corresponding to the second part of the image and to the converted pixels stored in the buffer. A processed image is provided by combining the first and second sets of processed pixels. Also provided is a processing device for reading a captured image.