Abstract: A comparator circuit (5) comprising a fully differential main amplifier unit (10, 10b). The main amplifier unit (10, 10b) comprises a control port and is adapted to control a bias current of a first branch of the main amplifier unit (10, 10b) and/or a bias current of a second branch of the main amplifier unit (10, 10b) in response to one or more control voltages supplied to the control port of the main amplifier unit (10, 10b). The comparator circuit (5) comprises circuitry (60) for balancing the voltages at the positive and negative input terminals (12a, 12b) of the main amplifier unit (10, 10b) during a first clock phase of the comparator circuit (5). Furthermore, the comparator circuit (10, 10a) comprises a switched-capacitor accumulator unit with a differential input.

Abstract: Systems and methods which implement a transconductor replica feedback (TRF) block in a transconductor circuit are shown. In accordance with embodiments, the TRF block comprises a feedback transistor disposed as a replica of a corresponding transconductance transistor of the transconductor circuit. The TRF block provides enhanced looking-in degeneration impedance for the transconductor circuit, thereby allowing for higher linearity and lower power at the same time. TRF transconductors of embodiments can be implemented in, or otherwise applied to, various different circuits such as LNAs, filters, etc.

Abstract: The present invention relates generally to methods and apparatuses for estimating and correcting for multipath in GNSS navigation systems. According to some aspects, the invention takes advantage of situations where position and estimated position error are reasonably stable so as to detect when large multipath errors are present with confidence. After detection, the slowly varying biases from multipath or other un-modeled sources can be modeled separately from the navigation state. This makes it possible to keep the measurements in the solution without biasing the navigation state and further ignores the long-term biases for use over short-term periods with minimized pseudorange error when necessary.

Abstract: A method for generating phase signals includes triggering a phase register to output a binary number stored in the phase register, wherein the phase register is triggered based at least in part on a voltage signal provided by a voltage controlled oscillator. The method also includes providing an input signal to a decoder, wherein the input signal is based at least in part on the binary number output by the phase register and the decoder is operable to generate phase signals in response to the input signals. The method further includes incrementing the binary number stored in the phase register and repeating the triggering and providing steps after the binary number is incremented.

Abstract: Systems and methods directed to determining motion in a video signal are provided. A plurality of pixels of a plurality of adjacent field lines of alternating parity of the video signal are evaluated to generate a plurality of differential values. A sign of each differential value is determined, and when each differential value has the same sign, at least one differential value can be compared with a threshold value. Responsive to the comparison of at least one differential value with a threshold value, a motion coefficient indicative of a magnitude of motion associated with one of the plurality of pixels can be generated.

Abstract: Methods for estimating illumination parameters under flickering lighting conditions are disclosed. Illumination parameters, such as phase and contrast, of a intensity-varying light source may be estimated by capturing a sequence of video images, either prior to or after a desired still image to be processed. The relative average light intensities of the adjacently-captured images are calculated and used to estimate the illumination parameters applicable to the desired still image. The estimated illumination parameters may be used to calculate the point spread function of a still image for image de-blurring processing. The estimated illumination parameters may also be used to synchronize the exposure timing of a still image to the time when there is the most light, as well as for use in motion estimation during view/video modes.

Abstract: A signal processing system for processing satellite positioning signals is described. The system comprises at least one processor and a signal processor operating under a number of operational modes. The signal processor includes at least one of a signal processing subsystem, a fast Fourier transform (FFT) subsystem, and a memory subsystem that are each dynamically and independently configurable in response to the operational modes. Further, the system includes a controller that couples to control transfer of data among the signal processing subsystem and the FFT subsystem via the memory subsystem. Configurability of the memory subsystem includes configuring the memory subsystem into regions according to the operational modes where each region is accessible in one of a number of manners according to the operational modes.

Abstract: Systems and methods which provide a multimode tuner architecture implementing direct frequency conversion are shown. Embodiments provide a highly integrated configuration wherein low noise amplifier, tuner, analog and digital channel filter, and analog demodulator functionality are provided in a single integrated circuit. A LNA of embodiments implements a multi-path configuration with seamless switching to provide desired gain control while meeting noise and linearity design parameters. Embodiments of the invention implement in-phase and quadrature (IQ) equalization and a multimode channelization filter architecture to facilitate the use of direct frequency conversion. Embodiments implement spur avoidance techniques for improving tuner system operation and output using a clock signal generation architecture in which a system clock, sampling clock frequencies, local oscillator (LO) reference clock frequencies, and/or the like are dynamically movable.

Abstract: Circuitry for controlling mode selection of a CD/DVD reader is described. In one embodiment, the CD/DVD reader has a first device having at least one analog output, a second device having at least one digital input and at least one analog input, and an interface circuit coupling the analog output of the first device to the digital input and the analog input in the second device. The interface circuit includes a circuitry to use a single control signal from the analog output of the first device to control the digital input and the analog input in the second device. Other embodiments are also described.

Abstract: Embodiments of integrated circuits for use in a broadband tuner are described. In one embodiment, an integrated circuit includes a clock buffer configured to buffer a received clock signal and generate a buffered clock signal. Additionally, the integrated circuit includes a multiphase local oscillator core coupled to the clock buffer and configured to generate a plurality of oscillator signals in response to the buffered clock signal, each of the plurality of oscillator signals being mutually phase shifted. The integrated circuit may also include a plurality of output buffers, each configured to receive one of the plurality of oscillator signals and to produce an output signal suitable for use in a broadband tuner circuit in response to the one of the plurality of oscillator signals.

Abstract: A device and methods are provided for producing a high dynamic range (HDR) image of a scene are disclosed and claimed. In one embodiment, method includes setting an exposure period of an image sensor of the digital camera and capturing image data based on the exposure period. The method may further include checking the image data to determine whether the number of saturated pixels exceeds a saturation threshold and checking the image data to determine whether the number of cutoff pixels exceeds a cutoff threshold. The method may further include generating a high dynamic range image based on image data captured by the digital camera, wherein the high dynamic range image is generated based on a minimum number of images to capture a full dynamic range of the scene.

Abstract: A system, method, and computer program product for automatically detecting and correcting the “purple fringing” effect, typically due to axial chromatic aberration in imaging devices, are disclosed and claimed. A chromaticity score is computed, denoting the amount of false color related to a purple fringing artifact. A locality score is computed, denoting the similarity of the purple fringing region to a shape of a narrow ridge, which is typical for purple fringing artifacts. A saturation score is also computed, denoting the proximity of a pixel to saturated pixels. These scores are then combined into a detection score, denoting pixels having strong indications they share properties common to pixels of purple fringing artifacts. The detected pixels are then correspondingly corrected, e.g. by chroma suppression. The scoring and correction may be performed over combinations of image resolutions, e.g. an original version and potentially numerous downscaled versions.

Abstract: A PLL circuit (1a, 1b) for generating a pixel-clock signal based on a hsync signal. The PLL circuit comprises a phase-frequency detector arranged to receive the hsync signal and a frequency divided pixel-clock signal, and generate up and down signals based on the hsync signal and the frequency-divided pixel-clock signal. A charge pump (20) is arranged to generate an output signal based on the up and down signals and a loop filter (30) is arranged to generate a frequency-control signal based on the output signal of the charge pump (20). Furthermore, a VCO (40a, 40b) is arranged to generate an oscillating signal and adjust the frequency of the oscillating signal in response to the frequency-control signal. The VCO (40a, 40b) is adapted to have a tuning range with a center frequency which is larger than or equal to 4 GHz.

Abstract: Systems and methods for sharing an oscillator between receivers are disclosed. A representative method (among others) of responding to a change in frequency of a voltage-controlled temperature-compensated oscillator (VCTCXO), includes: determining a new value for VCTCXO frequency; determining a time at which the new value will be applied to the VCTCXO; transmitting the time and the new value to a subsystem that uses a second receiver which shares the VCTCXO with a first receiver; and in the subsystem, updating channel context data to use the time of the change in frequency and the new value.

Abstract: Techniques for creating a High Dynamic Range (HDR) image within a consumer grade digital camera from a series of images of a scene captured at different exposure levels, and displaying the HDR image on the camera's built-in display are provided. The approach employs mixing images of the series to incorporate both scene shadow and highlight details, and the removing of “ghost” image artifacts appearing in the mixed HDR image resulting from movement in the scene over the time the series images are captured. The low computational resource utilization of the image mixing and ghost removal processing operations, along with the ability to commence image mixing and ghost removal prior to the acquisition of all series images, can significantly reduce the time required to generate and display a tone mapped HDR image.

Abstract: Techniques for reducing coloration artifacts visible in digital images acquired under flash lighting conditions are provided. The coloration artifact problem is addressed by capturing two images of the scene, a first image illuminated by a limited spectral bandwidth flash light source, and a second image illuminated by broad spectral bandwidth flash light source. Pixels of the second image are replaced with selected counterpart pixels from the first image that do not contain the coloration artifact.

Abstract: Embodiments are directed towards determining within a digital camera whether a pixel belongs to a foreground or background segment within a given image by evaluating a ratio of derivative and deviation metrics in an area around each pixel in the image, or ratios of derivative metrics across a plurality of images. For each pixel within the image, a block of pixels are examined to determine an aggregate relative derivative (ARD) in the block. The ARD is compared to a threshold value to determine whether the pixel is to be assigned in the foreground segment or the background segment. In one embodiment, a single image is used to determine the ARD and the pixel segmentation for that image. Multiple images may also be used to obtain ratios of a numerator of the ARD, useable to determine an extent of the foreground.

Abstract: A camera that provides for a panorama mode of operation that employs internal software and internal acceleration hardware to stitch together two or more captured images to create a single panorama image with a wide format. Captured images are projected from rectilinear coordinates into cylindrical coordinates with the aid of image interpolation acceleration hardware. Matches are quickly determined between each pair of images with a block based search that employs motion estimation acceleration hardware. Transformation are found, utilizing regression and robust statistics techniques, to align the captured images with each other, which are applied to the images using the interpolation acceleration hardware. A determination is made for an optimal seam to stitch images together in the overlap region by finding a path which cuts through relatively non-noticeable regions so that the images can be stitched together into a single image with a wide panoramic effect.

Abstract: A system, method, and computer program product for automatically detecting and correcting the “purple fringing” effect, typically due to axial chromatic aberration in imaging devices, are disclosed and claimed. A chromaticity score is computed, denoting the amount of false color related to a purple fringing artifact. A locality score is computed, denoting the similarity of the purple fringing region to a shape of a narrow ridge, which is typical for purple fringing artifacts. A saturation score is also computed, denoting the proximity of a pixel to saturated pixels. These scores are then combined into a detection score, denoting pixels having strong indications they share properties common to pixels of purple fringing artifacts. The detected pixels are then correspondingly corrected, e.g. by chroma suppression. The scoring and correction may be performed over combinations of image resolutions, e.g. an original version and potentially numerous downscaled versions.

Abstract: According to certain aspects, the invention provides a method of achieving near-fingerprinting accuracy without fingerprinting database costs, via parametric representation of training data. In embodiments, this is achieved by using a parametric representation for the training data and limiting the region of applicability of the parametric model in order to mimic fingerprinting. According to certain additional aspects, an algorithm according to principles of the invention includes two separate parts, training and positioning. Training encompasses the derivation of the parametric model and region of applicability. This comprises access point position, propagation model and the window of applicability. Positioning covers the use of the derived model along with a set of fresh observations to generate a position estimate.