Abstract:
An image sensor may have an array of image sensor pixels arranged in color filter unit cells each having one red image pixel that generates red image signals, one blue image pixel that generate blue image signals, and two clear image sensor pixels that generate white image signals. The image sensor may be coupled to processing circuitry that performs filtering operations on the red, blue, and white image signals to increase noise correlations in the image signals that reduce noise amplification when applying a color correction matrix to the image signals. The processing circuitry may extract a green image signal from the white image signal. The processing circuitry may compute a scaling value that includes a linear combination of the red, blue, white and green image signals. The scaling value may be applied to the red, blue, and green image signals to produce corrected image signals having improved image quality.
Abstract:
Imaging systems may be provided with stacked-chip image sensors. A stacked-chip image sensor may include a vertical chip stack that includes an array of image pixels, control circuitry and storage and processing circuitry. The image pixel array may be coupled to the control circuitry using vertical metal interconnects. The control circuitry may provide digital image data to the storage and processing circuitry over additional vertical conductive. The stacked-chip image sensor may be configured to capture image frames at a capture frame rate and to output processed image frames at an output frame rate that is lower that the capture frame rate. The storage and processing circuitry may be configured to process image frames concurrently with image capture operations. Processing image frames concurrently with image capture operations may include adjusting the positions of moving objects and by adjusting the pixel brightness values of regions of image frames that have changing brightness.
Abstract:
An image sensor may include an image pixel array with both image pixels to gather image data and phase detection pixels to gather phase information. The phase detection pixels may be arranged in pairs, with two adjacent pixels covered by a single microlens. The phase detection pixel pairs may be arranged in dashed lines, with image pixels interposed between each phase detection pixel pair. There may be only one image pixel interposed between each phase detection pixel pair. The phase detection pixels may all include color filter elements of the same color. The phase detection pixels may all include green color filter elements. The image pixels in the interrupted lines may include color filter elements that match the surrounding color pattern. The image pixels in the interrupted lines may all include color filter elements of the same color.
Abstract:
Imaging devices may include processing circuitry, a lens, and an array of image sensor pixels and reference pixels. The array may receive direct image light and stray light from the lens. The image sensor pixels may include clear color filter elements and the reference pixels may include opaque color filter elements. The opaque color filter elements may block direct image light from being captured by the reference pixels. The image sensor pixels may generate pixel values in response to the direct image light and the stray light whereas the reference pixels may generate reference pixel values in response to the stray light. The processing circuitry may mitigate stray light effects such as local flare and veiling glare within the imaging system by adjusting the pixel values based on the reference pixel values. The imaging system may be calibrated in a calibration system for generating stray light calibration data.
Abstract:
An image sensor may have an array of image sensor pixels arranged in color filter unit cells each having one red image pixel that generates red image signals, one blue image pixel that generate blue image signals, and two clear image sensor pixels that generate white image signals. The image sensor may be coupled to processing circuitry that performs filtering operations on the red, blue, and white image signals to increase noise correlations in the image signals that reduce noise amplification when applying a color correction matrix to the image signals. The processing circuitry may extract a green image signal from the white image signal. The processing circuitry may compute a scaling value that includes a linear combination of the red, blue, white and green image signals. The scaling value may be applied to the red, blue, and green image signals to produce corrected image signals having improved image quality.
Abstract:
An imaging system may include an image sensor having pixels with stacked photodiodes in which a first photodiode generates a first image signal in response to light of a first wavelength and a second photodiode generates a second image signal in response to light of a second wavelength. The imaging system may include processing circuitry that applies a color correction matrix to isolate components of the first and second signals that are generated in response to light of the first and second wavelengths while removing components of the first and second signals that are generated in response to light of other wavelengths. The processing circuitry may increase noise correlations between the signals to mitigate noise amplification generated by the color correction matrix. The processing circuitry may apply a point filter to increase luma fidelity of the signals.
Abstract:
An imaging system may include an image sensor having pixels with stacked photodiodes in which a first photodiode generates a first image signal in response to light of a first wavelength and a second photodiode generates a second image signal in response to light of a second wavelength. The imaging system may include processing circuitry that applies a color correction matrix to isolate components of the first and second signals that are generated in response to light of the first and second wavelengths while removing components of the first and second signals that are generated in response to light of other wavelengths. The processing circuitry may increase noise correlations between the signals to mitigate noise amplification generated by the color correction matrix. The processing circuitry may apply a point filter to increase luma fidelity of the signals.
Abstract:
An imaging system may capture image data and use the captured image data to detect a privacy request. Depending on the specific privacy request, the imaging system may delete or blur the captured image to comply with the detected privacy request. The imaging system may use face recognition software and only blur faces that are present in the captured image, leaving the rest of the image unobscured. The imaging system may only comply with the privacy request if the imaging system is in a predetermined area or within a predetermined distance of a privacy seeking external device. The imaging system may be disabled if the system enters a geo-fenced area that restricts the capture of images. The imaging system may recognize a given temporal pattern of light as a privacy request and modify any captured images accordingly.
Abstract:
An image sensor may have an array of image pixels arranged in color filter unit cells that each have at least one red image pixel that generates red image signals, at least one blue image pixel that generate blue image signals, at least one clear image pixels that generate clear image signals, at least one infrared image pixel that generates infrared image signals, and optionally at least one green image pixel that generates green image signals. The image sensor may be coupled to processing circuitry that performs chroma demosaicking operations on the image signals. The processing circuitry may generate an infrared image using the infrared image signals and a luminance value using the clear, red, blue, and infrared image signals. The processing circuitry may perform point filter operations on the image signals based on the generated luminance value to produce corrected visible light image signals having improved image quality.
Abstract:
An image sensor may have an array of image sensor pixels arranged in color filter unit cells each having one red image pixel that generates red image signals, one blue image pixel that generate blue image signals, and two clear image sensor pixels that generate white image signals. The image sensor may be coupled to processing circuitry that performs filtering operations on the red, blue, and white image signals to increase noise correlations in the image signals that reduce noise amplification when applying a color correction matrix to the image signals. The processing circuitry may extract a green image signal from the white image signal. The processing circuitry may compute a scaling value that includes a linear combination of the red, blue, white and green image signals. The scaling value may be applied to the red, blue, and green image signals to produce corrected image signals having improved image quality.