A system for selectively modifying gating rate in a single photon avalanche diode (SPAD) is configurable to access first frame metadata associated with a first image frame. The first image frame is captured by performing a first plurality of gate operations to configure the SPAD array to enable photon detection over a frame capture time period. The first plurality of gate operations is performed at a first gating rate such that the first plurality of gate operations comprises a first quantity of gate operations performed over the frame capture time period. The system is further configurable to define a second gating rate based on the first frame metadata and capture a second image frame by performing a second plurality of gate operations to configure the SPAD array to enable photon detection at the second gating rate.

When imaging bright objects, a conventional detector array can saturate, making it difficult to produce an image with a dynamic range that equals the scene's dynamic range. Conversely, a digital focal plane array (DFPA) with one or more m-bit counters can produce an image whose dynamic range is greater than the native dynamic range. In one example, the DFPA acquires a first image over a relatively brief integration period at a relatively low gain setting. The DFPA then acquires a second image over longer integration period and/or a higher gain setting. During this second integration period, counters may roll over, possibly several times, to capture a residue modulus 2.sup.m of the number of counts (as opposed to the actual number of counts). A processor in or coupled to the DFPA generates a high-dynamic range image based on the first image and the residues modulus 2.sup.m.

An imaging apparatus includes a pixel and a memory. The pixel includes a photoelectric conversion circuit and a charge/voltage conversion circuit. The memory is arranged so as to correspond to the pixel on a one-on-one basis and includes a plurality of voltage holding circuits each configured to hold a voltage signal output from the pixel. The voltage holding circuits hold respective voltage signals in different accumulation periods in the pixel and the voltage holding circuits are connected in parallel. The voltage signals in the different accumulation periods are averaged into an averaged voltage signal.

Techniques are described for efficient staggered high-dynamic-range (HDR) output of an image captured using a high-pixel-count image sensor based on pixel binning followed by luminance-guided upsampling. For example, an image sensor array is configured according to a red-green-blue-luminance (RGBL) CFA pattern, such that at least 50-percent of the imaging pixels of the array are luminance (L) pixels. In each image capture time window, multiple (e.g., three) luminance-enhanced (LE) component images are generated. Each LE component image is generated by exposing the image sensor to incident illumination for a respective amount of time, using pixel binning during readout to generate appreciably downsampled color and luminance capture frames, generating an upsampled luminance guide frame from the luminance capture frame, and using the upsampled luminance guide frame to guide upsampling (e.g., and remosaicking) of the color capture frame. The resulting LE components images can be digitally combined to generate an HDR output image.

Systems and methods are disclosed for image signal processing. For example, methods may include receiving a current image of a sequence of images from an image sensor; combining the current image with a recirculated image to obtain a noise reduced image, where the recirculated image is based on one or more previous images of the sequence of images from the image sensor; determining a noise map for the noise reduced image, where the noise map is determined based on estimates of noise levels for pixels in the current image, a noise map for the recirculated image, and a set of mixing weights; recirculating the noise map with the noise reduced image to combine the noise reduced image with a next image of the sequence of images from the image sensor; and storing, displaying, or transmitting an output image that is based on the noise reduced image.

An image processing apparatus that generates a combined image by performing gamma processing and combination processing for a plurality of images obtained by capturing images of the same image capturing-target scene under different exposure conditions and includes: an acquisition unit configured to acquire adjustment parameters that adjust gamma characteristics applied to the gamma processing in accordance with a dynamic range of the image capturing-target scene; a gamma processing unit configured to perform the gamma processing to which adjustment parameters acquired by the acquisition unit have been applied for the plurality of images; and a combination unit configured to generate the combined image by performing the combination processing for the plurality of images for which the gamma processing has been performed by the gamma processing unit.

An imaging device includes an imaging unit including a plurality of pixels, respectively including photoelectric converters and charge accumulation nodes that accumulate signal charge. The imaging unit outputs image data based on signals corresponding to the signal charge accumulated in the charge accumulators. The imaging device includes an image processing unit that processes the image data output by the imaging unit. The imaging unit sequentially outputs a plurality of pieces of image data in one frame period by performing readout nondestructively. The image processing unit generates difference image data by determining a difference between two pieces of image data, selects output image data from initial image data and the difference image data, and combines the output image data and normal readout image data included in the plurality of pieces of image data, to generate combination-result image data.

An imaging device includes an imaging unit including a plurality of pixels, respectively including photoelectric converters and charge accumulation nodes that accumulate signal charge. The imaging unit outputs image data based on signals corresponding to the signal charge accumulated in the charge accumulators. The imaging device includes an image processing unit that processes the image data output by the imaging unit. The imaging unit sequentially outputs a plurality of pieces of image data in one frame period by performing readout nondestructively. The image processing unit generates difference image data by determining a difference between two pieces of image data, selects output image data from initial image data and the difference image data, and combines the output image data and normal readout image data included in the plurality of pieces of image data, to generate combination-result image data.

A vertically stacked image sensor with HDR imaging functionality and a method of operating the same are disclosed. The image sensor comprises, a first substrate, a pixel array organized into a plurality of pixel subarrays, of which each pixel comprises a photoelectric element for integrating a photocharge during each one of a plurality of subframe exposures, a transfer gate and a buffered charge-voltage converter. A first charge accumulation element of the charge-voltage converter is operatively connectable to at least one second charge accumulation element through a gain switch. The image sensor comprises control circuitry configured to trigger a partial or a complete transfer of the and to time-interleave at least two rolling shutter control sequences. Separate readout blocks are provided on the second substrate for each pixel subarray, each comprising in a pipelined architecture an A/D conversion unit, a pixel memory logic and a pixel memory unit.

A time-of-flight distance measuring device divides a base exposure period into a plurality of sub exposure periods and holds without resetting an electric charge stored in the sub exposure period for a one round period which is one round of the plurality of sub exposure periods. The distance measurement value of short time exposure is acquired during the one round period and the distance measurement value of long time exposure is acquired during a plurality of the one round periods. Both of the distance measurement value of the long time exposure and the distance measurement value of the short time exposure can be acquired from the same pixel. With this, a dynamic range is expanded without being restricted by a receiving state of reflected light, optical design of received light, and an arrangement of pixels.