Abstract: Techniques to temporally filter images via a filtering weight computation are disclosed. A first image having a first timestamp and a second image having a second timestamp are acquired. These images are generated by a camera, and the first timestamp is before the second timestamp. A motion compensation (MC) operation is performed on the first image to produce an MC image. A difference image is generated using the MC image and the second image. The difference image reflects differences in intensities that exist between the two images. A local weight map is generated based on those differences. A global weight map is generated based on certain IMU data. A final weight map is generated based on a combination of the local weight map and the global weight map. The final weight map is used to generate a filtered image.

Abstract: A system for dark current compensation in SPAD imagery is configurable to capture an image frame with the SPAD array and generate a temporally filtered image by performing a temporal filtering operation using the image frame and at least one preceding image frame. The at least one preceding image frame is captured by the SPAD array at a timepoint that temporally precedes a timepoint associated with the image frame. The system is also configurable to obtain a dark current image frame. The dark current image frame includes data indicating one or more SPAD pixels of the plurality of SPAD pixels that detect an avalanche event without detecting a corresponding photon. The system is also configurable to generate a dark current compensated image by performing a subtraction operation on the temporally filtered image or the image frame based on the dark current image frame.

Abstract: Digital image processing methods performed by a computer are disclosed. In one example, a first digital image captured by a real camera is sub-divided into a first plurality of sub-images. A second digital image captured by a real camera is sub-divided into a second plurality of sub-images. A set of image features in a first sub-image of the first plurality of sub-images is identified. A subset of neighboring sub-images is identified from the second plurality of sub-images based at least on each neighboring sub-image of the subset of neighboring sub-images having one or more corresponding image features in common with the set of image features identified in the first sub-image.

Abstract: Digital image processing methods performed by a computer are disclosed. In one example, a digital image captured by a real camera having intrinsic and extrinsic parameters is received. One or more distortion correction transformations are applied to the digital image to generate a distortion-corrected digital image. The distortion-corrected digital image is sub-divided into a plurality of distortion-corrected sub-images. For each distortion-corrected sub-image of the plurality of distortion-corrected sub-images, the distortion-corrected sub-image is associated with a synthesized recapture camera having synthesized intrinsic and extrinsic parameters mapped from the intrinsic and extrinsic parameters of the real camera.

Abstract: Techniques for generating a fused enhanced image. A first image is generated using a first camera of a first modality, and a second image is generated using a second camera of a second modality. Pixels that are common between the two images are identified. Textures for the common pixels are determined. A camera characteristic, which is linked to noise, is identified. A scaling factor is applied to the textures in the first image. A first saliency is determined using the scaled textures. A second saliency is determined using the textures from the second image. An alpha map is generated and reflects edge detection weights that have been computed for each one of the common pixels based on the two saliencies. Based on the alpha map, textures are merged from the common pixels to generate the fused enhanced image.

Abstract: Techniques for generating a temporally filtered image designed to compensate for global motions of a camera and to compensate for local motions of an object are disclosed. A history frame and a current frame are acquired. A global motion compensation operation is performed on the history frame to reproject a pose of the history frame to match the pose of the current frame. The history frame is compared against the current frame to identify pixels that represent moving objects. For each of those pixels, an optical flow vector is computed. The optical flow vectors are then applied to those pixels to shift those pixels to new locations. These new positions, which are in the history frame, correspond to positions that were identified in the current frame. Afterwards, the current frame is temporally filtered with the history frame.

Abstract: A system for regulating temporal filtering strength is configurable to: (i) obtain a light level indicator indicating light level associated with a real-world environment; (ii) determine a motion compensation confidence indicator using a current image and a previous image; (iii) determine a filter weight by processing the light level indicator and the motion compensation confidence indicator using a filter strength regulation module; and (iv) generate an output image by using at least the filter weight to filter a current frame with a previous frame.

Abstract: A system for adding persistence to SPAD imagery is configurable to capture, using a SPAD array, a plurality of image frames. The system is configurable to capture, using an IMU, pose data associated with the plurality of image frames. The pose data includes at least respective pose data associated with each of the plurality of image frames. The system is configurable to determine a persistence term based on the pose data. The system is also configurable to generate a composite image based on the plurality of image frames, the respective pose data associated with each of the plurality of image frames, and the persistence term. The persistence term defines a contribution of each of the plurality of image frames to the composite image.

Abstract: Techniques for aligning image content are disclosed. The alignment occurs by concurrently identifying corner and line features and by aligning the images based on those features. As a result, relaxed constraints can be used during the alignment process as compared to constraints that are required when aligning images using only corner features. To achieve these benefits, first and second images are acquired. A first set of pixels that correspond to corner features are detected within the images. In parallel, a second set of pixels that correspond to line features are detected within the images. Image content is then aligned from the two images. The aligning process is performed using at least some of the pixels from the first and second sets.

Abstract: A system for obtaining color imagery using SPADs includes a SPAD array that has a plurality of SPAD pixels. Each of the plurality of SPAD pixels includes a respective color filter positioned thereover. The system is configurable to capture an image frame using the SPAD array and generate a filtered image by performing a temporal filtering operation using the image frame and at least one preceding image frame. The at least one preceding image frame is captured by the SPAD array at a timepoint that temporally precedes a timepoint associated with the image frame. The system is also configurable to, after performing the temporal filtering operation, generate a color image by demosaicing the filtered image.

Abstract: A system for facilitating intensity image capture and time of flight capture. The system includes an image sensor array comprising a plurality of image sensor pixels, one or more processors, and one or more hardware storage devices storing instructions that are executable by the one or more processors to configure the system to facilitate intensity image capture and time of flight capture by configuring the system to perform interleaved intensity image capture and time of flight capture operations using the image sensor array.

Abstract: A system for generating high-resolution video from low-resolution images is configured to access a first video stream and a second video stream capturing an environment. The first video stream is captured by a first video capture device. The second video stream is captured by a second video capture device. Image frames of the first video stream are temporally synchronized with corresponding image frames of the second video stream. The system is also configured to generate a composite video stream with a higher resolution than the first or second video streams. Each composite image frame of the composite video stream is generated using a respective image frame of the first video stream and a temporally synchronized corresponding image frame of the second video stream as input.

Abstract: A system for facilitating tone mapping is configurable to (i) generate an input image histogram based on one or more input images, the input image histogram comprising a plurality of bins, wherein each bin of the plurality of bins is associated with one or more pixel values and indicates a quantity of pixels that comprise the one or more pixel values; (ii) generate a target histogram based at least on the input image histogram; and (iii) generate an output image by using the target histogram to map pixel values of at least one of the one or more input images to corresponding pixel values in the output image.

Abstract: A system for facilitating motion compensation is configurable to access an affine transformation-compensated image. The affine transformation-compensated image is generated by applying affine transformation-based motion compensation to a previous image. The system is further configurable to generate a motion-compensated image by applying optical flow-based motion compensation to the affine transformation-compensated image. The optical flow-based motion compensation utilizes the affine transformation-compensated image and a current image as inputs.

Abstract: A system for facilitating dark current compensation by weighted filtering is configurable to (i) receive an input dark current image; (ii) generate a corrected dark current image at least by scaling pixel values of the input dark current image based upon ambient light conditions; and generate a weight map comprising a weight value for each pixel of the corrected dark current image. For each pixel of the corrected dark current image, the weight value of the weight map may be based upon a light level of the pixel of the corrected dark current image. The system is also configurable to generate an output image by utilizing the weight map to filter an input image.

Abstract: A system for generating a dark current residual image is configurable to generate a weighted average image by: (i) determining a region-based weight value for each pixel of an input image based upon a light level of a region in which the pixel lies; and (ii) combining the input image with a previous image using the region-based weight values for each pixel of the input image. The system is also configurable to generate a dark current residual image based upon the weighted average image.

Abstract: A system for modifying a dark current image is configurable to receive an input image depicting a dark current state for one or more pixels of the input image, The dark current state for one or more pixels of the input image comprises one of: a faulty state or a non-faulty state. The system is configurable to partition the input image into a plurality of partitions and generate an updated input image by imposing at least one quantity constraint or at least one severity constraint to the plurality of partitions in association with at least one type of dark current state.

Abstract: A system for low compute high-resolution depth map generation using low-resolution cameras is configured to obtain a stereo pair of images and generate a depth map by performing stereo matching on the stereo pair of images. The system is also configured to obtain a first image comprising first texture information for the environment that has a first image resolution that is higher than an image resolution of images of the stereo pair of images. The system is further configured to generate a reprojected first image by reprojecting the first image to correspond to an image capture perspective associated with the depth map. The reprojection of the first image is based on depth information from the depth map and includes reprojected first texture information for the environment. The system is also configured to generate an upsampled depth map based on the depth map.

Abstract: A system for power efficient image acquisition is configurable to capture, using an image sensor, a plurality of partial image frames including at least a first partial image frame and a second partial image frame. The first partial image frame is captured at a first timepoint using a first subset of image sensing pixels of the plurality of image sensing pixels of the image sensor. The second partial image frame is captured at a second timepoint using a second subset of image sensing pixels of the plurality of image sensing pixels of the image sensor. The second subset of image sensing pixels includes different image sensing pixels than the first subset of image sensing pixels, and the second timepoint is temporally subsequent to the first timepoint. The system is configurable to generate a composite image frame based on the plurality of partial image frames.

Abstract: A computing system includes an illumination light source configured to emit illumination light into an external environment and an orientation sensor configured to estimate an orientation of the illumination light source relative to the external environment. The computing system includes a logic subsystem and a storage subsystem holding instructions executable by the logic subsystem to define a light restriction zone within the external environment. Based at least in part on the orientation of the illumination light source, the illumination light source is dynamically controlled to direct the illumination light toward at least a portion of the external environment outside the light restriction zone, while mitigating emission of the illumination light into the light restriction zone.