Abstract: A method of scanning a scene using an image sensor includes (a) dividing the scene into multiple first portions; and scanning a first portion for presence of objects in an object class. The method further includes continuing the scanning of the multiple first portions for presence of other objects in the scene. The method also selects a second portion of the scene, in response to detecting an object in the first portion; and then tracking the object in the selected second portion. The second portion of the scene is selected based on estimating motion of the object detected in the first portion, so that it may still be located in the second portion.

Abstract: Systems and methods for generating efficient transformed input image address sets for producing a multi-pane output image from an input image are disclosed. The input address sets may be generated by applying a first transformation corresponding to one pane of the output image to output pixel addresses to create first transformed input addresses, applying a second transformation corresponding to another pane to the output image pixel addresses to create second transformed input addresses, and storing, for one output pixel address, a first transformed image pixel address and a second transformed input pixel address and, for another output pixel address, including a first transformed input pixel address, but no second transformed address.

Abstract: Methods and apparatuses for providing dewarping and/or perspective correction of an input image are disclosed. Described embodiments include processing that provides dewarping and/or perspective correction by associating pixel values identified by input pixel addresses corresponding to an input image with output pixel addresses corresponding to an output image. An image processor having a storage circuit and an address mapping unit for determining a corresponding input pixel address from an output pixel address is also disclosed.

Abstract: Systems and methods are provided for detecting an object of object class, such as faces, in an image sensor. In some embodiments, the image sensor can provide a scan sequence that scans a scene over multiple time intervals. The image sensor can scan, in succession, portions of a scene, where each of the portions covers a different amount or location of the scene. This way, the scanned portions can be saved in an image buffer that is sized significantly smaller than an entire frame. In some embodiments, when the image sensor detects the presence of an object of the object class, the image sensor can store positional information (e.g., location and size of the object) in a region of interest buffer. The image sensor can output the positional information to aid an electronic device, such as a camera, perform various functions, such as automatic exposure and color balancing.

Abstract: Systems and methods are provided for detecting objects of an object class, such as faces, in an image sensor. In some embodiments, the image sensor can include a detector with an image buffer. The image buffer can store image data in raster order. The detector can read the data out in Z order to perform object detection. The image data can then compute feature responses using the Z-ordered image data and determine whether any objects of the object class are present based on the feature responses. In some embodiments, the detector can downscale the image data while the object detection is performed and use the downscaled image data to continue the detection process. In some embodiments, the image data can perform detection even if the image is rotated.

Abstract: Systems and methods for generating efficient transformed input image address sets for producing a multi-pane output image from an input image are disclosed. The input address sets may be generated by applying a first transformation corresponding to one pane of the output image to output pixel addresses to create first transformed input addresses, applying a second transformation corresponding to another pane to the output image pixel addresses to create second transformed input addresses, and storing, for one output pixel address, a first transformed image pixel address and a second transformed input pixel address and, for another output pixel address, including a first transformed input pixel address, but no second transformed address.

Abstract: A self calibrating stereo camera includes first and second spatial transform engines for directly receiving first and second images, respectively, of an object. The first and second spatial transform engines are coupled to a stereo display for displaying a fused object in stereo. A calibration module is coupled to the first and second spatial transform engines for aligning the first and second images, prior to display to a viewer. The first and second point extracting modules, respectively, receive the first and second images for extracting interest points from each image. A matching points module is coupled to the first and second point extracting modules for matching the interest points extracted by the first and second point extracting modules. The calibration module determines alignment error between the first and second images, in response to the interest point matches calculated by the matching points module.

Abstract: Image transforms that can be performed through a reverse lookup process in which output pixel addresses of an output image are reverse transformed into input pixel addresses. In some embodiments, rather than reverse transforming all output pixel addresses, a subset of output pixel addresses can be reverse transformed to calculate transformed addresses. The reverse transforms of all output pixel address may then be approximately calculated by interpolating the transformed addresses. The approximately transformed addresses can then be used as read addresses to a memory storing the input image.

Abstract: A variable rate image sensor outputs pixel data at a variable rate using lookup tables to selectively read out particular rows at particular times. The readout rate is not constant, allowing for a smaller image buffer in the overall system.

Abstract: A method of scanning a scene using an image sensor includes (a) dividing the scene into multiple first portions; and scanning a first portion for presence of objects in an object class. The method further includes continuing the scanning of the multiple first portions for presence of other objects in the scene. The method also selects a second portion of the scene, in response to detecting an object in the first portion; and then tracking the object in the selected second portion. The second portion of the scene is selected based on estimating motion of the object detected in the first portion, so that it may still be located in the second portion.

Abstract: Methods of calibrating a pixel correction function for compensating for vignetting in an optical device include exposing an optical device to a reference object in order to generate pixel data of at least part of an image of the reference object. A pixel correction function is provided including a first number of unknown constant values. Pixel data of a second number of sample points is provided from the pixel data of the at least part of the image. The second number is equal to the first number or the first number plus one. The constant values are determined using the pixel data of the second number of sample points. The method allows a pixel correction function to be calibrated with a small number of sample points, thereby simplifying calibration processes for individual optical devices, and thus reducing the manufacturing costs.

Abstract: Systems and methods are provided for detecting an object of object class, such as faces, in an image sensor. In some embodiments, the image sensor can provide a scan sequence that scans a scene over multiple time intervals. The image sensor can scan, in succession, portions of a scene, where each of the portions covers a different amount or location of the scene. This way, the scanned portions can be saved in an image buffer that is sized significantly smaller than an entire frame. In some embodiments, when the image sensor detects the presence of an object of the object class, the image sensor can store positional information (e.g., location and size of the object) in a region of interest buffer. The image sensor can output the positional information to aid an electronic device, such as a camera, perform various functions, such as automatic exposure and color balancing.

Abstract: Systems and methods are provided for detecting objects of an object class, such as faces, in an image sensor. In some embodiments, the image sensor can include a detector with an image buffer. The image buffer can store image data in raster order. The detector can read the data out in Z order to perform object detection. The image data can then compute feature responses using the Z-ordered image data and determine whether any objects of the object class are present based on the feature responses. In some embodiments, the detector can downscale the image data while the object detection is performed and use the downscaled image data to continue the detection process. In some embodiments, the image data can perform detection even if the image is rotated.

Abstract: Image transforms that can be performed through a reverse lookup process in which output pixel addresses of an output image are reverse transformed into input pixel addresses. In some embodiments, rather than reverse transforming all output pixel addresses, a subset of output pixel addresses can be reverse transformed to calculate transformed addresses. The reverse transforms of all output pixel address may then be approximately calculated by interpolating the transformed addresses. The approximately transformed addresses can then be used as read addresses to a memory storing the input image.

Abstract: A variable rate image sensor outputs pixel data at a variable rate using lookup tables to selectively read out particular rows at particular times. The readout rate is not constant, allowing for a smaller image buffer in the overall system.

Abstract: A processing system has a backlog of data caused by a difference between an input rate for receiving pixel data and a conversion rate for converting the pixel data to new pixel data. A dual buffer system associated with the processing system stores a minimum amount of unprocessed pixel data, required to perform an associated processing operation, in a first memory device and stores a backlog of the processed pixel data, after performing the associated processing operation, in a second memory device. The combined size of the first and second memory devices is less than the size that would otherwise be required to store the minimum amount of pixel data and the backlog of pixel data as unprocessed pixel data.

Abstract: Methods and apparatuses for providing dewarping and/or perspective correction of an input image are disclosed. Described embodiments include processing that provides dewarping and/or perspective correction by associating pixel values identified by input pixel addresses corresponding to an input image with output pixel addresses corresponding to an output image. An image processor having a storage circuit and an address mapping unit for determining a corresponding input pixel address from an output pixel address is also disclosed.

Abstract: An apparatus for determining a best number, representing a maximum or minimum of a set of numbers, includes a first comparator 3 having a latency of at least one clock cycle to compare a current number with a current best score and to output a corresponding first comparator signal 7 and at least a second comparator 13 having a latency of at least one clock cycle to compare the current number with any other input number compared with a current best number while the current number was being processed through the apparatus and to output at least a corresponding second comparator signal 18. A combinatorial logic block 15 receives the comparator signals and outputs a corresponding signal 20 dependent thereon and on a flag signal 21 received from flagging means arranged to flag whether the current best number was updated for one or more preceding input numbers while the current number was being processed.

Abstract: Methods of calibrating a pixel correction function for compensating for vignetting in an optical device include exposing an optical device to a reference object in order to generate pixel data of at least part of an image of the reference object. A pixel correction function is provided including a first number of unknown constant values. Pixel data of a second number of sample points is provided from the pixel data of the at least part of the image. The second number is equal to the first number or the first number plus one. The constant values are determined using the pixel data of the second number of sample points. The method allows a pixel correction function to be calibrated with a small number of sample points, thereby simplifying calibration processes for individual optical devices, and thus reducing the manufacturing costs.

Abstract: A method of obtaining a motion vector for a partition of a macroblock in block-based motion estimation by dividing macroblocks into partitions and determining a partition motion vectors for each partition. A best vector is selected for each partition from the partition motion vector for that partition and from vectors of partitions of neighbouring macroblocks.