Patent ID: 9424632
Filing Date: 2016-08-23
CPC Classification: G06T,H04N

Claim Text:
1. A method, comprising: obtaining a plurality of images of a scene captured using a camera sensor at one or more exposure values with a pre-determined camera response curve; selecting one of the obtained images as a reference image; obtaining a set of mapped images by mapping each pixel intensity value to a corresponding irradiance value in each obtained image using the pre-determined camera response curve and a relative exposure value of each obtained image with respect to the exposure value of the selected reference image; determining a pixel intensity value dependent weighting factor based on the pre-determined camera response curve for each possible pixel intensity value in the obtained images; identifying a first set of images from the mapped images, excluding the mapped reference image, for a plurality of mapped pixels in the reference image based on the pixel intensity value and a relative exposure value of each mapped image with respect to the reference image; establishing a set of corresponding mapped pixels for the plurality of mapped pixels in the reference image in each of the identified first set of images; computing a similarity measure for the plurality of mapped pixels of the reference image and the established corresponding mapped pixels in each of the identified first set of images; finalizing a subset of the established corresponding mapped pixels in the identified first set of images that are used for combining with the plurality of mapped pixels of the reference image based on a comparison between the established corresponding mapped pixel's intensity value in a given image in the identified first set of images and a pixel intensity value range computed as a function of the mapped pixel's intensity value in the reference image, the pre-determined camera response curve, and the relative exposure of the given image in the identified first set of images with respect to the exposure value of the reference image; and generating a high dynamic range (HDR) image by combining each of the plurality of mapped pixels of the reference image with the subset of its established corresponding mapped pixels in the identified first set of images for that mapped pixel of the reference image based on the computed similarity measures for that mapped pixel of the reference image and the determined pixel intensity value dependent weighting factors for the mapped pixel's intensity value of the reference image and each of the subset of corresponding mapped pixel's intensity value in each of the identified first set of images, wherein the generated HDR image having a dynamic range higher than dynamic range of each of the plurality of images of the scene obtained from the camera sensor.