# US 2021/0279897 A1 · Response normalization for overlapped multi-image applications > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0279897 A1 - Document ID: US20210279897A1 - Status: Published application - Kind: A1 - Application number: 17/313,612 - Filed: 2021-05-06 - Published: 2021-09-09 - Earliest claimed: 2018-11-06 - Assignees: FLIR Commercial Systems, Inc. - Applicants: FLIR Commercial Systems, Inc. - Inventors: Enrique Sanchez-Monge; Alessandro Foi; Michael Kent - Web page: https://patentgrep.com/patent/US20210279897A1 ## CPC - G06T 7/337: {involving reference images or patches} - G06T 3/40: Scaling of whole images or parts thereof, e.g. expanding or contracting - G06T 5/40: using histogram techniques - G06T 5/50: using two or more images, e.g. averaging or subtraction - G06T 5/80: Geometric correction - G06T 5/90: Dynamic range modification of images or parts thereof - G06T 5/94: based on local image properties, e.g. for local contrast enhancement - G06T 7/30: Determination of transform parameters for the alignment of images, i.e. image registration - G06T 2207/10032: Satellite or aerial image; Remote sensing - G06T 2207/10048: Infrared image - G06T 2207/20016: Hierarchical, coarse-to-fine, multiscale or multiresolution image processing; Pyramid transform - G06T 2207/20221: Image fusion; Image merging - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL ## Abstract Systems and methods for registration of image pairs, including camera response function normalization are disclosed and include selecting a pair of images from a set of images, each of the pair of images having associated metadata, determining a camera response function for each of the images in the pair of images using the associated metadata, normalizing each camera response function for across the set of images, and applying the normalized camera response function to the pair of images. A deformation map is generated in a multi-scale process using registration parameters, to deform one of the pair of images to align with another of the pair of images. The image pairs may be selected by identifying image pairs having an overlap that exceeds an overlap threshold, having a sequential proximity in an image series satisfying a proximity threshold, and/or having estimated image capture attitudes within an attitude threshold. ## Claims ### Claim 1 A method comprising: selecting a pair of images from a set of images, each of the pair of images having associated meta data; determining a camera response function for each of the images in the pair of images using the associated meta data; normalizing each camera response function for across the set of images; and applying the normalized camera response function to the pair of images. ### Claim 2 (depends on 1) The method of claim 1, wherein the pair of images comprises infrared images. ### Claim 3 (depends on 1) The method of claim 1, further comprising normalizing a dynamic range of each of the pair of images. ### Claim 4 (depends on 1) The method of claim 1, further comprising applying at least one lens distortion correction model to each image in the pair of images. ### Claim 5 (depends on 1) The method of claim 1, further comprising demixing each of the images from the pair of images to remove low-frequency non-uniformity. ### Claim 6 (depends on 1) The method of claim 1, further comprising creating a deformation map using registration parameters, wherein the deformation map is used to deform one of the pair of images to align with another of the pair of images. ### Claim 7 (depends on 6) The method of claim 6, wherein creating the deformation map further comprises a multi-scale process comprising resizing the pair of images to a current processing scale of the multi-scale process. ### Claim 8 (depends on 7) The method of claim 7, wherein the multi-scale process further comprises, after resizing the pair of images to a current processing scale of the multi-scale process, optimizing parameters for the resized images, applying the camera response function, and deforming the resized images. ### Claim 9 (depends on 8) The method of claim 8, wherein the multi-scale process further comprises updating the deformation map in accordance with an error histogram. ### Claim 10 (depends on 1) The method of claim 1, wherein selecting the pair of images from the set of images comprises: identifying image pairs having an overlap that exceeds an overlap threshold, having a sequential proximity in an image series satisfying a proximity threshold, and/or having estimated image capture attitudes within an attitude threshold. ### Claim 11 A system comprising: a processor; and a local memory operable to store a plurality of machine readable instructions which when executed by the processor are operable to cause the system to perform steps comprising: selecting a pair of images from a set of images, each of the pair of images having associated meta data; determining a camera response function for each of the images in the pair of images using the associated meta data; normalizing each camera response function for across the set of images; and applying the normalized camera response function to the pair of images. ### Claim 12 (depends on 11) The system of claim 11, wherein the pair of images comprises infrared images. ### Claim 13 (depends on 11) The system of claim 11, wherein the plurality of machine readable instructions, when executed by the processor, are further operable to cause the system to perform steps comprising: normalizing a dynamic range of each of the pair of images. ### Claim 14 (depends on 11) The system of claim 11, wherein the plurality of machine readable instructions, when executed by the processor, are further operable to cause the system to perform steps comprising: applying at least one lens distortion correction model to each image in the pair of images. ### Claim 15 (depends on 11) The system of claim 11, wherein the plurality of machine readable instructions, when executed by the processor, are further operable to cause the system to perform steps comprising: demixing each of the images from the pair of images to remove low-frequency non-uniformity. ### Claim 16 (depends on 11) The system of claim 11, wherein the plurality of machine readable instructions, when executed by the processor, are further operable to cause the system to perform steps comprising: creating a deformation map using registration parameters, wherein the deformation map is used to deform one of the pair of images to align with another of the pair of images. ### Claim 17 (depends on 16) The system of claim 16, wherein creating the deformation map further comprises a multi-scale process comprising resizing the pair of images to a current processing scale of the multi-scale process. ### Claim 18 (depends on 17) The system of claim 17, wherein the multi-scale process further comprises, after resizing the pair of images to a current processing scale of the multi-scale process, optimizing parameters for the resized images, applying the camera response function, and deforming the resized images. ### Claim 19 (depends on 18) The system of claim 18, wherein the multi-scale process further comprises updating the deformation map in accordance with an error histogram. ### Claim 20 (depends on 11) The system of claim 11, wherein selecting the pair of images from the set of images comprises identifying image pairs having an overlap that exceeds an overlap threshold, having a sequential proximity in an image series satisfying a proximity threshold, and/or having estimated image capture attitudes within an attitude threshold.