公开(公告)号：US11094039B1

公开(公告)日：2021-08-17

申请号：US16563410

申请日：2019-09-06

Applicant: Apple Inc.

Inventor： Tak Shing Wong ,  Gijesh Varghese ,  Farhan A. Baqai ,  Wu Cheng ,  Hao Sun

IPC: G06K9/00 ,  G06T5/00 ,  G06T5/50

Abstract: Devices, methods, and computer-readable media describing an adaptive approach for image selection, fusion, and noise reduction, e.g., to generate low noise and high dynamic range (HDR) images with improved motion freezing in a variety of capturing conditions. An incoming image stream may be obtained from an image capture device, wherein the image stream comprises a variety of differently-exposed captures, e.g., EV0 images, EV− images, EV+ images. When a capture request is received, a set of rules may be used to evaluate one or more capture conditions associated with the images from the incoming image stream and determine which two or more images to select for a fusion operation. The fusion operation may be designed to adaptively fuse the selected images, e.g., in a fashion that is determined to be optimal from a noise variance minimization standpoint. A fusion-adaptive noise reduction process may further be performed on the resultant fused image.

公开(公告)号：US09641820B2

公开(公告)日：2017-05-02

申请号：US14872098

申请日：2015-09-30

Applicant: Apple Inc.

Inventor： Farhan A. Baqai ,  Fabio Riccardi ,  Russell A. Pflughaupt ,  Claus Molgaard ,  Gijesh Varghese

IPC: H04N9/77 ,  H04N9/64 ,  H04N9/67 ,  H04N9/73 ,  H04N9/69

CPC classification number: H04N9/77 ,  G06K9/40 ,  G06T5/002 ,  G06T5/009 ,  G06T5/20 ,  G06T5/50 ,  G06T2207/10024 ,  G06T2207/20016 ,  G06T2207/20182 ,  G06T2207/20208 ,  G06T2207/20221 ,  H04N5/208 ,  H04N5/217 ,  H04N9/646 ,  H04N9/67 ,  H04N9/69 ,  H04N9/73

Abstract: Techniques for de-noising a digital image using a multi-band noise filter and a unique combination of texture and chroma metrics are described. A novel texture metric may be used during multi-band filter operations on an image's luma channel to determine if a given pixel is associated with a textured/smooth region of the image. A novel chroma metric may be used during the same multi-band filter operation to determine if the same pixel is associated with a blue/not-blue region of the image. Pixels identified as being associated with a smooth blue region may be aggressively de-noised and conservatively sharpened. Pixels identified as being associated with a textured blue region may be conservatively de-noised and aggressively sharpened. By coupling texture and chroma constraints it has been shown possible to mitigate noise in an image's smooth blue regions without affecting the edges/texture in other blue objects.