Constant Bracket High Dynamic Range (cHDR) Operations

摘要

Systems, methods, and computer readable media to capture and process high dynamic range (HDR) images when appropriate for a scene are disclosed. When appropriate, multiple images at a single—slightly underexposed—exposure value are captured (making a constant bracket HDR capture sequence) and local tone mapping (LTM) applied to each image. Local tone map and histogram information can be used to generate a noise-amplification mask which can be used during fusion operations. Images obtained and fused in the disclosed manner provide high dynamic range with improved noise and de-ghosting characteristics.

主权项

1. A method to capture an image, comprising:
obtaining a first exposure value for an image capture device, wherein the first exposure value is adapted to under-expose a scene relative to a neutral exposure value; capturing, using the image capture device, a plurality of images of the scene at the first exposure value; obtaining, for each of the plurality of images, a corresponding tone map; applying each tone map to its corresponding image to generate a corresponding plurality of tone mapped images; generating a mask for each tone mapped image based on the tone map of each tone mapped image's corresponding image; fusing two or more of the tone mapped images, based on each tone mapped image's mask, to generate a high dynamic range (HDR) composite image; and storing the HDR composite image in a memory.