Local Definition of Global Image Transformations
AssigneeDolby Laboratories Licensing Corporation
InventorsAnders Ballestad, Gerwin Damberg
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Abstract
A global image adjustment, such as dynamic range adjustment is established based on image characteristics. The image adjustment is based more heavily on pixel values in image areas identified as being important by one or more saliency mapping algorithms. In one application to dynamic range adjustment, a saliency map is applied to create a weighed histogram and a transformation is determined from the weighted histogram. Artifacts typical of local adjustment schemes may be avoided.
Claims23
A method for adjusting image data defining an image, the method comprising:
- generating a saliency map for the image;
- establishing a global transformation based on the image data wherein establishing the global transformation comprises ignoring parts of the image data corresponding to image areas indicated by the saliency map as having low saliency or weighing parts of the image data corresponding to image areas indicated by the saliency map as having low saliency less heavily than other parts of the image data corresponding to image areas indicated by the saliency map as having higher saliency;
- and
- applying the global transformation to the image data.
A method for adjusting image data defining an image, the method comprising:
- generating a saliency map for the image;
- generating a weighted histogram for the image by, for pixels in the image, adding values for the pixels from the saliency map to bin values for bins corresponding to pixel values for the pixels;
- generating a global transformation based on the weighted histogram;
- and
- applying the global transformation to globally adjust the image data.
Dependencies are inferred from the claim text.