Method and device for calculating blur in video images

摘要

Blur is one of the most important features related to image quality. Accurately estimating the blur level of an image is a great help to accurately evaluate its quality. A method for calculating blur of video images comprises calculating a horizontal blur value, and determining characteristic parameters of the video images, including at last progressive/interlaced and spatial resolution level. If the video images are progressive, also a vertical blur value is calculated, and combined with the horizontal blur value. The next step is normalizing the horizontal blur value, or the combined horizontal and vertical blur value, according to predefined min and max values, wherein the min and max values are adapted to the spatial resolution level.

主权项

1. A method for calculating blur of video images, comprising steps of
calculating a horizontal blur value; determining characteristic parameters of the video images, including at least progressive/interlaced and spatial resolution level; if the video images are progressive, calculating also a vertical blur value and combining it with the horizontal blur value; and normalizing the horizontal blur value, or the combined horizontal and vertical blur value, according to predefined minimum and maximum values, wherein the minimum and maximum values are adapted to the spatial resolution level, wherein calculating a blur value comprises calculating a local variance around a current pixel and wherein the current pixel is excluded from blur cancellation if the local variance is above a maximum threshold or below a minimum threshold.