Based on this partition, for the directional featured region, we design corresponding filter orientation and thresholds to best preserve image details while reducing blocking artifacts; for the consecutive non-featured region, we impose extra smoothing to suppress the visually severe blocking artifacts.
Other encoders have the tendency to overly reallocate from large flat areas which can introduce blocking artifacts to the image.
It is based on three characteristics of perceivable blocking artifacts, the strength of the block boundaries, the discontinuities across the block boundaries and the flatness of the image.
To develop the new NR image quality metric, images were first classified into two classes: one that contained blocking artifacts, and the other that contained no blocking artifacts.
There are much fewer block artifacts on the face and building in the decoded frame (Figure 7 e)) when compared to the proposed method by the TDWZ (Figure 7 d)).
It can be seen that both UEPWZ and CAUEP produce block artifacts on the left and right cheeks of the person in the figure, with CAUEP generating less artifacts than UEPWZ.
The reconstructed images from highly compressed data have noticeable image degradations, such as blocking artifacts near the block boundaries.
The metric calculated only at the detected blocking artifacts is averaged over all blocking artifacts in the image to yield an overall blockiness score.
The proposed algorithm removes blocking artifacts in the RGB domain instead of YCbCr; therefore, it can simultaneously eliminate blocking artifacts from two components.
Then, to compute the proposed NR quality metric, the blocking metric was used for images containing blocking artifacts, and the blur metric was used for those containing no blocking artifacts, respectively.
