Flicker Suppression in JPEG2000 using Segmentation-Based Adjustment of Block Truncation Lengths

Abstract

Flickering is a temporal visual artifact that affects compressed video. It is prominent in intra-frame video coders and is largely the result of content variations and quantization. We concentrate on flickering due to quantization. JPEG2000 uses Post-Compression Quantization which is applied through the EBCOT algorithm. EBCOT has been found, however, to cause significant flickering in the reconstructed video. In this work, we evaluate existing flicker metrics, investigate the causes of flicker, and propose a new rate-distortion optimal algorithm that suppresses flicker. The proposed algorithm suppresses temporal flicker at a negligible cost in spatial image quality.

Adaptive Fuzzy Filtering for Artifact Reduction in Compressed images and videos

“…Furthermore, the fuzzy MCSTF filter should apply strongest filtering to the pixels in surrounding motion compensated frames at the same spatial position due to their strongest correlation to I' [t,m,n] and weaker in other positions. Based on the cross-correlation value of pixels in the windows of the current frame and its surrounding frames, the scaling factor of the spread parameter is determined by (14) where (15) (16) and (17) where V is a spatial window centered on the pixel of interest I' [t,m,n] of the current frame or I' [t+t',m+m',n+n'] of the surrounding frames. Higher correlation between the pixels in the 2 windows leads to more contribution to the output of the pixel at [t',m',n'].…”

“…Previous flickering metrics focused on flickering artifacts of intra frame coding in H.264 [3] and Motion JPEG2000 [14]. In [3], the flickering of the [i,j] th block was calculated by the sum of square difference (SSD) between the temporal flickering in the original frames and compressed frames O and compressed frames I (19) Where (20) The metric S for the whole frame only took into account the blocks with small temporal SSD value in the original sequence (21) where L was the number of blocks in frame t which satisfy SSD org [t,i,j] ≤ ε SSD org .…”

“…To validate the effectiveness of the proposed flickering metric, the metrics in [3] and [14] and the proposed metric is applied to the compressed and enhance Mobile sequences. These results are shown in Figure 17.…”

“…A normalized metric should be considered to make it comparable for different blocks, different frames or different sequences. In [14], the metric applied the SSD operator to the metric proposed by [17]. These SSDs between the original and compressed blocks were calculated separately for the current and the previous frames.…”

Reduction of Artifacts in Compressed Videos using Adaptive Fuzzy Filter and Bilateral Filter and Comparison of their Performance

“…In [6], flickering artefact term is used to find the optimal prediction and block size mode for intra-frame coding. A similar method was introduced in [7] for flickering reduction in Motion JPEG 2000. In [8] the spatiotemporal median filter for non-motion blocks was used to deal with characteristics of mosquito artifacts and this method cannot achieve better enhancement.…”