A method of reducing ringing artifacts in image data that has been filtered with a high frequency emphasis filter. For each filtered data value, a local variance is calculated from data values at neighboring filter taps. This variance is compared to a threshold, and if the threshold is ...
In signal processing, particularly digital image processing, ringing artifacts are artifacts that appear as spurious signals near sharp transitions in a signal. Visually, they appear as "rings" near edges; audibly, they appear as "echos" near transients, particularly sounds from percussion instruments...
Our post-processing scheme based on edge detection approach builds the ringing artifacts' map for each image. This map is used in the deringing routine. Experiment results show that the proposed framework can be used for the efficient removal of motion blur caused by camera shake. 1 broad ...
We present a new method to detect and remove ringing artifacts produced by the deconvolution process in image deblurring techniques. The method takes into account non-invertible frequency components of the blur kernel used in the deconvolution. Efficient Gabor wavelets are produced for each non-invert...
The performance of reducing ringing artifacts depends on the accurate classification of the local features in the image. The discrete wavelet transform (DWT) provides effective insight into both spatial and frequency characteristics of an image. Through the DWT analysis, we show that ringing artifacts...
Therefore, the spectrum of If will be a scaled version of I, i.e., If will be contrast reduced step edge function and there will be no ringing artifacts, which is consistent with our conclusion in the linear case. If f is a non-linear, Farid [5] proved using Taylor's series that ...
In the following post-processing stage, two kinds of low pass filters are adaptively applied according to the classified result on each block. It allows for strong low pass filtering in low-activity regions where the blocking artifacts are most noticeable, whereas it allows for weak low pass ...
Linear space-invariant image restoration algorithms often introduce ringing effects near sharp intensity transitions. It is shown that these artifacts are ... Lagendijk, R.L,J Biemond - 《IEEE Transactions on Acoustics Speech & Signal Processing》 被引量: 580发表: 1988年 ...
Blocking effect and ringing noise are two well-known artifacts in low bit rate coded video. The blocking effect is the grid noise along block boundaries mainly visible in smooth areas, and the ringing noise shows along object borders. Traditionally, de-blocking filters try to remove the unwanted...
K-space data truncation induces imaging artifacts in the form of Gibbs' ringing and has been one of the oldest, but also one of the toughest, problems to conquer in the practice of MR imaging, especially when the acquired image data matrix is small. Truncation artifacts arise in MR images ...