Anisotropic Channel Filtering
نویسندگان
چکیده
Channel smoothing is an alternative to diffusion filtering for robust estimation of image features. Its main advantages are speed, stability with respect to parameter changes, and a simple implementation. However, channel smoothing becomes instable in certain situations, typically for elongated, periodic patterns like for instance fingerprints. As for the diffusion filtering an anisotropic extension is required in these cases. In this paper we introduce a new method for anisotropic channel smoothing which is comparable to coherence enhancing diffusion, but faster and easier to implement. Anisotropic channel smoothing implements an orientation adaptive non-linear filtering scheme as a special case of adaptive channel filtering. The smoothing algorithm is applied to several fingerprint images and the results are compared to those of coherence enhancing diffusion.
منابع مشابه
Image Denoising Using Anisotropic Diffusion Equations on Reflection and illumination Components of Image
This paper proposes a new hybrid method based on Homomorphic filtering and anisotropicdiffusion equations for image denoising. In this method, the Homomorphic filtering extracts the reflectionand illumination components of a noisy image. Then a suitable image denoising method based onanisotropic diffusion is applied to each components with its special user-defined parameters .This hybridscheme ...
متن کاملEmpirical Mode Decomposition based Adaptive Filtering for Orthogonal Frequency Division Multiplexing Channel Estimation
This paper presents an empirical mode decomposition (EMD) based adaptive filter (AF) for channel estimation in OFDM system. In this method, length of channel impulse response (CIR) is first approximated using Akaike information criterion (AIC). Then, CIR is estimated using adaptive filter with EMD decomposed IMF of the received OFDM symbol. The correlation and kurtosis measures are used to sel...
متن کاملChannel Effect Compensation in OFDM System under Short CP Length Using Adaptive Filter in Wavelet Transform Domain
Channel estimation in communication systems is one of the most important issues that can reduce the error rate of sending and receiving information as much as possible. In this regard, estimation of OFDM-based wireless channels using known sub-carriers as pilot is of particular importance in frequency domain. In this paper, channel estimation under short cyclic prefix (CP) in OFDM system is con...
متن کاملChannel Estimation and CFO Compensation in OFDM System Using Adaptive Filters in Wavelet Transform Domain
Abstarct In this paper, combination of channel, receiver frequency-dependent IQ imbalance and carrier frequency offset estimation under short cyclic prefix (CP) length are considered in OFDM system. An adaptive algorithm based on the set-membership filtering (SMF) algorithm is used to compensate for these impairments. In short CP length, per-tone equalization (PTEQ) structure is used to avoid i...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2003