Ali Radmehr | Isfahan University of Technology (original) (raw)

Ali Radmehr

Address: Iran, Islamic Republic of

less

Related Authors

Athanassios Skodras

Manoj Sharma

Rony Kassam

Dr. MATHIVANAN PONNAMBALAM

Adnan Gutub

Adnan Gutub

Umm Al-Qura University, Makkah, Saudi Arabia

Uploads

Papers by Ali Radmehr

Research paper thumbnail of PCA-based hierarchical clustering approach for motion vector estimation in H.265/HEVC video error concealment

Multimedia Tools and Applications

Research paper thumbnail of Gaussian mixture based generative approach for H.265/HEVC error concealment

Zenodo (CERN European Organization for Nuclear Research), Nov 29, 2022

Research paper thumbnail of Error concealment via particle filter by Gaussian mixture modeling of motion vectors for H.264/AVC

Signal, Image and Video Processing, 2015

We use particle filtering for correcting the erroneous Motion Vectors (MVs) which are derived fro... more We use particle filtering for correcting the erroneous Motion Vectors (MVs) which are derived from the Boundary Matching Algorithm (BMA) in packet video communications. Assuming a two-state Markov channel model for transmission, the error of the extracted MVs by BMA is shown to be modeled by the Gaussian Mixture (GM) distribution. Formulating the problem in the state-space, we deploy particle filtering for denoising the erroneous MVs. The main challenge of using particle filters is high computational complexity that is directly related to the number of particles. The proposed particle filtering scheme is efficient even if the number of particles is decreased. Experimental results are provided to show the efficiency of this filtering approach compared to a recent scheme based on Kalman filtering. The experiments show meaningful increase in the quality of the recovered video sequences in terms of PSNR up to 3 dB compared with the other error concealment (EC) techniques. Also, the computational complexity of the proposed scheme is discussed.

Research paper thumbnail of A novel video error concealment technique using modified boundary matching algorithm with correlation function

2013 21st Iranian Conference on Electrical Engineering (ICEE), 2013

Video transmission over wireless networks becomes a major part of multimedia studies especially a... more Video transmission over wireless networks becomes a major part of multimedia studies especially after fourthgeneration communication standard has been introduced. There is a growing need to improve video visual quality, while its computational complexity should remain low. A low-complexity Error Concealment (EC) method for missing macroblock (MB) recovery is Boundary Matching Algorithm (BMA). Nevertheless, this method suffers from lack of accuracy. In this paper, we propose a novel modified BMA method by exploiting the correlation of the pixels on the edge of the missing MB. The performance of this method is explained in detail and extra experiment results are given to demonstrate its superiority over BMA method.

Research paper thumbnail of A novel video error concealment technique based on Gaussian window analysis

2014 22nd Iranian Conference on Electrical Engineering (ICEE), 2014

Error Concealment (EC) algorithms have provided a very useful tool for concealing the errors in d... more Error Concealment (EC) algorithms have provided a very useful tool for concealing the errors in digital video streams. The importance of EC methods arises specially in broadcasting and multicasting communications where retransmission of corrupted video sequence is not possible. In this paper, a Motion Vector (MV) space is proposed around each erroneous macroblock (MB) and thus the candidate MV can be refined using a Gaussian window effectively. Gaussian window application in this scenario is analyzed in detail. Finally, simulation results proves the superiority of the proposed method to the conventional approaches.

Research paper thumbnail of PCA-based hierarchical clustering approach for motion vector estimation in H.265/HEVC video error concealment

Multimedia Tools and Applications

Research paper thumbnail of Gaussian mixture based generative approach for H.265/HEVC error concealment

Zenodo (CERN European Organization for Nuclear Research), Nov 29, 2022

Research paper thumbnail of Error concealment via particle filter by Gaussian mixture modeling of motion vectors for H.264/AVC

Signal, Image and Video Processing, 2015

We use particle filtering for correcting the erroneous Motion Vectors (MVs) which are derived fro... more We use particle filtering for correcting the erroneous Motion Vectors (MVs) which are derived from the Boundary Matching Algorithm (BMA) in packet video communications. Assuming a two-state Markov channel model for transmission, the error of the extracted MVs by BMA is shown to be modeled by the Gaussian Mixture (GM) distribution. Formulating the problem in the state-space, we deploy particle filtering for denoising the erroneous MVs. The main challenge of using particle filters is high computational complexity that is directly related to the number of particles. The proposed particle filtering scheme is efficient even if the number of particles is decreased. Experimental results are provided to show the efficiency of this filtering approach compared to a recent scheme based on Kalman filtering. The experiments show meaningful increase in the quality of the recovered video sequences in terms of PSNR up to 3 dB compared with the other error concealment (EC) techniques. Also, the computational complexity of the proposed scheme is discussed.

Research paper thumbnail of A novel video error concealment technique using modified boundary matching algorithm with correlation function

2013 21st Iranian Conference on Electrical Engineering (ICEE), 2013

Video transmission over wireless networks becomes a major part of multimedia studies especially a... more Video transmission over wireless networks becomes a major part of multimedia studies especially after fourthgeneration communication standard has been introduced. There is a growing need to improve video visual quality, while its computational complexity should remain low. A low-complexity Error Concealment (EC) method for missing macroblock (MB) recovery is Boundary Matching Algorithm (BMA). Nevertheless, this method suffers from lack of accuracy. In this paper, we propose a novel modified BMA method by exploiting the correlation of the pixels on the edge of the missing MB. The performance of this method is explained in detail and extra experiment results are given to demonstrate its superiority over BMA method.

Research paper thumbnail of A novel video error concealment technique based on Gaussian window analysis

2014 22nd Iranian Conference on Electrical Engineering (ICEE), 2014

Error Concealment (EC) algorithms have provided a very useful tool for concealing the errors in d... more Error Concealment (EC) algorithms have provided a very useful tool for concealing the errors in digital video streams. The importance of EC methods arises specially in broadcasting and multicasting communications where retransmission of corrupted video sequence is not possible. In this paper, a Motion Vector (MV) space is proposed around each erroneous macroblock (MB) and thus the candidate MV can be refined using a Gaussian window effectively. Gaussian window application in this scenario is analyzed in detail. Finally, simulation results proves the superiority of the proposed method to the conventional approaches.

Log In