In-Loop Filtering in Video Coding

 

Motivation

In many applications, the size of videos presents a challenge. Modern compression methods significantly reduce the size of videos without greatly compromising quality. However, the amount of video data and resolution have continuously increased in recent years. This makes efficient compression increasingly relevant to save costs for storage and transmission networks. This project focuses on the improvement of video codecs. Today’s compression methods encompass many steps, such as prediction, quantization, entropy coding, and in-loop filtering. The main focus of this project is in-loop filtering. The goal here is to perform filtering on encoded images of a video sequence to improve quality. The aim is to specifically reduce distortions that arise during the coding process to achieve an improvement in the signal.

Scientific Questions

  • How can existing prediction and in-loop filter techniques be improved?
  • How can statistical dependencies in images be exploited to achieve image enhancement?
  • Can coding information be used to locate and reduce artifacts?

Thesis Topics

New theses in the field of video coding are regularly advertised. In addition to the overall overview, there are also numerous topics that have not yet been advertised and can be presented in a personal conversation.

Contact

M.Sc.
Tim Classen
 +49 241 80 22906
 Tim.Classen@lfb.rwth-aachen.de

Publications

 
2026

Tim Classen and Mathias Wien
Enhanced GOP-Based RPR for Low-Complexity Video Coding
In: 2026 European Conference on Visual Information Processing EUVIP 2026 (EUVIP)

 
2026

Tim Classen and Mathias Wien
Sample-Adaptive Edge Enhancement Filtering for Adaptive Resolution Video Coding
In: IEEE International Workshop on Multimedia Signal Processing (MMSP)

2026

Priyanka Das, Tim Classen, Jan Schneider and Mathias Wien
Non-Rectangular Transform Coding in AV1 using Shape-Adaptive DCT
In: European Conference onVisual Information Processing (EUVIP)

2026

Priyanka Das, Oguzhan Yueksel, Jan Schneider, Tim Classen and Mathias Wien
Graph Fourier Transforms for Non-Rectangular Residual Coding for AV1 Wedge Modes
In: European Signal Processing Conference (EUSIPCO)

2026

Priyanka Das, Tim Classen and Mathias Wien
Entropy Coding for Non-Rectangular Transform Blocks using Partitioned DCT Dictionaries for AV1
In: Data Compression Conference (DCC)

2025

Tim Classen, Xiang Li, Priyanka Das and Mathias Wien
Loop Filters and Edge Enhancement for Variable Resolution Video Coding
In: 2025 Picture Coding Symposium (PCS)

2025

Priyanka Das, Xiaoqing Zhu, Tim Classen and Mathias Wien
Parameter Dependent Wedge Boundary Switching in AVM
In: Visual Communications and Image Processing (VCIP)

2025

Priyanka Das, Tim Classen and Mathias Wien
Adaptive Smoothing Of Non-rectangular Prediction Block Edges In The Wedge Mode Of AVM
In: 2025 IEEE International Conference on Image Processing (ICIP)

2024

Nicolas Neumann, Priyanka Das, Tim Classen and Mathias Wien
Fast Template Matching-Based Reference Picture Padding for Video Coding
In: 2024 IEEE International Conference on Image Processing (ICIP)

2023

Tim Classen and Mathias Wien
Weighted Edge Sharpening Filtering for Upscaled Content in Adaptive Resolution Coding
In: 2023 IEEE International Conference on Visual Communications and Image Processing (VCIP)