Analysis of Affine Motion Compensated Prediction and its Application in Aerial Video Coding
Zusammenfassung
Kurzzusammenfassung:
This work deals with affine motion-compensated prediction (MCP) in video coding. Using the rate-distortion theory and the displacement estimation error caused by inaccurate motion parameter estimation, the minimum bit rate for encoding the prediction error is derived. Similarly, a 4-parameter simplified affine model as considered for the upcoming video coding standard VVC is analyzed. Both models provide valuable information about the minimum bit rate for encoding the prediction error as a function of the motion estimation accuracy.
Although the bit rate in MCP can be reduced by using a motion model capable of describing the motion in the scene, the total video bit rate may remain high. Thus, a codec independent coding system is proposed for aerial videos, which exploits the planarity of such sequences. Only new emerging areas and moving objects in each frame are encoded. From these, the decoder reconstructs a mosaic, from which video frames are extracted again. Th...
Schlagworte
- I–XVIII
- 1–10 1 Introduction 1–10
- 1.1 Motion-Compensated Prediction
- 1.2 Challenges for Aerial Surveillance Video Coding
- 1.2.1 Region of interest-based video coding
- 1.3 Contributions
- 1.4 Outline
- 11–36 2 Basics 11–36
- 2.1 SceneModel
- 2.2 CameraModel
- 2.2.1 Perspective projection
- 2.2.2 Lens model
- 2.2.3 Sensor model
- 2.2.4 Homogeneous coordinates
- 2.2.5 World coordinates to camera coordinates
- 2.3 Projective Transformation and Homography
- 2.4 Motion Estimation from Image Sequences
- 2.4.1 Feature detection
- 2.4.2 Correspondence analysis by Kanade-Lucas-Tomasi feature tracking
- 2.4.3 Outlier removal: random sample consensus (RANSAC)
- 2.5 Mosaicking of Aerial Videos
- 2.6 Hybrid Video Coding
- 2.6.1 Motion-compensated prediction
- 2.6.2 Global motion compensation
- 2.7 Rate-Distortion ¿eory
- 2.8 Region of Interest- (ROI-) based Video Coding
- 2.8.1 ROI definition and detection
- 2.8.2 ROI encoding
- 37–64 3 Rate-Distortion Theory for Affine Motion Compensation in Video Coding 37–64
- 3.1 Efficiency Analysis of Fully AffineMotion Compensation
- 3.1.1 Affine motion and error model
- 3.1.2 Probability density function of the displacement estimation error
- 3.1.3 Power spectral density of the signal
- 3.1.4 Power spectral density of the displacement estimation error
- 3.1.5 Rate-distortion function
- 3.1.6 Rate-distortion analysis of affine global motion-compensated prediction
- 3.1.7 Conclusions for the fully affine motion model for global motion compensation
- 3.2 Efficiency Analysis of Simplified AffineMotion Compensation
- 3.2.1 Derivation of the probability density function of the displacement estimation error for a simplified affine model
- 3.2.2 Rate-distortion analysis of the simplified affine model
- 3.3 Summary of AffineMotion-Compensated Prediction in Video Coding
- 65–86 4 ROI-based System for Low Bit Rate Coding of Aerial Videos 65–86
- 4.1 ROI: New Areas (NAs)
- 4.1.1 Calculation of the new areas
- 4.1.2 Long-term mosaicking of aerial videos
- 4.1.3 In-loop radial distortion compensation
- 4.2 ROI:Moving Objects (MOs)
- 4.2.1 Highly performant difference image-based moving object detection
- 4.3 ROI Coding of Aerial Video Sequences
- 4.3.1 Inherent noise removal of the proposed general ROI coding
- 4.4 Mosaicking of ROI-Encoded Videos
- 4.5 Video Reconstruction from ROI-Encoded Videos
- 87–116 5 Experiments 87–116
- 5.1 AffineMotion Compensation in Video Coding
- 5.1.1 Efficiency measurements for fully affine motion-compensated prediction in video coding
- 5.1.2 Operational rate-distortion diagrams using JEM
- 5.2 Evaluation of the ROI-based System for Low Bit Rate Aerial Video Coding
- 5.2.1 Objective evaluation of the general ROI-coding system compared to a modified HEVC-encoder and common HEVC coding
- 5.2.2 Subjective tests
- 5.2.3 Long-term mosaicking
- 117–132 6 Summary and Conclusions 117–132
- A Appendix
- A.1 Displacement Estimation Error pdf Derivation (Fully AffineModel)
- A.2 Displacement Estimation Error pdf Derivation (Simplified AffineModel)
- A.3 Fourier Transform of Displacement Estimation Error (Fully AffineModel)
- A.4 Fourier Transform of Displacement Estimation Error (Simplified AffineModel)
- 133–152 Bibliography 133–152
