Interframe Wavelet Coding

The Status of Interframe Wavelet Coding Exploration in MPEG

ISO/IEC JTC1/SC29/WG11MPEG2002/N4928

Klagenfurt, July 2002

Adaptive Motion-Compensated Wavelet Filtering for Image Sequence Coding

IEEE TRANSACTIONS ON IMAGE PROCESSINGVOL. 6, NO. 6, JUNE 1997

Jean-Pierre Leduc, Jean-Marc Odobez, and Claude Labit

Outline

Wavelet transform-based coding Motion Compensated Temporal

Filtering(MCTF) Block Diagram of Interframe Wavelet Experimental results Conclusions

Wavelet transform-based coding

Discrete wavelet transform(DWT) decomposes a nonstationary signal

into multiscaled subbands

(1) Wavelet transform

(2) Quantization

(3) Entropy coding

Motion Compensated Temporal Filtering(MCTF) The spatio-temporal scenes will be

segmented according to motionbuild the trajectories by a spatio-temporal segmentation

algorithm and a related trajectory construction

Temporal filtering will applied along the assumed motion trajectories

Motion Compensated Temporal Filtering(MCTF)

(Haar filter [1, 1] [1, -1])

(Haar filter [1, 1] [1, -1]) with motion compensation

Motion Compensated 3D Wavelet Coding by Lifting Filter Implementation

The “highpass” pictures are very much the same as difference frame in a frame prediction

can be achieved in combination with motion compensation

A “lifting filter” structure is an efficient implementation of wavelet decomposition

Consiting of a “prediction step”(highpass filter) and an “update step”(lowpass filter)

An MCTF four-level decomposition (GOP=16 frames)

Divides consecutive frames into groups(GOP=16)

Perform MC filtering on pairs of frames to produce temporal low and high frames.

Temporal low frames decomposed again with the same MC filtering

A three-level 3D motion compensated decomposition

Pictures at leaves of tree are subject to spatial wavelet decomposition

H

LH

LLL LLH

video sequence

1st temporal level

2nd temporal level

3rd temporal level

Block Diagram of Interframe Wavelet

Experimental Results

Examples of comparison between MCTF and AVC (GOP=16 frames)

Conclusions

Scalability : spatial, temporal, SNR and complexity(Wavelet coding which inherently possess scalability)

Providing flexible scalability of a single bitstream(encoding once,decoding multiple times)

Error resilience(a non-recursive coder)