transform domain distributed video coding. outline another approach side information motion...

Transform Domain Distributed Video Coding

Outline

Another Approach Side Information Motion Compensation

Another Approach

8X8 DCT Divided into low frequency & high frequency Low frequency - Wyner-Ziv Coding High frequency - run-length & Huffman

High Frequency

Store quantized high frequency coefficient of previous frame

Calculate distance between previous frame and current frame

If the distance smaller than a threshold, send “no high frequency bits”

If the distance exceeds the threshold, compress coefficient using run-length and Huffman

Side information

Interpolation Extrapolation

Motion estimation Pixel value

Side InformationConventional

Intraframecodec

Extrapolation

Side Information

Wyner-Ziv Frame

Wyner-Ziv Frame

Reconstructed Key Frame

K1

S3

K1'

S2

Wyner-ZivDecoder

Reconstructed WZ Frame

S2'

Extrapolation

Key Frame

Wyner-ZivDecoder

Reconstructed WZ Frame

S3'S3

S2

Side InformationConventional

Intraframecodec

ConventionalIntraframe

codec

Interpolation

Interpolation

InterpolationWyner-Ziv

Decoder

Side Information

Side Information

Side Information

Key Frame

Key Frame

Wyner-Ziv Frame

Wyner-Ziv Frame

Wyner-Ziv Frame

Reconstructed WZ Frame

Reconstructed Key Frame

Reconstructed Key Frame

K1

K5

S2

S3

S4

K1'

K5'

S3'S3

S4

S2

Motion Compensation

Motion-compensated interpolation (MC-I)using the decoded Key frame at time t-1 & t+1

Estimate the motion

Key Frame Key Frame Wyner-ZivFrame

t+1t-1 t

Motion Compensation

)2

1,,(

K-S-K :Frame WZ1

'3

'12

^

321

KKMCIS

)3

2,,(

)3

1,,(

K-S-S-K :Frame WZ2

'4

'13

^

'4

'12

^

4321

KKMCIS

KKMCIS

)2

1,,(

)2

1,,(

)2

1,,(

K-S-S-S-K :Frame WZ3

'5

'34

^

'3

'12

^

'5

'13

^

54321

KSMCIS

SKMCIS

KKMCIS

Motion Compensation Motion-compensated extrapolation (MC-E)

estimate the motion between the Wyner-ziv frame at time t-2 and the Key frame at time t-1

Estimate the motion

Key Frame Wyner-ZivFrame

tt-2 t-1

Wyner-ZivFrame

Low complexity Motion Compensation

Average interpolation (Avg-I)side information generate by averaging the pixel value from the key frames at t-1 & t+1

Previous Frame Extrapolation (Prev-E)previous key frame is used directly as side information