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Transform Domain Distributed Video Coding
13

Transform Domain Distributed Video Coding. Outline Another Approach Side Information Motion Compensation.

Dec 21, 2015

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Page 1: Transform Domain Distributed Video Coding. Outline  Another Approach  Side Information  Motion Compensation.

Transform Domain Distributed Video Coding

Page 2: Transform Domain Distributed Video Coding. Outline  Another Approach  Side Information  Motion Compensation.

Outline

Another Approach Side Information Motion Compensation

Page 3: 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

Page 4: Transform Domain Distributed Video Coding. Outline  Another Approach  Side Information  Motion Compensation.
Page 5: Transform Domain Distributed Video Coding. Outline  Another Approach  Side Information  Motion Compensation.

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

Page 6: Transform Domain Distributed Video Coding. Outline  Another Approach  Side Information  Motion Compensation.

Side information

Interpolation Extrapolation

Motion estimation Pixel value

Page 7: Transform Domain Distributed Video Coding. Outline  Another Approach  Side Information  Motion Compensation.

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

Page 8: Transform Domain Distributed Video Coding. Outline  Another Approach  Side Information  Motion Compensation.

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

Page 9: Transform Domain Distributed Video Coding. Outline  Another Approach  Side Information  Motion Compensation.

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

Page 10: Transform Domain Distributed Video Coding. Outline  Another Approach  Side Information  Motion Compensation.

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

Page 11: Transform Domain Distributed Video Coding. Outline  Another Approach  Side Information  Motion Compensation.

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

Page 12: Transform Domain Distributed Video Coding. Outline  Another Approach  Side Information  Motion Compensation.

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

Page 13: Transform Domain Distributed Video Coding. Outline  Another Approach  Side Information  Motion Compensation.