transform domain distributed video coding. outline another approach side information motion...
Post on 21-Dec-2015
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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