1 outline introduction to jepg2000 why another image compression technique features discrete...
Post on 18-Dec-2015
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OutlineOutline
Introduction to JEPG2000Introduction to JEPG2000 Why another image compression Why another image compression techniquetechnique FeaturesFeatures
Discrete Wavelet TransformDiscrete Wavelet TransformWavelet transformWavelet transform Wavelet implementationWavelet implementation 5/3 lifting-based wavelet transform5/3 lifting-based wavelet transform Extension algorithmExtension algorithm
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Why New Encoder?Why New Encoder?
Low bit-rate compression Lossless and lossy compression in
one encoder Large image support Transmission in noisy
environments Non-natural image support
Computer generated image Compound documents Medical Images
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Features of JPEG2000 (1)Features of JPEG2000 (1)
Very low bit-rate compressionVery low bit-rate compression Lossy and lossless in one algorithmLossy and lossless in one algorithm Progressive transmissionProgressive transmission
Quality, Resolution, ComponentQuality, Resolution, Component
Error resilientError resilient Large imagesLarge images
JPEG at 0.125 bpp(192:1)
JPEG2000 at 0.125 bpp(192:1)
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Features of JPEG2000 (2)Features of JPEG2000 (2)
ROI: ROI: RRegion egion OOf f IInterestnterest Random code-stream access and Random code-stream access and
processprocess
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Encoder StructureEncoder Structure
QuantizationWavelet
TransformComponentTransform
Bit ModelingArithmetic
CodingData Ordering
Bit Allocation(Rate Control)
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Wavelet Transform over an Wavelet Transform over an Image InputImage Input
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Wavelet ImplementationWavelet Implementation
Convolution Based: Convolution Based: Area and time consumingArea and time consuming ComplicatedComplicated
Lifting Scheme: Lifting Scheme: Reduced memory requiredReduced memory required Lower computational complexityLower computational complexity
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Wavelet Transform in Wavelet Transform in JPEG2000JPEG2000
5/3 Transform: reversible5/3 Transform: reversible Integer to Integer transformInteger to Integer transform Can be used both for lossless or lossy Can be used both for lossless or lossy
codingcodingi0 i1 i2 i3 i4
h h
l
i0 i1 i2 i3 i4 i5 i6 i7 i9
hh
l
9/7 Transform: nonreversible9/7 Transform: nonreversible Real to Real transformReal to Real transform Can only be used for lossy codingCan only be used for lossy coding
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Proposed Architecture Proposed Architecture Data PathData Path
VerticalFunctional
Unit
Input 1
Input 2
Input 3
High 1
High 2
High
Low
Memory 1, )Input 1(
Memory 2, )Input 2(
Memory 3, )High 1(
1
2
3
4
Mem 1_out
Input
Mem 1_out
Input
Input
Input
High High
High
Mem 3_out
Mem 3_out
RegH1
RegH2 Horizontal
FunctionalUnit #1
High Buff 1
High Buff 2
Input 1
Input 2
Input 3
HH 1
HH 2
1
2
3
4
HH
LH
HH
HH Buff 1
HH
High
High
Reg
HH1
High Buff 1
HH Buff 1
HH
RegL1
RegL2 Horizontal
FunctionalUnit #2
Low Buff 1
Low Buff 2
Input 1
Input 2
Input 3
HL 1
HL 2
1
2
3
4
HL
LL
HL
HL Buff 1
HL
Low
Low
Reg
HL1
Low Buff 1
HL Buff 1
HL
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(5,3) Lifting Diagram(5,3) Lifting Diagram
Details
approximate
1/2
1/4
Y3
X3 X4 X5 X6 X7X2
Y7Y5
X8X1X0
Y1
Y2 Y4 Y6
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Extension AlgorithmExtension Algorithm
Applying the filter to the Applying the filter to the extremes of a streamextremes of a stream
Simple yet area and time Simple yet area and time consumingconsuming
Proposed ideaProposed idea
xx00 xx11 xx22 xx33 xx44 xx55 xx66
xx22 xx11 xx00 xx11 xx22 xx33 xx44 xx55 xx66 xx55 xx44
8-bit register
8-bit register
8-bit register
1 bitshifter
8-bit register
8-bit register
8-bit register
2 bitshifter
8-bit register
8-bit register
HighSample
SequentialInput
8-bit adder8-bit adder#1
8-bit subtractor#2
8-bit adder8-bit adder#3
8-bit adder8-bit adder#4
8-bit register
LowSample