1

IP P

rote

ctio

n fo

r FIR

Filt

er

FPG

A Im

plem

enta

tion

Wei

Dai

Dep

t of E

CE,

Uni

vers

ity o

f Win

dsor

Supe

rvis

or :

Dr.H

.K.K

wan

& D

r H.W

uM

ay.2

004

2

Out

line

1.In

trodu

ctio

n to

Dig

ital W

ater

mar

king

Te

chno

logy

for I

P Pr

otec

tion

2.R

evie

w o

f IP

Prot

ectio

n Te

chno

logi

es fo

r AS

IC a

nd F

PGA

Des

ign

3.R

evie

w o

f Wat

erm

arki

ng S

chem

es fo

r Fi

lter D

esig

n 4.

Prop

osed

New

Wat

erm

arki

ng M

etho

ds fo

r FP

GA

Impl

emen

tatio

n of

FIR

Filt

er

3

1. In

trod

uctio

n

�W

hat i

s th

e si

gnifi

canc

e of

IP p

rote

ctio

n?�

Wha

t is

a di

gita

l wat

erm

ark?

�W

hat i

s w

ater

mar

king

tech

nolo

gy?

�H

ow a

dig

ital w

ater

mar

k is

em

bedd

ed a

nd

dete

cted

?

4

1.1.

Sign

ifica

nce

of IP

Pro

tect

ion

�C

opyr

ight

pro

tect

ion

is n

eede

d fo

r va

rious

di

gita

l pro

duct

s�

Dig

ital s

till i

mag

es�

Dig

ital a

udio

pro

duct

s (i.

e., m

usic

CD

)�

Dig

ital v

ideo

pro

duct

s (i.

e., D

VD m

ovie

s)�

Softw

are

sour

ce c

ode

�AS

IC a

nd F

PGA

IP c

ores

�El

ectro

nic

publ

icat

ions

5

1.2.

Wha

t is

a Di

gita

l Wat

erm

ark

and

Wat

erm

arki

ng T

echn

olog

y?

�A

digi

tal

wat

erm

ark

is a

pie

ce o

f in

form

atio

n hi

dden

in

side

th

e IP

th

at

show

s IP

ow

ner�s

id

entit

y.

�W

ater

mar

king

re

fers

to

th

e te

chno

logy

to

em

bed

a di

gita

l wat

erm

ark

into

a d

igita

l IP

and

to

dete

ct it

from

a d

igita

l IP

with

wat

erm

ark.

6

Info

rmat

ion

Hid

ing

Cov

ert

Cha

nnel

sSt

egan

ogra

phy

Anon

ymity

Cop

yrig

ht m

arki

ng

Ling

ustic

st

egan

ogra

phy

Tech

nica

l st

egan

ogra

phy

Rob

ust

copy

right

mar

king

Frag

ile

wat

erm

arki

ng

Fing

erpr

intin

gW

ater

mar

king

Impe

rcep

tible

w

ater

mar

king

Visi

ble

wat

erm

arki

ng

Info

rmat

ion

Hid

ing

and

Wat

erm

arki

ng

7

�C

riter

ia fo

r a w

ater

mar

king

tech

nolo

gy�

Easy

to e

mbe

d an

d de

tect

a w

ater

mar

k�

Diff

icul

t to

rem

ove

the

wat

erm

ark

�Lo

w d

esig

n an

d im

plem

enta

tion

over

head

or c

ost

�W

ater

mar

king

tech

nolo

gy h

as a

pplic

atio

ns fo

r �

Cop

yrig

ht p

rote

ctio

n�

Fing

erpr

intin

g�

Dat

a au

then

ticat

ion

�D

ata

hidi

ng

8

1.3.

Wat

erm

ark

Embe

ddin

g an

d D

etec

tion:

Sche

me

for E

mbe

ddin

g a

Wat

erm

ark

Embe

ddin

gal

gorit

hm

Wat

erm

ark

Key

Orig

inal

dig

ital I

PM

arke

ddi

gita

l IP

9

Sche

me

for W

ater

mar

kD

etec

tion

Det

ectio

n al

gorit

hm

Mar

k an

d/or

orig

inal

dig

ital I

P

Key

Test

-dig

ital I

P

Wat

erm

ark

or

conf

iden

ce m

easu

re

10

2. IP

Pro

tect

ion

for A

SIC

and

FPG

A D

esig

ns

11

2.1.

Non

-wat

erm

arki

ng m

etho

ds fo

r

ASIC

and

FPG

A de

sign

IP p

rote

ctio

n:

�IP

ow

ners

try

to p

rote

ct th

eir c

opyr

ight

by

encr

yptin

gVH

DL/

Veril

og s

ourc

e co

des

befo

re

send

ing

them

to th

e us

ers.

�

The

encr

ypte

d co

des

are

load

ed in

to

auth

oriz

ed s

imul

ator

sor

syn

thes

is to

ols.

�Th

e so

urce

cod

es a

re in

visi

ble

to th

e sy

stem

de

sign

er w

ho u

ses

the

IP b

lock

s.

12

Non

-wat

erm

arki

ng m

etho

ds a

re n

otse

cure

en

ough

:�

The

CAD

to

olm

aint

ains

the

saf

ety

of t

he

copy

right

. �

In

prac

tice,

th

is

can

ofte

n be

bro

ken

by

atta

ckin

g th

e C

AD t

ool (

sim

ulat

ors,

syn

thes

is

tool

) dire

ctly

. �

Bette

r m

etho

ds a

re n

eede

d fo

r pr

otec

tion

of

the

ASIC

and

FPG

A IP

.

13

2.2.

Wat

erm

arki

ng m

etho

ds fo

r VLS

I/FPG

A

�Ad

vant

ages

of w

ater

mar

king

met

hods

�VL

SI/F

PGA

IP w

ater

mar

king

can

hel

p de

ter

thef

tand

cou

nter

feiti

ng.

�Th

e em

bedd

ed w

ater

mar

k se

rves

as

evid

ence

of

ow

ners

hip.

�A

wat

erm

arki

ng

met

hod

incl

udes

tw

o ph

ases

�W

ater

mar

k sy

nthe

sis

�W

ater

mar

k de

tect

ion

14

FPG

A an

d AS

IC W

ater

mar

king

Sch

emes

1.Fi

nger

prin

ting

for F

PGA

IP p

rote

ctio

n�

This

met

hod

uses

the

unus

ed L

UT

(look

-up

tabl

e) b

its to

em

bed

the

sign

atur

e bi

ts.

2.C

hang

e of

FPG

A bi

t-str

eam

dat

a�

The

met

hod

subs

titut

es w

ater

mar

k bi

ts f

or

som

e of

the

bits

in

the

conf

igur

atio

n bi

t-st

ream

th

at

cont

rols

m

ultip

lexe

rs

for

the

unus

ed C

LB o

utpu

ts.

15

3.

Hie

rarc

hica

l wat

erm

arki

ng�

It us

es a

n un

ique

map

ping

of

topo

logi

cal

info

rmat

ion

onto

a s

eque

nce

of s

ymbo

ls.

4.

Prot

ocol

s fo

r IP

prot

ectio

n�

Hid

e w

ater

mar

k da

ta a

t th

e co

mbi

natio

nal

logi

c sy

nthe

sis

leve

l.

5.

Fing

er-m

arki

ng�

Hid

e w

ater

mar

k at

th

e la

yout

le

vel

by

mod

ifyin

g th

e tra

nsis

tor W

/L a

nd th

e nu

mbe

r of

fing

ers.

16

3. R

evie

w o

f Filt

er D

esig

n W

ater

mar

king

�Th

ree

tech

nolo

gies

hav

e be

en p

ropo

sed:

�M

agni

tude

mod

ifica

tion

�Fi

lter t

ap�s

equ

al-re

plac

emen

t�

Win

dow

ing

func

tion

wat

erm

arki

ng

17

3.1.

Mag

nitu

de M

odifi

catio

n

�St

ep 1

: Pre

pare

wat

erm

ark

code

(i.e

., 7-

bits

)�

Step

2: S

epar

ate

the

filte

r sto

p or

pas

s-ba

nd

to s

ever

al e

qual

wid

th z

ones

(i.e

., se

ven

zo

nes)

�St

ep 3

: Mod

ify th

e fil

ter m

agni

tude

resp

onse

ac

cord

ing

to th

e w

ater

mar

k b

its:

�If

the

bit i

s 1,

decr

ease

the

filte

r mag

nitu

de

resp

onse

by

1 dB

.�

If th

e bi

t is

0,in

crea

seth

e fil

ter m

agni

tude

re

spon

se b

y 1

dB

.

18

3.1.

Mag

nitu

de M

odifi

catio

n (C

on�t)

�St

ep 4

: Use

the

mod

ified

filte

r mag

nitu

de re

spon

se a

s th

e de

sign

con

stra

ins

inpu

t to

the

desi

gn to

ol.

�St

ep 5

: Obt

ain

the

filte

r coe

ffici

ents

.

19

Mag

nitu

de re

spon

se o

f the

filte

r with

wat

erm

arki

ng

0-1-

1-0-

1-0-

1

20

Adva

ntag

es o

f thi

s m

etho

d:�

Add

wat

erm

ark

at a

lgor

ithm

leve

l, th

e hi

ghes

t lev

el

for f

ilter

des

ign

�H

ard

to re

mov

e fro

m lo

wer

leve

l of f

ilter

�s

impl

emen

tatio

n, li

ke lo

gic,

layo

ut o

r circ

uit l

evel

Dis

adva

ntag

es o

f thi

s m

etho

d:�

Incr

ease

the

com

plex

ityof

filte

r des

ign.

�In

crea

se th

e or

der o

f filt

er, s

ince

we

intro

duce

new

rip

ple

cons

train

to th

e fil

ter m

agni

tude

resp

onse

�In

crea

se th

e ha

rdw

are

cost

by +

7%

21

3.2.

Filte

r wat

erm

arki

ng b

y fil

ter t

ap�s

equ

al-

repl

acem

ent

�Pr

oced

ure:

�St

ep 1

: Pre

pare

the

wat

erm

ark

(7-b

its).

�St

ep 2

: Des

ign

the

filte

r with

the

orig

inal

pe

rform

ance

spe

cific

atio

n.�

Step

3: R

epla

ce th

e fil

ter t

aps

by u

sing

equ

al

filte

r stru

ctur

e re

plac

emen

t.�

Ther

e ar

e th

ree

equa

l fun

ctio

n fil

ter s

truct

ures

, A, B

and

C.

�W

hen

the

wat

erm

arki

ng b

it is

0,us

e B

to im

plem

ent

this

tap.

�W

hen

the

wat

erm

arki

ng b

it is

1,u

se C

to im

plem

ent

this

tap.

22

Equa

l-rep

lace

men

t filt

er w

ater

mar

king

Typ

e A

Typ

e B

Typ

e C

23

Adva

ntag

es o

f thi

s m

etho

d:�

Wat

erm

arki

ng a

t alg

orith

mle

vel,

hard

to re

mov

e at

the

low

er le

vels

�N

o de

grad

atio

n of

filte

r per

form

ance

Dis

adva

ntag

es o

f thi

s m

etho

d:�

Incr

ease

har

dwar

e co

st d

ram

atic

ally

by

+33%

�M

ake

the

filte

r stru

ctur

e no

t uni

form

, and

in

crea

se th

e de

sign

tim

e fo

r im

plem

enta

tion

w

ith A

SIC

or F

PGA

24

3.3.

Win

dow

ing

func

tion

wat

erm

arki

ng

�Pr

oced

ure:

�St

ep 1

:�

Supp

ose

W(n

) is

the

orig

inal

win

dow

func

tion,

w

here

1<=

n <

=N.

�Ad

d ra

ndom

noi

se to

W(n

) to

obta

in W

m(n

)W

m(n

)=W

(n)+

a * r

(n),1

<=n<

=N,

�Se

lect

a a

s 0.

001

�r(n

) is

a ra

ndom

seq

uenc

e w

ith z

ero

mea

n

25

�St

ep 2

: Wm

(n),

1<=

n <

= i-1

Wc(

n) =

W

m(n

)+b*

c(n-

i+1)

, i

<= n

<=i

+P-1

Wm

(n),

i+

P<=

n <=

N/2

Wc(

N+1

-n),

N

/2+1

<= n

<=N

.

�Se

lect

b=0

.000

1.�

The

star

ting

bit o

f the

P-b

it w

ater

mar

k co

de

sequ

ence

c(n

-i+1)

is b

it i o

f Wm

(n).

�Th

e se

quen

ce W

c(n)

, n=1

,�,N

, is

the

new

w

indo

w fu

nctio

n w

hich

con

tain

s th

e w

ater

mar

k in

form

atio

n.

26

�Ad

vant

ages

of t

his

met

hod:

�Em

bedd

ing

wat

erm

ark

at a

lgor

ithm

leve

l whi

ch is

ha

rd to

rem

ove

at a

low

er le

ver

�Si

mpl

e an

d di

rect

wat

erm

ark

embe

ddin

g sc

hem

e

�D

isad

vant

ages

of t

his

met

hod:

�In

crea

se d

esig

n co

mpl

exity

27

4. N

ew P

ropo

sals

for F

IR F

ilter

W

ater

mar

king

with

FPG

A Im

plem

enta

tion

�Pr

opos

al o

ne:

�Em

bedd

ing

wat

erm

ark

at F

IR fi

lter

coef

ficie

nts�

LSB

�Pr

opos

al tw

o:

�FP

GA

RAM

cel

l loc

atio

ns� w

ater

mar

king

28

4.1.

Prop

osal

One

: FI

R F

ilter

Coe

ffici

ents

� LSB

Wat

erm

arki

ng

�Le

t a F

IR fi

lter d

esig

n be

giv

en b

y

Y(k)

=A0*

x(k)

+A1*

x(k-

1)+�

�+A

n-1*

x(k-

N-1

),w

here

k=0

,1,�

�,N

-1.

A0,A

1,�

�An

-1 a

re fi

lter c

oeffi

cien

ts.

�A

wat

erm

ark,

for i

nsta

nce,

is g

iven

by

1000

1010

�W

ater

mar

k em

bedd

ing

proc

ess

is to

repl

ace

the

filte

r coe

ffici

ents

� LSB

s w

ith th

e w

ater

mar

k bi

ts.

29

011

11-1

110-

0101

-011

0A7

:111

1-11

10-0

101-

0110

100

00-0

001-

1111

-101

1A6

:000

0-00

01-1

111-

1010

000

00-1

000-

1101

-111

0A5

:000

0-10

00-1

101-

1111

100

00-0

011-

0111

-100

1A4

:000

0-00

11-0

111-

1000

000

00-0

000-

1110

-101

0A3

:000

0-00

00-1

110-

1010

011

11-1

111-

1010

-100

0A2

:111

1-11

11-1

010-

1001

011

11-1

111-

0100

-110

0A1

:111

1-11

11-0

100-

1101

111

11-1

111-

1100

-010

1A0

:111

1-11

11-1

100-

0100

Wat

erm

ark

bits

Mod

ified

Filt

er

Coe

ffici

ents

Orig

inal

Filt

er C

oeffi

cien

ts

30

Mag

nitu

de re

spon

se s

imul

atio

n re

sults

:FI

R fi

lter c

oeffi

cien

ts� L

SB w

ater

mar

king

(left:

bef

ore

wat

erm

arki

ng

right

: afte

r wat

erm

arki

ng)

00.

10.

20.

30.

40.

50.

60.

70.

80.

91

-90

-80

-70

-60

-50

-40

-30

-20

-10010

Norm

alize

d Fr

eque

ncy

( ×π r

ad/s

ample

)

Magnitude (dB)

Magn

itude

Res

pons

e

00.

10.

20.

30.

40.5

0.6

0.7

0.80.

91

-90

-80

-70

-60

-50

-40

-30

-20

-10010

Norm

alize

d Fre

quen

cy (×π

rad/

samp

le)

Magnitude (dB)

Magn

itude

Res

pons

e

Nor

maliz

ed Fr

eque

ncy:

0.0

0391

M

agnit

ude

(dB)

: 4.5

1

Nor

maliz

ed F

requ

ency

: 0.58

8 M

agnit

ude (

dB):

-29.

4 N

orma

lized

Freq

uenc

y: 0.

781

Mag

nitud

e (dB

): -2

9.3

31

4.2.

Prop

osal

Tw

o:

FPG

A R

AM C

ell L

ocat

ions

� Wat

erm

arki

ng

�Le

t a F

IR fi

lter d

esig

n be

giv

en b

yY(

k)=A

0*X(

k)+A

1*X(

k-1)

+��

+An-

1*X(

k-N

-1),

whe

re k

=0,1

,�.N

-1.

�Su

ppos

e a

wat

erm

ark

cons

ists

of 8

bits

as

10

0010

10.

�Le

t the

RAM

cel

l to

stor

e A

i be

RAM

_i,

i=0,

1,�

,7.

�A

RAM

cel

l on

FPG

A ci

rcui

ts c

an b

e id

entif

ied

by it

s co

ordi

nate

s (a

, b).

�W

ater

mar

k bi

ts e

mbe

ddin

g ru

le:

�If

the

bits

are

00,

we

choo

se b

oth

a an

d b

as e

ven.

�If

the

bits

are

01,

we

choo

se a

as

even

and

b as

odd

.�

If th

e bi

ts a

re 1

0, w

e ch

oose

a a

s od

dan

d b

as e

ven.

�If

the

bits

are

11,

we

choo

se b

oth

a an

d b

as o

dd.

32

(0,0

)(2

3,0)

(0,2

3)(2

3,23

)

33

0(3

,0)

1R

AM_3

0(3

,2)

1R

AM_2

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catio

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bits

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34

FIR

filte

r pla

ce a

nd ro

ute

resu

lts:

left:

befo

re w

ater

mar

king

right

:afte

r wat

erm

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ng

489/

1536

106.

474

MHz

Afte

r wat

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488/

1536

107.

654

MHz

Befo

re w

ater

mar

king

Har

dwar

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requ

ency

35

Adva

ntag

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visi

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ial

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cker

.�

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bot

h al

gorit

hm a

nd

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ut le

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crea

sing

sec

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ngth

and

the

time

for

reve

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neer

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Dis

adva

ntag

es o

f the

pro

pose

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r the

firs

t pro

pose

d m

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perfo

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light

ly w

orse

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the

mod

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lter c

oeffi

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r the

sec

ond

prop

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, max

freq

uenc

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usag

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ly w

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al d

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36

Com

pari

son

of P

ropo

sal O

ne w

ith C

urre

nt M

etho

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t alg

orith

m le

vel)

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nitu

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Mod

ifica

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Tap

's

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al

Rep

lace

men

tW

indo

win

g Fu

nctio

n W

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mar

king

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osal

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(FIR

Fi

lter

LSB

W

ater

mar

king

)

Filte

r Pe

rfor

man

ce

Deg

rada

tion

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ium

Smal

lSm

all

Smal

l

Har

dwar

e U

sage

Incr

ease

+7%

+29%

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0%

Des

ign

Ove

rhea

dH

igh

Med

ium

Low

Low

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ract

ion

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owM

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mL

owM

ediu

m

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abili

ty

of

Coi

ncid

ence

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Low

Low

Low

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rity

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ium

Med

ium

Low

Med

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37

Usi

ng

Spar

e LU

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ty

of

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ncid

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Low

Low

Low

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Low

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h

App

lied

Are

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GA

FP

GA

ASI

C

(dig

ital)

ASI

C

(d

igita

l)A

SIC

(m

ix-

sign

al)

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A

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pari

son

of P

ropo

sal T

wo

with

Cur

rent

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hods

(at p

hysi

cal/R

TL

des

ign

leve

l)

38

�Th

anks

for y

our t

ime

!

�An

y qu

estio

ns &

adv

ice?