texture synthesis by non-parametric sampling viva-vital nazia tabassum 27 july 2015

TEXTURE SYNTHESIS BY NON-PARAMETRIC

SAMPLING

VIVA-VITALNazia Tabassum27 July 2015

WHY SYNTHESIZE TEXTURE?

INSPIRATION – MARKOV CHAIN

HOW TEXTURE SYNTHESIS WORKS

In the black region, select neighborhood of size w

Calculate “distance” between this patch and all patches in sample texture

Find best match Construct conditional probability

distribution including best match and other well matched neighborhoods

Less than a minimum distance (function of best match

Can give equal weights, OR better matches have higher probability

Randomly sample from this distribution

Use center pixel of neighborhood chosen as new pixel value

w

EFFECT OF WINDOW SIZE

Window Width:

5 11 15 23

EFFECT OF WINDOW SIZE

FAILURE EXAMPLE

Produces garbage because not enough good matches

Duplicate texture because one “best” match keeps getting picked

Again, not enough good matches

No matches found that are below minimum distance threshold

Can be solved by providing larger sample texture

IMPERFECT TEXTURE SYNTHESIS

IMPROVEMENT OVER EARLIER APPROACH

THANK YOU! QUESTIONS?