perm filename PSY.3A[DOC,TOB] blob
sn#106576 filedate 1974-06-13 generic text, type T, neo UTF8
00100 A Edges and Regions
00200 B Texture Edges
00300 C Depth Perception
00350 D Selective Attention
00375 High resolutio fovea-zoom
00380 eye tracking
00385 little used in AI- common idea
00390 hypothesis-verification (Shirai)
00400
00500 A Edges and regions
00600 non-equiv of intensity features to semantic features
00700 inadequacy of current techniques
00800
00900 A.1 local edge operator
01000 A.2 local edge organization
01100 A.3 more global edge organization
01105
01110 A.1 local edge operator
01115 design criteria-optimality
01120 duality region-boundary
01125
01130 sensitivity vs (cost,resolution,utility)
01135 insensitive to smooth gradients-later inhibition,Retinex
01140 2D not 1D-indistinguishable from noise except by extension
01145 range of sizes, for texture,pt features
01150 comp cost-optimality
01155 sensitivity-optimality
01160
01165 comp cost in terms of N pt support N=nxn
01170 lower bound in cost is k*N arith operations, where k≥2 to
01175 get several moments to find directionality
01180 example k=2, N=8x8 implies 128 arith operations per application
01185 include the effect of applying every bth pixel
01190 allows directly nxn parellelism
01195
01200 sensitivity
01205 contrast required for 50% false negatives at an edge
01210 for 5% false positives at no edge
01215 signal=(N/2)*h
01220 noise=sqrt(N)*sigma
01225 cutoff threshold: signal = 2* noise
01230 (N/2)*h=2*sqrt(N)*sigma
01235 contrast h = 4*sigma/sqrt(N)
01240 account for a variety of directions by including a factor of sqrt(2)
01245 for vertical and horizontal directions.
01250 Thus the optimal is approximately h = 4*sqrt(2)*sigma/sqrt(N)
01255 or for a 6x6 support, h ≥ .9*sigma
01260 The Hueckel operator gives h = 1.4*sigma
01265 Thus, the Hueckel operator is not terribly far from optimal,
01270 and not much is to be gained by improvements in sensitivity.
01370
01470
01570 computation cost for Hueckel operator
01670 52 pt disk, 3mult, 9add per point +300 operations solution
01770 150 mult + 450 add +300 operations,,, about 10 msec
01870 32 pt disk, 3mult, 9add per point +300 operations solution
01970 100 mult 280 add, +300 operations,,, about 7 msec/application
02070
02170 edge organization
02270 breakdown into local thresholding and global to lower comp cost
02370 as disk larger, more and more possibilities for lines and curves
02470 more and more specks implies necessity of non-linear techniques
02570 optimal curve schemes
02670 use neat enumeration
02770 predictions of shape of curve
02870 continuity
02970 heuristic search
03070 vertices and local continuity operations
03170
03270
03370 using sub-threshold values
03470 global projection organization techniques
03570 strict continuity w/o smoothness, region techniques
03670 continuity w/ smoothness
03770 proximity
03870 non-linear evaluation functions
03970 how to use computation power