1. Front-end computations in human vision Jitendra Malik U.C. Berkeley References: DeValois & DeValois,Hubel, Palmer, Spillman &Werner, Wandell Jitendra Malik U.C. Berkeley References: DeValois & DeValois,Hubel, Palmer, Spillman &Werner, Wandell

3. Cerebral Cortex

7. Monocular Visual Field: 160 deg (w) X 135 deg (h) Binocular Visual Field: 200 deg (w) X 135 deg (h)

10. Cones and Rods

16. ON and OFF cells in retinal ganglia

20. Modeling simple cells Elongated directional Gaussian derivatives 2nd derivative and Hilbert transform L 1 normalized for scale invariance 6 orientations, 3 scales Zero mean Elongated directional Gaussian derivatives 2nd derivative and Hilbert transform L 1 normalized for scale invariance 6 orientations, 3 scales Zero mean

22. Orientation Energy Gaussian 2nd derivative and its Hilbert pair Can detect combination of bar and edge features; also insensitive to linear shading [Perona&Malik 90] Multiple scales

26. Visual Processing Areas

27. Macaque Visual Areas

30. Textons (Malik et al, IJCV 2001) K-means on vectors of filter responses

31. Textons (cont.)

32. Texton Histograms i j k Chi square test: 0.1 0.8

33. CSF as function of eccentricity

34. Receptor density vs eccentricity

35. Cortical Magnification Factor

36. Mapping from Retina to V1