Fundamentals acquisition processing to an image models blob

Fundamentals • acquisition • processing to an image • models • blob coloring algoritm 2007 Theo Schouten

Acquisition and processing 2007 Theo Schouten

CCD chips 2007 Theo Schouten

CT scan 2007 Theo Schouten

MRI scan • strong magnetic field 1, 5 Tesla, alignment of spin of bounded protons, 13 C and 31 P • electromagnetic pulse, disruption • spin-lattice or T 1, and spin-spin or T 2 relaxation: EM radiation • 3 D image after large number of measurements 2007 Theo Schouten

Ultrasound • doppler effect: speed of blood • much technical improvements • also 3 D images 2007 Theo Schouten

Structured light 2007 Theo Schouten

Spot ranger 2007 Theo Schouten

CCD focus The active method uses an infrared bundle. The amount of received reflected light is proportional to the distance to the object. With the aid of a motor, the lens is the placed in the appropriate position. 2007 Theo Schouten passive method: lens is moved until (the center of) the acquired image is as sharp as possible. The average difference between the pixels and their neighboring pixels is used to determine the how sharp the image is.

Image functions f(x) = f(x, y) the light intensity or energy on position x f(x) = i(x). r(x) f(x) = { fred(x), fgreen(x), fblue(x)} digitizing models aspect ratio’s: 1, 4/3 16/9 quantization models: number of bits for light per pixel per color 1: binary image 8: gray or color images trend to higher numbers: 10, 12, 16 2007 Theo Schouten

Geometric models |u| |a 11 |v| = |a 21 |w| |a 31 |a 41 2007 a 12 a 22 a 42 a 23 a 33 a 43 a 14| a 24| a 34| a 44| |X| |Y| |Z| |1| and x = u/w , y=v/w Theo Schouten

Stereo model 2007 Theo Schouten

Radiometric models Energy flux watts Radiant intensity I= d /d watts/steradian Solid angle (ruimte hoek) d =d. A/r 2 = d. Acos /r 2 Irradiance (instraling) E=d /d. A watts/m 2 Radiance (uitstraling) L=d 2 /d. Acos d Flux op lens van gebiedje A 0 : L d. Aod = L Ao cos met = /4 D 2 cos / (fo/ cos )2 Instraling op Ap : E= / Ap =L A 0 cos / Ap Centrum van lens ziet Ap en Ao onder dezelfde ruimte hoek: Ao cos /(fo/ cos )2 = Ap cos / (fp/ cos )2 Alles in E invullen: E= /4 (D/fp)2 L cos 4 2007 Theo Schouten

Eye color model 2007 Theo Schouten

RGB model CMY (K) 2007 Theo Schouten

Other color models 2007 Theo Schouten

Relations, blob coloring f(xu) f(xl) do: 1 0 color(xc) : = color(xu) 0 1 color(xc) : = color(xl) 0 0 color(xc) : = k ; k : = k+1 1 1 color(xc) : = color(xu) or color(xl) and store in a list: color(xu) == color(xl) 2007 Theo Schouten

Convolution operation • window (3 x 3) • mask or filter (values of w’s) • convolution: parallel operation • serial operation • for many methods both parallel and serial versions are known 2007 Theo Schouten