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Computer Graphics. Everything on computers that is not text or sound.Computer graphics as drawing pictures on computers.Nuclear Medicine uses computer graphics to display images. Graphic Software. General Programming Package (Graphic Library in C etc)Application Package (For None-programmer)Mode
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1. Topic 5 Concept of Computer Graphics Introduction
Output Primitives and Attributes
Two dimensional Viewing
Graphical User Interfaces
Three Dimensional Concepts
Three Dimensional Display in Nuclear Medicine
2. Computer Graphics Everything on computers that is not text or sound.
Computer graphics as drawing pictures on computers.
Nuclear Medicine uses computer graphics to display images
3. Graphic Software General Programming Package (Graphic Library in C etc)
Application Package (For None-programmer)
Modelling Transformation=>World Coordinates=>Normalised Coordinates
4. User Graphic Interface Consist of windows, pull-down and pop-up menus, icons, pointing device.
Popular graphic user interface: X windows, MS windows, Macintosh, OpenLook and Motif
Graphic package: Specialised interactive dialogue
General Graphic Package: interface to standard window system: PHIGS for X windows.
5. User Graphic Interface
6. Output Attributes
7. Transformation Pipeline
8. Display Processor in Graphic System
9. From Object Model to Display Device
10. Object Rendering
11. Basic Building Blocks For Pictures Output Primitives
Characters,
Geometric Entities.
Lines,
Filled Areas,
Colours
Polygons
12. Output Primitives -Lines and Points
13. Output Primitives - Circles
14. Output Primitives - Polygon
15. Properties of the Output Primitives
How it is displayed:
Intensity
Colour
Style
Pattern
16. Geometric Transformation
Change size, position or orientation:
translation
rotation
scaling
Altering or Manipulating Display
17. Transformations
18. Transformations
19. Two Dimensional Viewing Specify which part of the picture
which part of the picture
where to put the picture
Algorithms
Point Clipping
Line Clipping
Polygon Clipping
Text Clipping
20. Two Dimensional Viewing
21. 3D Object Representation Object Boundaries:
Plane,
Curved Surfaces
Object Interiors:
Solid Objects:
Boundary Representation
Space-partition Representation
22. 3D Object Representation
23. 3D Transformation Transformation
translation, rotation, scaling
Rotation in 3D
a composite of 3 rotations
X-axis rotation
24. 3D Transformation
25. 3D Display
View an object from any spatial position: front, top etc.
Projection onto a flat viewing surface.
26. 3D Display
27. Projection Specify a view plane
Projections
Parallel
Perspective
Projection transformation
Clipping
28. Parallel Projection
29. Perspective Projection
30. Different Viewing Directions
31. Changing of Reference Point
32. 3D Surface 3D Surface Detection:
Identify the visible surface
example: ray-casting method
Depth Cueing
the intensity of lines decreases from the front to the back of the object.
33. 3D Surface Detection
34. Depth Cueing
35. Types of Depth Cues Stereoscopic display (different image for different eye)
Hidden lines/surface removal
Depth weighting (less intensity for distant object)
Illumination (surface lighting)
Rotation (cine loops)
36. Surface Illumination Surface illumination:
the intensity of light that we should see.
Surface rendering algorithm
calculation of the light based on physical laws.
Radiosity algorithm: based on the propagation of radiant energy between the surface and the source.
37. Surface Illumination
38. Shading Techniques
39. Reflection and Transparency
40. Radiosity
41. Lighting Conditions
42. Colours in Computer Graphics
43. Colour Models Colour Model:
The method for explaining the properties or behaviour of colour within some particular context.
RGB Model:
based on tristimulus theory
44. Colour Models
45. Grey Scale
46. Logarithmic & Exponential
47. Colour Translation
48. Pseudo Colour Display
49. True Colour Display
50. 3D Display in Nuclear Medicine Slice-and-Dice Display
orthogonal slices, oblique slices
Ray Tracing Volume Rendering
- summed projection, maximum activity projection, volumeric compositing.
Surface Rendering
polygon tiling, binary voxel rendering.
Mapping
Bulls eye, cylindrical display
51. Slice-and-Dice
52. Ray Tracing
53. Surface Rendering
54. Volume Rendering
55. Bulls Eye Mapping
56. Clinical Applications in Nuclear Medicine Hot Spot Imaging
Volume rendering with maximum activity projection
Cardiac Imaging
Perfusion imaging(Bulls eye), surface rendering with colour.
Functional imaging (oxygen consumption), colouring blood-pool surface.
Gated Blood Pool Studies: cine display, surface rendering, maximum activity projection.
Brains.