This document discusses various computer animation techniques. It begins with an introduction to animation and the concept of frame rate. There are three main types of animation discussed: traditional/hand-drawn animation where drawings are traced onto sheets for each frame; stop-motion animation which manipulates real-world objects; and computer animation which can be 2D or 3D. The document then covers animation sequences and key steps like storyboarding, object definition, key frames, and generating in-between frames. Specific computer animation techniques like raster animation and morphing are also summarized. The document concludes with applications of computer animation such as movies, video games, simulation, and more.

1. Welcome 1 Mahith

2. Computer Animation & Techniques 2 Mahith Seminar by Mahith Mohan

4. Name derived from “Anime” means life.It’s just an optical illusion of motion due to persistence of vision 3 Mahith

5. Simple Example A ball bouncing from just 6 frames 4 Mahith

7. NTSC TV 30 fps (interlaced)

8. PAL TV 25 fps (interlaced)

9. HDTV 60 fps

10. Computer ~60 fps5 Mahith

11. Classification of animation techniques 6 Mahith

13. Pictures are drawn for each frames.

14. The animators' drawings are traced or photocopied onto transparent acetate sheets called cels( celluloid transparency)

15. The completed character cels are photographed one-by-one onto motion picture film against a painted background by a rostrum camera.7 Mahith

16. Example 8 Mahith

17. Walt Disney Walt Disney, an American cartoonist and film producer, started an entertainment empire with his creation of animated movies and world-renowned amusement parks. Disney appears here at his drawing board in 1950 with a drawing of Mickey Mouse, his most famous cartoon character. Disney won an honorary Oscar (Academy Award) in 1932 for his creation of Mickey. . 9 Mahith

18. Stop Motion Animation Stop-motion animation is used to describe animation created by physically manipulating real-world objects and photographing them one frame of film at a time to create the illusion of movement. 10 Mahith

19. Example 11 Mahith

21. Mainly 2 types-

22. 2D animation

23. 3D animation12 Mahith

25. Consist set of rough sketches13 Mahith

27. Associated movement of each object are specified with the shape.14 Mahith

30. Determined by the media to be used to display. 16 Mahith

31. 1’ 1 2’ 2 Key frame k Key frame k+1 In-between frame 17 Mahith

33. It involves creating an image, and then using a computer to put that image in motion

34. Raster based animation frames are made up of individual pixels. These pixels each contain information about the colour and brightness of that particular spot on the image18 Mahith

35. Ship is redrawn in background color Step 2 (move) Step 1 (erase) Step 3 (draw) (x,y) (x+ Dx , , y+ Dy) (x’,y’) (x,y) x’ = x + Dx y’ = y + Dy Move ship Example: 19 Mahith

36. 20 Mahith

38. Here we set the successive blocks of pixel value to colour table. Object as “on” rest as background color.

39. Later successively positions along the path is changed to “on” and older position to background color.21 Mahith

41. Each object is formed with set of rigid bodies connected by several joints with limited degree of freedom.22 Mahith

43. Motion limitation

44. Allowable shape changes …. 23 Mahith

45. Computer Animation languages Scripting System: Object specifications & animation sequences are defined with a user-input script 24 Mahith

46. Morphing Transformation of object shape from one form to another is called Morphing ( Metamorphosis) 25 Mahith

47. Key frame Key frame In-between frame Three frames form a morph from George W. Bush to Arnold Schwarzenegger showing the mid-point between the two extremes 26 Mahith

48. 1’ 1 4’ 4 added point 2’ 2 Key frame k Key frame k+1 Halfway frame Linear interpolation for transforming triangle into a quadrilateral 3 3’ 27 Mahith

49. General preprocessing rules for Equalizing key frames Using edge count: Let Lk & L k+1 no of line segment in 2 consecutive key frame. Then Lmax =max(Lk ,Lk+1 ) , Lmin =min(Lk , Lk+1 ) And Ne = Lmax mod Lmin Ns = int(Lmax / Lmin ) Then the preprocessing is accomplished by Dividing Ne edges of keyframemin into Ns +1 sections Dividing the remaining lines of keyframemin into Ns sections. 28 Mahith

50. Key frame k+1 1’ Key frame k 1 4’ 2’ 2 General preprocessing rules for Equalizing key frames Example for by using edge count: 3 3’ L k =3 L k+1 =4 L max =4 , L min =3, N e = 1 , Ns =1 Divide 1 (N e ) edges of keyframe k (keyframe min ) to 2 (N s+1 ) section Since Ns =1 leave the remaining sections. 29 Mahith

51. General preprocessing rules for Equalizing key frames Using vertex count: Let Vk& Vk+1 no of vertex in 2 consecutive key frame. Then Vmax =max(Vk,Vk+1 ) , Vmin =min(Vk, Vk+1 ) And Nis = (Vmax -1) mod( Vmin -1) Np = int((Vmax-1) / (Vmin -1) Then the preprocessing is accomplished by adding Np points to Nis line section of key framemin. Adding Np -1 points to the remaining edges of key framemin 30 Mahith

52. Key frame k+1 1’ Key frame k 1 4’ 2’ 2 General preprocessing rules for Equalizing key frames Example for by using vertex count: 3 3’ V k =3 V k+1 =4 V max =4 , V min =3, N is = 1 , Np =1 Add 1 (N p ) point to 1 (N is ) line of keyframe k (keyframe min ) Since Np -1 =0 leave the remaining edges 31 Mahith

54. Non linear path is taken at the in-between frames.

55. To stimulate acceleration we adjust the time spacing for the in-betweens32 Mahith

56. For constant speed we use equal interval of time spacing. Let consider key frames at times t1 and t2 and having n in-between frames between these. then dt= (t2 – t1)/ n+1 And time for any in-between as: tBj = t1 +j* dt For accelerating we can use functions like 1-cosq, 0<q<p/2 Then time for any in-between is: tBj = t1 +dt ( 1-cos(jp/2(n+1) ) 33 Mahith

58. Then transformation matrices are applied to transform coordinate positions .

59. Or we can use approximate equation to specify some motion.34 Mahith

60. Path of a bouncing ball 35 Mahith

61. y(x) = A sin(wx+ q0 ) e-kx where A =initial amplitude w = angular frequency q0 = phase angle k= damping constant This show the path of a bouncing ball acquired from damped sine function 36 Mahith

63. At the opposite extremes we specify the motions in general terms which describes the action.

64. Later input directives will interpret in terms of component motion.37 Mahith

66. Also factors in maintaining balance, joint angle limitations, and collisions between the body and limbs.

67. And all this will be mentioned in kinematic description of the respective points.

68. It’s alternate approach is inverse kinematics.38 Mahith

70. Rest motion parameters are computed by the system.Disadvantage: There is no general analytical solution. Must be solved through non-linear programming techniques. 39 Mahith

72. Referred as Physically based system.

73. Motion is obtained from the force equations like Newton’s Law etc.

74. It give realistic effects in motion.

75. So it is used in case of complex rigid body system and some non rigid bodies like cloth etc40 Mahith

77. Computer software records positions, angles, velocities, accelerations, and impulses for all sensors

78. Typically captures sub-millimeter positions41 Mahith

80. Faster than manually creating animations

81. Can have much more natural looking motions and catch all movements of the object.

82. Disadvantages:

83. Can’t do anatomically impossible motions

84. Motion is restricted to the laws of physics.

85. Sensors attached to the skin can shift out of position during human movement causing real performance to differ from data recorded.42 Mahith

87. Video Games

88. Virtual Reality

89. Simulation, Training, Military

90. Medical

91. Robotics

92. Visualization

93. Communication43 Mahith

94. 44 Mahith Visit : www.mahissworld.co.cc