Fecha registrada: November 19 2015

Duration: 01 hours 04 minutes 40 seconds

Thresholding, dilation, erosion, reporting - these are some of the terms used in image analysis. We'll explain some of the mathematics used in converting an image into size and shape information.
Table of contents
1. Welcome
01:41
2. The math(ematics) of image analysis
00:12
3. Abstract
00:52
4. Agenda
00:27
5. Most important questions – the big picture
02:02
6. O2Q
00:46
7. The ‘smaller’ picture
01:32
8. Basic principles of image analysis
00:43
9. Before the analysis – taking the sample
00:57
10. Taking a (hopefully representative?) sampleHopelessly unrepresentative?
02:37
11. The sample
00:39
12. Image Analysis – basics and expanded from CarltonFull reference later
00:28
13. Image acquisition – the key part
01:44
14. Eric Pirard Personal communication October 5th, 2010: 06:21 AM
00:57
15. Resolution - Definition
00:38
16. Lower limit - diffraction
00:33
17. Numerical Aperture (N.A.)
00:14
18. Limits of resolution
00:52
19. Limits of resolution
00:45
20. Untitled
00:36
21. Heywood’s warning
01:01
22. Defeating the Abbe limit
00:25
23. Nobel Prize in Chemistry - 2014
00:25
24. Possibilities and Limitations
00:37
25. Magnification
00:41
26. Depth of field
00:38
27. Depth of field
00:33
28. Depth of field
00:26
29. Focus
00:58
30. Object extraction
00:36
31. Image J – simple example
00:30
32. Isolation of image from background – 256 levels
00:30
33. Noise removal
00:52
34. Binarization
00:41
35. Variable background – Image J
00:33
36. Variable background
00:44
37. Digitization – care! From ISO 9276-6Pixel resolution and 16:9 display…
01:08
38. Particle orientation with respect to x- and y-axes
01:13
39. Edge and perimeter isolation: 8-neighbor
00:24
40. Thresholding
01:08
41. Object Extraction - Thresholding
00:57
42. Thresholding
00:31
43. Erosion-dilation
01:01
44. Hole filling
00:57
45. How do we count the number of particles?
00:51
46. De-agglomeration – in software!Processing (Erosion-Dilation)Post-processing (Circularity)
01:02
47. Original image (10MB picture)
00:31
48. Decide which part of the image to analyze
00:36
49. Extract the sample
00:16
50. Process 1 – negative imageGrey scale (256 levels)
00:16
51. Digitize (2 colors)
00:08
52. Process 1 – negative imageGrey scale (256 levels)
00:04
53. Digitize (2 colors)
00:06
54. The original and processed image overlaid
00:38
55. ImageJ – jpeg warning (page 57 of manual)
00:30
56. What have we lost?
00:18
57. The lost tree (increasing brightness and contrast)
00:18
58. Note these ‘particles’ – appear as an aggregateLet’s carefully examine the original 10 MB photograph
00:44
59. Threshold – automatic setting
00:28
60. Threshold
00:20
61. Threshold
00:25
62. Process the data (1269 particles) – automatic threshold: using 1 mm/pixel for convenience
00:30
63. Lots of data per particle Size and shape on the same plot
00:24
64. Threshold 25 (359 particles)
00:41
65. Compare threshold results for 1269 and 359 particles Number distribution
00:17
66. Shape information – aspect ratio - distribution
00:29
67. Circularity - distribution
00:10
68. The Tetris effect – take care when you’re at the lower limit (low numbers of pixels/small particles)
01:00
69. So what does that give us?
00:09
70. So, we have binary, digitized images of particlesPost-processing – generation of shape parameters
00:34
71. And this leads to these image analysis parameters….G Yamate, J D Stockham “Sizing particles using the microscope” Chapter 3 of J D Stockham, E G Fochtman (Eds.) Particle Size Analysis Ann Arbor Science Publishers Inc (1977) ISBN: 0 250 40189 4
00:22
72. A couple of common parameters
00:38
73. Area-volume
00:16
74. Post processing – the results – 2-D descriptorsAdditional complexity – and distributions….
00:22
75. International Standards – documentaryWhere are the materials standards?
00:11
76. ISO9276-6
00:04
77. ISO9276-6
00:32
78. ASTM F1877 - 05(2010)
00:26
79. We’ll end with Heywood’s warning
00:20
80. References
00:40
81. References
00:22
82. Past (relevant?) webinars
00:47
83. Thank you!
00:50
84. Thank you for your attentionAny questions?
08:45
85. Contact Information
01:36