| 00:00:00 | Welcome |
| 00:01:41 | The math(ematics) of image analysis |
| 00:01:53 | Abstract |
| 00:02:45 | Agenda |
| 00:03:12 | Most important questions – the big picture |
| 00:05:14 | O2Q |
| 00:06:00 | The ‘smaller’ picture |
| 00:07:32 | Basic principles of image analysis |
| 00:08:15 | Before the analysis – taking the sample |
| 00:09:12 | Taking a (hopefully representative?) sampleHopelessly unrepresentative? |
| 00:11:49 | The sample |
| 00:12:28 | Image Analysis – basics and expanded from CarltonFull reference later |
| 00:12:56 | Image acquisition – the key part |
| 00:14:40 | Eric Pirard Personal communication October 5th, 2010: 06:21 AM |
| 00:15:37 | Resolution - Definition |
| 00:16:15 | Lower limit - diffraction |
| 00:16:48 | Numerical Aperture (N.A.) |
| 00:17:02 | Limits of resolution |
| 00:17:54 | Limits of resolution |
| 00:18:39 | Untitled |
| 00:19:15 | Heywood’s warning |
| 00:20:16 | Defeating the Abbe limit |
| 00:20:41 | Nobel Prize in Chemistry - 2014 |
| 00:21:06 | Possibilities and Limitations |
| 00:21:43 | Magnification |
| 00:22:24 | Depth of field |
| 00:23:02 | Depth of field |
| 00:23:35 | Depth of field |
| 00:24:01 | Focus |
| 00:24:59 | Object extraction |
| 00:25:35 | Image J – simple example |
| 00:26:05 | Isolation of image from background – 256 levels |
| 00:26:35 | Noise removal |
| 00:27:27 | Binarization |
| 00:28:08 | Variable background – Image J |
| 00:28:41 | Variable background |
| 00:29:25 | Digitization – care! From ISO 9276-6Pixel resolution and 16:9 display… |
| 00:30:33 | Particle orientation with respect to x- and y-axes |
| 00:31:46 | Edge and perimeter isolation: 8-neighbor |
| 00:32:10 | Thresholding |
| 00:33:18 | Object Extraction - Thresholding |
| 00:34:15 | Thresholding |
| 00:34:46 | Erosion-dilation |
| 00:35:47 | Hole filling |
| 00:36:44 | How do we count the number of particles? |
| 00:37:35 | De-agglomeration – in software!Processing (Erosion-Dilation)Post-processing (Circularity) |
| 00:38:37 | Original image (10MB picture) |
| 00:39:08 | Decide which part of the image to analyze |
| 00:39:44 | Extract the sample |
| 00:40:00 | Process 1 – negative imageGrey scale (256 levels) |
| 00:40:16 | Digitize (2 colors) |
| 00:40:24 | Process 1 – negative imageGrey scale (256 levels) |
| 00:40:28 | Digitize (2 colors) |
| 00:40:34 | The original and processed image overlaid |
| 00:41:12 | ImageJ – jpeg warning (page 57 of manual) |
| 00:41:42 | What have we lost? |
| 00:42:00 | The lost tree (increasing brightness and contrast) |
| 00:42:18 | Note these ‘particles’ – appear as an aggregateLet’s carefully examine the original 10 MB photograph |
| 00:43:02 | Threshold – automatic setting |
| 00:43:30 | Threshold |
| 00:43:50 | Threshold |
| 00:44:15 | Process the data (1269 particles) – automatic threshold: using 1 mm/pixel for convenience |
| 00:44:45 | Lots of data per particle Size and shape on the same plot |
| 00:45:09 | Threshold 25 (359 particles) |
| 00:45:50 | Compare threshold results for 1269 and 359 particles Number distribution |
| 00:46:07 | Shape information – aspect ratio - distribution |
| 00:46:36 | Circularity - distribution |
| 00:46:46 | The Tetris effect – take care when you’re at the lower limit (low numbers of pixels/small particles) |
| 00:47:46 | So what does that give us? |
| 00:47:55 | So, we have binary, digitized images of particlesPost-processing – generation of shape parameters |
| 00:48:29 | 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 |
| 00:48:51 | A couple of common parameters |
| 00:49:29 | Area-volume |
| 00:49:45 | Post processing – the results – 2-D descriptorsAdditional complexity – and distributions…. |
| 00:50:07 | International Standards – documentaryWhere are the materials standards? |
| 00:50:18 | ISO9276-6 |
| 00:50:22 | ISO9276-6 |
| 00:50:54 | ASTM F1877 - 05(2010) |
| 00:51:20 | We’ll end with Heywood’s warning |
| 00:51:40 | References |
| 00:52:20 | References |
| 00:52:42 | Past (relevant?) webinars |
| 00:53:29 | Thank you! |
| 00:54:19 | Thank you for your attentionAny questions? |
| 01:03:04 | Contact Information |
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.