grain size analysis - imagej

ANALYZE PARTICLESBY USING IMAGEJhttp://rsb.info.nih.gov/ij/docs/menus/analyze.html#ap

By Nguyen Hoang Viet, PhD.

Content

Where to download

How to run ImageJ

Image Processing & Calculation

Visit this link:http://rsbweb.nih.gov/ij/download.html

Note: please check your window first, 32- or 64-bit system

Where to download

First – Run ImageJ program and Load the your image file.

How to run ImageJ

Open Image File

Run ImageJ: Start/All Programs/ImageJ/

Open Image File: File/Open…, choose the file and click OK

Image Processing & Calculation

Step 1 – Convert to 8-bit & Crop

Open Image File: File/Open…, choose the file and click OK - Grain Size Calculation.jpg

Convert to 8-bit: Image/Type/8-bit.

Crop: Draw a rectangular shape then Image/Type/Crop.

Save the cropped file: File/Save as/Jpeg… -Grain Size Calculation-Crop.tif

Measurement scale unit

Draw a rectangular shape fits on scale bar. You will see its width to be 237 px.

So, 1 m equals 79px.

Step 2: Convert to grainy image

Image/Adjust/Threshold:

Other processing:- Process/Binary/Erode- Process/Binary/Dilate

Step 3: Analyze Particles

Analyze/Analyze Particles …

There are two data files:

Results.xls

Summary.xls

Average grain size:

708 px2= 0,113 m2.

How to set new scale bar

Analyze/Set Scale

Then, the unit in imageJwill be µm (micrometer)

Step 4: Analyze data

Based on two data files in Excel format, you should find a software for doing further analysis. Such software like: Excel, MatLab, Origin, SciLab*, SciDAVis* …

*: free software

Step 4: Analyze data (2)

On the ‚Results‛ dialog. Choose Results/Distribution… the set bin number for ‘specify bins’ field: 10, 50 and 100.

Based on Histogram dialogClick on List to get data list,then you should use other software to draw the graph.

Histograms of the grain sizes

Grain sizes of cropped images

Acknowledgement

Thank my students, ATP k52 (Fall 2010), for doing well this homework and have good suggestion for further processing.

Any questions?

Please email me at viet4777@gmail.com for further information

Discussion time!