Re: Totally new here. Color Counter question
Posted by Robert Smith on Oct 11, 2019; 12:41am
URL: http://imagej.273.s1.nabble.com/Totally-new-here-Color-Counter-question-tp5022515p5022524.html
Hello Emily,
Herbie is very good, however I feel he may be a little off for what you wish to do.
I recommend you use the Process > Image Expression Parser(Macro). To use this you need to Image > Color > Split Channels (make sure to keep the original) then in the parser macro assign Red to A, Green to B, and Blue to C. Enter the equation in the field ,,,Sqrt(1-(A*A)/(B*B)) click OK. This will give you the B & W image in the attached. From there you can use any LUT you wish, then Histogram will give the percentage of the pixels at any of the colors used. This particluar LUT is the Physics(Inverted)
This is accomplished by determining the ratio of the Green and Red channels, which will vary as they develope. It is basically the same technique that N.A.S.A. uses to determine the health of vegetation.
Once you use it you can get a feel for if or when you may need to modify the equation. As the plant develops the green to red ratio will change which you can monitor as it does so.
Any further assistance need, just ask.
Bob
________________________________
From: Emily Teng <[hidden email]>
Sent: Wednesday, October 9, 2019 7:54 PM
To: [hidden email] <[hidden email]>
Subject: Totally new here. Color Counter question
Hello
I'm totally new to ImageJ and was hoping to get some guidance. I have
pictures of plants (jpg) that I need to analyze to get percent of
coloring. (Poinsettia plants. I'd like to get the percentage of either
red/pink/white of the plants as it develops). This is part of my
dissertation research. I have attached a sample image. It looks like the
Color Counter Plugin would be the best way to go from what I can tell? Is
this right?
If so, I don't understand what kind of processing I need to do to my
picture to get this to work. And after that, I must have to customize the
plugin so that it knows which colors I want it to count, correct? Since it
is not a clear red/pink, etc, I assume I would have to choose a range of
colors in the red range, or the pink range?
Is there documentation somewhere telling me how to do this? Or can someone
help me with this? I would really appreciate it.
Thank you so much for any help you can provide.
Emily
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URL: http://imagej.273.s1.nabble.com/Totally-new-here-Color-Counter-question-tp5022515p5022524.html
Hello Emily,
Herbie is very good, however I feel he may be a little off for what you wish to do.
I recommend you use the Process > Image Expression Parser(Macro). To use this you need to Image > Color > Split Channels (make sure to keep the original) then in the parser macro assign Red to A, Green to B, and Blue to C. Enter the equation in the field ,,,Sqrt(1-(A*A)/(B*B)) click OK. This will give you the B & W image in the attached. From there you can use any LUT you wish, then Histogram will give the percentage of the pixels at any of the colors used. This particluar LUT is the Physics(Inverted)
This is accomplished by determining the ratio of the Green and Red channels, which will vary as they develope. It is basically the same technique that N.A.S.A. uses to determine the health of vegetation.
Once you use it you can get a feel for if or when you may need to modify the equation. As the plant develops the green to red ratio will change which you can monitor as it does so.
Any further assistance need, just ask.
Bob
________________________________
From: Emily Teng <[hidden email]>
Sent: Wednesday, October 9, 2019 7:54 PM
To: [hidden email] <[hidden email]>
Subject: Totally new here. Color Counter question
Hello
I'm totally new to ImageJ and was hoping to get some guidance. I have
pictures of plants (jpg) that I need to analyze to get percent of
coloring. (Poinsettia plants. I'd like to get the percentage of either
red/pink/white of the plants as it develops). This is part of my
dissertation research. I have attached a sample image. It looks like the
Color Counter Plugin would be the best way to go from what I can tell? Is
this right?
If so, I don't understand what kind of processing I need to do to my
picture to get this to work. And after that, I must have to customize the
plugin so that it knows which colors I want it to count, correct? Since it
is not a clear red/pink, etc, I assume I would have to choose a range of
colors in the red range, or the pink range?
Is there documentation somewhere telling me how to do this? Or can someone
help me with this? I would really appreciate it.
Thank you so much for any help you can provide.
Emily
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ImageJ mailing list: https://eur02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fimagej.nih.gov%2Fij%2Flist.html&data=02%7C01%7C%7Ca750c05aac1742d7358708d74d15d6fd%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637062628562843860&sdata=Uv%2B4%2F14IJ2EAsWRJFCHT19dnEJDciy39V7BzP8lcDKk%3D&reserved=0
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