i have a thresholded image and i need to find the real area of the black region

[prasse]

Hi klemen 

sorry for the inconvenience.your idea about pixel calibration was very useful that i have an idea of what u said to do it in a separate project .

but i think its not camera image. its a scanned image from flat bed scanner.

is there any means by which i do this option "set scale value" option so that we can get the value in mm square(area)

thanks a lot

regards 

🙂

[Klemen · Accepted solution]

Hello,

then you just need to find a scale factor that converts the pixels in mm. Scan an object (square for example) of known size and calculate the real area mm and the image area in pixels. Then divide the real area with the pixel area to get a scale constant with
mm^2/pix units. Then for every image area you calculate form histogram, multiply by this constant.

Maybe you should also use different size known objects to see if the relationship is linear. If it is not, you can model it differently.

Best regards,

K

[prasse]

Hi

this worked for me.after performing the histogram,i got the scale value in mm/pix which i used to find the real area by multiplying it with pix values..

thank you

prasse:)

[Klemen]

Hello,

i am glad you figured it out!

Best wishes on your future endeavours!

Best regards,

K