convert pixel to centimeters

[Brenny]

Hello, I want to convert pixel values to centimeters values. For example
start point is 100,100 pixel and stop point is 200,100 pixel.
distance is what cm?

How can I calculate distance as centimeters?

 

[Adman]

This would depend completely on the size of your physical display,
wouldn't it?

If you have a 12.8 centimeter display showing a 1280x1024 image, then
you have 100 pixels per centimeter.

Right?

 

[Bruce Wood]

You might look at the following articles on MSDN:

http://support.microsoft.com/default.aspx?scid=kb;en-us;127152

If you're not as picky as the above article, you can always use the
DpiX and DpiY properties of the Graphics object on which you're
drawing. (You must always determine pixels to inches based on some
output device... the conversion is meaningless in the absence of a
graphics context of some kind.) In DpiX and DpiY, the "D" stands for
"dots" or pixels, while the "i" stands for "inches". So, you can
convert pixels to inches. Then all you have to do is convert inches to
centimeters.

 

[Bruce Wood]

You may also find the Graphics.TransformPoints method useful.