0

Normally when i google to convert pixel to mm,it's saying

1pixel = 0.264 mm

Is this value is same for every resolution value, if I need this conversion in 512*512 resolution.How can I do it?

temp
  • 265
  • 1
  • 4
  • 12
  • This question does not fit on StackOverflow since it is not related to an issue with code. Therefore, I am voting to close. – CConard96 Sep 11 '16 at 12:26
  • Also, you might want to research a little bit more before asking a question: http://stackoverflow.com/a/16275262/4195825 – px06 Sep 11 '16 at 12:27
  • Sorry for the wrong question,i though it was related to image processing and i can ask.sorry – temp Sep 11 '16 at 12:28
  • The size and shape of a pixel depends on the display device, if your display with 512 pixels is 51.2 mm wide a pixel will be 0.1 mm wide – Joni Sep 11 '16 at 12:53
  • @Joni I need to calculate the size of my image,so before calculating the size,i changed the resolution of image to 512*512 resolution.I didn't understand you comment. Can you please elaborate it – temp Sep 11 '16 at 13:00
  • @CConard96 you could at least point him wo somewhere he would find help... If you can't help someone, at least show him the way – Piglet Sep 11 '16 at 13:57

1 Answers1

1

Please read something on the basics of image processing. Then you can answer the question for yourself and you will have a chance to actually do some image processing without coming here ever 5 minutes.

A pixel does not have a size per se. Only if you determin the pixel size for some perticular scenario you can translate between pixels and meters.

Please also note that display elements and sensor elements are also often called pixels. Display and sensor elements do have a physical size.

Read: https://en.wikipedia.org/wiki/Digital_camera https://en.wikipedia.org/wiki/Dots_per_inch https://en.wikipedia.org/wiki/Resolution_independence https://en.wikipedia.org/wiki/Display_resolution https://en.wikipedia.org/wiki/Image_resolution https://en.wikipedia.org/wiki/Pinhole_camera_model

and anything else you need to understand what a pixel is.

In general if you want to display something in a given size you have to know how big one pixel is displayed. Then simply divide the wanted size by that pixel size to get the number of pixels you have to display. If you want to get the metric size of an object in your image take the number of pixels and multiply that with the pixel size.

Pixel sizes have to be calibrated or taken from image sensor or display datasheets. You cannot simply google for a universal translation factor.

Piglet
  • 27,501
  • 3
  • 20
  • 43