In connection with a business project, I need to find the real distance between two points in the images received from the mobile phone. Due to the lack of information such as the physical size of image sensors in smartphone cameras in the EXIF file, by estimating the distance and forcing the user to place an object with a certain height and width in the image, I was able to estimate the size of the image sensor but with some error. But these errors can be avoided and will not be very problematic. To do this, I followed the tips in this post.
Now I am looking to find the distance between two points in the image. According to this link,
calculate the real distance between to point using image
the distance between the two desired points can be obtained, but I did not understand how the column and row in this formula are obtained.
I would be very grateful if I could get help. If I went the wrong way, thank you for explaining
In the link you shared, the points u,v are image centers, which are found using the sensor/digitizer row and column and the width and height of the image.
This paper explains image centers well: https://www.ri.cmu.edu/pub_files/pub4/willson_reg_1994_3/willson_reg_1994_3.pdf
But nonetheless, the row and column values are part of the actual camera itself, not relative to the image necessarily.
Beyond that point, everything else is found using those two values along with the z-axis value and focal length, which is then plugged into the Euclidian distance formula.