Does anyone happen to know or find out any software/program can estimate annd compute some dimensions of some part/region in a bitmap ie raster image based on the known dimension else in a region else of the same image
For now need is only in 2 dimension, e.g. to obtain a length of the knife blade region when there is known knife's handle length
and requires 3% max error tolerance
(https://www.farrar-tanner.co.uk/media/catalog/product/c/h/chefkniferedo.jpg?optimize=medium&bg-color=255,255,255&fit=bounds&height=700&width=700&canvas=700:700)
For urgent now only 2D is fine, means image is on 2 axis x,y, really sits aligned into flat plane, not yet have a depth, further 3D axis
This can be done in Gimp using the compass tool. You can configure this tool to measure pixels, inches, millimeters etc.
You can also import this image into FreeCAD, put it on the right scale and then proceed to all kinds of distance measurements :
https://youtu.be/LLhsH_6a2wg
You are welcome.