Taking measurements from an image file

Hi all,

I have been given a few jpgs and I'm assured they are to scale @ 1:25. I
need to take measurements from these, is there a program out there
(preferably freeware that will scale the drawing then any dim i want I
can just take from the jpg? I have a few measurements dotted around the
image so I can reference it within the program to the correct scale.

thanks for any help received

Shiva

 

If you have AutoCAD or any other CADing software, import the jpg into a
drawing. Scale the jpg to a known dimension and then you can dimension to
your hearts content.

Chris

 

Well, if the images are 1:25, why not just print at 1:1 and then multiply
your measurements by 25?

Or you could import the images to AutoCAD (IMAGE command), then SCALE with
the Reference option to 1:1 in your drawing.
___

 

There is no such thing as scale in a bitmap, unless you know the resolution
when it was made. If there is a known distance on the drawing you can import
it into AutoCAD and scale it until AutoCAD reports the distance is the same
as the known, or specified distance. You don't really need any software at
all, but you have nothing to snap to so all dimension you extract from the
bitmap will be approximations.

 

The only reason I wanted to know if there was a program is because the guy i
am doing this for wants a copy, and I can't exactly give him a copy of
autocad, should have been clearer in my OP. Is there a free or really cheap
program that acts similar to the image refernce in autocad? I've searched
and I'm not sure there is such a thing.

Thanks for your replies anyway
Shiva

 

try looking at IntelliCAD cheaper than AutoCAD and you can download a
30 day version to play with.

 

Yep. And no, there's no free lunch.
___

 

you could change it to a pdf that he can see through adobe.

 

If you know the DPI (resolution) setting with which the bitmap was made then
most any bitmap program will do the job. You just have to print them at the
same resolution.