Yes, I am talking about 2D PDF.
OK, I'll follow your steps, but an imagine has 2 dimension: height and length.
How about the other dimension (wide)? How should I do that?
It depends on what kind of pdf you have. Do you have all the views, eventually with dimensions? In 3DEXPERIENCE you have this (there are also a lot of other examples). In v5 you have somehow a similar license (Sketch Tracer if I remember correctly), you can save pdf as jpg and work on them in CATIA. There are a lot of examples on YouTube.