Convert GTIFF to AI

Technical note

How GTIFF and AI differ in practice

GTIFF is made of pixels and AI stores geometry, so the conversion traces the image into paths. Once traced, the artwork scales to any size without softening, which is the point of the exercise. It is a reconstruction rather than the original drawing: curves are fitted to the pixel edges, so the cleaner and sharper the source, the closer the paths follow what the designer intended. A line in a GTIFF image is several pixels wide, so tracing it can mean different things and the mode is yours to choose. Centreline returns a single line running down the middle of each stroke, which is what a scanned drawing needs: one entity per line, snappable and dimensionable, rather than a long thin rectangle around it. Outline follows both edges and returns closed shapes, which suits clipart, logos and anything that will be filled or cut. A precision setting controls how closely the traced paths follow the pixel edges. One thing to plan for: vectorised output from this path is black and white, so colour in the GTIFF does not survive as colour in the AI.