What is Rasterization?
The process of converting vector graphics (paths, shapes) into a pixel grid. Required for printing on raster output devices (digital printers, screens).
In detail
Rasterization renders vector paths into pixels at a target resolution. Every vector graphic must be rasterized at some point in the pipeline because all final output devices (digital printers, monitors, fabric printers, projectors) work in pixels. The reverse of vectorization. Quality depends on resolution: a vector path rasterized at 300 DPI for textile printing produces sharp output; the same path at 72 DPI produces visible jaggies. Anti-aliasing during rasterization smooths the pixel-stair artifacts at curve edges. Modern tools rasterize on demand at the target DPI rather than storing pre-rasterized files; this preserves quality across multiple output sizes.
Example
A logo drawn as a 24-Bezier-curve SVG rasterizes at 72 DPI into a 144×144 pixel raster (5 KB). The same SVG at 300 DPI rasterizes to 600×600 (45 KB). At 600 DPI for rotary engraving: 1200×1200 (180 KB). All from the same source SVG; each rasterization happens at the moment of output.