raster in, vector out

Examples gallery

Every picture below was traced by swift-potrace itself. Each card lists the exact flags used, so the gallery doubles as a cheat-sheet for the options.

Source raster: Faces

Faces

A tiny hand-drawn portrait — lots of curves and fine detail.

Faces traced with: -i faces.png -o faces.svg

Default trace

potrace -i faces.png -o faces.svg

Straight out of the box: every black region becomes a smooth vector path.

Faces traced with: -i faces.png -o faces.svg --anti-alias --anti-aliasing-algorithm gaussian

Gaussian anti-alias

potrace -i faces.png -o faces.svg --anti-alias --anti-aliasing-algorithm gaussian

Softens the jagged 1-bit edges before tracing for gentler curves.

Faces traced with: -i faces.png -o faces.svg --alphamax 0.0

Sharp corners (alphamax 0)

potrace -i faces.png -o faces.svg --alphamax 0.0

Keeps every corner crisp — nothing gets rounded.

Faces traced with: -i faces.png -o faces.svg --alphamax 1.34

Rounded (alphamax 1.34)

potrace -i faces.png -o faces.svg --alphamax 1.34

The opposite extreme: corners are rounded as much as the tracer allows.

Faces traced with: -i faces.png -o faces.svg --turdsize 50

Drop speckles (turdsize 50)

potrace -i faces.png -o faces.svg --turdsize 50

Discards any blob 50px² or smaller — handy for noisy scans.

Faces traced with: -i faces.png -o faces.svg --invert

Inverted

potrace -i faces.png -o faces.svg --invert

Traces the white regions instead of the black ones.

Source raster: Letters

Letters

Chunky lettering — great for showing how edges are smoothed.

Letters traced with: -i letters.png -o letters.svg

Default trace

potrace -i letters.png -o letters.svg

Faithful vector outline of the pixelated source.

Letters traced with: -i letters.png -o letters.svg

Anti-alias off

potrace -i letters.png -o letters.svg

Hard stair-stepped edges, traced exactly as drawn.

Letters traced with: -i letters.png -o letters.svg --anti-alias --anti-aliasing-algorithm gaussian

Gaussian anti-alias

potrace -i letters.png -o letters.svg --anti-alias --anti-aliasing-algorithm gaussian

Blurs first, so the stair-steps melt into smooth strokes.

Letters traced with: -i letters.png -o letters.svg --turdsize 2

Keep detail (turdsize 2)

potrace -i letters.png -o letters.svg --turdsize 2

The default — tiny features survive.

Letters traced with: -i letters.png -o letters.svg --turdsize 50

Drop speckles (turdsize 50)

potrace -i letters.png -o letters.svg --turdsize 50

Small counters and dots vanish.

Source raster: Abstract

Abstract

Free-form shapes that stress the corner and curve fitting.

Abstract traced with: -i abstract.png -o abstract.svg

Default trace

potrace -i abstract.png -o abstract.svg

A balanced blend of smooth curves and crisp corners.

Abstract traced with: -i abstract.png -o abstract.svg --anti-alias --anti-aliasing-algorithm supersample --anti-alias-supersample-factor 4

Supersample 4×

potrace -i abstract.png -o abstract.svg --anti-alias --anti-aliasing-algorithm supersample --anti-alias-supersample-factor 4

Upsamples 4× before tracing for extra-smooth contours.

Abstract traced with: -i abstract.png -o abstract.svg --alphamax 0.0

Sharp corners (alphamax 0)

potrace -i abstract.png -o abstract.svg --alphamax 0.0

Every vertex stays a hard corner.

Abstract traced with: -i abstract.png -o abstract.svg --alphamax 1.34

Rounded (alphamax 1.34)

potrace -i abstract.png -o abstract.svg --alphamax 1.34

Maximum rounding for a soft, bubbly look.

Download & try it