vectorcraft/docs/image-trace-quality.md

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Image Trace quality

Last reviewed: 2026-10-13 · Last updated: 2026-10-13 · Change: minor (sub-pixel edges in every mode: outlines 0.31 to 0.09 px off for Default, 0.27 to 0.06 for Black and White Logo)

What Image Trace (crates/trace) makes of images whose right answer is known, measured by a harness and compared with the numbers before each change. Nothing here is a judgement by eye, and nothing is compared with any other product except the open tracer named under Yardstick.

How it is measured

crates/trace/tests/quality draws its own inputs from vector art (no image files), traces each with every built-in preset, and measures the result:

TRACE_QUALITY_REPORT=report.md cargo test --release -p vectorcraft-trace --test quality -- --ignored

Inputs (drawn anti-aliased at 128, 256 and 512 px, and at 256 px also blurred, with compression-like noise, as a scan of ink on cream paper with uneven light and grain, and aliased: one hard sample per pixel, no anti-aliasing):

kind inputs
curved shapes a circle; two ellipses; a rounded badge with a round hole; a letter D with its counter
polygons a triangle, a turned square and a hexagon; a five-pointed star; a letter A with its counter
thin lines five lines 0.5, 1, 2, 3 and 5 units wide (of a 256-unit square), a few degrees off the pixel grid
flat colour art a disc of two halves in different colours that touch; a badge of four colours on white
gradient, photo a smooth two-way gradient with a glow; a photo-like image (soft-edged shaded objects, texture, sensor noise)

The letters are drawn by hand from lines and curves: the repository has no font to set them in.

Columns

column meaning
ΔE the trace drawn again against the source: mean colour difference in Oklab × 100 (black to white is 100)
edge ΔE the same, weighted by how strong an edge the source has at each pixel
off mean, off max distance (px) from the traced outlines to the art's true outlines: wobble and staircase
missed max largest distance (px) from a true outline to the nearest traced one: what was lost
paths, anchors counts, the background's frame aside
× art anchors per anchor point of the art itself (1.00 is as economical as the original)
lines % share of the outline length made of straight segments (100 is right for polygons, 0 for a circle)
corners % share of the art's sharp corners with a traced corner within 1.5 px
kinks anchors where the outline turns by 10° or more away from any true corner
odd colours, odd px paths (and their area) in a colour the art doesn't have: slivers along anti-aliased edges
gap px, overlap px area no path covers, and area covered twice (abutting traces with a white background only)
specks paths under 6 px of area
outside px how far the trace reaches outside the image: a curve that strays

Black-and-white presets trace black: on the scanned variant their ΔE includes the paper's and ink's own colours. – means the measure does not apply; all that nothing was traced.

Baseline and now

Each preset on the inputs it is meant for, all sizes and variants.

Baseline (before any change, main at baf9693f)

preset inputs ΔE edge ΔE off mean off max missed max paths anchors × art lines % corners % kinks odd colours odd px gap px overlap px specks outside px
Default circle, ellipses, badge with a hole, letter D, polygons, star, letter A 2.79 17.15 0.313 1.51 2.52 1.9 14 1.45 34 76 1.4 – – 63.5 67.0 0.0 0.0
High Fidelity Photo gradient, photo-like 2.30 2.63 – – – 3652.6 46866 – 84 – – – – 0.0 – 1169.4 0.3
Low Fidelity Photo gradient, photo-like 2.61 2.94 – – – 128.3 3867 – 42 – – – – 0.0 – 0.0 0.7
3 Colors two touching halves 4.93 11.38 0.482 2.35 89.09 2.1 14 2.31 12 29 2.1 1.6 15418 118.0 87.3 0.0 0.0
6 Colors two touching halves, four-colour badge 0.78 8.82 4.383 83.10 30.11 21.2 270 30.18 51 98 213.8 2.4 272 198.8 194.6 0.0 0.3
16 Colors two touching halves, four-colour badge 0.74 9.02 5.115 86.21 4.32 69.9 923 102.80 58 100 765.9 5.9 670 293.7 329.9 0.0 0.5
Shades of Gray gradient, photo-like 9.29 9.16 – – – 90.8 1921 – 42 – – – – 0.0 – 0.2 0.5
Black and White Logo circle, ellipses, badge with a hole, letter D, polygons, star, letter A 2.76 15.96 0.270 1.76 2.53 1.4 31 3.78 90 81 15.3 – – – – 0.0 0.0
Sketched Art circle, ellipses, badge with a hole, letter D, lines 2.85 17.04 0.302 1.63 105.63 1.8 14 1.34 28 18 1.4 – – – – 0.0 0.0
Silhouettes circle, ellipses, badge with a hole, letter D 3.04 21.41 0.573 2.88 2.89 1.2 10 1.16 9 86 1.4 – – – – 0.0 0.0
Line Art lines 2.77 12.51 0.158 1.13 105.76 5.4 25 1.27 90 – – – – – – 0.0 0.0
Technical Drawing polygons, star, letter A, lines 2.66 13.45 0.201 1.37 105.76 4.8 32 2.23 100 85 5.9 – – – – 0.1 0.0
Flat Logo two touching halves, four-colour badge 0.43 3.53 3.106 88.50 0.78 69.9 352 38.92 38 80 237.0 0.0 0 13.8 – 59.1 0.2

Now (sub-pixel edges)

preset inputs ΔE edge ΔE off mean off max missed max paths anchors × art lines % corners % kinks odd colours odd px gap px overlap px specks outside px
Default circle, ellipses, badge with a hole, letter D, polygons, star, letter A 2.60 10.12 0.091 1.02 2.17 1.9 18 1.81 29 68 0.4 – – 22.2 22.4 0.0 0.0
High Fidelity Photo gradient, photo-like 2.50 2.81 – – – 3636.4 81597 – 25 – – – – 0.0 – 995.3 1.3
Low Fidelity Photo gradient, photo-like 2.59 2.87 – – – 128.3 7277 – 37 – – – – 0.0 – 0.1 0.4
3 Colors two touching halves 4.86 8.48 0.332 2.02 89.49 2.1 38 6.33 11 29 2.6 1.6 15527 50.3 40.4 0.0 0.0
6 Colors two touching halves, four-colour badge 0.61 4.88 4.442 83.47 30.03 21.2 473 53.89 45 95 344.2 2.4 279 68.6 79.0 0.0 0.2
16 Colors two touching halves, four-colour badge 0.60 5.32 5.084 85.85 4.16 69.9 1743 196.62 49 98 1376.4 5.9 612 152.8 141.8 0.2 0.6
Shades of Gray gradient, photo-like 9.29 9.12 – – – 90.7 3183 – 51 – – – – 0.0 – 5.3 0.8
Black and White Logo circle, ellipses, badge with a hole, letter D, polygons, star, letter A 2.58 9.39 0.064 1.00 2.18 1.4 27 2.73 40 67 0.3 – – – – 0.0 0.0
Sketched Art circle, ellipses, badge with a hole, letter D, lines 2.71 12.11 0.195 1.00 105.54 1.8 17 1.49 16 86 0.0 – – – – 0.0 0.0
Silhouettes circle, ellipses, badge with a hole, letter D 2.98 19.28 0.532 2.24 2.24 1.2 14 1.65 12 79 0.1 – – – – 0.0 0.0
Line Art lines 2.65 9.87 0.093 0.89 105.71 5.4 77 3.86 37 – – – – – – 0.1 0.0
Technical Drawing polygons, star, letter A, lines 2.53 9.47 0.086 0.99 105.85 4.8 57 3.73 69 74 0.7 – – – – 0.3 0.0
Flat Logo two touching halves, four-colour badge 0.43 3.53 3.106 88.50 0.78 69.9 352 38.92 38 80 237.0 0.0 0 13.8 – 59.1 0.2

The sections below are the numbers now (sub-pixel edges).

1. Each preset on the inputs it is meant for

All sizes and variants (clean, aliased, blurred, noisy, scanned) of those inputs.

preset inputs ΔE edge ΔE off mean off max missed max paths anchors × art lines % corners % kinks odd colours odd px gap px overlap px specks outside px
Default circle, ellipses, badge with a hole, letter D, polygons, star, letter A 2.60 10.12 0.091 1.02 2.17 1.9 18 1.81 29 68 0.4 – – 22.2 22.4 0.0 0.0
High Fidelity Photo gradient, photo-like 2.50 2.81 – – – 3636.4 81597 – 25 – – – – 0.0 – 995.3 1.3
Low Fidelity Photo gradient, photo-like 2.59 2.87 – – – 128.3 7277 – 37 – – – – 0.0 – 0.1 0.4
3 Colors two touching halves 4.86 8.48 0.332 2.02 89.49 2.1 38 6.33 11 29 2.6 1.6 15527 50.3 40.4 0.0 0.0
6 Colors two touching halves, four-colour badge 0.61 4.88 4.442 83.47 30.03 21.2 473 53.89 45 95 344.2 2.4 279 68.6 79.0 0.0 0.2
16 Colors two touching halves, four-colour badge 0.60 5.32 5.084 85.85 4.16 69.9 1743 196.62 49 98 1376.4 5.9 612 152.8 141.8 0.2 0.6
Shades of Gray gradient, photo-like 9.29 9.12 – – – 90.7 3183 – 51 – – – – 0.0 – 5.3 0.8
Black and White Logo circle, ellipses, badge with a hole, letter D, polygons, star, letter A 2.58 9.39 0.064 1.00 2.18 1.4 27 2.73 40 67 0.3 – – – – 0.0 0.0
Sketched Art circle, ellipses, badge with a hole, letter D, lines 2.71 12.11 0.195 1.00 105.54 1.8 17 1.49 16 86 0.0 – – – – 0.0 0.0
Silhouettes circle, ellipses, badge with a hole, letter D 2.98 19.28 0.532 2.24 2.24 1.2 14 1.65 12 79 0.1 – – – – 0.0 0.0
Line Art lines 2.65 9.87 0.093 0.89 105.71 5.4 77 3.86 37 – – – – – – 0.1 0.0
Technical Drawing polygons, star, letter A, lines 2.53 9.47 0.086 0.99 105.85 4.8 57 3.73 69 74 0.7 – – – – 0.3 0.0
Flat Logo two touching halves, four-colour badge 0.43 3.53 3.106 88.50 0.78 69.9 352 38.92 38 80 237.0 0.0 0 13.8 – 59.1 0.2

2. Each preset on each kind of input (clean, three sizes)

preset inputs ΔE edge ΔE off mean off max missed max paths anchors × art lines % corners % kinks odd colours odd px gap px overlap px specks outside px
Default curved shapes 0.08 3.24 0.057 0.51 0.59 1.8 16 1.72 15 83 0.0 – – 22.7 21.1 0.0 0.0
Default polygons 0.05 2.11 0.036 0.46 1.23 2.0 14 1.24 89 90 0.0 – – 3.1 3.3 0.0 0.0
Default thin lines 0.56 4.77 0.059 0.48 105.57 3.3 22 1.12 42 – – – – 49.1 34.0 0.0 0.0
Default flat colour art 19.95 18.92 0.197 0.64 179.52 1.5 22 1.32 15 0 0.0 – – 24.3 23.0 0.0 0.0
Default gradient, photo 39.13 38.78 – – – 3.2 698 – 57 – – – – 31.2 40.7 0.0 0.3
High Fidelity Photo curved shapes 0.08 3.65 0.243 1.07 0.58 9.9 187 24.84 28 50 0.3 8.7 299 0.0 – 3.8 0.0
High Fidelity Photo polygons 0.13 4.80 0.160 1.14 2.43 3.3 173 16.11 29 78 0.1 1.7 87 0.0 – 0.0 0.0
High Fidelity Photo thin lines 0.73 8.66 0.218 0.93 45.32 13.0 498 24.90 37 – – 6.7 532 0.0 – 7.0 0.0
High Fidelity Photo flat colour art 0.09 2.56 0.351 1.08 0.62 48.2 497 41.54 53 83 9.0 23.2 1119 0.0 – 19.2 0.0
High Fidelity Photo gradient, photo 2.58 2.90 – – – 2926.5 87619 – 27 – – – – 0.0 – 792.5 0.9
Low Fidelity Photo curved shapes 0.09 4.45 0.219 1.02 0.50 5.0 55 6.69 34 100 6.7 3.8 261 0.0 – 0.0 0.0
Low Fidelity Photo polygons 0.15 5.82 0.172 0.97 2.43 3.3 55 5.12 33 80 0.2 1.7 81 0.0 – 0.0 0.0
Low Fidelity Photo thin lines 0.80 9.43 0.238 0.82 45.33 5.0 182 9.08 48 – – 1.3 497 0.0 – 0.0 0.0
Low Fidelity Photo flat colour art 0.11 3.30 0.323 1.04 0.56 20.0 142 10.37 61 100 35.7 7.0 940 0.0 – 0.0 0.0
Low Fidelity Photo gradient, photo 2.67 2.97 – – – 96.2 8623 – 36 – – – – 0.0 – 0.0 0.4
3 Colors curved shapes 0.47 4.85 0.128 1.06 0.52 2.8 30 3.42 20 100 1.7 1.0 86 35.0 41.9 0.0 0.0
3 Colors polygons 0.62 4.45 0.080 1.03 1.50 2.4 28 2.58 43 81 0.0 0.4 16 10.9 13.4 0.0 0.0
3 Colors thin lines 0.74 7.45 0.129 1.06 45.26 5.0 60 3.00 37 – – 3.7 1123 84.3 53.1 0.0 0.0
3 Colors flat colour art 3.77 6.61 0.191 1.35 89.46 2.3 26 1.90 34 38 0.3 1.5 15138 35.8 28.5 0.2 0.0
3 Colors gradient, photo 7.85 7.91 – – – 4.3 611 – 47 – – – – 23.6 30.1 0.0 0.2
6 Colors curved shapes 0.11 4.81 0.186 0.96 0.50 3.6 56 6.76 25 100 2.8 1.8 155 30.9 29.4 0.0 0.0
6 Colors polygons 0.12 4.81 0.128 0.80 1.51 3.1 56 5.23 35 81 0.2 1.1 47 22.2 20.6 0.0 0.0
6 Colors thin lines 0.91 9.26 0.160 0.86 45.36 4.0 132 6.60 40 – – 1.7 409 53.6 44.0 0.0 0.0
6 Colors flat colour art 0.19 2.98 0.216 1.29 0.51 5.0 60 5.27 56 100 3.0 1.5 170 27.9 39.3 0.0 0.0
6 Colors gradient, photo 5.50 5.70 – – – 15.5 1421 – 38 – – – – 54.3 75.6 0.0 0.2
16 Colors curved shapes 0.09 4.14 0.200 0.97 0.50 4.2 91 11.37 29 100 5.3 2.5 168 21.8 21.7 0.0 0.0
16 Colors polygons 0.13 5.20 0.138 0.97 2.43 3.1 81 7.53 33 81 0.3 1.1 52 15.3 18.5 0.0 0.0
16 Colors thin lines 0.79 9.20 0.187 0.82 45.35 4.0 287 14.35 35 – – 1.3 362 24.9 22.6 0.0 0.0
16 Colors flat colour art 0.12 3.16 0.279 0.99 0.45 7.5 127 10.37 61 100 7.5 3.0 321 59.9 31.8 0.0 0.0
16 Colors gradient, photo 3.23 3.58 – – – 72.0 4652 – 30 – – – – 165.5 258.6 0.0 0.8
Shades of Gray curved shapes 0.11 4.71 0.216 1.00 0.59 5.1 49 6.02 30 100 5.9 3.8 252 0.0 – 0.0 0.0
Shades of Gray polygons 0.11 4.32 0.147 0.80 1.39 3.3 45 4.09 36 82 0.0 1.7 76 0.0 – 0.0 0.0
Shades of Gray thin lines 0.81 8.80 0.239 0.70 45.31 5.0 141 7.03 44 – – 1.3 499 0.0 – 0.0 0.0
Shades of Gray flat colour art 7.35 10.90 0.357 1.42 179.46 13.3 121 10.08 42 50 30.8 12.7 39181 0.0 – 0.0 0.0
Shades of Gray gradient, photo 9.73 9.60 – – – 82.0 3181 – 51 – – – – 0.0 – 2.2 0.8
Black and White Logo curved shapes 0.04 1.52 0.024 0.50 0.60 1.2 21 2.25 21 75 0.0 – – – – 0.0 0.0
Black and White Logo polygons 0.04 1.83 0.030 0.45 1.23 1.7 15 1.34 89 90 0.0 – – – – 0.0 0.0
Black and White Logo thin lines 0.50 4.22 0.065 0.50 77.21 10.3 66 3.30 65 – – – – – – 0.0 0.0
Black and White Logo flat colour art 19.94 18.72 0.192 0.31 179.52 1.0 19 1.18 24 0 0.0 – – – – 0.0 0.0
Black and White Logo gradient, photo 39.11 38.71 – – – 9.0 676 – 72 – – – – – – 0.0 0.0
Sketched Art curved shapes 0.13 5.54 0.107 0.41 0.41 1.2 13 1.43 17 100 0.0 – – – – 0.0 0.0
Sketched Art polygons 0.13 5.00 0.092 0.51 1.07 1.7 14 1.24 82 86 0.0 – – – – 0.0 0.0
Sketched Art thin lines 0.38 4.99 0.102 0.80 52.57 4.3 37 1.87 35 – – – – – – 0.0 0.0
Sketched Art flat colour art 20.32 20.95 0.175 0.89 179.64 1.5 22 1.34 18 0 0.0 – – – – 0.0 0.0
Sketched Art gradient, photo 45.53 45.37 – – – 1.0 251 – 47 – – – – – – 0.0 0.3
Silhouettes curved shapes 0.34 14.15 0.274 0.66 0.66 1.2 12 1.36 17 100 0.0 – – – – 0.0 0.0
Silhouettes polygons 0.35 14.03 0.263 0.67 0.70 1.7 14 1.26 76 85 0.0 – – – – 0.0 0.0
Silhouettes thin lines 1.05 16.01 0.308 1.09 18.10 5.0 42 2.08 40 – – – – – – 0.0 0.0
Silhouettes flat colour art 23.86 34.06 0.226 0.77 188.38 1.0 10 0.76 26 0 0.0 – – – – 0.0 0.0
Silhouettes gradient, photo 61.56 61.35 – – – 0.2 2 – 47 – – – – – – 0.0 0.6
Line Art curved shapes 0.05 1.93 0.033 0.53 0.63 1.2 17 1.86 19 75 0.0 – – – – 0.0 0.0
Line Art polygons 0.05 1.87 0.031 0.46 1.23 1.7 14 1.27 89 90 0.0 – – – – 0.0 0.0
Line Art thin lines 0.54 4.38 0.049 0.47 105.71 3.3 33 1.67 42 – – – – – – 0.0 0.0
Line Art flat colour art 19.94 18.69 0.192 0.49 179.52 1.0 46 2.55 23 0 0.0 – – – – 0.0 0.0
Line Art gradient, photo 39.11 38.71 – – – 7.7 490 – 59 – – – – – – 0.0 0.1
Technical Drawing curved shapes 0.04 1.52 0.024 0.50 0.60 1.2 21 2.25 21 75 0.0 – – – – 0.0 0.0
Technical Drawing polygons 0.04 1.83 0.030 0.45 1.23 1.7 15 1.34 89 90 0.0 – – – – 0.0 0.0
Technical Drawing thin lines 0.39 3.88 0.075 0.50 55.75 15.3 81 4.05 76 – – – – – – 0.3 0.0
Technical Drawing flat colour art 19.94 18.72 0.192 0.31 179.52 1.0 19 1.18 24 0 0.0 – – – – 0.0 0.0
Technical Drawing gradient, photo 39.08 38.69 – – – 20.0 964 – 79 – – – – – – 2.0 0.1
Flat Logo curved shapes 0.06 2.14 0.036 0.25 0.25 1.8 31 3.38 19 100 0.0 0.0 0 6.8 – 0.0 0.0
Flat Logo polygons 0.09 3.44 0.060 0.35 1.03 2.0 35 3.17 67 94 0.0 0.0 0 6.8 – 0.0 0.0
Flat Logo thin lines 1.17 11.78 0.050 0.49 all 3.0 189 9.45 28 – – 0.0 0 5467.1 – 0.0 0.0
Flat Logo flat colour art 0.07 1.53 0.065 0.31 0.27 3.0 36 3.51 47 100 0.0 0.0 0 6.8 – 0.0 0.0
Flat Logo gradient, photo refused

3. Each preset on its inputs, by variant (256 px)

preset variant ΔE edge ΔE off mean off max missed max paths anchors × art lines % corners % kinks odd colours odd px gap px overlap px specks outside px
Default clean 0.07 2.76 0.048 0.51 1.23 1.9 15 1.52 46 88 0.0 – – 14.3 13.5 0.0 0.0
Default aliased 0.39 21.13 0.229 1.02 1.34 1.9 14 1.42 21 98 0.0 – – 52.7 52.9 0.0 0.0
Default blurred 0.82 16.65 0.078 0.86 2.17 1.9 26 2.50 7 19 1.6 – – 23.0 23.6 0.0 0.0
Default noisy 1.74 4.55 0.052 0.57 1.23 1.9 16 1.64 38 67 0.0 – – 16.2 15.1 0.0 0.0
Default scanned 15.06 20.24 0.134 0.87 2.17 1.9 26 2.53 0 25 1.0 – – 20.8 24.7 0.0 0.0
High Fidelity Photo clean 2.58 2.90 – – – 2926.5 87619 – 27 – – – – 0.0 – 792.5 0.9
High Fidelity Photo aliased 2.55 2.88 – – – 2686.0 56883 – 22 – – – – 0.0 – 695.5 0.9
High Fidelity Photo blurred 2.05 2.50 – – – 1486.5 37982 – 22 – – – – 0.0 – 205.5 1.3
High Fidelity Photo noisy 3.10 3.37 – – – 7294.5 118138 – 26 – – – – 0.0 – 2051.5 0.6
High Fidelity Photo scanned 2.04 2.22 – – – 5208.5 95324 – 24 – – – – 0.0 – 1637.0 0.4
Low Fidelity Photo clean 2.67 2.97 – – – 96.2 8623 – 36 – – – – 0.0 – 0.0 0.4
Low Fidelity Photo aliased 2.62 2.91 – – – 125.5 5195 – 34 – – – – 0.0 – 0.0 0.2
Low Fidelity Photo blurred 2.67 3.13 – – – 151.5 4525 – 33 – – – – 0.0 – 0.0 0.2
Low Fidelity Photo noisy 2.75 2.94 – – – 106.5 7104 – 39 – – – – 0.0 – 0.0 0.2
Low Fidelity Photo scanned 2.07 2.19 – – – 226.0 8249 – 40 – – – – 0.0 – 0.5 0.2
3 Colors clean 4.62 7.50 0.106 0.35 89.46 1.3 11 1.78 13 33 0.0 0.7 10577 33.4 32.3 0.0 0.0
3 Colors aliased 0.18 9.81 0.236 0.74 0.56 2.0 7 1.17 39 100 0.0 0.0 0 123.2 82.4 0.0 0.0
3 Colors blurred 6.92 10.46 0.848 2.02 87.75 4.0 122 20.33 0 0 10.0 4.0 25697 51.3 37.6 0.0 0.0
3 Colors noisy 7.21 9.91 0.112 0.31 89.49 1.0 12 2.00 0 0 0.0 1.0 25398 37.8 18.2 0.0 0.0
3 Colors scanned 5.86 6.64 0.814 1.49 88.54 4.0 93 15.50 0 0 8.0 4.0 25863 39.3 47.4 0.0 0.0
6 Colors clean 0.19 2.98 0.216 1.29 0.51 5.0 60 5.27 56 100 3.0 1.5 170 27.9 39.3 0.0 0.0
6 Colors aliased 0.31 10.53 0.291 1.00 1.00 3.0 26 1.91 42 100 0.0 0.0 0 82.6 74.0 0.0 0.0
6 Colors blurred 0.76 6.94 0.685 1.52 1.02 10.0 204 22.77 43 100 23.5 6.0 976 49.1 39.8 0.0 0.0
6 Colors noisy 1.20 3.58 20.366 79.78 30.03 99.0 2064 245.68 30 100 1822.5 3.0 297 191.1 209.1 0.0 0.2
6 Colors scanned 1.47 4.15 9.100 83.47 0.94 21.5 835 91.04 30 62 554.5 3.0 172 73.9 112.0 0.0 0.2
16 Colors clean 0.12 3.16 0.279 0.99 0.45 7.5 127 10.37 61 100 7.5 3.0 321 59.9 31.8 0.0 0.0
16 Colors aliased 0.30 10.39 0.274 1.00 1.00 3.0 34 2.34 43 100 0.0 0.0 0 77.3 51.7 0.0 0.0
16 Colors blurred 0.59 8.94 0.949 2.58 1.73 26.5 421 35.52 57 100 102.5 10.0 1155 149.8 121.6 0.0 0.0
16 Colors noisy 1.31 4.52 17.093 82.18 4.16 238.5 4758 593.71 29 100 4008.5 4.5 607 313.9 328.8 0.0 0.2
16 Colors scanned 1.63 3.93 16.438 85.85 3.01 199.0 6606 713.67 29 88 5501.0 18.0 1561 349.0 394.9 1.5 0.6
Shades of Gray clean 9.73 9.60 – – – 82.0 3181 – 51 – – – – 0.0 – 2.2 0.8
Shades of Gray aliased 9.73 9.58 – – – 80.0 2438 – 54 – – – – 0.0 – 3.0 0.8
Shades of Gray blurred 9.69 9.39 – – – 62.0 1652 – 50 – – – – 0.0 – 1.0 0.7
Shades of Gray noisy 9.79 9.52 – – – 132.0 3813 – 51 – – – – 0.0 – 9.0 0.8
Shades of Gray scanned 6.64 6.56 – – – 115.0 4832 – 48 – – – – 0.0 – 17.5 0.5
Black and White Logo clean 0.04 1.65 0.027 0.50 1.23 1.4 18 1.86 50 86 0.0 – – – – 0.0 0.0
Black and White Logo aliased 0.39 20.41 0.176 1.00 1.34 1.4 24 2.47 53 98 0.0 – – – – 0.0 0.0
Black and White Logo blurred 0.81 16.37 0.047 0.80 2.18 1.4 39 3.78 23 19 1.0 – – – – 0.0 0.0
Black and White Logo noisy 1.72 3.90 0.028 0.50 1.23 1.4 21 2.14 41 67 0.0 – – – – 0.0 0.0
Black and White Logo scanned 15.05 20.10 0.116 0.82 2.17 1.4 53 5.13 11 25 0.9 – – – – 0.0 0.0
Sketched Art clean 0.18 5.43 0.106 0.80 52.57 1.9 18 1.52 20 100 0.0 – – – – 0.0 0.0
Sketched Art aliased 0.49 20.73 0.237 1.00 105.54 1.6 10 1.02 27 100 0.0 – – – – 0.0 0.0
Sketched Art blurred 1.07 19.51 0.264 0.66 105.48 1.6 18 1.57 13 50 0.0 – – – – 0.0 0.0
Sketched Art noisy 1.75 5.86 0.108 0.95 1.03 2.0 18 1.53 13 100 0.0 – – – – 0.0 0.0
Sketched Art scanned 15.11 22.41 0.438 0.85 105.28 1.6 20 1.73 1 50 0.0 – – – – 0.0 0.0
Silhouettes clean 0.34 14.15 0.274 0.66 0.66 1.2 12 1.36 17 100 0.0 – – – – 0.0 0.0
Silhouettes aliased 0.42 23.04 0.353 1.03 1.03 1.2 9 1.05 9 100 0.0 – – – – 0.0 0.0
Silhouettes blurred 1.23 28.51 0.803 1.42 1.84 1.2 17 1.91 13 50 0.0 – – – – 0.0 0.0
Silhouettes noisy 2.10 10.67 0.274 0.64 0.64 1.2 12 1.34 7 100 0.0 – – – – 0.0 0.0
Silhouettes scanned 16.05 30.27 1.472 2.24 2.24 1.2 23 3.15 3 0 1.0 – – – – 0.0 0.0
Line Art clean 0.54 4.38 0.049 0.47 105.71 3.3 33 1.67 42 – – – – – – 0.0 0.0
Line Art aliased 0.66 14.39 0.110 0.74 55.44 14.0 60 3.00 87 – – – – – – 0.0 0.0
Line Art blurred 1.63 17.25 0.137 0.89 105.61 3.0 139 6.95 3 – – – – – – 0.0 0.0
Line Art noisy 1.03 4.27 0.043 0.48 56.06 8.0 56 2.80 41 – – – – – – 1.0 0.0
Line Art scanned 13.60 20.04 0.212 0.84 105.58 3.0 186 9.30 0 – – – – – – 0.0 0.0
Technical Drawing clean 0.13 2.34 0.041 0.50 55.75 5.1 32 2.02 86 90 0.0 – – – – 0.1 0.0
Technical Drawing aliased 0.43 18.55 0.206 0.99 55.44 6.8 34 2.08 95 97 0.0 – – – – 0.0 0.0
Technical Drawing blurred 1.05 16.72 0.088 0.95 105.75 2.0 97 6.62 28 25 2.7 – – – – 0.0 0.0
Technical Drawing noisy 1.39 3.88 0.042 0.50 31.23 7.8 46 2.76 81 90 0.0 – – – – 1.8 0.0
Technical Drawing scanned 14.45 20.15 0.145 0.92 105.85 2.0 126 8.57 22 36 2.3 – – – – 0.0 0.0
Flat Logo clean 0.07 1.53 0.065 0.31 0.27 3.0 36 3.51 47 100 0.0 0.0 0 6.8 – 0.0 0.0
Flat Logo aliased 0.13 5.87 0.218 0.65 0.65 3.0 31 1.96 44 50 0.0 0.0 0 5.8 – 0.0 0.0
Flat Logo blurred 0.54 8.33 0.052 0.62 0.78 3.0 28 1.78 43 50 0.0 0.0 0 5.8 – 0.0 0.0
Flat Logo noisy 0.81 1.77 0.076 0.39 0.32 3.5 44 2.63 31 100 1.0 0.0 0 6.9 – 0.5 0.0
Flat Logo scanned 1.31 4.15 21.204 88.50 0.66 470.5 2251 255.53 11 62 1658.0 0.0 0 58.0 – 413.5 0.2

4. Yardstick

Inkscape 1.4.2's Trace Bitmap, run as a black box through its object-trace action (two scans, background removed, its other settings as they come) on the same one-colour drawings, and its SVG output measured by the same code. Compare with the black-and-white presets on the same kinds of input in section 2 and 3.

inputs variant ΔE edge ΔE off mean off max missed max paths anchors × art lines % corners % kinks odd colours odd px gap px overlap px specks outside px
curved shapes clean 0.25 11.05 0.198 0.97 0.97 1.0 15 1.98 11 83 1.8 – – – – 0.0 0.0
curved shapes aliased 0.38 20.79 0.192 0.88 0.88 1.0 16 1.88 14 50 1.8 – – – – 0.0 0.0
curved shapes blurred 0.79 16.57 0.182 0.86 1.14 1.0 15 1.84 6 0 1.8 – – – – 0.0 0.0
curved shapes noisy 2.01 8.14 0.191 0.93 0.93 1.0 17 2.06 10 75 2.8 – – – – 0.0 0.0
curved shapes scanned 15.31 20.22 0.191 0.97 1.14 1.0 16 1.98 7 0 2.0 – – – – 0.0 0.0
polygons clean 0.16 6.45 0.124 1.26 2.36 1.0 21 1.93 27 34 0.0 – – – – 0.0 0.0
polygons aliased 0.35 18.33 0.150 1.22 2.35 1.0 20 1.81 20 28 0.0 – – – – 0.0 0.0
polygons blurred 0.90 17.54 0.190 1.20 2.56 1.0 19 1.75 0 0 0.0 – – – – 0.0 0.0
polygons noisy 1.62 6.05 0.119 1.22 2.32 1.0 22 2.01 29 19 0.0 – – – – 0.0 0.0
polygons scanned 14.75 20.30 0.170 1.49 2.55 1.0 21 1.90 4 3 0.0 – – – – 0.0 0.0
thin lines clean 0.44 6.05 0.109 0.98 76.81 1.0 34 1.72 2 – – – – – – 0.0 0.0
thin lines aliased 0.74 16.37 0.099 1.17 55.97 1.0 22 1.10 6 – – – – – – 0.0 0.0
thin lines blurred 1.72 18.80 0.254 0.81 106.00 1.0 18 0.90 0 – – – – – – 0.0 0.0
thin lines noisy 1.02 6.25 0.112 1.00 37.89 1.0 25 1.25 0 – – – – – – 0.0 0.0
thin lines scanned 28.94 46.83 12.147 43.11 20.79 1.0 2763 138.15 2 – – – – – – 0.0 0.1

5. Cost

One trace at a time on this machine (all cores); memory is the peak allocated above the image itself. A trace of more than 2,000,000 anchors is refused, as in the app.

preset image megapixels result
Default photo-like 1 0.08 s, 29 paths, 7947 anchors, 15 MB
Default four-colour badge 1 0.03 s, 3 paths, 106 anchors, 15 MB
High Fidelity Photo photo-like 1 2.05 s, 51279 paths, 1476202 anchors, 209 MB
High Fidelity Photo four-colour badge 1 0.06 s, 147 paths, 1700 anchors, 111 MB
Low Fidelity Photo photo-like 1 0.19 s, 612 paths, 91647 anchors, 133 MB
Low Fidelity Photo four-colour badge 1 0.05 s, 85 paths, 548 anchors, 86 MB
3 Colors photo-like 1 0.05 s, 9 paths, 5249 anchors, 22 MB
3 Colors four-colour badge 1 0.04 s, 6 paths, 128 anchors, 21 MB
6 Colors photo-like 1 0.05 s, 53 paths, 13454 anchors, 38 MB
6 Colors four-colour badge 1 0.04 s, 7 paths, 153 anchors, 39 MB
16 Colors photo-like 1 0.13 s, 398 paths, 49771 anchors, 89 MB
16 Colors four-colour badge 1 0.05 s, 16 paths, 527 anchors, 89 MB
Shades of Gray photo-like 1 0.10 s, 447 paths, 31068 anchors, 52 MB
Shades of Gray four-colour badge 1 0.04 s, 36 paths, 400 anchors, 52 MB
Black and White Logo photo-like 1 0.06 s, 71 paths, 9067 anchors, 9 MB
Black and White Logo four-colour badge 1 0.02 s, 1 paths, 58 anchors, 8 MB
Sketched Art photo-like 1 0.06 s, 5 paths, 3207 anchors, 9 MB
Sketched Art four-colour badge 1 0.03 s, 2 paths, 145 anchors, 8 MB
Silhouettes photo-like 1 0.05 s, 2 paths, 851 anchors, 11 MB
Silhouettes four-colour badge 1 0.03 s, 1 paths, 29 anchors, 9 MB
Line Art photo-like 1 0.07 s, 54 paths, 4751 anchors, 9 MB
Line Art four-colour badge 1 0.03 s, 1 paths, 243 anchors, 8 MB
Technical Drawing photo-like 1 0.07 s, 221 paths, 10646 anchors, 9 MB
Technical Drawing four-colour badge 1 0.02 s, 1 paths, 58 anchors, 8 MB
Flat Logo photo-like 1 refused after 0.10 s (not flat art), 40 MB
Flat Logo four-colour badge 1 0.76 s, 5 paths, 78 anchors, 146 MB
Default photo-like 4 0.22 s, 48 paths, 20717 anchors, 60 MB
Default four-colour badge 4 0.12 s, 3 paths, 148 anchors, 64 MB
High Fidelity Photo photo-like 4 refused after 3.98 s (over 2,000,000 anchors), 818 MB
High Fidelity Photo four-colour badge 4 0.22 s, 225 paths, 2758 anchors, 530 MB
Low Fidelity Photo photo-like 4 0.52 s, 1499 paths, 196617 anchors, 493 MB
Low Fidelity Photo four-colour badge 4 0.19 s, 88 paths, 780 anchors, 352 MB
3 Colors photo-like 4 0.20 s, 22 paths, 13682 anchors, 88 MB
3 Colors four-colour badge 4 0.14 s, 5 paths, 153 anchors, 84 MB
6 Colors photo-like 4 0.21 s, 100 paths, 32737 anchors, 152 MB
6 Colors four-colour badge 4 0.15 s, 7 paths, 191 anchors, 152 MB
16 Colors photo-like 4 0.40 s, 1236 paths, 130559 anchors, 393 MB
16 Colors four-colour badge 4 0.22 s, 17 paths, 917 anchors, 324 MB
Shades of Gray photo-like 4 0.37 s, 1289 paths, 83191 anchors, 199 MB
Shades of Gray four-colour badge 4 0.19 s, 41 paths, 450 anchors, 197 MB
Black and White Logo photo-like 4 0.26 s, 208 paths, 25916 anchors, 36 MB
Black and White Logo four-colour badge 4 0.10 s, 1 paths, 64 anchors, 36 MB
Sketched Art photo-like 4 0.26 s, 9 paths, 6875 anchors, 36 MB
Sketched Art four-colour badge 4 0.10 s, 2 paths, 279 anchors, 36 MB
Silhouettes photo-like 4 0.20 s, 2 paths, 2133 anchors, 44 MB
Silhouettes four-colour badge 4 0.10 s, 1 paths, 32 anchors, 36 MB
Line Art photo-like 4 0.23 s, 127 paths, 12595 anchors, 36 MB
Line Art four-colour badge 4 0.09 s, 1 paths, 465 anchors, 36 MB
Technical Drawing photo-like 4 0.23 s, 931 paths, 33946 anchors, 36 MB
Technical Drawing four-colour badge 4 0.10 s, 1 paths, 64 anchors, 36 MB
Flat Logo photo-like 4 refused after 0.12 s (not flat art), 40 MB
Flat Logo four-colour badge 4 0.73 s, 5 paths, 69 anchors, 146 MB
Default photo-like 16 1.19 s, 127 paths, 46199 anchors, 256 MB
Default four-colour badge 16 0.50 s, 3 paths, 284 anchors, 240 MB
High Fidelity Photo photo-like 16 refused after 8.58 s (over 2,000,000 anchors), 3320 MB
High Fidelity Photo four-colour badge 16 1.11 s, 438 paths, 4419 anchors, 2404 MB
Low Fidelity Photo photo-like 16 2.12 s, 8558 paths, 699119 anchors, 1910 MB
Low Fidelity Photo four-colour badge 16 1.18 s, 105 paths, 1089 anchors, 1556 MB
3 Colors photo-like 16 1.08 s, 87 paths, 32157 anchors, 352 MB
3 Colors four-colour badge 16 0.70 s, 6 paths, 227 anchors, 336 MB
6 Colors photo-like 16 0.98 s, 476 paths, 86962 anchors, 608 MB
6 Colors four-colour badge 16 0.68 s, 11 paths, 290 anchors, 600 MB
16 Colors photo-like 16 1.55 s, 7432 paths, 407078 anchors, 1574 MB
16 Colors four-colour badge 16 0.86 s, 23 paths, 1707 anchors, 1348 MB
Shades of Gray photo-like 16 1.24 s, 5996 paths, 256732 anchors, 789 MB
Shades of Gray four-colour badge 16 1.03 s, 41 paths, 681 anchors, 684 MB
Black and White Logo photo-like 16 1.20 s, 1128 paths, 77629 anchors, 144 MB
Black and White Logo four-colour badge 16 0.46 s, 1 paths, 103 anchors, 128 MB
Sketched Art photo-like 16 1.13 s, 15 paths, 17817 anchors, 144 MB
Sketched Art four-colour badge 16 0.47 s, 2 paths, 478 anchors, 128 MB
Silhouettes photo-like 16 1.36 s, 3 paths, 4891 anchors, 176 MB
Silhouettes four-colour badge 16 0.53 s, 1 paths, 44 anchors, 144 MB
Line Art photo-like 16 1.20 s, 713 paths, 64481 anchors, 144 MB
Line Art four-colour badge 16 0.49 s, 1 paths, 786 anchors, 128 MB
Technical Drawing photo-like 16 1.45 s, 4578 paths, 114292 anchors, 144 MB
Technical Drawing four-colour badge 16 0.48 s, 1 paths, 103 anchors, 128 MB
Flat Logo photo-like 16 refused after 0.13 s (not flat art), 40 MB
Flat Logo four-colour badge 16 1.09 s, 5 paths, 67 anchors, 146 MB

Revision history

date change
2026-10-13 Sub-pixel edges and the outline fitter in Black and White, Grayscale and Color; the harness gains an aliased variant and an "outside px" column, so the baseline was measured again with it (same tracer, main at baf9693f)
2026-10-12 The harness and the baseline: every preset measured before any change to the tracer