Export
Verification
Reference comparisons
Specifications
Export
On this page
Scope
SVG output for every gallery example; SVG, PNG, PDF, and Vega output signatures; conversion errors; PNG renderings of 21 plots against baselines.
References
- Reference
- vl-convert 1.9.0; PNG baselines in tests/Visual/baselines
- Versions
- vl-convert 1.9.0, Vega-Lite (vl-convert) 6.1
Data
Method
scripts/evidence-tests.php runs the Pest suite with vl-convert and records each export test. Without vl-convert or the GD extension, the cases are recorded as skipped.
- Check
- End-to-end run with the external program
- Recorded
- 2026-11-02, PHP 8.5.11, Debian GNU/Linux 13 (trixie) (aarch64), commit b9272c6
Tolerances
exact equality
Applies to: SVG output
Starts with <svg and contains a mark group
exact equality
Applies to: Output signatures
<svg, PNG magic bytes, %PDF-, Vega marks, and ExportFailed on conversion errors
exact equality
Applies to: PNG renderings
At most 0.2% of pixels differ by more than 40/255 in the largest channel, and sizes match
x: package value; r: reference value.
Results
4 comparisons in 3 cases: 4 pass, 0 fail, 0 skipped.
By case
| Case | Comparisons | Status |
|---|---|---|
| ExamplesTest | 1 | pass |
| RenderTest | 2 | pass |
| VisualTest | 1 | pass |
Every comparison
| Case | Quantity | Criterion | Values | Status |
|---|---|---|---|---|
| ExamplesTest | renders every gallery example to SVG with vl-convert | exact equality | 46 | pass |
| RenderTest | renders SVG, PNG, PDF, and Vega | exact equality | 1 | pass |
| reports conversion errors | exact equality | 1 | pass | |
| VisualTest | renders as its baseline | exact equality | 21 | pass |
Limitations
Exclusions
- PNG and PDF output are compared by signature and against the visual baselines, not byte for byte.
- The visual plots use Liberation Sans, which vl-convert bundles, and no jitter.
Reproduction
composer install
php scripts/evidence-tests.php- Raw record
- site/verifications/export-checks.json
- Full results
- scripts/evidence-tests.php