svg-to-raster

SVG to Raster

Rasterize SVG files to PNG / PDF / PS via CairoSVG. Runs from the plugin's uv venv — no system Python pollution.

When to use

• Convert logo / icon / diagram SVGs to PNG for use in slides, social, or pipelines that don't accept SVG.
• Render an SVG at multiple resolutions (e.g. 1×, 2×, 3× for app assets).
• Bake an SVG into a PDF for print or archival.

Do not use this skill when:

• Source is already raster — wrong direction; use vectorize instead.
• You need to edit the SVG — CairoSVG is render-only.
• The SVG uses advanced filters / unsupported CSS — CairoSVG covers SVG 1.1 well but newer features may not render. Inspect output and warn the user.

Inputs

1. Input — SVG file or directory. Required.
2. Format — png (default), pdf, ps.
3. Output dir — default: <input-dir>/<format>/. Never overwrites originals.
4. Scale — multiplier on the SVG's intrinsic size. Default 1.0. Use 2.0, 3.0 for hi-DPI.
5. Width / Height — explicit pixel dimensions (overrides scale). Pass one to preserve aspect; both to force.
6. DPI — for PDF/PS output. Default 96.
7. Background — default transparent. Pass a CSS colour (#ffffff, white) for solid fill.
8. Recursive — --recursive for directory descent.

Procedure

1. Resolve venv: VENV_DIR="${CLAUDE_USER_DATA:-${XDG_DATA_HOME:-$HOME/.local/share}/claude-plugins}/image-production/venv".

2. Verify cairosvg is importable in the venv:

   "$VENV_DIR/bin/python" -c "import cairosvg" 2>&1
   

   If missing → point at install-deps. If it imports but raises a libcairo error, surface the system-lib install command (sudo apt install libcairo2 / brew install cairo).

3. Enumerate *.svg inputs (case-insensitive). Skip non-SVG with note.

4. For each file, call CairoSVG via Python one-liner (keeps the skill self-contained — no helper script needed):

   "$VENV_DIR/bin/python" -c "
   import cairosvg, sys
   kwargs = {'url': sys.argv[1], 'write_to': sys.argv[2]}
   # Inject scale / dimensions / dpi / background as appropriate
   cairosvg.svg2png(**kwargs)  # or svg2pdf / svg2ps
   " "<input.svg>" "<output.png>"
   

   Function map: png → svg2png, pdf → svg2pdf, ps → svg2ps.

   Optional kwargs: scale=<float>, output_width=<int>, output_height=<int>, dpi=<int>, background_color="<css>".

5. Track file sizes and any render warnings (CairoSVG prints to stderr for unsupported features).

Output

• Rasterized files at <output-dir>/.
• Summary:
  • Files processed / failed.
  • Per-file: source dimensions → output dimensions, output size.
  • Any render warnings (unsupported SVG features).

Notes

• CairoSVG is LGPL-3.0; using it as a CLI dependency is fine, no licence contagion.
• For multi-resolution batch (e.g. app icon set), call this skill multiple times with different --scale values, or wrap in a small loop.
• If you need true SVG editing or advanced filter support, look at Inkscape CLI (inkscape --export-type=png). CairoSVG is the lighter-weight pure-Python option.
• Animated SVG (SMIL) is not supported — CairoSVG renders the initial frame only.