pdf_io

Create PDF files in Python: convert SVG, draw pages, plot data, render PNG or JPEG. No dependencies: a bundled C library does the heavy lifting.

• Convert SVG to PDF: shapes, paths, text with embedded font subsets, gradients, patterns, clipping, masks, markers, images (PNG, JPEG, and JPEG XL when libjxl is installed) and CSS. With libjxl, images can also be written as JPEG XL (/JXLDecode, as PDFium reads it).
• Draw a scene with pdf_io.draw (drawsvg-style) and save it as PDF, SVG, PNG, JPEG, JPEG XL or AVIF.
• Draw on pages with Document and Canvas (HTML-canvas-style): multiple pages, links, bookmarks, metadata, placed SVG files.
• Lay out text: paragraphs in boxes, justified or not, greedy or Knuth–Plass line breaking, kerning, ligatures, rich text with links, overflow into further boxes.
• Print and archive: CMYK output, spot colors (Separation), ink limit, ICC output intent; PDF/A-2b, 2u and 3b with file attachments.
• Plot: markers at many points, each with its own shape, size, colors and opacity; lines of millions of points; many bars and polygons; heatmaps through color maps (plot_io, built on pdf_io, names them); histograms, kernel densities, contours and swarm layouts computed in C. Coordinates are sequences or any buffer (array, numpy arrays, ...). simplify leaves out what later points hide and decimates long lines, within half a level per pixel.
• Rasterize groups, SVG filters and whole pages (PNG, JPEG, JPEG XL, AVIF) with the same rendering as the PDF.

Install

pip install .

Python 3.11+. No dependencies. Copying the pdf_io/ directory into a project also works.

The C library is bundled, prebuilt for Linux (x86_64, aarch64), Windows (x86_64, arm64) and macOS (arm64); pip compiles nothing. On other platforms, build it with tools/build_native.py and point PDF_IO_NATIVE_LIB at it; without it, plain vector drawing still works and the bulk features (markers, lines, heatmaps, rasterization, PNG, image decoding) raise NativeLibraryError.

Quick start

import pdf_io

pdf_io.convert_file("drawing.svg")                 # writes drawing.pdf
pdf_bytes = pdf_io.svg_to_pdf(svg_text)

pdf_io drawing.svg out.pdf

import pdf_io.draw as draw

d = draw.Drawing(400, 300)                         # CSS pixels, origin top-left
d.append(draw.Circle(200, 150, 80, fill="teal"))
d.append(draw.Text("Hello", 32, 200, 160, text_anchor="middle", fill="white"))
d.save_pdf("hello.pdf")
d.save_svg("hello.svg")

from pdf_io import Document

doc = Document(title="Report")
page = doc.add_page(size="A4")                     # points, origin top-left
page.font_size = 24
page.fill_text("Report", 50, 80)
page.draw_markers(xs, ys, size=4, fill="steelblue", stroke=None)
page.draw_heatmap(values, 50, 300, 400, 250, cmap=["#440154", "#21918c", "#fde725"])
doc.save("report.pdf")

Documentation

• API.md: the complete API, supported SVG features, fonts, rasterization and limits.
• EXAMPLES.md: worked examples (scatter plot, bubble chart, heatmap, multi-page document, rasterization, filters, PNG).

Limits

• Text: no complex-script shaping or bidirectional reordering. Kerning and ligatures apply to laid-out paragraphs only.
• Fonts: WOFF2 and CFF2 (variable OpenType) fonts are not supported.
• Filters can only be reproduced as pixels, so they are opt-in.
• Animation and scripting are ignored: the initial state is drawn.

Development

python -m unittest discover -s tests -t tests

Tests generate their own fonts and images and ignore installed fonts.

mypy                                       # type check (configured in pyproject.toml)

The package ships type annotations (py.typed); mypy is a development tool only.

python tools/regress.py --render --check   # output vs. HEAD on tests/corpus
python tools/regress.py --base main --system
python tools/bench.py                      # timings quoted in API.md

regress.py converts every SVG of the corpus with the working tree and with a git revision and compares the page content streams and rasterized images byte for byte; --render reports pixel differences of changed files and --check reports files poppler warns about.

pip install ziglang==0.15.1                # or: pip install -e .[dev]
python tools/build_native.py               # rebuild pdf_io/_native/bin/*
python tools/build_native.py --check       # binaries match the sources, byte for byte
python tools/crosscheck.py --qemu qemu-aarch64-static   # same pixels on x86_64 and aarch64

The C library and its rules (no libc, no imports, deterministic floating point) are described in pdf_io/_native/README.md, with the sanitizer build and the fuzzers (tests/fuzz_native.py).

python tools/verapdf.py                    # PDF/A validation of the corpus

verapdf.py converts the corpus at each PDF/A level and validates the files with veraPDF (on PATH or --verapdf); the PDF/A unit tests also run veraPDF when it is on PATH.

License

BSD 3-Clause, see LICENSE.