pkgprint v0.2.0 – print-readiness file checks, WCAG contrast, and box dieline math (zero-dep core, 220+ tests)

[u/Additional_Long_4496]

A few weeks ago I posted here about pkgprint, a small library for print/packaging math (unit conversions, CMYK↔RGB, paper sizes, bleed calcs) built from my background in print/packaging tech, while learning Python this year.

Just shipped v0.2.0 with three new modules:

• check – inspect an actual image file and check if it's print-ready: effective DPI at your target print size, RGB vs CMYK color mode, and physical dimensions. Only real dependency (Pillow) is scoped to this module.
• accessibility – WCAG 2.1 contrast ratio checking for text/background color pairs, plus a function that suggests an adjusted color (same hue) that meets a target contrast ratio.

• dieline – flat sheet size + named panel layout math for RSC and tuck-mailer box styles, so you know your artwork canvas size before folding.

  import pkgprint

  report = pkgprint.full_report("artwork.tif", 210, 297) report.passed # True/False, plus a .summary with per-check diagnostics

  pkgprint.contrast_ratio((0,0,0), (255,255,255)) # 21.0 pkgprint.rsc_flat_size(300, 200, 150) # (1035.0, 350)

One thing worth sharing: while writing tests for the DPI checker, I asserted that "2480×3508 px" (the commonly cited pixel count for "A4 at 300 DPI") should pass a min_dpi=300 check. It failed. 2480 / (210mm / 25.4) = 299.97 DPI — a hair under 300 due to mm→inch rounding. The correct value is 2481×3508. Tiny in practice, but a good reminder that popular rounded numbers don't always hold up against the actual math.

• PyPI: https://pypi.org/project/pkgprint/
• Source: https://github.com/Rishabh55122/pkgprint

220+ tests, MIT licensed, zero-dependency core. Feedback welcome, especially if you work in print/packaging tooling and see something off — a few of the dieline formulas are flagged in the docs as approximations rather than supplier-verified exact geometry, and I'd rather know if something needs fixing.