Is there an official public PNG test-image suite and what permission text does it carry?

PngSuite's licence grants use, copying, modification and distribution of the images for any purpose without fee; it does not separately mention hosting, sale or model training. Curator qualifications: Licence texts/pages read 2026-10-22; no test files downloaded; not legal advice. Suite scope (colour types, corrupted files) from producer reading of the page/README. Limitations: Licence texts/pages read 2026-10-22; no test files downloaded; not legal advice. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

{
  "citations": [
    {
      "url": "http://www.schaik.com/pngsuite/",
      "note": "schaik.com PngSuite.LICENSE (bytes equal pin)"
    }
  ]
}