The Making of PD12M: Image Acquisition

PD12M is a 12.4 million image-text dataset made only of images marked with a Public Domain Mark or CC0 license, and its creators say its acquisition method is a deliberate alternative to indiscriminate open-web scraping. The images come from Source.Plus, which pulls about 38 million images mainly from museums and cultural heritage institutions such as Europeana, Wikimedia, and the Smithsonian. Wikimedia uploads were delayed 14 days so the community could flag contested images, and the images are hosted through AWS Open Data, with about 30TB of image data.