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"path": "/2026/05/16/21st-century-punch-cards-are-3d-printed-and-read-by-opencv/",
"publishedAt": "2026-05-16T20:00:55.000Z",
"site": "https://hackaday.com",
"tags": [
"classic hacks",
"computer hacks",
"3d print",
"computer vision",
"opencv",
"punch card",
"…read more"
],
"textContent": "While a punch card is perhaps the lowest-density storage medium available, it has some distinct advantages. As [Bitroller] points out in the write-up of his punch card project, if he …read more",
"title": "21st Century Punch Cards are 3D Printed and Read By OpenCV"
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