| Using the railway network as a flatbed scanner(philo.gay) | |
| 441 points by otherayden 3 days ago | 73 comments | |
tl;dr: A hobbyist mounted an industrial linear scanning camera (Basler ruL2048-19gm, ~19,000 lines/sec) out of trains and ferries to capture ultra-wide "flatbed scanner"-style images, using an accelerometer to correct for variable speed. Major challenges included integrating accelerometer data to derive velocity (GPS proved unreliable), handling parallax by tuning distance-per-pixel per segment, and fixing IR sensitivity and RGB channel misalignment on a color version. Postprocessing was rewritten in NumPy for a modular pipeline, and the resulting gigapixel TIFFs are served via OpenSeadragon tiles. | |
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