[HN Gopher] Show HN: Serverless USGS Historical Topographic map ... ___________________________________________________________________ Show HN: Serverless USGS Historical Topographic map tiles Author : kylebarron Score : 15 points Date : 2021-05-06 22:12 UTC (47 minutes ago) (HTM) web link (kylebarron.dev) (TXT) w3m dump (kylebarron.dev) | pickelchips wrote: | wow | ytdytvhxgydvhh wrote: | Channeling Mitch Hedberg: There used to be hills here. There | still are, but there used to be too. | kylebarron wrote: | Hi all, I was invited to repost this (originally posted last | year) to be included in the second chance pool! | | The USGS created topographic maps by hand from 1884 to 2006 (when | they started making their topographic map series digitally). I | stumbled upon the fact that all 183,000 of their hand-drawn maps | were digitized and uploaded to a public S3 bucket [0] in Cloud- | Optimized GeoTIFF format [1]. | | Because they're in this format, it's possible to quickly mosaic | images _on demand_, in a process called "dynamic tiling" [2]. The | dynamic nature of it gives you a lot more flexibility, because | you aren't creating static tiles once. | | In contrast, the hardest part about this project is the time | variation. The USGS created many different scales of maps at many | different time periods, so figuring out how to combine them into | a few mosaics is quite tricky. With more time invested in this, | it would be ideal to have a search capability to show user- | specified time horizons. (Edit: I talk about this process a bit | more in the Github README [3]). | | More recently I've been spending time doing similar dynamic | tiling projects, but focusing on satellite imagery, to enable | analytic processing of satellite imagery in the browser [4]. | | [0]: `aws s3 ls s3://prd- | tnm/StagedProducts/Maps/HistoricalTopo/GeoTIFF/` | | [1]: https://www.cogeo.org/ | | [2]: https://kylebarron.dev/blog/cog-mosaic/overview | | [3]: https://github.com/kylebarron/usgs-topo-tiler | | [4]: https://www.unfolded.ai/blog/2021-04-28-raster-layer/ ___________________________________________________________________ (page generated 2021-05-06 23:00 UTC)