[HN Gopher] Show HN: Serverless USGS Historical Topographic map ...
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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/
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(page generated 2021-05-06 23:00 UTC)