Daniel J. Dufour

We will discuss the state of [GeoRasterLayer](https://github.com/geotiff/georaster-layer-for-leaflet), a JavaScript library that renders GeoTIFFs directly on a LeafletJS map without a server. This will include an introduction of new features, including the following: - shifting warping off the main thread to a pool of web workers - improved support for extent calculations by increasing vertex density of polygon representations of bounding boxes - high-resolution support by using [geowarp](https://github.com/danieljdufour/geowarp) We will also look to the future and discuss the following: - support for raster types other than GeoTIFF/COG - geozarr support - similar integrations into other web mapping libraries Audience feedback and ideas will be most welcome!

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We will discuss the algorithms inside [geowarp](https://github.com/danieljdufour/geowarp), a high-performance and very low-level JavaScript library for reprojection, resampling and cropping of data from GeoTIFFs and other rasters. This talk will be at the abstract algorithmic level and is suitable for everyone. Here are some of the various algorithms that we will discuss: - [proj-turbo](https://github.com/danieljdufour/proj-turbo): fit an unknown reprojection function to a simple affine transformation - [fast-min](https://github.com/danieljdufour/fast-min)/[fast-max](https://github.com/danieljdufour/fast-max): calculating the range of your raster data leveraging the theoretical limits of the data types - near-vectorize: automatically determining the optimal resampling algorithm based on relative pixel size - [dufour-peyton-intersection](https://github.com/GeoTIFF/dufour-peyton-intersection): calculate the pixels of an arbitrary raster inside an arbitrary polygon - various resampling techniques including nearest, bilinear, vectorization, and box-based statistical methods

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