Read Stack of GeoSpatial Raster Data
npm install georaster-stack
npm install georaster-stack
$3
js
import { GeoExtent } from "geo-extent";
import { GeoRasterStack } from "georaster-stack/web";const stack = await GeoRasterStack.init({
// multiple sources
// they can even be in different projections!
sources: [
"https://example.org/red.tiff",
"https://example.org/green.tiff",
"https://example.org/blue.tiff"
]
});
const result = await stack.read({
// instance of GeoExtent (https://www.npmjs.com/package/geo-extent)
// an extent is a bbox with a spatial reference system
extent: new GeoExtent([-122.49755859375, 38.8520508, -120.06958007812499, 40.697299008636755], { srs: 4326 }),
size: [width, height]
});
// result is the following object
{
// multi-dimensional numberical arrays separated by source, then band, then row, then column
data: [
[
[
[6453, 7692, 12722, 7274, 6302, 6234, 6147, 6276, ...], // first row of first band
[5997, 9353, 12493, 6389, 10166, 6285, 10634, 7954, ...] // second row of second band
],
[ ... ] // second band
[ ... ] // third band
],
[ [ [...] ... ] ... ] // second georaster
[ [ [...] ... ] ... ] // third georaster
],
size: [ result_data_width, result_data_height ]
}
`$3
#### optional properties
js
const stack = await GeoRasterStack.init({
sources: [...], // optional properties
debug_level: 2,
flat: true, // flatten all the georaster results when reading by one level, so they appear as if they came from the same source
method: "near-vectorize", // resampling method via https://github.com/danieljdufour/geowarp
turbo: true // apply experimential projection turbo charging via https://github.com/DanielJDufour/proj-turbo
});
`$3
If you want to read using pixel coordinates, pass in an extent with srs set to "simple".
Inspired by Leaflet's Simple CRS, "simple" srs is when the bottom left corner of the image is [0, 0]
and the top-right of the image is [image_width, image_height].
js
await stack.read({
extent: new GeoExtent([512, 256, 768, 512], { srs: "simple" }),
size: [512, 512]
});
``