arso-rainfall-intensity

This project is written in typescript 3.9, but you can use its transpiled javascript built which targets ES2015*.
* Built includes typings and declaration map (for debugging), so if your IDE is good enough you'll get module type hints working with JS.

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Documentation by example:

``

javascript

    const fs = require('fs');

    const { ArsoHttpApi, ArsoProjection } = require('arso-rainfall-intensity');

    

    // returns snapshots from oldest to newest (moving window 2 hours span, with sample rate of 5 mins) 

    const latestSnapshots = await ArsoHttpApi.fetchLatestRadarSnapshotsTimeline();

    const mostRecentSnapshot = latestSnapshots[latestSnapshots.length - 1];

    console.log('snapshot time:', mostRecentSnapshot.dateTime);

    // fetch the radar image

    const radarImageBuffer = await mostRecentSnapshot.fetchRadarImageBuffer();

    // for debug view we can save it on disk

    fs.writeFileSync('latest.png', radarImageBuffer);



    const projection = new ArsoProjection();

    // initialize the projection from buffer, striping all unknown pixel colors seen in image.

    // developer must ensure that the image buffer is from the arso api (if he's not using the given api wrapper in this module).

    projection.loadImageFromBuffer(radarImageBuffer);



    // loadImageFromBuffer strips all unknown pixels and sets them to 0,0,0,0 - rgba (For example: removing the red border around the borders of radar image)

    fs.writeFileSync('latest-processed.png', projection.getImageBuffer());



    // returns rgba pixel values at given location in picture 

    // Note 0,0 is top left of the picture.

    projection.getPixelInfo({ x: 69, y: 69 });



    // returns result object that inteprets pixel values 

    // * result.value = integer value of dBZ (range of 0 - 57) - decibel relative to Z https://en.wikipedia.org/wiki/DBZ_(meteorology)

    // * result.group = integer range of 0 - 4, gruping by near values of .value [0 dBZ = 0, 15-24 dBZ = 1, 27-36 dBZ = 2, 39-48 dBZ = 3,  51-57 dBZ = 4]

    // * result.pixel = rgb value of the pixel (ignoring alpha)

    projection.getPixelRadarValue({ x: 69, y: 69 });



    // because radar image is bad at the bounds (preprocessing is removing all pixels outside)

    // you can check if point is inside the boundings.

    projection.isPixelInInterestBounds({ x: 69, y: 69 });

    // instead of using the above method, bounds can be accessed from the following property.

    projection.interestPixelBounds



    // Given lng lat, returns the pixel position in radar image.

    projection.projectDegreeUnitToImagePixel({ x: LNG_VALUE, y: LAT_VALUE });



    // Given lng lat, returns meter position

    projection.projectDegrees2MeterUnits({ x: LNG_VALUE, y: LAT_VALUE });



    // Given pixel location, returns the lng lat postion

    projection.projectImagePixelToDegreeUnit({ x: 69, y: 69 });



    // Given pixel location, returns the meter postion

    projection.projectImagePixelToMeterUnit({ x: 69, y: 69 });



    // Given meter location, returns the pixel position

    projection.projectMeterUnitToImagePixel({ x: METER_LNG_VALUE, y: METER_LAT_VALUE });



    // Given meter locatiom, returns the lng lat position

    projection.projectMetersToDegreeUnits({ x: METER_LNG_VALUE, y: METER_LAT_VALUE });

This project is written in

, but you can use its transpiled javascript built which targets

javascript
const fs = require('fs');
const { ArsoHttpApi, ArsoProjection } = require('arso-rainfall-intensity');

// returns snapshots from oldest to newest (moving window 2 hours span, with sample rate of 5 mins)
const latestSnapshots = await ArsoHttpApi.fetchLatestRadarSnapshotsTimeline();
const mostRecentSnapshot = latestSnapshots[latestSnapshots.length - 1];
console.log('snapshot time:', mostRecentSnapshot.dateTime);
// fetch the radar image
const radarImageBuffer = await mostRecentSnapshot.fetchRadarImageBuffer();
// for debug view we can save it on disk
fs.writeFileSync('latest.png', radarImageBuffer);

const projection = new ArsoProjection();
// initialize the projection from buffer, striping all unknown pixel colors seen in image.
// developer must ensure that the image buffer is from the arso api (if he's not using the given api wrapper in this module).
projection.loadImageFromBuffer(radarImageBuffer);

// loadImageFromBuffer strips all unknown pixels and sets them to 0,0,0,0 - rgba (For example: removing the red border around the borders of radar image)
fs.writeFileSync('latest-processed.png', projection.getImageBuffer());

// returns rgba pixel values at given location in picture
// Note 0,0 is top left of the picture.
projection.getPixelInfo({ x: 69, y: 69 });

// returns result object that inteprets pixel values
// * result.value = integer value of dBZ (range of 0 - 57) - decibel relative to Z https://en.wikipedia.org/wiki/DBZ_(meteorology)
// * result.group = integer range of 0 - 4, gruping by near values of .value [0 dBZ = 0, 15-24 dBZ = 1, 27-36 dBZ = 2, 39-48 dBZ = 3, 51-57 dBZ = 4]
// * result.pixel = rgb value of the pixel (ignoring alpha)
projection.getPixelRadarValue({ x: 69, y: 69 });

// because radar image is bad at the bounds (preprocessing is removing all pixels outside)
// you can check if point is inside the boundings.
projection.isPixelInInterestBounds({ x: 69, y: 69 });
// instead of using the above method, bounds can be accessed from the following property.
projection.interestPixelBounds

// Given lng lat, returns the pixel position in radar image.
projection.projectDegreeUnitToImagePixel({ x: LNG_VALUE, y: LAT_VALUE });

// Given lng lat, returns meter position
projection.projectDegrees2MeterUnits({ x: LNG_VALUE, y: LAT_VALUE });

// Given pixel location, returns the lng lat postion
projection.projectImagePixelToDegreeUnit({ x: 69, y: 69 });

// Given pixel location, returns the meter postion
projection.projectImagePixelToMeterUnit({ x: 69, y: 69 });

// Given meter location, returns the pixel position
projection.projectMeterUnitToImagePixel({ x: METER_LNG_VALUE, y: METER_LAT_VALUE });

// Given meter locatiom, returns the lng lat position
projection.projectMetersToDegreeUnits({ x: METER_LNG_VALUE, y: METER_LAT_VALUE });