raster->vector

import rasterio as rio
from rasterio import features
from rasterio.rio.helpers import coords, write_features
import numpy as np
import json
from shapely.geometry import asShape
from shapely.geometry import mapping


def generate_jsons():
    features = []
    with rio.open("data/esa-cr.tiff", "r") as inputdataset:
        data = inputdataset.read()[0]
        msk = inputdataset.read_masks(1)
        msk = inputdataset.read()[0]
        transform = inputdataset.transform

        msk[msk < 40] = 0
        msk[msk == 40] = 1
        msk[msk > 40] = 0

        kwargs = {
            "transform": transform,
            "mask": msk
        }


        for i, (g, val) in enumerate(
               rio.features.shapes(data, **kwargs)):

            xs, ys = zip(*coords(g))


            geom = asShape(g)
            geom = geom.simplify(30)
            g = mapping(geom)

            features.append({
                'type': 'Feature',
                'id': "{0}".format(i),
                'properties': {
                    'val': val
                },
                'bbox': [min(xs), min(ys), max(xs), max(ys)],
                'geometry': g
            })
    return features


print(json.dumps({
    "type": "FeatureCollection",
    "features": generate_jsons()
    }))