javascript - Python GEE 从 Landsat 图像中提取特征收集时间序列

Question

我有一个特征集合，我需要从 Landsat 图像中提取 NDWI 的时间序列。

这是我用来提取时间序列的 javascript 功能代码：https ://code.earthengine.google.com/5992f0f029b10a1c57c8ed34e73a368f

现在我试图在 python 中复制相同的脚本，但它在包含 image.mask().and(cloud01.not()) 的行中显示语法错误。我想知道如何在 python 中指定相同的条件。

任何有关它的帮助将不胜感激。

提前致谢。

我的python代码如下：

import datetime
import ee
ee.Initialize()


table = ee.FeatureCollection("users/nbiswas/Buffered_reservoirs_seasia")
L8 = ee.ImageCollection("LANDSAT/LC08/C01/T2"),
table2 = ee.FeatureCollection("users/nbiswas/Madushan"),
table3 = ee.FeatureCollection("users/nbiswas/india_reservoirs_buffer_3km");

class ReservoirExtent():
    def __init__(self):
        self.table = table2
        self.geometry = table2.geometry();
        self.Date_Start = ee.Date('2008-01-01');
        self.Date_End = ee.Date('2018-07-31');
        self.cloud_thresh = 20;

    def clipimage(self, img):
        return img.clip(self.geometry);

    def cloudfunction(self, image):
        #use add the cloud likelihood band to the image
        CloudScore = ee.Algorithms.Landsat.simpleCloudScore(image);
        #isolate the cloud likelihood band
        quality = CloudScore.select('cloud');
        #get pixels above the threshold
        cloud01 = quality.gt(self.cloud_thresh);
        #create a mask from high likelihood pixels
        cloudmask = image.mask().and(cloud01.not());
        #mask those pixels from the image
        return image.updateMask(cloudmask);

    def l8Ndwi(self, img):
        ndwi = img.normalizedDifference(['B3', 'B5']).rename('NDWI');
        return img.addBands(ndwi);

    def areadate(self, img):
            area = img.gt(0).multiply(ee.Image.pixelArea()).divide(1000000).reduceRegion(ee.Reducer.sum(), self.geometry, 30).get('NDWI');
            return img.set('area', area).set('date', img.get('system:time_start'));

    def extentseries(self, reservoir):
        l8images = L8.filterDate(self.Date_Start,self.Date_End).filterBounds(self.geometry);
        print(l8images);
        l8images = l8images.map(self.clipimages);
        l8images = l8images.map(self.cloudfunction);
        l8images = l8images.select(["B3","B5"]);


        # calculate ndwi for each image in imagecollection
        l8ndwi = l8images.map(self.l8Ndwi);
        mosaics = l8ndwi.map(self.areadate)
        mosaics = ee.ImageCollection(mosaics);
        mosaic = mosaics.sort('system:time_start', false);
        list = mosaic.reduceColumns(ee.Reducer.toList(2), ['date', 'area']).get('list');
        print(list);
        #return reservoir.set(ee.Dictionary(ee.List(list).flatten()));


if __name__ == '__main__':
    forecast = ReservoirExtent()
    ppp = forecast.extentseries(table2);
    print(ppp.getInfo());

标签： javascriptpythongoogle-earth-enginelandsat

Answer 1

尝试And代替and：

image.mask().And(cloud01.not())

and这是将 Python运算符与And来自 Google 地球引擎的函数区分开来的少量语法更改。

希望有帮助！