GEE下载Landsat8影像数据

// 1. load landsat 8 data
var image = ee.ImageCollection('LANDSAT/LC08/C01/T1_SR')
.filterDate('2018-01-01','2018-12-31')
.filterBounds(roi)
.sort('CLOUD_COVER')
.first();
// 2. visialization parameter
var vis = {bands:['B4','B3','B2'],min:0,max:3000,gama:1.4};
Map.addLayer(image,vis,"my landsat 8 in 2018");
Map.addLayer(image.clip(roi),vis,'landsat image in my roi');
Map.centerObject(roi,8);
//var myimage = image.clip(roi);
//Map.addLayer(myimage,vis,"myimage");
// 3. to my drive not yours
Export.image.toDrive({
image:image.int16(),
description:"landsat2018",
scale:30,
region:roi,
maxPixels:1e13
});