r - 如何在 R 中堆叠具有几乎完全相同范围的栅格

Question

我正在尝试堆叠多波段栅格。它们是通过 ESA Sentinel 1 预处理工具 SNAP 创建的。每个 tif 文件都必须分层。

我加载了两个光栅堆栈并尝试堆叠它们:

rs1 <- raster::stack("example/rs1.tif")
rs2 <- raster::stack("example/rs2.tif")
rsstack <- stack(rs1,rs2)

然后我收到以下错误消息:

Error in compareRaster(x) : different extent

光栅堆栈的范围几乎相同:

> rs1
class      : RasterBrick 
dimensions : 2273, 2100, 4773300, 2  (nrow, ncol, ncell, nlayers)
resolution : 8.983153e-05, 8.983153e-05  (x, y)
extent     : 8.183134, 8.37178, 48.49076, 48.69495  (xmin, xmax, ymin, ymax)
crs        : +proj=longlat +datum=WGS84 +no_defs 
source     : memory
names      : S1A_IW_GRDH_1SDV_20180110T053421_20180110T053446_020088_0223E7_69E7_10.1, S1A_IW_GRDH_1SDV_20180110T053421_20180110T053446_020088_0223E7_69E7_10.2 
min values :                                                             1.729380e-07,                                                             1.077101e-06 
max values :                                                                 11.63158,                                                                109.76797 

> rs2
class      : RasterBrick 
dimensions : 2273, 2100, 4773300, 2  (nrow, ncol, ncell, nlayers)
resolution : 8.983153e-05, 8.983153e-05  (x, y)
extent     : 8.183171, 8.371817, 48.49071, 48.6949  (xmin, xmax, ymin, ymax)
crs        : +proj=longlat +datum=WGS84 +no_defs 
source     : memory
names      : S1A_IW_GRDH_1SDV_20180106T171534_20180106T171559_020037_02223E_CE2A_10.1, S1A_IW_GRDH_1SDV_20180106T171534_20180106T171559_020037_02223E_CE2A_10.2 
min values :                                                             8.244981e-08,                                                             5.691331e-06 
max values :                                                                 6.012002,                                                                64.965996 

我该怎么做才能将两者堆叠在一起？如何调整对方的范围？

我尝试过的: 我也有一个感兴趣的领域。所以我尝试将两个堆栈裁剪到感兴趣的区域，并尝试再次堆叠它们:

shp <- readOGR(dsn=path.expand(example/area.shp)))
shp <- sp::spTransform(shp, CRS(proj4string(rs[[1]]))) 
rs1 <- raster::crop(rs1,shp)
rs2 <- raster::crop(rs2,shp)
rsstack <- stack(rsstack,r2)

Error in compareRaster(x) : different extent

shp
class       : SpatialPolygonsDataFrame 
features    : 16 
extent      : 8.183144, 8.371817, 48.49075, 48.69491  (xmin, xmax, ymin, ymax)
crs         : +proj=longlat +datum=WGS84 +no_defs 
variables   : 14
names       : fid,           Area,    BoundLen,         CentX,         CentY,       AreaIncI,  BoundNotIn,    CentXNotIn,    CentYNotIn,    PointInPol,    PointInPo1, CompactRat, CompactRa1, rast 
min values  :   1,     1440.64063,   168.67161, 3442255.57469, 5377418.66407,     1440.64063,   168.67161, 3442255.57469, 5377418.66407, 3442259.72286,  5377409.4208,    1.14669,    1.14669,    1 
max values  :  16, 76089100.06641, 89693.52095, 3451427.74745, 5393682.39749, 76858585.26953, 76662.07157, 3451427.74745, 5393682.39749, 3451416.96957, 5393687.75063,    2.57399,    2.90065,    1

有人有解决办法吗？

Answer 1

我可以看到您的栅格具有相同的坐标系(crs:+proj=longlat +datum=WGS84 +no_defs)，只是范围不同。首先，您可以裁剪它，然后可以使用 raster 包中的 resample 函数，例如

library(raster)

#Crop the raster
rs1 <- raster::crop(rs1,shp)
rs2 <- raster::crop(rs2,shp)

#Conversion of rasters into same extent
rs2_resampled <- resample(rs2, rs1, method='bilinear')

#Stack the rasters
rsstack <- stack(rs1,rs2_resampled)