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Extract multiple raster by mask automatically

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09-20-2019 08:23 AM
gianguyen
Emerging Contributor

Hi Community, 
I am working with a project where I have to extract 3650 rasters. It will take forever to get it done manually. 

I am thinking about using ArcPy or Modelbuilder to do it automatically.

Can you help me with this?

Thank you so much

Gia Nguyen

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7 Replies
George_Thompson
Esri Notable Contributor

I would look at this GP tool and you can batch it in Model Builder - Extract by Mask—Help | ArcGIS Desktop or write Python to iterate through and do the process.

--- George T.
PavanYadav
Esri Contributor

Alternatively you can use the Clip Raster—Data Management toolbox | ArcGIS Desktop tool. But it all depends on your need. The Clip Raster tool is bit different from the the Extract by Mask tool. The Clip Raster tool cuts out a portion of a raster dataset (extent changes) while Extract by Mask tool does not change the extent of the raster but converts values outside of the clip feature/raster to NoData.

here is one example:

import arcpy
import os

workspace = r"D:\test\Stowe.gdb"
arcpy.env.workspace = "D:\test\Stowe.gdb"
fc = r'D:\test\Stowe.gdb\clip_feature'

desc = arcpy.Describe(fc)

xmin = desc.extent.XMin
xmax = desc.extent.XMax
ymin = desc.extent.YMin
ymax = desc.extent.YMax

rectangle = str(xmin) +' '+ str(ymin) +' '+ str(xmax) +' '+ str(ymax)

rasters = []

walk = arcpy.da.Walk(workspace, datatype="RasterDataset") #

for dirpath, dirnames, filenames in walk:
    for filename in filenames:
        print(filename)
        rasters.append(os.path.join(dirpath, filename))

for raster in rasters:  
    arcpy.Clip_management(raster, rectangle, raster + "_clip")

Pavan Yadav
Product Engineer at Esri
AI for Imagery
Connect with me on LinkedIn!
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gianguyen
Emerging Contributor

Hi Pavan Yadav,

I appreciate your suggestion. It is very helpful.

I got another issue. I want to convert multiple NetCDF files to rasters

using ArcPy or Python.

Here is the code for a NetCDF file that I learned from ESRI. Can you help

me to edit it to read convert multiple file?

Thanks

  1. Import system modules

import arcpy

  1. Set local variables

inNetCDFFile = "C:/data/netcdf/rainfall.nc"

variable = "pptx"

XDimension = "lon"

YDimension = "lat"

outRasterLayer = "rainfall"

bandDimmension = ""

dimensionValues = ""

valueSelectionMethod = ""

cellRegistration = ""

  1. Execute MakeNetCDFRasterLayer

arcpy.MakeNetCDFRasterLayer_md(inNetCDFFile, variable, XDimension,

YDimension,

outRasterLayer, bandDimmension,

dimensionValues,

valueSelectionMethod, cellRegistration)

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PavanYadav
Esri Contributor

Hi gia nguyen

To filter *.nc files only please try, the following:


ncFiles = []
workspace = r"D:\test"

#datatype limits the results returned. See supported datatypes:
#Walk—Help | ArcGIS for Desktop.


walk = arcpy.da.Walk(workspace)

for dirpath, dirnames, filenames in walk:
    for filename in filenames:

#NC is not a supported datatype so filtering like this: "if filename[-3:]=='.nc'"
        if filename[-3:]=='.nc':
            ncFiles.append(os.path.join(dirpath, filename))

Pavan Yadav
Product Engineer at Esri
AI for Imagery
Connect with me on LinkedIn!
Contact Esri Support Services
gianguyen
Emerging Contributor

Hi Louise Thank you for your response. While waiting for the best solution,

I tried the code below. It works still now. I use it to convert from NetCDF

files to rasters.

import arcpy

from arcpy import env

from arcpy.sa import *

Input_Temp_folder = "E:\Mekong\DATA\JMP_Deeplearning_data\Mekong_temp\Temp_2017"

Out_Temp_folder_Max

="E:\Mekong\DATA\JMP_Deeplearning_data\Mekong_temp\Temp_2017\Max"

Out_Temp_folder_Min

="E:\Mekong\DATA\JMP_Deeplearning_data\Mekong_temp\Temp_2017\Min"

arcpy.env.workspace = Input_Temp_folder

arcpy.env.overwriteOutput = True

arcpy.env.scratchWorkspace = Out_Temp_folder_Max # Create scratch workspace

arcpy.env.scratchWorkspace = Out_Temp_folder_Min # create Scratch workspace

variableTemp1 = "T2MMAX"

variableTemp2="T2MMIN"

XDimension = "lon"

YDimension = "lat"

time = "time"

NetCDFfiles = arcpy.ListFiles("*.nc4.nc")

print NetCDFfiles

for filename in NetCDFfiles:

print ("Processing: " + filename)

day = filename[27:35]# extract date in the filenames

outRasterLayer_Temp_Max = variableTemp1 + "_" + day # create a

time series for names

outRasterLayer_Temp_Min = variableTemp2 + "_" + day # create a

time series for names

InNetCDTemp = arcpy.env.workspace + "/" + filename # get a file

arcpy.MakeNetCDFRasterLayer_md(InNetCDTemp, variableTemp1,

XDimension, YDimension, outRasterLayer_Temp_Max,time)

arcpy.MakeNetCDFRasterLayer_md(InNetCDTemp, variableTemp2,

XDimension, YDimension, outRasterLayer_Temp_Min,time)

outRasterTemp_Folder = Out_Temp_folder_Min

arcpy.SplitRaster_management

(outRasterLayer_Temp_Max,Out_Temp_folder_Max,outRasterLayer_Temp_Max,"POLYGON_FEATURES","TIFF","NEAREST","","","","DEGREES","","","Mekong_Basin","","","")

arcpy.SplitRaster_management

(outRasterLayer_Temp_Min,Out_Temp_folder_Min,outRasterLayer_Temp_Min,"POLYGON_FEATURES","TIFF","NEAREST","","","","DEGREES","","","Mekong_Basin","","","")

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gianguyen
Emerging Contributor

Thank you for your suggestions. They are very useful. 

Besides, I also found a tool SAMPLE which can extract value from rasters (single/multi bands) into a grid (fishnet). 

Again, thank you so much

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PavanYadav
Esri Contributor

I'm glad you find it useful.

Regards,

Pavan

Pavan Yadav
Product Engineer at Esri
AI for Imagery
Connect with me on LinkedIn!
Contact Esri Support Services
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