Landsat NDVI batch calculation

Question

I want to perform a time series analysis of Landsat NDVI. I could not find a prepared product online (except in GE Engine but it is no possible to download). Thus I would like to calculate the NDVI in batch, possibly applying a rule to keep the filename (I need the reference of the date).

Answer 1

I have a code for IDL/ENVI to do it:

; reading multiband image, calculate NDVI and save them in a file


pro CalculateNDVI

  ; error handling

  compile_opt IDL2

  Catch, theError

  IF theError NE 0 THEN BEGIN

    Catch, /Cancel

    MESSAGE, /REISSUE_LAST

    stop

  ENDIF


  ; count number of input files from the specified folders

  file_name = file_search('D:\mmrahm\Rangeland_Monitoring_Aug14Feb15\Works\Site1\MODIS_Site1\*.tif', COUNT = Nfiles)

 print, 'Number of files to be processed = ', Nfiles


  ; read files one by one and downscale it using MODIS data

  for ifile = 0, Nfiles-1 do begin
    print, 'Current File: ', file_name[ifile]

    ; read current UAV file and header informations
    Data = read_tiff(file_name[ifile])
    result = query_tiff(file_name[ifile], info, GEOTIFF = geo)

    imagesize = info.dimensions
    W = imagesize[0]
    H = imagesize[1]
    C = (size(Data))[1]
    print, 'Width = ', W
    print, 'Height = ', H
    print, 'Number of Channels = ', C

    ;create empty output channel
    NDVI = intarr(W, H)
    ; calculate NDVI
    NDVI = (float(Data[3,*,*])-Data[2,*,*])/(float(Data[3,*,*])+Data[2,*,*])

    ;create output file name from input file
    OutFileName = strmid(file_name[ifile], 70,30)+'_NDVI'

    print, 'output_file_name = ', OutFileName
    ; write data to
    write_tiff, 'D:\mmrahm\Rangeland_Monitoring_Aug14-Feb15\Test1\'+OutFileName+'.tif', NDVI, /float, geotiff = geo

  endfor


end