[gdal-dev] Re: [GDAL_TRANSLATE] Gray scale

[Solimyr]

I already tried this step:

$ gdal_translate -of ENVI -ot Byte -scale  File.tif Prova.raw
Input file size is 1828, 1646
0...10...20...30...40...50...60...70...80...90...100 - done.

$ gdalinfo -stats prova.raw
Driver: ENVI/ENVI .hdr Labelled
Files: prova.raw
       prova.raw.aux.xml
       prova.hdr
Size is 1828, 1646
Coordinate System is:
PROJCS["UTM Zone 47, Southern Hemisphere",
    GEOGCS["WGS 84",
        DATUM["WGS_1984",
            SPHEROID["WGS 84",6378137,298.257223563,
                AUTHORITY["EPSG","7030"]],
            TOWGS84[0,0,0,0,0,0,0],
            AUTHORITY["EPSG","6326"]],
        PRIMEM["Greenwich",0,
            AUTHORITY["EPSG","8901"]],
        UNIT["degree",0.0174532925199433,
            AUTHORITY["EPSG","9108"]],
        AUTHORITY["EPSG","4326"]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",0],
    PARAMETER["central_meridian",99],
    PARAMETER["scale_factor",0.9996],
    PARAMETER["false_easting",500000],
    PARAMETER["false_northing",10000000],
    UNIT["Meter",1]]
Origin = (650301.875000000000000,9895384.375000000000000)
Pixel Size = (1.250000000000000,-1.250000000000000)
Metadata:
  Band_1=Band 1
  TIFFTAG_XRESOLUTION=1
  TIFFTAG_YRESOLUTION=1
  AREA_OR_POINT=Area
Image Structure Metadata:
  INTERLEAVE=BAND
Corner Coordinates:
Upper Left  (  650301.875, 9895384.375) (100d21' 2.82"E,  0d56'46.41"S)
Lower Left  (  650301.875, 9893326.875) (100d21' 2.84"E,  0d57'53.40"S)
Upper Right (  652586.875, 9895384.375) (100d22'16.73"E,  0d56'46.38"S)
Lower Right (  652586.875, 9893326.875) (100d22'16.76"E,  0d57'53.37"S)
Center      (  651444.375, 9894355.625) (100d21'39.79"E,  0d57'19.89"S)
Band 1 Block=1828x1 Type=Byte, ColorInterp=Undefined
  Description = Band 1
  Minimum=0.000, Maximum=255.000, Mean=2.364, StdDev=3.013
  Metadata:
    STATISTICS_MINIMUM=0
    STATISTICS_MAXIMUM=255
    STATISTICS_MEAN=2.3638978918458
    STATISTICS_STDDEV=3.0127939567847

And the results from ENVI is:

$ gdalinfo -stats fromENVI.raw
Driver: ENVI/ENVI .hdr Labelled
Files: fromENVI.raw
       fromENVI.raw.hdr
Size is 1828, 1646
Coordinate System is:
PROJCS["UTM Zone 47, Southern Hemisphere",
    GEOGCS["WGS 84",
        DATUM["WGS_1984",
            SPHEROID["WGS 84",6378137,298.257223563,
                AUTHORITY["EPSG","7030"]],
            TOWGS84[0,0,0,0,0,0,0],
            AUTHORITY["EPSG","6326"]],
        PRIMEM["Greenwich",0,
            AUTHORITY["EPSG","8901"]],
        UNIT["degree",0.0174532925199433,
            AUTHORITY["EPSG","9108"]],
        AUTHORITY["EPSG","4326"]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",0],
    PARAMETER["central_meridian",99],
    PARAMETER["scale_factor",0.9996],
    PARAMETER["false_easting",500000],
    PARAMETER["false_northing",10000000],
    UNIT["Meter",1]]
Origin = (650301.875000000000000,9895384.375000000000000)
Pixel Size = (1.250000000000000,-1.250000000000000)
Metadata:
  Band_1=Gray Scale (Band 1:File.tif)
Image Structure Metadata:
  INTERLEAVE=BAND
Corner Coordinates:
Upper Left  (  650301.875, 9895384.375) (100d21' 2.82"E,  0d56'46.41"S)
Lower Left  (  650301.875, 9893326.875) (100d21' 2.84"E,  0d57'53.40"S)
Upper Right (  652586.875, 9895384.375) (100d22'16.73"E,  0d56'46.38"S)
Lower Right (  652586.875, 9893326.875) (100d22'16.76"E,  0d57'53.37"S)
Center      (  651444.375, 9894355.625) (100d21'39.79"E,  0d57'19.89"S)
Band 1 Block=1828x1 Type=Byte, ColorInterp=Undefined
  Description = Gray Scale (Band 1:File.tif)
  Minimum=0.000, Maximum=255.000, Mean=53.375, StdDev=48.454
  Metadata:
    STATISTICS_MINIMUM=0
    STATISTICS_MAXIMUM=255
    STATISTICS_MEAN=53.374992023631
    STATISTICS_STDDEV=48.454042778451

Looking at the histogram seems that ENVI do a conversion using a kind of
equalize scale. Do you know where I can find the method that ENVI use? I
have searched a lot without solution and seems that I'm the only one with
this problem! Very strange!

--
View this message in context: http://osgeo-org.1803224.n2.nabble.com/GDAL-TRANSLATE-Gray-scale-tp6533237p6533558.html
Sent from the GDAL - Dev mailing list archive at Nabble.com.