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Why this raster (tiff) does not have any values?

Why I am unable to perform:

doubleclick -> onechannel pseudocolor -> clafify

Both rasters are downloaded from the same site: www.globalforestwatch.org from their "data page" respectively.

Working (from picture below) http://commondatastorage.googleapis.com/earthenginepartners-hansen/GFC2013/Hansen_GFC2013_lossyear_50N_130W.tif

Not-working (from picture below) http://commondatastorage.googleapis.com/earthenginepartners-hansen/GFC2013/Hansen_GFC2013_lossyear_60N_140W.tif

What is the difference in these tiff's? I am using Qgis 2.2 on Ubuntu.

enter image description here

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  • where are these tiles located ? Tiles with only water are provided for the sake of completeness but without data.
    – radouxju
    Mar 13, 2014 at 19:08
  • I am 100% sure that it is not water. (North-west coast of North America). Black box in right corner down is all land.
    – Ladislav Naďo
    Mar 13, 2014 at 19:11
  • 1
    Indeed, you are right. The tile is OK.I could display it in ArcGIS (it just took a while). Have you tried to download the tile a second time ?
    – radouxju
    Mar 13, 2014 at 19:48
  • I tried to download it multiple times, from various computers, "HaveYouTriedToTurnItOffAndOnAgain" method...(Maybe some bug in QGis [2.2 version is quite new])..thank you for your help, I try ArcGis
    – Ladislav Naďo
    Mar 13, 2014 at 19:50

1 Answer 1

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I get a similar result when I load these tiffs into QGIS 2.2.0, with the 60N tif showing max and min values of 0.

Using the gdalinfo -stats option on these tifs suggests that both do have some values:

E:\TESTing>gdalinfo -stats Hansen_GFC2013_lossyear_60N_140W.tif
Driver: GTiff/GeoTIFF
Files: Hansen_GFC2013_lossyear_60N_140W.tif
       Hansen_GFC2013_lossyear_60N_140W.tif.aux.xml
Size is 36001, 36001
Coordinate System is:
GEOGCS["WGS 84",
    DATUM["WGS_1984",
        SPHEROID["WGS 84",6378137,298.257223563,
            AUTHORITY["EPSG","7030"]],
        AUTHORITY["EPSG","6326"]],
    PRIMEM["Greenwich",0],
    UNIT["degree",0.0174532925199433],
    AUTHORITY["EPSG","4326"]]
Origin = (-140.000138888888900,60.000138888888884)
Pixel Size = (0.000277777777778,-0.000277777777778)
Metadata:
  AREA_OR_POINT=Area
Image Structure Metadata:
  COMPRESSION=LZW
  INTERLEAVE=BAND
Corner Coordinates:
Upper Left  (-140.0001389,  60.0001389) (140d 0' 0.50"W, 60d 0' 0.50"N)
Lower Left  (-140.0001389,  49.9998611) (140d 0' 0.50"W, 49d59'59.50"N)
Upper Right (-129.9998611,  60.0001389) (129d59'59.50"W, 60d 0' 0.50"N)
Lower Right (-129.9998611,  49.9998611) (129d59'59.50"W, 49d59'59.50"N)
Center      (-135.0000000,  55.0000000) (135d 0' 0.00"W, 55d 0' 0.00"N)
Band 1 Block=36001x1 Type=Byte, ColorInterp=Gray
  Minimum=0.000, Maximum=12.000, Mean=0.010, StdDev=0.289
  Metadata:
    STATISTICS_MAXIMUM=12
    STATISTICS_MEAN=0.010206085765138
    STATISTICS_MINIMUM=0
    STATISTICS_STDDEV=0.2891400781453

and

E:\TESTing>gdalinfo -stats Hansen_GFC2013_lossyear_50N_130W.tif
Driver: GTiff/GeoTIFF
Files: Hansen_GFC2013_lossyear_50N_130W.tif
       Hansen_GFC2013_lossyear_50N_130W.tif.aux.xml
Size is 36001, 36001
Coordinate System is:
GEOGCS["WGS 84",
    DATUM["WGS_1984",
        SPHEROID["WGS 84",6378137,298.257223563,
            AUTHORITY["EPSG","7030"]],
        AUTHORITY["EPSG","6326"]],
    PRIMEM["Greenwich",0],
    UNIT["degree",0.0174532925199433],
    AUTHORITY["EPSG","4326"]]
Origin = (-130.000138888888900,50.000138888888884)
Pixel Size = (0.000277777777778,-0.000277777777778)
Metadata:
  AREA_OR_POINT=Area
Image Structure Metadata:
  COMPRESSION=LZW
  INTERLEAVE=BAND
Corner Coordinates:
Upper Left  (-130.0001389,  50.0001389) (130d 0' 0.50"W, 50d 0' 0.50"N)
Lower Left  (-130.0001389,  39.9998611) (130d 0' 0.50"W, 39d59'59.50"N)
Upper Right (-119.9998611,  50.0001389) (119d59'59.50"W, 50d 0' 0.50"N)
Lower Right (-119.9998611,  39.9998611) (119d59'59.50"W, 39d59'59.50"N)
Center      (-125.0000000,  45.0000000) (125d 0' 0.00"W, 45d 0' 0.00"N)
Band 1 Block=36001x1 Type=Byte, ColorInterp=Gray
  Minimum=0.000, Maximum=12.000, Mean=0.172, StdDev=1.156
  Metadata:
    STATISTICS_MAXIMUM=12
    STATISTICS_MEAN=0.17243908812748
    STATISTICS_MINIMUM=0
    STATISTICS_STDDEV=1.1560779557139

When I change the max value to a positive value and reclassify I get a comparable result. I'm not sure if this is some issue with QGIS not reading the tiff metadata correctly, or whether there is some issue with the tif itself.

comparison of tifs in QGIS 2.2.0

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