I have a 2GB .tif file. It is 16 bit, and I know the values range from 0 to 2047 (i.e., 11 bits are used in the values). It reports three bands, RGB, and when I use poBand->ComputeStatistics() on each band I get:
red band (first): min: 0, max: 1953 green band (second): min: 0, max: 2047 blue band (third): min: 0, max: 1991 But when I open the same file in ArcMap, get the Layer Properties, look at the Symbology tab, set the stretch type to Minimum-Maximum, uncheck Apply Gamma Stretch, and click the Histograms button, it shows the following values: Red: min: 60, max: 1547 Green: min: 230, max: 2047 Blue: min: 208, max: 1326 It is behaving as if (perhaps) ArcMap is throwing out a certain percentage of outlier low and high values when reporting the statistics. But I have Minimum-Maximum set as the stretch type, not Percentage Clip, and in any event, my understanding is that the chosen stretch type should not affect the statistics shown on the Histograms dialog box; that those values are the raw values in the file. Do you have any idea why GDAL would be reporting different min/max values for the bands? Any ideas on how I can debug it?
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