Figure 3

SubfileType
   Tag = 255 (FF)             Type = short          N = 1
   Indicates the kind of data in the subfile.
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ImageWidth
   Tag = 256 (100)            Type = short          N = 1
   The width (x or horizontal) of the image in pixels.
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ImageLength
   Tag = 257 (101)            Type = short          N = 1
   The length (y or height or vertical) of the image in pixels.
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RowsPerStrip
   Tag = 278 (116)            Type = long           N = 1
   The number of rows per strip. The default is the entire image in one strip.
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StripOffsets
   Tag = 273 (111)            Type = short or long  N = strips per image
   The byte offset for each strip.
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StripByteCounts
   Tag = 279 (117)            Type = long           N = 1
   The number of bytes in each strip.
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SamplesPerPixel
   Tag = 277 (115)            Type = short          N = 1
   The number of samples per pixel (1 for monochrome data, 3 for color).
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BitsPerSample
   Tag = 258 (102)            Type = short          N = SamplesPerPixel
   The number of bits per pixel. 2**BitsPerSample = # of gray levels.
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