Question

Written raster cell values different to inspector

  • 15 February 2016
  • 3 replies
  • 1 view

Hello,

I'm experiencing some issues with the raster outputs of my workbench. I have the same issue in FME 2016.0.0.0 and 2015.1.2.0.

I am converting several vector files to raster and I am then adding them together to perform some analysis. However, in the output raster negative values, including the No Data value, have been written as the cell value 3.

I have sent the output to a data inspector before the writing stage and the values are correct. I have attached some images below to show the differences

Values from pre-writer stage:

Values from output:

Does anybody have any ideas on how to get the values to write correctly?

I noticed that the output is a 2 bit image and I used a RasterInterpretationCoercer to set it to an 8 bit integer but it still created this 2 bit image with incorrect values.

Thanks in advance


3 replies

Badge +22

What format is your output data? Is it a format that supports 8-bit signed data?

What format is your output data? Is it a format that supports 8-bit signed data?

I'm writing to a geotiff.

I noticed there is parameter in the writer to set the number of bits per cell.

I set that to 8 but it is still creating a 2 bit output

Badge +22

I'm writing to a geotiff.

I noticed there is parameter in the writer to set the number of bits per cell.

I set that to 8 but it is still creating a 2 bit output

If you leave that blank, it should pickup the bit-depth of the raster.

If that doesn't work try writing the data to FFS instead of geotiff and sharing a sample here.

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