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I have 2m impervious/non-impervious data. I would like to reduce the resolution to 30m and have the cell value for the 30m data be determined by the ratio or proportion of impervious / non-impervious 2m cells that will fall within the 30m block.

I am using ArcGIS 10.2.1 The diagram in red is what I am trying to achieve . I= impervious N=Non-impervious

Below is a graphic representing what I am  trying to do

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    What version of ArcGIS are you using? Would also be helpful if you provided additional context or examples.
    – GISHuman
    Commented Mar 3, 2015 at 21:08
  • Once you replace all "I"s by the value 1 and all "N"s by the value 0 (which is straightforward to do simply by equating the raster to "I"), the new cell values are merely the block means. These two operations are possible in ArcGIS only when you have the Spatial Analyst extension: is that available to you?
    – whuber
    Commented Mar 4, 2015 at 22:35
  • your illustrations shows 3*2 blocks. Is it on purpose ? Indeed , when you resample, you will usually expect square pixels.
    – radouxju
    Commented Mar 5, 2015 at 6:48
  • @radouxju - thank you for asking. Yes , 3*2 was done intentionally - I know in my original question I mentioned I wanted to go from 2m to 30 m; with the picture I was attempting to quickly illustrate what I was asking.
    – MDH
    Commented Mar 7, 2015 at 17:25

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What you need is a software that can resample with an average resampling method. If your input data is binary (0/1) then the output of the average resampling metho will be equivalent to the proportion of "ones". For instance,

gdalwarp -tr 30 30 -r average input.tif output.tif

From what I know, this is not directly possible with ArcGIS. You will need to use focal statistics to compute the average around in a 15 by 15 neighbourhood, then resample at 30 meter with a nearest neighbour resampling method.

EDIT: As @whuber mention, you could also use block statistics. However, you should then make sure that your resampled raster is aligned with your blocks, otherwise there will be a shift in the output values.

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