Here is an example of one of these map sets.  This is the original as it was
sent to me, but I would crop each map individually.

https://docs.google.com/viewer?a=v&pid=explorer&chrome=true&srcid=0B0d3zfSSPFQsY2MxODEyZWEtZTRkZC00OTk2LTgwY2YtYTZkYzcwZGYxZDll&hl=en&authkey=CLmWvWc

<https://docs.google.com/viewer?a=v&pid=explorer&chrome=true&srcid=0B0d3zfSSPFQsY2MxODEyZWEtZTRkZC00OTk2LTgwY2YtYTZkYzcwZGYxZDll&hl=en&authkey=CLmWvWc>In
my original post I asked about classifying squares and triangle for the sake
of simplicity, but as you can see the symbols used for this (published in
the 1970s) aren't that easy to distinguish.  Luckily, I don't think there is
too much background noise, but maybe the 10 x10 grid lines will be
problematic?

Since this was scanned from the pages of a bound book, a curvature was
induced in the scanned copy too, so the borders aren't perfectly square.  We
might be able to resolve this by scanning things more carefully, but your
thoughts on this are very welcome too.

Thanks,

Tim

On Fri, Mar 18, 2011 at 2:04 PM, Barry Rowlingson <
b.rowlingson@lancaster.ac.uk> wrote:

> On Fri, Mar 18, 2011 at 9:44 PM, tsippel <tsippel@gmail.com> wrote:
> > I have a series of scanned global maps (from a bound Atlas) of
> oceanographic
> > sampling effort that I would like to classify. On 1 x1 lat/lon grids are
> > symbols that represent sampling density.  I need to read in these scanned
> > maps, and classify the symbols (squares are classified as 1, triangles as
> 2,
> > etc.) and hopefully store them in raster grid files (.asc) for analysis.
> >
> > After some trawling through CRAN looking for packages for this, it is not
> > yet apparent to me which is best.  I've considered using a GIS for this
> (ie.
> > GRASS), but I'm not sure if that is a more complicated solution to a
> simpler
> > problem.  I need to process a directory of these images, so scripting the
> > process to loop over the directory would be ideal.
>
>  So you've got some high resolution page images and want to do
> recognition of the shapes in the grid cells?
>
>  Depending on how much noise there is it might be easy or difficult...
> Any chance you can get us a sample image, or a section of one? How
> many different symbols are there, and how big is the grid? I guess
> global means 360x180, but what's the image resolution? Is there also a
> map outline background to confuse things? MIght be easier to attack
> this with an image processing toolbox like imageJ...
>
> Barry
>

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