[Rd] serialized plot object (for a certain device)

[Prof Brian Ripley]

On Sat, 1 Sep 2007, Tobias Verbeke wrote:

> Dear list,
>
> Using serialize it is possible to save
> the binary string representing an R
> object to a raw R vector.
>
> ## adapted from ?serialize
> x <- serialize(list(1,2,3), NULL)
> x
>
> I am looking for a way to capture
> the binary string that in normal
> use of graphics devices will be
> written to (most commonly) a file
> connection.

Nope, unfortunately, they write to files not connections and no R object 
is involved.

> jpeg(file = "test.jpg")
>   plot(1:10)
> dev.off()
>
> In other words, is there a way of
> capturing the binary `jpeg string'
> representing the plot(1:10) graph,
> e.g. into a raw vector ?

Only by rewriting the jpeg library used to write the file.  In the case of 
jpeg it is done here:

   /* Step 2: specify data destination (eg, a file) */
   jpeg_stdio_dest(&cinfo, outfile);


-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
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