🚀 go-pugleaf

I have a program by a researcher no longer here.  It is in
not particularly structured FORTRAN IV written for a PDP 11/60.
The task it performed successfully on that machine was to mean
filter an image, but it sensed whether there was an edge in the
region it was looking at, and if so it preserved it.  Thus 
"noise" was removed without blurring the image appreciably.

I would like to translate it into C and use it on images of a
different size and depth from which it was written, and on a 
different make of framestore and on a Sun.  So it is almost a
complete rewrite that is required.  

So:  Can anyone help me chase up the reference taken from the
header of the program, please?  I am sure I have seen the paper,
and that I did not understand it the first time, and I would
like to read it again.  However I cannot find any clues to where
it might be.  

If someone can point me to another algorithm that does much the
same thing that would be equally good.  OR if someone can find me
a cheap Fortran to C de-spaghettifier & translater I would very
grateful, as just translating it automatically with the tool I 
used preserved the gotos !!! 
The program header, with spelling preserved! follows:

        PROGRAM AAP
C
C       THIS PROGRAM IS USING ADAPTIVE AVERAGE PROCESSOR TO
C       SMOOTH THE NOISE AND PRESERVE THE EDIGES
C
C       THE ALGORITHM IS FROM FUMIAKI et al. 107/smac feb. 1977
C
C       Y.YOU
C

Thank you,
	Hugh
+--------------------------------------------------------------+
+          Hugh Sasse                                          +
+                                                              +
+   Post:  Computer Systems Electronic Engineer                +
+          Dept. of Electrical and Electronic Engineering,     +
+          De Montfort University,                             +
+          The Gateway,                                        +
+          LEICESTER                                           +
+          ENGLAND   LE1 9BH                                   +
+                                                              +
+   Phone: +44 533 551551 x8065                                +
+   Fax:   +44 533 577052                                      +
+                                                              +
+   Email: hgs@uk.ac.dmu                          (JANET)      +
+          hgs%uk.ac.dmu@ukacrl                   (BITNET)     +
+          hgs%uk.ac.dmu@nsfnet-relay.ac.uk       (ARPA)       +
+--------------------------------------------------------------+