new file mode 100644
--- /dev/null
+++ b/imread.m
@@ -0,0 +1,316 @@
+#IMREAD: read images into octave from various file formats
+#
+# Note: this requires the ImageMagick "convert" utility
+#       get this from www.imagemagick.org if required
+#       additional documentation of options is available from the
+#       convert man page
+#
+# BASIC USAGE:
+# img    = imread( fname )
+#                 - img is a greyscale (0-255) of image in fname
+# [im,map]=imread( fname )
+#                 - map is a matrix of [r,g,b], 0-1 triples
+#                 - img is a matrix on indeces into map
+# [r,g,b]= imread( fname )
+#                 - r,g,b are red,green,blue (0-255) compondents
+#
+# Formats for image fname
+#   1. simple guess from extention ie "fig.jpg", "blah.gif"
+#   2. specify explicitly             "jpg:fig.jpg", "gif:blah.gif"
+#   3. specify subimage for multi-image format "tiff:file.tif[3]"
+#   4. raw images (row major format) specify geometry
+#                                      "raw:img[256x180]"
+#
+# IMREAD OPTIONS:
+# imread will support most of the options for convert.1
+#
+# img    = imread( fname , options)
+# [r,g,b]= imread( fname , options)
+#
+# where options is a string matrix (or list) of options
+#
+# example:   options= ["-rotate 25";
+#                      "-crop 200x200+150+150";
+#                      "-sample 200%" ];
+#   will rotate, crop, and then expand the image.
+#   note that the order of operations is important
+#
+# The following options are supported
+#  -antialias           remove pixel-aliasing
+#  -blur geometry       blur the image
+#  -border geometry     surround image with a border of color
+#  -bordercolor color   border color
+#  -colors value        maximum number of colors in the image
+#  -colorspace type     alternate image colorspace
+#  -contrast            enhance or reduce the image contrast
+#  -crop geometry       preferred size and location of the cropped image
+#  -despeckle           reduce the speckles within an image
+#  -dither              apply Floyd/Steinberg error diffusion to image
+#  -draw string         annotate the image with a graphic primitive
+#  -edge radius         apply a filter to detect edges in the image
+#  -emboss radius       emboss an image
+#  -enhance             apply a digital filter to enhance a noisy image
+#  -equalize            perform histogram equalization to an image
+#  -filter type         use this filter when resizing an image
+#  -flip                flip image in the vertical direction
+#  -flop                flop image in the horizontal direction
+#  -font name           font for rendering text
+#  -frame geometry      surround image with an ornamental border
+#  -fuzz distance       colors within this distance are considered equal
+#  -gamma value         level of gamma correction
+#  -geometry geometry   perferred size or location of the image
+#  -gaussian geometry   gaussian blur an image
+#  -gravity type        vertical and horizontal text placement
+#  -implode amount      implode image pixels about the center
+#  -intent type         Absolute, Perceptual, Relative, or Saturation
+#  -interlace type      None, Line, Plane, or Partition
+#  -level value         adjust the level of image contrast
+#  -map filename        transform image colors to match this set of colors
+#  -median radius       apply a median filter to the image
+#  -modulate value      vary the brightness, saturation, and hue
+#  -monochrome          transform image to black and white
+#  -mosaic              create an mosaic from an image sequence
+#  -negate              replace every pixel with its complementary color
+#  -noise radius        add or reduce noise in an image
+#  -normalize           transform image to span the full range of colors
+#  -paint radius        simulate an oil painting
+#  -raise value         lighten/darken image edges to create a 3-D effect
+#  -region geometry     apply options to a portion of the image
+#  -roll geometry       roll an image vertically or horizontally
+#  -rotate degrees      apply Paeth rotation to the image
+#  -sample geometry     scale image with pixel sampling
+#  -scale geometry      resize image
+#  -scene value         image scene number
+#  -segment values      segment an image
+#  -seed value          pseudo-random number generator seed value
+#  -shade degrees       shade the image using a distant light source
+#  -sharpen geometry    sharpen the image
+#  -shave geometry      shave pixels from the image edges
+#  -shear geometry      slide one edge of the image along the X or Y axis
+#  -size geometry       width and height of image
+#  -solarize threshold  negate all pixels above the threshold level
+#  -spread amount       displace image pixels by a random amount
+#  -swirl degrees       swirl image pixels about the center
+#  -texture filename    name of texture to tile onto the image background
+#  -threshold value     threshold the image
+#  -transparent color   make this color transparent within the image
+#  -treedepth value     depth of the color tree
+#  -type type           image type
+#  -unsharp geometry    sharpen the image
+#  -wave geometry       alter an image along a sine wave
+
+
+
+function [out1,out2,out3]= imread(filename, options );
+
+save_empty_list_elements_ok= empty_list_elements_ok;
+unwind_protect
+empty_list_elements_ok= 1;
+
+if (nargin == 0)
+  usage (["img    =  imread (filename,options)\n", ...
+          "[r,g,b]=  imread (filename,options)\n", ...
+          "[img,map]=imread (filename,options)" ]);
+elseif (! isstr (filename))
+  error ("imread: expecting filename as a string");
+endif
+
+if any(filename==':') || any(filename=='[')
+   # we've using special imagemagick characters, so we don't
+   # do any octave path processing
+   fname= filename;
+else
+   fname= file_in_path(IMAGEPATH,filename);
+   if isempty(fname)
+      error(['imread: file ' filename ' not found']);
+   end
+end
+
+# Put together the options string
+# TODO: add some error checking here
+if nargin==1
+   option_str="";
+else
+   option_str="";
+   if     ( is_list( options ) )
+      for i= 1:length(options)
+         option_str=[option_str," ", nth(options,i) ];
+      end
+   elseif ( isstr( options ) )
+      for i= 1:size(options,1)
+         option_str=[option_str," ", options(i,:) ];
+      end
+   else
+     error ("imread: expecting options as a string");
+   end
+end
+#
+# decode the nargout to output what the user wants
+#
+if     nargout==3;
+    wantgreyscale= 0;
+    wantmap= 0;
+    outputtype="ppm";
+elseif nargout==2;
+    wantgreyscale= 0; wantmap= 1;
+    outputtype="ppm";
+else
+    wantgreyscale= 1; wantmap= 0;
+    outputtype="pgm";
+end
+
+   pname= sprintf("convert %s %s %s:- 2>/dev/null",
+                  option_str, fname, outputtype);
+   fid= popen(pname ,'r');
+#  disp(pname); disp(fid);
+#
+# can we open the pipe?
+# if not 1) The file format is wrong and the conver program has bailed out
+#        2) The apropriate converter program hasn't been installed
+#
+   if fid<0;
+      fclose(fid);
+      error(['could not popen ' pname '. Is imagemagick installed?']);
+   end
+
+# get file type
+   line= fgetl( fid );
+   if     strcmp(line, 'P1');   bpp=1; spp=1; bindata=0;
+   elseif strcmp(line, 'P4');   bpp=1; spp=1; bindata=1;
+   elseif strcmp(line, 'P2');   bpp=8; spp=1; bindata=0;
+   elseif strcmp(line, 'P5');   bpp=8; spp=1; bindata=1;
+   elseif strcmp(line, 'P3');   bpp=8; spp=3; bindata=0;
+   elseif strcmp(line, 'P6');   bpp=8; spp=3; bindata=1;
+   else
+      fclose(fid);
+      error(['Image format error for ' fname ]);
+   end
+
+# ignore comments
+   line= fgetl( fid );
+   while length(line)==0 || line(1)=='#'
+      line= fgetl( fid );
+   end
+
+# get width, height
+   [wid, hig]= sscanf( line, '%d %d', 'C' );
+
+# get max component value
+   if bpp==8
+      max_component= sscanf( fgetl(fid), '%d' );
+   end
+
+   if bindata
+      data= fread(fid);
+      numdata= size(data,1);
+
+      if bpp==1
+         data= rem( floor( (data*ones(1,8)) ./ ...
+                 (ones(length(data),1)*[128 64 32 16 8 4 2 1]) ), 2)';
+      end
+   else
+      numdata= wid*hig*spp;
+      data= zeros( numdata,1 );
+      dptr= 1;
+
+         line= fgetl( fid );
+      while !feof( fid)
+         rdata= sscanf( line ,' %d');
+         nptr= dptr + size(rdata,1);
+         data( dptr:nptr-1 ) = rdata;
+         dptr= nptr;
+         line= fgetl( fid );
+      end # feof
+   end #if bindata
+
+   fclose( fid );
+
+   if spp==1
+      greyimg= reshape( data(:), wid, hig )';
+   elseif spp==3
+      redimg= reshape( data(1:spp:numdata), wid, hig )';
+      grnimg= reshape( data(2:spp:numdata), wid, hig )';
+      bluimg= reshape( data(3:spp:numdata), wid, hig )';
+   else
+      error(sprintf("imread: don't know how to handle pnm with spp=%d",spp));
+   end
+
+
+#   This section outputs the image in the desired output format
+# if the user requested the colour map, the we regenerate it from
+# the image.
+#
+#   Of course, 1) This may result in huge colourmaps
+#              2) The colourmap will not be in the same order as
+#                   in the original file
+
+if wantgreyscale
+
+   if exist('greyimg')
+      out1= greyimg;
+   elseif exist('idximg')
+      greymap= mean(map')';
+      out1= reshape( greymap( idximg ) , size(idximg,1), size(idximg,2) );
+   else
+      out1= ( redimg+grnimg+bluimg ) / 3 ;
+   end
+
+elseif wantmap
+
+   if exist('idximg')
+      out1= idximg;
+      out2= map;
+   elseif exist('greyimg')
+      [simg, sidx] = sort( greyimg(:) );
+      [jnkval, sidx] = sort( sidx );
+
+      dimg= [1; diff(simg)>0 ];
+      cimg= cumsum( dimg );
+      out1= reshape( cimg( sidx ) , hig, wid);
+      out2= ( simg(find( dimg ))*[1,1,1] - 1)/256;
+   else
+#
+# attempt to generate a colourmap for r,g,b images, assume range is 0<v<1000
+# for each value ( This will also be inaccurate for noninteger v )
+# however, we shouldn't be getting any of that from the pnm converters
+#
+      c_range= 1000;
+      [simg, sidx] = sort( round(redimg(:)) + ...
+                  c_range *round(grnimg(:)) + ...
+                c_range^2 *round(bluimg(:)) );
+      [jnkval, sidx] = sort( sidx );
+
+      dimg= [1; diff(simg)>0 ];
+      cimg= cumsum( dimg );
+      out1= reshape( cimg( sidx ) , hig, wid );
+      tmpv= simg(find( dimg )) - (1 + c_range + c_range^2);
+      out2= [ rem(tmpv,c_range), ...
+              rem(floor(tmpv/c_range), c_range), ...
+              floor(tmpv/c_range^2) ]/256;
+   end
+
+
+else
+
+   if exist('greyimg')
+      out1= greyimg;
+      out2= greyimg;
+      out3= greyimg;
+   else
+      out1= redimg;
+      out2= grnimg;
+      out3= bluimg;
+   end
+
+end
+
+unwind_protect_cleanup
+empty_list_elements_ok= save_empty_list_elements_ok;
+end_unwind_protect
+
+#
+# $Log$
+# Revision 1.1  2002/03/11 01:56:47  aadler
+# general image read/write functionality using imagemagick utilities
+#
+#

new file mode 100644
--- /dev/null
+++ b/imwrite.m
@@ -0,0 +1,209 @@
+#IMWRITE: write image from octave to various file formats
+#
+# Note: this requires the ImageMagick "convert" utility.
+#       get this from www.imagemagick.org if required
+#       additional documentation of options is available from the
+#       convert man page
+#
+# BASIC USAGE:
+# imwrite( fname, img )
+#                 - img is a greyscale (0-255) of image in fname
+# imwrite( fname, img, map )
+#                 - map is a matrix of [r,g,b], 0-1 triples
+#                 - img is a matrix on indeces into map
+# imwrite( fname, r,g,b );
+#                 - r,g,b are red,green,blue (0-255) compondents
+#
+# Formats for image fname
+#   1. simple guess from extention ie "fig.jpg", "blah.gif"
+#   2. specify explicitly             "jpg:fig.jpg", "gif:blah.gif"
+#   3. specify subimage for multi-image format "tiff:file.tif[3]"
+#   4. raw images (row major format) specify geometry
+#                                      "raw:img[256x180]"
+#
+# IMREAD OPTIONS:
+# imread will support most of the options for convert.1
+#
+# imwrite( fname, img, options )
+# imwrite( fname, img, map, options )
+# imwrite( fname, r,g,b, options );
+#
+# where options is a string matrix (or list) of options
+#
+# example:   options= ["-rotate 25";
+#                      "-crop 200x200+150+150";
+#                      "-sample 200%" ];
+#   will rotate, crop, and then expand the image.
+#   note that the order of operations is important
+#
+# The following options are supported
+#  -antialias           remove pixel-aliasing
+#  -background color    background color
+#  -blur geometry       blur the image
+#  -border geometry     surround image with a border of color
+#  -bordercolor color   border color
+#  -box color           color for annotation bounding box
+#  -charcoal radius     simulate a charcoal drawing
+#  -colorize value      colorize the image with the fill color
+#  -colors value        preferred number of colors in the image
+#  -colorspace type     alternate image colorspace
+#  -comment string      annotate image with comment
+#  -compress type       type of image compression
+#  -contrast            enhance or reduce the image contrast
+#  -crop geometry       preferred size and location of the cropped image
+#  -density geometry    vertical and horizontal density of the image
+#  -depth value         depth of the image
+#  -despeckle           reduce the speckles within an image
+#  -dispose method      GIF disposal method
+#  -dither              apply Floyd/Steinberg error diffusion to image
+#  -draw string         annotate the image with a graphic primitive
+#  -edge radius         apply a filter to detect edges in the image
+#  -emboss radius       emboss an image
+#  -enhance             apply a digital filter to enhance a noisy image
+#  -equalize            perform histogram equalization to an image
+#  -fill color          color to use when filling a graphic primitive
+#  -filter type         use this filter when resizing an image
+#  -flip                flip image in the vertical direction
+#  -flop                flop image in the horizontal direction
+#  -font name           font for rendering text
+#  -frame geometry      surround image with an ornamental border
+#  -fuzz distance       colors within this distance are considered equal
+#  -gamma value         level of gamma correction
+#  -geometry geometry   perferred size or location of the image
+#  -gaussian geometry   gaussian blur an image
+#  -gravity type        vertical and horizontal text placement
+#  -implode amount      implode image pixels about the center
+#  -intent type         Absolute, Perceptual, Relative, or Saturation
+#  -interlace type      None, Line, Plane, or Partition
+#  -label name          assign a label to an image
+#  -level value         adjust the level of image contrast
+#  -list type           Color, Delegate, Format, Magic, Module, or Type
+#  -map filename        transform image colors to match this set of colors
+#  -matte               store matte channel if the image has one
+#  -median radius       apply a median filter to the image
+#  -modulate value      vary the brightness, saturation, and hue
+#  -monochrome          transform image to black and white
+#  -morph value         morph an image sequence
+#  -negate              replace every pixel with its complementary color 
+#  -noise radius        add or reduce noise in an image
+#  -normalize           transform image to span the full range of colors
+#  -opaque color        change this color to the fill color
+#  -page geometry       size and location of an image canvas
+#  -paint radius        simulate an oil painting
+#  -profile filename    add ICM or IPTC information profile to image
+#  -quality value       JPEG/MIFF/PNG compression level
+#  -raise value         lighten/darken image edges to create a 3-D effect
+#  -region geometry     apply options to a portion of the image
+#  -roll geometry       roll an image vertically or horizontally
+#  -rotate degrees      apply Paeth rotation to the image
+#  -sample geometry     scale image with pixel sampling
+#  -scale geometry      resize image
+#  -segment values      segment an image
+#  -seed value          pseudo-random number generator seed value
+#  -shade degrees       shade the image using a distant light source
+#  -sharpen geometry    sharpen the image
+#  -shave geometry      shave pixels from the image edges
+#  -shear geometry      slide one edge of the image along the X or Y axis
+#  -size geometry       width and height of image
+#  -solarize threshold  negate all pixels above the threshold level
+#  -spread amount       displace image pixels by a random amount
+#  -stroke color        color to use when stoking a graphic primitive
+#  -strokewidth value   width of stroke
+#  -swirl degrees       swirl image pixels about the center
+#  -texture filename    name of texture to tile onto the image background
+#  -threshold value     threshold the image
+#  -tile filename       tile image when filling a graphic primitive
+#  -transparent color   make this color transparent within the image
+#  -treedepth value     depth of the color tree
+#  -type type           image type
+#  -units type          PixelsPerInch, PixelsPerCentimeter, or Undefined
+#  -unsharp geometry    sharpen the image
+
+
+function imwrite(fname, p2, p3 ,p4 ,p5 );
+
+save_empty_list_elements_ok= empty_list_elements_ok;
+unwind_protect
+empty_list_elements_ok= 1;
+
+if  ( nargin <= 1 )     || ...
+    ( ! isstr (fname))  || ...
+    ( nargin == 2 && isstr(p2) )
+    usage([ ...
+    "imwrite( fname, img )\n", ...
+    "imwrite( fname, img, map )\n", ...
+    "imwrite( fname, r,g,b );\n", ...
+    "imwrite( fname, img, options )\n", ...
+    "imwrite( fname, img, map, options )\n", ...
+    "imwrite( fname, r,g,b, options );\n"]);
+endif
+
+# Put together the options string
+# TODO: add some error checking to options
+option_str="";
+n_mat= nargin-1;
+
+options= eval(sprintf("p%d",nargin));
+# process options strings if given
+if    isstr(options)
+   n_mat--;
+   for i= 1:size(options,1)
+      option_str=[option_str," ", options(i,:) ];
+   end
+elseif is_list( options )
+   n_mat--;
+   for i= 1:length(options)
+      option_str=[option_str," ", nth(options,i) ];
+   end
+end
+
+[hig,wid] = size(p2);
+if n_mat==1
+   data= p2';
+   outputtype="pgm";
+   pnm_sig="P5";
+elseif n_mat==2
+   img= p2';
+   data= [ 255*reshape(p3(img,1),1, hig*wid);
+           255*reshape(p3(img,2),1, hig*wid);
+           255*reshape(p3(img,3),1, hig*wid) ];
+   outputtype="ppm";
+   pnm_sig="P6";
+elseif n_mat==3
+   data= [ reshape(p2',1, hig*wid);
+           reshape(p3',1, hig*wid);
+           reshape(p4',1, hig*wid) ];
+   outputtype="ppm";
+   pnm_sig="P6";
+else
+   error("imwrite: too many data matrices specified");
+end
+
+   pname= sprintf("convert %s %s:- %s 2>/dev/null",
+                  option_str, outputtype, fname);
+   fid= popen(pname ,'w');
+#  disp(pname); disp(fid);
+   if fid<0;
+      fclose(fid);
+      error(['could not popen ',pname,'. Is imagemagick installed?']);
+   end
+
+   fprintf(fid,"%s\n%d %d\n255\n",pnm_sig,wid,hig);
+   write_count= fwrite(fid,data(:));
+   if write_count != prod(size(data))
+      fclose(fid);
+      error(['Unable to write image: ', fname ]);
+   end
+
+   fclose(fid);
+
+unwind_protect_cleanup
+empty_list_elements_ok= save_empty_list_elements_ok;
+end_unwind_protect
+
+#
+# $Log$
+# Revision 1.1  2002/03/11 01:56:47  aadler
+# general image read/write functionality using imagemagick utilities
+#
+#