1 files changed, 110 insertions, 0 deletions
diff --git a/pkg/proto/epix.x b/pkg/proto/epix.x
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+++ b/pkg/proto/epix.x
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+include	<imhdr.h>
+
+# EPIX -- Edit the value of a pixel in a two dimensional array.  Fetch
+# subraster surrouding pixel, print on standard output.  Compute median
+# value and set default value of new pixel value parameter, then prompt
+# for actual value and edit image.
+
+procedure t_epix()
+
+char	image_name[SZ_FNAME]
+int	xcoord, ycoord
+int	x1, x2, y1, y2, m, n
+int	npix, ncols, nlines, boxsize, half_size, sample_size
+real	median_value, ksigma, mean, sigma
+pointer	ahdr, a
+
+bool	clgetb()
+int	clgeti(), aravr()
+real	clgetr()
+pointer	immap(), imgs2r(), imps2r()
+
+begin
+	# Get image name and map image.
+	call clgstr ("image_name", image_name, SZ_FNAME)
+	ahdr = immap (image_name, READ_WRITE, 0)
+
+	ncols  = IM_LEN(ahdr,1)
+	nlines = IM_LEN(ahdr,2)
+
+	# Get pixel coordinates, size of subraster.
+
+	xcoord	= clgeti ("xcoord")
+	ycoord	= clgeti ("ycoord")
+	boxsize	= clgeti ("boxsize")
+	ksigma	= clgetr ("ksigma")
+
+	# Fetch subraster surrounding pixel.
+
+	half_size = max (1, boxsize / 2)
+	x1 = max (1,      xcoord - half_size)
+	x2 = min (ncols,  xcoord + half_size)
+	y1 = max (1,      ycoord - half_size)
+	y2 = min (nlines, ycoord + half_size)
+
+	a = imgs2r (ahdr, x1, x2, y1, y2)
+
+	# Print subraster on standard output.
+
+	if (clgetb ("verbose")) {
+	    m = x2 - x1 + 1
+	    n = y2 - y1 + 1
+	    call print_subraster (Memr[a], m, n, x1, x2, y1, y2)
+
+	    # Compute and print the median pixel value, and the mean value
+	    # excluding the central pixel.
+
+	    npix = m * n
+	    call asrtr (Memr[a], Memr[a], npix)
+	    median_value = Memr[a + (npix+1)/2 - 1]
+	    sample_size = aravr (Memr[a], npix, mean, sigma, ksigma)
+
+	    call printf ("median %g, mean %g, sigma %g, sample %d pixels\n")
+		call pargr (median_value)
+		call pargr (mean)
+		call pargr (sigma)
+		call pargi (sample_size)
+	}
+
+	if (clgetb ("edit_image")) {
+	    # Edit the image.
+	    a = imps2r (ahdr, xcoord, xcoord, ycoord, ycoord)
+	    Memr[a] = clgetr ("new_value")
+	}
+
+	call imunmap (ahdr)
+end
+
+
+# PRINT_SUBRASTER -- Print the values of the pixels in a subraster on the
+# standard output.
+
+procedure print_subraster (a, m, n, x1, x2, y1, y2)
+
+real	a[m,n]
+int	m, n
+int	x1, x2, y1, y2
+int	column, line
+
+begin
+	# Print column labels.
+
+	call printf ("%7w")
+	do column = x1, x2 {
+	    call printf ("%8d ")
+		call pargi (column)
+	}
+	call printf ("\n")
+
+	# Print line labels and pixel values.
+
+	do line = y1, y2 {
+	    call printf ("%8d ")
+		call pargi (line)
+	    do column = x1, x2 {
+		call printf ("%8.6g ")
+		    call pargr (a[column-x1+1, line-y1+1])
+	    }
+	    call printf ("\n")
+	}
+end