--- a/tests/falsecolor_test.pl	Sun Jun 26 21:32:00 2011 +0100
+++ b/tests/falsecolor_test.pl	Sun Jun 26 22:36:43 2011 +0100
@@ -1,5 +1,11 @@
 #!/usr/bin/perl
 
+# falsecolor_test.pl
+# This file is part of the testsuite of the Radiance csh2perl project.
+# You may copy and modify this file as basis for other tests.
+#
+# (c) Axel Jacobs, 26 June 2011
+
 use strict;
 use warnings;
 
@@ -10,34 +16,43 @@
 
 use File::Temp qw/ tempdir /;
 my $tmpdir = tempdir( CLEANUP => 0 );
-print "temp dir: $tmpdir\n";
 
 my $img = "data/images/street-rgbe_rle_400x400.hdr";
 
+# Options are arrays of [STDIN, command-line options].
+# Please include the pipe symbol as part of STDIN.
+# Put a leading space in front of STDIN to line up the output.
 my @options = (
-		"-ip $img",
-		"-ip $img -l cd/m2",   # Label now defaults to cd/m2, not nits.
-		"-i $img -p $img -l cd/m2",
-		"-ip $img -cl -l cd/m2",
-		"-ip $img -n 10 -l cd/m2",
-		"-ip $img -s 2000 -l cd/m2",
-		"-ip $img -lw 200 -lh 300 -l cd/m2",   # scale is slightly higher now.
+		["", "-ip $img"],
+		["", "-ip $img -l cd/m2"],   # Label now defaults to cd/m2, not nits.
+		["", "-i $img -p $img -l cd/m2"],
+		["", "-ip $img -cl -l cd/m2"],
+		["", "-ip $img -n 10 -l cd/m2"],
+		["", "-ip $img -s 2000 -l cd/m2"],
+		[" cat $img |", "-ip - -s 2000 -l cd/m2"],   # take image from STDIN.
+		["", "-ip $img -lw 200 -lh 300 -l cd/m2"],   # scale is slightly higher now.
 );
 
 # Run old CSH and new Perl script with different options,
 # compare the resulting images.
+my $total = 0;
+my $fail = 0;
 my $index = 0;
-my $opt;
-foreach $opt (@options) {
+my $opts;
+foreach $opts (@options) {
+		my $stdin = @$opts[0];
+		my $args = @$opts[1];
+		$total++;
+
 		my $cshout = "$tmpdir/${script}_csh$index.hdr";
-		my $cshcmd = "$script.csh $opt > $cshout";
-		print "  $cshcmd\n";
-		system "csh ../orig/$cshcmd";
+		my $cshcmd = "$script.csh $args > $cshout";
+		print " $stdin $cshcmd\n";
+		system "$stdin csh ../orig/$cshcmd";
 
 		my $perlout = "$tmpdir/${script}_perl$index.hdr";
-		my $perlcmd = "$script.pl $opt > $perlout";
-		print "  $perlcmd\n";
-		system "perl ../bin/$perlcmd";
+		my $perlcmd = "$script.pl $args > $perlout";
+		print " $stdin $perlcmd\n";
+		system "$stdin perl ../bin/$perlcmd";
 
 		my $diffimg = "$tmpdir/${script}_diff$index.hdr";
 		my $uval = &compare_images("$cshout", "$perlout", "$diffimg");
@@ -46,8 +61,11 @@
 			system "ximage $diffimg";
 		} else {
 			print "      Ok: Images $cshout and $perlout are identical.\n";
+			$fail++;
 		}
 }
+
+print "$fail of $total tests failed.\n";
 print "temp dir $tmpdir not removed. Please remove manually.\n";
 
 sub compare_images() {