TEMP: force RGB for grayscale PNG

Fix this error/warning message:
$ convert -colorspace sRGB test5.psd[318] f318.png
convert-im6.q16: profile 'icc': 'RGB ': RGB color space not permitted on grayscale PNG `f318.png' @ warning/png.c/MagickPNGWarningHandler/1668.

diff --git a/fgen.sh b/fgen.sh
index 2f1fb5b..8a700c7 100755 (executable)
--- a/fgen.sh
+++ b/fgen.sh
@@ -354,7 +354,7 @@ if [ ${trames} -eq 1 ]; then
             else
                 convert -colorspace sRGB -page +0+0 ${dest}/background.png \
                         ${files} -background none -layers merge \
-                        ${fname}
+                        PNG32:${fname}
             fi
 
             if [ x"${dup_from}" != x"" ]; then