Backport pnmcolormap2 test from 11.5.x to 11.2.x

See also https://bugs.gentoo.org/907295

--- a/test/pnmcolormap2.test
+++ b/test/pnmcolormap2.test
@@ -5,51 +5,143 @@
 tmpdir=${tmpdir:-/tmp}
 map=${tmpdir}/map.ppm
 
-echo "Test.  Should print 'match' eight times."
-# Threshold values (targetN=xx.xx) here were produced by calculating
-# the S/N ratio with reduced colors.
+echo "Test.  Should print 'match' eighteen times."
+
+# Threshold values (tgtN=xx.xx) were produced by calculating
+# the S/N ratio when the original image is compared against a
+# reference image with fewer colors than the target output image.
 
 # colors in following tests / colors for calculating threshold
-# 100 /  90
-# 200 / 180
-#  30 /  25
+# 256 / 224
+# 128 /  96  -splitspread
+# 128 / 108  other
+#  64 /  44  -center (default)
+#  64 /  48  -splitspread
+#  64 /  56  other
+
+# -center
+echo pnmcolormap  256
+tgt1=37.19;  tgt2=37.86;  tgt3=37.77
+pnmcolormap 256 testimg.ppm > ${map}
+pnmremap -mapfile=${map} testimg.ppm |\
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
+rm ${map}
+
+echo pnmcolormap  128
+tgt1=34.46;  tgt2=35.61;  tgt3=34.97
+pnmcolormap 128 testimg.ppm > ${map}
+pnmremap -mapfile=${map} testimg.ppm |\
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
+rm ${map}
+
+echo pnmcolormap  64
+tgt1=30.30;  tgt2=33.10;  tgt3=31.74
+pnmcolormap 64 testimg.ppm > ${map}
+pnmremap -mapfile=${map} testimg.ppm |\
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
+rm ${map}
+
+echo pnmcolormap -meancolor 256
+tgt1=38.36;  tgt2=38.63;  tgt3=38.95
+pnmcolormap -meancolor 256 testimg.ppm > ${map}
+pnmremap -mapfile=${map} testimg.ppm |\
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
+rm ${map}
+
+echo pnmcolormap -meancolor 128
+tgt1=35.86;  tgt2=37.17;  tgt3=36.65
+pnmcolormap -meancolor 128 testimg.ppm > ${map}
+pnmremap -mapfile=${map} testimg.ppm |\
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
+rm ${map}
+
+echo pnmcolormap -meancolor 64
+tgt1=33.64;  tgt2=34.92;  tgt3=34.44
+pnmcolormap -meancolor 64 testimg.ppm > ${map}
+pnmremap -mapfile=${map} testimg.ppm |\
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
+rm ${map}
+
+echo pnmcolormap -meanpixel 256
+tgt1=38.40;  tgt2=38.65;  tgt3=38.90
+pnmcolormap -meanpixel 256 testimg.ppm > ${map}
+pnmremap -mapfile=${map} testimg.ppm |\
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
+rm ${map}
+
+echo pnmcolormap -meanpixel 128
+tgt1=35.75;  tgt2=37.13;  tgt3=36.69
+pnmcolormap -meanpixel 128 testimg.ppm > ${map}
+pnmremap -mapfile=${map} testimg.ppm |\
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
+rm ${map}
+
+echo pnmcolormap -meanpixel 64
+tgt1=33.75;  tgt2=34.79;  tgt3=34.53
+pnmcolormap -meanpixel 64 testimg.ppm > ${map}
+pnmremap -mapfile=${map} testimg.ppm |\
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
+rm ${map}
+
+echo pnmcolormap -spreadluminosity 256
+tgt1=36.82;  tgt2=36.87;  tgt3=37.25
+pnmcolormap -spreadluminosity 256 testimg.ppm > ${map}
+pnmremap -mapfile=${map} testimg.ppm |\
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
+rm ${map}
 
-pnmcolormap 100 testimg.ppm > ${map}
+echo pnmcolormap -spreadluminosity 128
+tgt1=34.61;  tgt2=33.40;  tgt3=34.66
+pnmcolormap -spreadluminosity 128 testimg.ppm > ${map}
 pnmremap -mapfile=${map} testimg.ppm |\
-  pnmpsnr -target1=33.42 -target2=35.14 -target3=34.35 testimg.ppm -
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
 rm ${map}
 
-pnmcolormap -meancolor 100 testimg.ppm > ${map}
+echo pnmcolormap -spreadluminosity 64
+tgt1=32.35;  tgt2=30.23;  tgt3=32.35
+pnmcolormap -spreadluminosity 64 testimg.ppm > ${map}
 pnmremap -mapfile=${map} testimg.ppm |\
-  pnmpsnr -target1=34.91 -target2=36.86 -target3=35.84 testimg.ppm -
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
 rm ${map}
 
-pnmcolormap -meanpixel 100 testimg.ppm > ${map}
+echo pnmcolormap -splitcolorct 256
+tgt1=37.55;  tgt2=38.37;  tgt3=38.04
+pnmcolormap -splitcolorct 256 testimg.ppm > ${map}
 pnmremap -mapfile=${map} testimg.ppm |\
-  pnmpsnr -target1=34.95 -target2=36.77 -target3=35.81 testimg.ppm -
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
 rm ${map}
 
-pnmcolormap -spreadluminosity 100 testimg.ppm > ${map}
+echo pnmcolormap -splitcolorct 128
+tgt1=34.84;  tgt2=35.72;  tgt3=34.64
+pnmcolormap -splitcolorct 128 testimg.ppm > ${map}
 pnmremap -mapfile=${map} testimg.ppm |\
-  pnmpsnr -target1=33.71 -target2=32.91 -target3=33.93 testimg.ppm -
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
 rm ${map}
 
-pnmcolormap -splitcolorct 100 testimg.ppm > ${map}
+echo pnmcolormap -splitcolorct 64
+tgt1=31.56;  tgt2=33.74;  tgt3=32.93
+pnmcolormap -splitcolorct 64 testimg.ppm > ${map}
 pnmremap -mapfile=${map} testimg.ppm |\
-  pnmpsnr -target1=33.97 -target2=35.34 -target3=34.23 testimg.ppm -
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
 rm ${map}
 
-pnmcolormap -splitspread 100 testimg.ppm > ${map}
+echo pnmcolormap -splitspread 256
+tgt1=35.18;  tgt2=37.26;  tgt3=36.17
+pnmcolormap -splitspread 256 testimg.ppm > ${map}
 pnmremap -mapfile=${map} testimg.ppm |\
-  pnmpsnr -target1=32.98 -target2=35.06 -target3=33.19 testimg.ppm -
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
 rm ${map}
 
-pnmcolormap 200 testimg.ppm > ${map}
+echo pnmcolormap -splitspread 128
+tgt1=33.18;  tgt2=35.58;  tgt3=33.71
+pnmcolormap -splitspread 128 testimg.ppm > ${map}
 pnmremap -mapfile=${map} testimg.ppm |\
-  pnmpsnr -target1=36.14 -target2=36.87 -target3=36.79 testimg.ppm -
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
 rm ${map}
 
-pnmcolormap 30 testimg.ppm > ${map}
+echo pnmcolormap -splitspread 64
+tgt1=31.27;  tgt2=33.03;  tgt3=30.97
+pnmcolormap -splitspread 64 testimg.ppm > ${map}
 pnmremap -mapfile=${map} testimg.ppm |\
-  pnmpsnr -target1=28.53 -target2=31.62 -target3=29.99 testimg.ppm -
+pnmpsnr -target1=${tgt1} -target2=${tgt2} -target3=${tgt3} testimg.ppm -
 rm ${map}
--- a/test/pnmcolormap2.ok
+++ b/test/pnmcolormap2.ok
@@ -1,9 +1,37 @@
-Test.  Should print 'match' eight times.
+Test.  Should print 'match' eighteen times.
+pnmcolormap 256
 match
+pnmcolormap 128
 match
+pnmcolormap 64
 match
+pnmcolormap -meancolor 256
 match
+pnmcolormap -meancolor 128
 match
+pnmcolormap -meancolor 64
 match
+pnmcolormap -meanpixel 256
 match
+pnmcolormap -meanpixel 128
+match
+pnmcolormap -meanpixel 64
+match
+pnmcolormap -spreadluminosity 256
+match
+pnmcolormap -spreadluminosity 128
+match
+pnmcolormap -spreadluminosity 64
+match
+pnmcolormap -splitcolorct 256
+match
+pnmcolormap -splitcolorct 128
+match
+pnmcolormap -splitcolorct 64
+match
+pnmcolormap -splitspread 256
+match
+pnmcolormap -splitspread 128
+match
+pnmcolormap -splitspread 64
 match