diff --git a/pngzop_references.html b/pngzop_references.html
index f228bd6a8..a1d8ace8e 100644
--- a/pngzop_references.html
+++ b/pngzop_references.html
@@ -7,6 +7,9 @@
 Data_compression_using_Zopfli.pdf</a>
 <li><a href="http://zlib.net/pigz/">zlib.net/pigz</a> (parallel gzip)
 <li><a href="http://zlib.net/zlib/">zlib.net</a> (zlib/examples/zpipe.c)
+<li><a href="http://pmt.sourceforge.net/pngcrush/">pngcrush</a>
+<li><a href="http://libpng.sourceforge.net/>pngfix</a>
+(in contrib/tools of libpng-1.6.3 or later)
 </ul>
 </body>
 </html>
diff --git a/pngzop_results.txt b/pngzop_results.txt
deleted file mode 100644
index f5ee693db..000000000
--- a/pngzop_results.txt
+++ /dev/null
@@ -1,211 +0,0 @@
-
-Corpus contains 1734 PNG files from mozilla hg repo
-5491004 total bytes (complete PNG files)
-5019516 total bytes (IDAT chunk data)
-35154779 total bytes uncompressed IDATs
-
-mogrify -strip *.png
-added vpAG, bKGD, and pHYs chunks. (was old mogrify)
-scooby> time q16mogrify -strip *.png
-real	0m13.500s user	0m13.057s sys	0m0.424s
-5061691 total bytes (complete PNG files)
-
-Corpus divided into two parts: small, stripped PNGs less than 1024 bytes,
-and large, stripped PNGs greater than or equal to 1024 bytes.
-
-pngcrush -brute -d BF_brute *.png
-CPU time decoding 35.690, encoding 255.190, other 19.960, total 310.840 seconds
-4738882 total bytes (complete PNG files)
-4281038 total bytes (IDAT chunk data)
-
-6850560 2013-03-02 22:04 mozilla-corpus.tar
-4995464 2013-03-02 22:04 ../mozilla-corpus.tar.xz (xz)
-4994412 2013-03-02 22:04 ../mozilla-corpus.tar.xz (xz -9)
-
-scooby> time gzip -9n *.idat
-real	0m5.553s user	0m5.344s sys	0m0.200s
-time gzip -d *.gz
-real	0m0.778s user	0m0.552s sys	0m0.224s
-
-scooby> time gzip -9n *.idat
-real	0m5.648s user	0m5.436s sys	0m0.200s
-4360009 total bytes (includes 20820 bytes of gzip overhead)
-4339189 total bytes (without 20820 bytes of gzip overhead)
-scooby> time gunzip *.idat.gz
-real	0m0.762s user	0m0.568s sys	0m0.188s
-
-
-scooby> time bzip2 *idat
-real	0m3.830s user	0m3.452s sys	0m0.320s
-4015342 total bytes
-scooby> time bzip2 -d *bz2
-real	0m1.011s user	0m0.716s sys	0m0.292s
-
-
-scooby> time xz *idat
-real	0m14.621s user	0m14.305s sys	0m0.236s
-3813468 total bytes
-scooby> time xz -d *.xz
-real	0m0.716s user	0m0.452s sys	0m0.256s
-
-scooby> nohup time zopfli --zlib *.idat &
-587.24user 0.40system 9:48.10elapsed 
-4035633 total
-
-pngcrush -d PC_default *.png
-CPU time decoding 1.710, encoding 21.600, other 1.190, total 24.500 seconds
-4757749 total bytes (complete PNG files)
-4299905 total bytes (IDAT chunk data)
-
-scooby> time gzip -9n *.idat
-real	0m5.504s user	0m5.260s sys	0m0.236s
-   4369829 total
-scooby> time gunzip *gz
-real	0m0.791s user	0m0.576s sys	0m0.212s
-
-scooby> time xz *.idat
-real	0m14.481s user	0m14.145s sys	0m0.308s
-   3820192 total
-scooby> time xz -d *.xz
-real	0m0.693s user	0m0.468s sys	0m0.220s
-
-scooby> time bzip2 -9 *.idat
-real	0m3.603s user	0m3.220s sys	0m0.376s
-   4022529 total
-scooby> time bzip2 -d *bz2
-real	0m0.989s user	0m0.732s sys	0m0.252s
-
-time zopfli --zlib *.idat
-590.4 sec
-   4047719 total
-
-pngcrush -m 7 -force *.png # filter 0 level 9 strategy 0
-CPU time decoding 0.690, encoding 17.270, other 0.670, total 18.630 seconds
-5593778 total PNG size
-5136096 total IDAT size
-
-scooby> time gzip -n9 *.idat
-real	0m2.835s user	0m2.556s sys	0m0.268s
-   5153307 total
-scooby> time gunzip *.gz
-real	0m0.800s user	0m0.524s sys	0m0.272s
-scooby> time gzip -n9 *.idat
-real	0m7.134s user	0m6.812s sys	0m0.200s
-  4773010 total
-scooby> time gunzip *gz
-real	0m0.763s user	0m0.536s sys	0m0.224s
-
-
-scooby> time bzip2 -9 *.idat
-real	0m5.024s user	0m4.684s sys	0m0.308s
-   4614708 total
-scooby> time bzip2 -d *.bz2
-real	0m1.033s user	0m0.732s sys	0m0.296s
-
-scooby> time xz *.idat
-real	0m12.970s user	0m12.673s sys	0m0.280s
-  4138560 total
-scooby> time xz -d *xz 
-real	0m0.758s user	0m0.476s sys	0m0.280s
-
-zopli --zlib *.png
-98.45user 0.47system 1:39.12elapsed 99%CPU (0avgtext+0avgdata 40192maxresident)k
-4864938 
-
-pngcrush -m 6 -force *.png
-CPU time decoding 0.430, encoding 16.090, other 0.870, total 17.390 seconds
-4763290
-
-scooby> time gzip -n9 *.idat
-real	0m2.833s user	0m2.548s sys	0m0.236s
-4752190
-scooby> gunzip *gz
-real	0m0.767s user	0m0.580s sys	0m0.184s
-
-bzip2 -9
-real	0m2.523s user	0m2.164s sys	0m0.272s
-  5492706 total
-
-
-scooby> time xz *.idat
-real	0m15.198s user	0m14.873s sys	0m0.272s
-   4231288 total
-scooby> time xz -d *xz
-real	0m0.707s user	0m0.488s sys	0m0.216s
-
-zopfli
-91.32user 0.62system 1:32.02elapsed
-5153680
-
-nohup time pngcrush -brute -reduce -force -d PC_reduced *.png&
- CPU time decoding 36.160, encoding 244.460, other 16.910, total 297.530 seconds
-4108911
-
-time gzip -9n *.idat
-real	0m5.315s user	0m5.068s sys	0m0.240s
-   4187025 total
-time gunzip *.gz
-real	0m0.766s user	0m0.512s sys	0m0.252s
-
-scooby> time bzip2 -9 *.idat
-real	0m3.618s user	0m3.220s sys	0m0.328s
-   3844856 total
-
-scooby> time xz *.idat
-real	0m14.098s user	0m13.753s sys	0m0.284s
-  3651752 total
-
-zopfli
-81.01user 0.45system 1:21.59elapsed
-
-Summary:
-
-      Method           time   IDAT bytes
-    original files      n/a    5019516
-
-    pngcrush -brute   310.8    4281038
-    gzip -9n            5.6    4339189
-    zopfli --zlib     596.7    4035633
-    bzip2 -9            3.8    4015342
-    xz                 14.6    3813468
-
-    pngcrush default   24.5    4299905
-    gzip -9n            5.5    4349009
-    zopfli --zlib     590.4    4047719
-    bzip2 -9            3.6    4022529
-    xz                 14.5    3820192
-
-    pngcrush none      18.6    5136096
-    zopfli --zlib      98.9    4864938
-    gzip -n9            2.8    5132487
-    bzip2 -9            3.8    4614708
-    xz                 12.8    4138560
-
-    pngcrush adaptive  17.4    4763290
-    zopfli --zlib      99.0    5153680
-    gzip -n9            2.8    4752190
-    bzip2 -9            2.6    5492706
-    xz                 15.2    4231288
-
-    pngcrush -reduce  297.5    4108911
-    gzip -9n            5.3    4187025
-    zopfli --zlib      81.5    4461661
-    bzip2 -9            3.6    3844856
-    xz                 13.8    3651752
-
-
-    Kodak 24 test images (some rotated to portrait)
-    time zopfli --zlib *.idat
-    real	2m52.325s user	2m52.107s sys	0m0.060s
-     kodim*.png  15249498 total
-     kodim*.zdat 15246402 total
-     kodim*.zlib 14717411 total
-
-    Size range    pngcrush   zopfli    z/pc
-    0-200            11818    11618   .9831
-    201-1000        140290   136015   .9695
-    1001-10000     1040052  1000877   .9623
-    10001-200000   2756452  2568988   .9320
-    300000-450000   332611   318047   .9562
-    450001-999999 15246402 14717411   .9653
-
diff --git a/scooby-results.txt b/scooby-results.txt
deleted file mode 100644
index 0a97f51b4..000000000
--- a/scooby-results.txt
+++ /dev/null
@@ -1,171 +0,0 @@
-
-a
-/scratch/glennrp/ZZ/a
-pngcrush
-0.28user 0.13system 0:00.42elapsed 97%CPU (0avgtext+0avgdata 7616maxresident)k
-856inputs+3032outputs (1major+13991minor)pagefaults 0swaps
-  895  1631 46623 total
-pngcrush -brute
-6.60user 1.45system 0:08.10elapsed 99%CPU (0avgtext+0avgdata 7632maxresident)k
-0inputs+3032outputs (0major+143660minor)pagefaults 0swaps
-  914  1660 46368 total
-pngzop_pngcrush
-15.60user 5.94system 0:27.81elapsed 77%CPU (0avgtext+0avgdata 17104maxresident)k
-256inputs+9624outputs (1major+5472314minor)pagefaults 0swaps
-  900  1658 46145 total
-pngzop_brute
-119.13user 38.43system 0:43.11elapsed 365%CPU (0avgtext+0avgdata 17200maxresident)k
-16inputs+63808outputs (0major+28282648minor)pagefaults 0swaps
-  907  1666 46139 total
-
-b
-/scratch/glennrp/ZZ/b
-pngcrush
-1.09user 0.20system 0:01.30elapsed 99%CPU (0avgtext+0avgdata 7584maxresident)k
-0inputs+5848outputs (0major+40961minor)pagefaults 0swaps
-  2655   7715 354086 total
-pngcrush -brute
-17.20user 3.74system 0:21.02elapsed 99%CPU (0avgtext+0avgdata 7584maxresident)k
-0inputs+5840outputs (0major+816211minor)pagefaults 0swaps
-  2627   7592 351517 total
-pngzop_pngcrush
-57.00user 10.76system 1:19.73elapsed 84%CPU (0avgtext+0avgdata 14352maxresident)k
-0inputs+18976outputs (0major+10346028minor)pagefaults 0swaps
-  2609   7379 347229 total
-pngzop_brute
-371.07user 67.23system 1:53.12elapsed 387%CPU (0avgtext+0avgdata 14432maxresident)k
-0inputs+125536outputs (0major+53809985minor)pagefaults 0swaps
-  2579   7340 346825 total
-
-c
-/scratch/glennrp/ZZ/c
-pngcrush
-2.27user 0.24system 0:02.53elapsed 99%CPU (0avgtext+0avgdata 7648maxresident)k
-80inputs+3904outputs (0major+44991minor)pagefaults 0swaps
-  4423  18786 862928 total
-pngcrush -brute
-35.26user 2.58system 0:37.93elapsed 99%CPU (0avgtext+0avgdata 7648maxresident)k
-0inputs+3896outputs (0major+408699minor)pagefaults 0swaps
-  4361  18766 858463 total
-pngzop_pngcrush
-104.93user 7.65system 2:00.50elapsed 93%CPU (0avgtext+0avgdata 72224maxresident)k
-0inputs+17576outputs (0major+7394969minor)pagefaults 0swaps
-  4218  18601 838686 total
-pngzop_brute
-658.97user 49.82system 2:52.64elapsed 410%CPU (0avgtext+0avgdata 72304maxresident)k
-0inputs+114424outputs (0major+40850802minor)pagefaults 0swaps
-  4257  18413 837426 total
-
-d
-/scratch/glennrp/ZZ/d
-pngcrush
-9.19user 0.21system 0:09.42elapsed 99%CPU (0avgtext+0avgdata 7680maxresident)k
-0inputs+3992outputs (0major+116721minor)pagefaults 0swaps
-   7364   41546 1903162 total
-pngcrush -brute
-116.36user 3.20system 1:59.67elapsed 99%CPU (0avgtext+0avgdata 7664maxresident)k
-0inputs+3992outputs (0major+1804892minor)pagefaults 0swaps
-   7350   41372 1895523 total
-pngzop_pngcrush
-442.75user 3.94system 7:28.62elapsed 99%CPU (0avgtext+0avgdata 63888maxresident)k
-0inputs+35920outputs (0major+3546630minor)pagefaults 0swaps
-   6962   39478 1767997 total
-pngzop_brute
-2439.72user 20.39system 7:48.45elapsed 525%CPU (0avgtext+0avgdata 80224maxresident)k
-32inputs+230680outputs (0major+15883572minor)pagefaults 0swaps
-   6976   39490 1767559 total
-
-e
-/scratch/glennrp/ZZ/e
-pngcrush
-2.14user 0.00system 0:02.15elapsed 99%CPU (0avgtext+0avgdata 7312maxresident)k
-0inputs+656outputs (0major+1986minor)pagefaults 0swaps
-  1455   8129 335339 ie_pc.png
-pngcrush -brute
-19.64user 0.09system 0:19.75elapsed 99%CPU (0avgtext+0avgdata 7360maxresident)k
-0inputs+656outputs (0major+31375minor)pagefaults 0swaps
-   432   4399 332668 ie_bf.png
-pngzop_pngcrush
-40.27user 0.01system 0:40.33elapsed 99%CPU (0avgtext+0avgdata 74320maxresident)k
-0inputs+5152outputs (0major+13657minor)pagefaults 0swaps
-   940   6117 317125 ie_pngzop.png
-pngzop_brute
-239.30user 0.14system 0:43.02elapsed 556%CPU (0avgtext+0avgdata 82912maxresident)k
-0inputs+32960outputs (0major+66496minor)pagefaults 0swaps
-   940   6117 317125 ie_pngzop_brute.png
-
-f
-/scratch/glennrp/ZZ/f
-pngcrush
-10.48user 0.05system 0:10.55elapsed 99%CPU (0avgtext+0avgdata 7600maxresident)k
-0inputs+8544outputs (0major+12446minor)pagefaults 0swaps
-  16040   88064 4357651 total
-pngcrush -brute
-143.58user 0.68system 2:24.40elapsed 99%CPU (0avgtext+0avgdata 7456maxresident)k
-0inputs+8520outputs (0major+247399minor)pagefaults 0swaps
-  16087   89458 4346809 total
-pngzop_pngcrush
-111.85user 0.22system 1:52.24elapsed 99%CPU (0avgtext+0avgdata 64464maxresident)k
-0inputs+35216outputs (0major+103379minor)pagefaults 0swaps
-  15330   87361 4167473 total
-pngzop_brute
-538.88user 1.01system 1:38.01elapsed 550%CPU (0avgtext+0avgdata 80528maxresident)k
-0inputs+235432outputs (0major+386614minor)pagefaults 0swaps
-  15330   87361 4167473 total
-
-g
-/scratch/glennrp/ZZ/g
-pngcrush
-9.18user 0.05system 0:09.24elapsed 99%CPU (0avgtext+0avgdata 7456maxresident)k
-0inputs+11160outputs (0major+13841minor)pagefaults 0swaps
-  20369  116425 5694210 total
-pngcrush -brute
-135.51user 0.87system 2:16.51elapsed 99%CPU (0avgtext+0avgdata 7456maxresident)k
-0inputs+11128outputs (0major+277945minor)pagefaults 0swaps
-  20572  116699 5676667 total
-pngzop_pngcrush
-103.02user 0.25system 1:43.37elapsed 99%CPU (0avgtext+0avgdata 68976maxresident)k
-0inputs+42632outputs (0major+103176minor)pagefaults 0swaps
-  20331  115203 5447000 total
-pngzop_brute
-525.62user 1.00system 1:34.61elapsed 556%CPU (0avgtext+0avgdata 83728maxresident)k
-0inputs+284472outputs (0major+451658minor)pagefaults 0swaps
-  20444  117512 5440483 total
-
-h
-/scratch/glennrp/ZZ/h
-pngcrush
-5.31user 0.03system 0:05.35elapsed 99%CPU (0avgtext+0avgdata 7616maxresident)k
-0inputs+10312outputs (0major+11047minor)pagefaults 0swaps
-  19671  112525 5263535 total
-pngcrush -brute
-86.52user 0.71system 1:27.32elapsed 99%CPU (0avgtext+0avgdata 7456maxresident)k
-0inputs+10240outputs (0major+216611minor)pagefaults 0swaps
-  19547  109623 5225980 total
-pngzop_pngcrush
-67.07user 0.17system 1:07.29elapsed 99%CPU (0avgtext+0avgdata 78944maxresident)k
-0inputs+36376outputs (0major+84000minor)pagefaults 0swaps
-  18817  106842 5077291 total
-pngzop_brute
-363.02user 0.84system 1:04.50elapsed 564%CPU (0avgtext+0avgdata 80912maxresident)k
-0inputs+243320outputs (0major+347055minor)pagefaults 0swaps
-  18977  107006 5077025 total
-
-i
-/scratch/glennrp/ZZ/i
-pngcrush
-7.63user 0.04system 0:07.68elapsed 99%CPU (0avgtext+0avgdata 7552maxresident)k
-0inputs+1768outputs (0major+11345minor)pagefaults 0swaps
-  3365  19152 888909 total
-pngcrush -brute
-70.08user 0.54system 1:10.69elapsed 99%CPU (0avgtext+0avgdata 7392maxresident)k
-0inputs+1760outputs (0major+215227minor)pagefaults 0swaps
-  3339  19069 888023 total
-pngzop_pngcrush
-203.64user 0.25system 3:24.19elapsed 99%CPU (0avgtext+0avgdata 257024maxresident)k
-0inputs+21824outputs (0major+179439minor)pagefaults 0swaps
-  3123  17887 828950 total
-pngzop_brute
-1162.93user 1.66system 3:44.79elapsed 518%CPU (0avgtext+0avgdata 280768maxresident)k
-0inputs+138608outputs (0major+1071825minor)pagefaults 0swaps
-  3215  17897 827208 total
diff --git a/scooby-summary.txt b/scooby-summary.txt
deleted file mode 100644
index 919e4d7c1..000000000
--- a/scooby-summary.txt
+++ /dev/null
@@ -1,47 +0,0 @@
-
-Scooby results with zopfli --I25:
-
-a pngcrush         0.28user 0.13system 0:00.42elapsed  46623 total
-  pngcrush -brute  6.60user 1.45system 0:08.10elapsed  46368 total
-  pngzop_pngcrush 15.60user 5.94system 0:27.81elapsed  46145 total
-  pngzop_brute   119.13user 38.43system 0:43.11elapsed 46139 total
-
-b pngcrush         1.09user 0.20system 0:01.30elapsed  354086 total
-  pngcrush -brute 17.20user 3.74system 0:21.02elapsed  351517 total
-  pngzop_pngcrush 57.00user 10.76system 1:19.73elapsed 347229 total
-  pngzop_brute   371.07user 67.23system 1:53.12elapsed 346825 total
-
-c pngcrush          2.27user 0.24system 0:02.53elapsed  862928 total
-  pngcrush -brute  35.26user 2.58system 0:37.93elapsed  858463 total
-  pngzop_pngcrush 104.93user 7.65system 2:00.50elapsed  838686 total
-  pngzop_brute    658.97user 49.82system 2:52.64elapsed 837426 total
-
-d pngcrush          9.19user 0.21system 0:09.42elapsed  1903162 total
-  pngcrush -brute 116.36user 3.20system 1:59.67elapsed  1895523 total
-  pngzop_pngcrush 442.75user 3.94system 7:28.62elapsed  1767997 total
-  pngzop_brute   2439.72user 20.39system 7:48.45elapsed 1767559 total
-
-e pngcrush         2.14user 0.00system 0:02.15elapsed 335339 ie_pc.png
-  pngcrush -brute 19.64user 0.09system 0:19.75elapsed 332668 ie_bf.png
-  pngzop_pngcrush 40.27user 0.01system 0:40.33elapsed 317125 ie_pngzop.png
-  pngzop_brute   239.30user 0.14system 0:43.02elapsed 317125 ie_pngzop_brute.png
-
-f pngcrush        10.48user 0.05system 0:10.55elapsed 4357651 total
-  pngcrush -brute143.58user 0.68system 2:24.40elapsed 4346809 total
-  pngzop_pngcrush111.85user 0.22system 1:52.24elapsed 4167473 total
-  pngzop_brute   538.88user 1.01system 1:38.01elapsed 4167473 total
-
-g pngcrush          9.18user 0.05system 0:09.24elapsed 5694210 total
-  pngcrush -brute 135.51user 0.87system 2:16.51elapsed 5676667 total
-  pngzop_pngcrush 103.02user 0.25system 1:43.37elapsed 5447000 total
-  pngzop_brute    525.62user 1.00system 1:34.61elapsed 5440483 total
-
-h pngcrush          5.31user 0.03system 0:05.35elapsed 5263535 total
-  pngcrush -brute  86.52user 0.71system 1:27.32elapsed 5225980 total
-  pngzop_pngcrush  67.07user 0.17system 1:07.29elapsed 5077291 total
-  pngzop_brute    363.02user 0.84system 1:04.50elapsed 5077025 total
-
-i pngcrush          7.63user 0.04system 0:07.68elapsed  888909 total
-  pngcrush -brute  70.08user 0.54system 1:10.69elapsed  888023 total
-  pngzop_pngcrush 203.64user 0.25system 3:24.19elapsed  828950 total
-  pngzop_brute   1162.93user 1.66system 3:44.79elapsed  827208 total