                                The Art
                              of Lossless
                           Data Compression
                                vol. 19g

Here are the results of tests performed in June 2000 to compare
lossless compression of True Color (24-bit) images by all known programs
developed for such purpose, including BMF, JPEG-LS and PNG software,
7-Zip, Pkzip, and archivers with special algorithms for 24-bit images.

See Archive Comparison Test by Jeff Gilchrist for more info: http://act.by.net

If anybody wants to start or continue such tests,
or can suggest some other sets of images, or other compression programs,
 (not sources or algorithm descriptions, executable programs only)
or knows we have missed something important,
 (some new fantastic technology, an algorithm or even a program capable
 of lossless compression of up to 1000:1 and lossy compression of
 up to 10000:1, we hear about it from time to time since our XTs)
please let us know immediately: artest@hotmail.ru   Thank you!


[[1]] COMPRESSION QUALITY
=========================
             (see also
             [[2]] Speed
             [[3]] Details
             [[4]] Comments)

The last eleventh line shows results for the sum of all ten tests (336 images)

Original  BMF    RKim     RK     UHIC  ArHanGeL   NK     Eri     RAR     Imp
275.95%  100%   101.59  120.20  100.55  110.52  112.65  117.81  133.15  154.65
289.11%  100%   124.50  127.28  104.88  114.61  135.54  122.36  140.60  152.88
245.22%  100%   101.38  123.16  107.93  112.92  111.48  123.50  124.25  144.52
238.64%  100%   112.66  124.20  104.20  110.53  120.45  121.23  132.94  146.59
457.28% 101.93   100%   133.41  110.74  112.34  120.22  125.22  146.11  157.63
234.93%  100%   101.72  119.42  107.07  110.08  106.85  121.92  125.63  143.10
278.95%  100%   103.17  123.14  103.40  109.60  110.16  119.57  135.88  146.37
332.49%  100%   102.12  126.63  105.92  111.58  112.18  120.18  139.49  153.56
225.19%  100%   104.47  118.81  104.00  108.82  110.47  118.20  122.22  141.08
547.50%  100%   104.25  131.46  104.84  107.76  127.75  115.26  170.38  157.56
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
286.32%  100%   102.98  122.95  105.47  110.35  111.15  120.43  133.89  147.68

JPEG-LS  SPIHT   BTPC  {       Display        }  SEA   PngCrush  7-Zip   PkZip
149.81% 115.50  164.36  157.93  156.06  153.89  150.94  150.33  159.16  169.90
156.41% 136.11  170.42  177.21  169.62  164.86  163.71  151.73  205.21  211.56
119.20% 111.39  129.21  140.98  141.56  139.53  146.28  129.83  193.86  196.55
127.45% 122.73  137.49  146.42  145.46  144.00  147.31  134.68  182.24  185.85
172.49% 224.13  201.52  187.28  156.67  156.16  160.57  145.35  185.82  188.99
112.56% 111.61  119.89  129.58  132.73  129.30  137.85  120.59  170.09  172.74
118.69% 119.12  131.29  140.90  139.04  137.13  143.73  129.64  171.53  175.85
123.33% 117.86  136.63  145.92  143.78  142.44  151.77  133.46  197.76  202.49
117.84% 109.95  122.53  133.78  135.20  132.58  139.93  121.86  179.50  181.44
151.17% 132.31  176.94  164.21  150.26  148.74  156.87  142.19  186.28  195.55
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
121.48% 117.50  132.78  140.67  139.78  137.42  144.92  128.95  179.40  183.54


[[2]] Speed
===========
A set of 230 images totalling 271,331,460 bytes
from ftp://ipl.rpi.edu/pub/image/still/KodakImages/color/
was used for this test and an AMD-K6-400 machine with 64M RAM and Windows98.
Well-known 23 Kodak images copied ten times (see icopy.bat in artest19.zip)

 Programs,options        Overall      Average      Compress Extract  Compressed
                          score,       Users'        time,   time,     size,
                                       score,       seconds seconds    bytes
                      seconds  %    seconds  %
+7-zip  a             44471   146%  43736   147%      817     137    156662222
+7-zip  a -mx         44960   148%  43743   147%     1352     138    156492462
+arhangel a -mm -mz   34295   113%  31998   108%     2552    1557    108669974
+arhangel a -mm       34260   112%  31989   108%     2523    1551    108669974
+arhangel a -mm1      48908   161%  45779   154%     3476    2633    154074824
+arhangel a -mm3      42870   141%  40214   135%     2951    1879    136944664
 bmf   -f  -s  -q9    38628   127%  30978   104%     8500    2816     98323280
 bmf   -f  -s         33477   110%  30467   103%     3345    2820     98323280
 bmf   -f  -q9        33681   111%  29829   100%     4280     249    104947560
 bmf   -f             30324   100%  29572   100%      836     258    105229600
 eri   a -3ma8        31885   105%  30118   101%     1963     449    106102020
 eri   a -3ma8 -m3    31413   103%  30078   101%     1483     435    106182410
 eri   a -3ma8 -m2    31255   103%  30290   102%     1072     355    107379300
 eri   a -3ma8 -m1    32073   105%  31299   105%      860     299    111292130
+imp98   a -2         38040   125%  37366   126%      749     222    133449566
+imp98   a -2  -s4    38123   125%  37453   126%      744     218    133779179
+imp98   a -mm        43242   142%  42363   143%      977     110    151758474
+imp98   a -mm -s4    43204   142%  42299   143%     1006     109    151521544
+imp98   a -mm -m3    43528   143%  42174   142%     1505     119    150856163
+imp98   a -mm -m1    46105   152%  45522   153%      648     111    163246850
+imp-dos a -mm -m3    43565   143%  42194   142%     1524     137    150855710
 Nk                   35338   116%  31666   107%     4080     489    110767370
 pkzip  -exx          46871   154%  46394   156%      530     146    166302252
 pkzip  -a            46708   154%  46380   156%      365     146    166309392
 pkzip  -es           55426   182%  55211   186%      238     152    198128322
+pkzip32 -add -max    47059   155%  46592   157%      519     138    167047382
+pkzip32 -add         47018   155%  46662   157%      396     136    167349362
+WinRar  a -mm -mde   37138   122%  36685   124%      504     259    130951080
+WinRar  a -mm -m5    37149   122%  36678   124%      523     259    130921330
+WinRar  a -mm -s-    37137   122%  36685   124%      503     259    130951080
+WinRar  a -mm -s     37124   122%  36648   123%      529     258    130813550
+WinRar  a -mmf       36740   121%  36324   122%      462     267    129638820
+rar32   a -mm -mde   37254   122%  36731   124%      582     297    130951080
+rar32   a -mm -m5    37263   122%  36724   124%      599     297    130921330
+rar32   a -mm -s-    37253   122%  36730   124%      581     297    130951080
+rar32   a -mm -s     37236   122%  36692   124%      605     294    130813550
+rar32   a -mmf       36860   121%  36371   122%      543     306    129638820
+rk    -mx2           27554    90%* 16839    56%*   11906   12305     12035652
+rk    -mx1           46827   154%* 37353   126%*   10527   11174     90452920
+rk    -mf3            7011    23%*  5469    18%*    1713    1191     14784112
+rk    -mf2            7863    25%*  6571    22%*    1435    1176     18906828
+rk    -mf1           39048   128%* 37937   128%*    1235     887    132934712
+rkim  cx             35399   116%  30769   104%     5144    2506     99896080
+rkim  c              32861   108%  31261   105%     1778    2178    104059250
 uhic  m              36260   119%  32373   109%     4319    4477     98870920
 uhic  e              32812   108%  30565   103%     2496    2501    100132460
 Alchemy ---n         46843   154%  44143   149%     3000     526    155940956
         ---n 3       46602   153%  44584   150%     2242     648    157361419
         ---n 2       46338   152%  44670   151%     1853     437    158572986
         ---n 1       45301   149%  43610   147%     1879     434    154758370
 SEA /png:100         42487   140%  41480   140%     1119     142    148414950
 Display -i --same -bpng
+  filter=5,level=9   44739   147%  42446   143%     2547     159    151317180
+  filter=5,level=1   44203   145%  43805   148%      442     168    156934080
+  filter=1,level=9   44739   147%  42537   143%     2447     149    151714120
+  filter=1,level=5   43955   144%  43263   146%      769     150    154930330
+  filter=1,level=1   44605   147%  44292   149%      348     156    158763080
+pngcrush -q          49026   161%  42265   142%     7512     455    147813040
+pngcrush -brute     165325   545%  53632   181%   124103     460    146744530
+btpc  100            45618   150%  45209   152%      454     273    161606980
+lsp   -g             42530   140%  42119   142%      456     375    150115060
+lsp                  32507   107%  32034   108%      526     434    113570440
+locoe -N -c1         41544   137%  41271   139%      303     323    147305210
+locoe -N -c2         41732   137%  41406   140%      362     342    147701630
-PhotoJazz            ?????    ?    ?????    ?        ???     ???    111673670

+ indicates new lines in current volume of ARTest
- indicates oldest lines, that will not be present in next volume
* only because most files are identical, and RK *always* uses "solid" archiving

Overall score is calculated by adding compression time, extraction time, and
time it would take to transfer the compressed file over a 28,800bps network:
(compressed_size)/3600 , because 28800 bits_per_second is 3600 bytes_per_second

Average Users' score is calculated by adding (compress_time/10)+ extract_time +
time it would take to transfer the compressed file over a 28,800bps network.
Compression time is divided by 10 here, because more than 90% of people would
never compress anything during their life (with compression programs), but they
use compressed data almost _every_ time they use computers and/or Internet.
That's why compression time is not so actual for them.


[[3]] Details
=============
are no longer put to this main text
(380 lines reporting 10080 results on 336 files in 10 sets),
but can be found in FULL version with GRAPHICS.DAT and *.BAT
at http://geocities.com/SiliconValley/Bay/1995/artest19.zip
or http://artest1.tripod.com/artest19.zip

1,2,3,4,9 image sets were taken from ftp://ipl.rpi.edu/pub/image/ and /image2/
converted from Sun Raster format to Windows Bitmap,
(this conversion changes image headers only, 32 bytes
are replaced by 54 bytes, but image data is not modified)

This site ipl.rpi.edu is described in comp.compression FAQ by Jean-loup Gailly,
in 29 lines of "Subject: [55] Where can I find Lenna and other images?"

Eight images in the 5th set are from the famous Waterloo Color Set,
         ( losslessly compressed with Eri32 4.8fre to 2,893,654 bytes,
           it can be found at http://geocities.com/eri32 )
6,7,8th image sets are from  ftp://download.intel.com/pressroom/images/
10th set was downloaded from ftp://ftp.kodak.com/www/images/dental/
They were converted from TIFF format to Windows Bitmap.

Some images were slightly renamed. See GRAPHICS.DAT from artest19.zip for more
details. Some new images (from download.intel.com) were not added yet.


[[4]] Comments
==============
Links to download programs:
~~~~~~~~~~~~~~~~~~~~~~~~~~~
7-Zip  2.11   :W http://www.7-zip.com/dl/7zip211.exe                              493K
ArHanGeL 1.40 :a http://geocities.com/SiliconValley/Lab/6606/arh140.zip            50K
BMF    1.1    :e ftp://ftp.simtel.net/pub/simtelnet/win95/graphics/bmf_1_10.zip   132K
ERI32  4.7fre :e http://geocities.com/eri32/eri47fre.zip                           91K
Imp     1.1   :e http://www.winimp.com/imp110d.zip                                266K
Imp-win 1.12  :W http://www.winimp.com/imp112.exe                                 122K
PkZip   2.50  :a ftp://ftp.simtel.net/pub/simtelnet/msdos/arcers/pk250dos.exe     202K
PkZip32 2.50  :W ftp://ftp.simtel.net/pub/simtelnet/win95/compress/pk250c32.exe   300K
RK     1.02a5 :W http://malcolmt.tripod.com/downloads/rk102a05.exe                191K
RKim   1.06   :W http://malcolmt.tripod.com/downloads/rkim106.zip                  57K
RAR32  2.71   :e ftp://ftp.netlab.sk/public/rarsoft/rar/rarx271.exe               257K
WinRAR 2.71   :W ftp://ftp.netlab.sk/public/rarsoft/rar/wrar271.exe               588K
UHIC   1.0    :e ftp://ftp.elf.stuba.sk/pub/pc/pack/uhic10.zip                     52K
NK     Nov'99 :W ftp://tu.tusur.ru/pub/ImageTools/compress.zip                     81K
JPEG-LS 1.00  :W http://www.hpl.hp.com/loco/jlsrefV100.zip                        325K
PngCrush 1.5.1:e http://download.sourceforge.net/pmt/pngcrush-1.5.1-DOS.zip       143K
SPIHT  Nov'96 :W http://www.cipr.rpi.edu/research/SPIHT/EW_Code/lsp.exe            72K
BTPC   4.1    :W http://www.engr.mun.ca/~john/btpc4.1.zip                         715K
Display 1.90b5:e http://www.freenet.edmonton.ab.ca/~crnelson/disp.exe             811K
Alchemy 1.10  :a ftp://ftp.elf.stuba.sk/pub/pc/graph/alch110.zip                 1462K
SEA 1.3       :e ftp://ftp.elf.stuba.sk/pub/pc/graph/sea13.zip                    705K

:a - any DOS  - DOS programs, will run under pure DOS or in a DOS box
:e - extender - DOS programs using DOS extenders like DOS/4GW or CWSDPMI
:W - windoze  - Windows95/98/NT/etc programs

If direct link doesn't work-most probably newer version of the program appeared
at the same site: visit web page, or read the whole directory from ftp server
(i.e. try the same URL, but without filename).


Homepages:
~~~~~~~~~~
Arhangel     : http://geocities.com/SiliconValley/Lab/6606
Eri32        : http://geocities.com/eri32
      mirror : http://artest1.tripod.com
RK, RKim     : http://malcolmt.tripod.com
Imp,WinImp   : http://www.technelysium.com.au
      mirror : http://www.winimp.com
PkZip        : http://www.pkware.com
Ufa,777,7-Zip: http://www.7-zip.com
RAR,WinRAR   : http://www.rarsoft.com
JPEG-LS      : http://www.hpl.hp.com/loco
PngCrush     : http://pmt.sourceforge.net/pngcrush
SPIHT        : http://www.ipl.rpi.edu/research/SPIHT
BTPC         : http://www.engr.mun.ca/~john/btpc.html
Display      : http://fn2.freenet.edmonton.ab.ca/~crnelson/display.html
Alchemy      : http://www.handmadesw.com/Products/Image_Alchemy.htm
SEA          : http://www.photodex.com/products/dos


What's new:
~~~~~~~~~~~
PngCrush 1.5.1, ERI32 4.8fre, WinRAR 2.71, RAR32 for DOS and OS/2 2.71,
RK 1.03b1, ACE 2.00b3 and NK ver.1 were released.

They will be tested soon.
Results of Pngcrush 1.4.4, RK 1.02a5 and RAR 2.70 are given.


WARNINGS:
~~~~~~~~~
 ESP, Rkive and some other programs are not tested any more,
 their results and links can be found in previous versions:
 ESP   - artest3...artest12
 Rkive - 3...12
 UFA   - 3...12
 777   - 13...14
 BOA   - 7...14
 UHARC - 5...10
 CompuShow 2000! - 3...11

  ESP 1.92 has some bugs and was unable to correctly uncompress
  some test images: they are (re)named in our tests as
                AYMAR,GELSNGR,NACHTSH,OTELLIN,VADASZ,YASSO,YU1,
                DP08189,DP2179D,L217C-3,CONCEP3,PS09157,V42798C.
  ESP doesn't even report something like "CRC fails"...as if everything is OK.

   Rkive 1.92b1 fails to losslessly uncompress most images
   from 6th, 7th and 8th tests, and also Clegg, Frymire, Serrano from 5th.
   It reports
   ERROR: File fails CRC check!.
   Archive failed integrity check.

The LATEST RELEASE, and all previous versions of these tests can be found
at http://geocities.com/SiliconValley/Bay/1995/ and http://artest1.tripod.com/


The FINAL PART
==============
>     [[5]] PLEASE read THIS before replying to this article
was removed from this text, but can be easily found at
http://geocities.com/SiliconValley/Bay/1995/artest10.html
http://artest1.tripod.com/artest10.html

Send your suggestions, comments to artest@hotmail.ru
With best kind regards,
RAO Inc.
