[@ twey othala ] % wget http://testing.fatpromotions.com/thebeachpad/landing/images/pebbles.png
--2011-08-16 21:56:06--  http://testing.fatpromotions.com/thebeachpad/landing/images/pebbles.png
Resolving testing.fatpromotions.com... 83.138.147.91
Connecting to testing.fatpromotions.com|83.138.147.91|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 8318610 (7.9M) [image/png]
Saving to: `pebbles.png'

100%[=================================>] 8,318,610    845K/s   in 9.1s    

2011-08-16 21:56:15 (889 KB/s) - `pebbles.png' saved [8318610/8318610]

[@ twey othala ] % convert -flatten pebbles.png pebbles-flat.png
[@ twey othala ] % pngcrush pebbles-flat.png pebbles-flat-crushed.png

 | pngcrush 1.7.15
 |    Copyright (C) 1998-2002,2006-2011 Glenn Randers-Pehrson
 |    Portions copyright (C) 2005       Greg Roelofs
 | This is a free, open-source program.  Permission is irrevocably
 | granted to everyone to use this version of pngcrush without
 | payment of any fee.
 | Executable name is pngcrush
 | It was built with libpng version 1.5.2rc02, and is
 | running with  libpng version 1.5.2rc02 - March 22, 2011

 |    Copyright (C) 1998-2004, 2006-2011 Glenn Randers-Pehrson,
 |    Copyright (C) 1996, 1997 Andreas Dilger,
 |    Copyright (C) 1995, Guy Eric Schalnat, Group 42 Inc.,
 | and zlib version 1.2.5, Copyright (C) 1995-2010 (or later),
 |    Jean-loup Gailly and Mark Adler.
 | It was compiled with gcc version 4.6.1.

   Recompressing pebbles-flat.png
   Total length of data found in IDAT chunks    =  1746235
   IDAT length with method   1 (fm 0 zl 4 zs 0) =  1769066
   IDAT length with method   2 (fm 1 zl 4 zs 0) =  1614972
   IDAT length with method   3 (fm 5 zl 4 zs 1) =  1551832
   IDAT length with method   9 (fm 5 zl 2 zs 2) =  1595518
   IDAT length with method  10 (fm 5 zl 9 zs 1) =  1493934
   Best pngcrush method = 10 (fm 5 zl 9 zs 1) for pebbles-flat-crushed.png
     (14.45% IDAT reduction)
     (14.49% filesize reduction)

   CPU time used = 4.700 seconds (decoding 0.160,
          encoding 4.490, other 0.050 seconds)

[@ twey othala ] % convert pebbles.png pebbles.jpeg 
[@ twey othala ] % ls -lh
total 12M
-rw-r--r-- 1 twey twey 1.5M Aug 16 22:06 pebbles-flat-crushed.png
-rw-r--r-- 1 twey twey 1.7M Aug 16 22:06 pebbles-flat.png
-rw-r--r-- 1 twey twey 308K Aug 16 22:06 pebbles.jpeg
-rw-r--r-- 1 twey twey 8.0M Aug 15 17:18 pebbles.png
[@ twey othala ] % rm *
[@ twey othala ] % wget http://filedb.experts-exchange.com/incoming/2010/07_w29/325665/screenshot1.png -O screenshot.png
--2011-08-16 23:15:23--  http://filedb.experts-exchange.com/incoming/2010/07_w29/325665/screenshot1.png
Resolving filedb.experts-exchange.com... 64.156.132.195
Connecting to filedb.experts-exchange.com|64.156.132.195|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 404642 (395K) [image/png]
Saving to: `screenshot.png'

100%[=================================>] 404,642      213K/s   in 1.9s    

2011-08-16 23:15:25 (213 KB/s) - `screenshot.png' saved [404642/404642]

[@ twey othala ] % pngcrush screenshot{,-crushed}.png

 | pngcrush 1.7.15
 |    Copyright (C) 1998-2002,2006-2011 Glenn Randers-Pehrson
 |    Portions copyright (C) 2005       Greg Roelofs
 | This is a free, open-source program.  Permission is irrevocably
 | granted to everyone to use this version of pngcrush without
 | payment of any fee.
 | Executable name is pngcrush
 | It was built with libpng version 1.5.2rc02, and is
 | running with  libpng version 1.5.2rc02 - March 22, 2011

 |    Copyright (C) 1998-2004, 2006-2011 Glenn Randers-Pehrson,
 |    Copyright (C) 1996, 1997 Andreas Dilger,
 |    Copyright (C) 1995, Guy Eric Schalnat, Group 42 Inc.,
 | and zlib version 1.2.5, Copyright (C) 1995-2010 (or later),
 |    Jean-loup Gailly and Mark Adler.
 | It was compiled with gcc version 4.6.1.

   Recompressing screenshot.png
   Total length of data found in IDAT chunks    =   404463
   IDAT length with method   1 (fm 0 zl 4 zs 0) =   361049
   IDAT length with method   2 (fm 1 zl 4 zs 0) =   310432
   IDAT length with method   3 (fm 5 zl 4 zs 1) =   295755
   IDAT length with method   9 (fm 5 zl 2 zs 2) =   999446
   IDAT length with method  10 (fm 5 zl 9 zs 1) =   276902
   Best pngcrush method = 10 (fm 5 zl 9 zs 1) for screenshot-crushed.png
     (31.54% IDAT reduction)
     (31.54% filesize reduction)

   CPU time used = 2.120 seconds (decoding 0.090,
          encoding 2.020, other 0.010 seconds)

[@ twey othala ] % convert screenshot.{pn,jpe}g 
[@ twey othala ] % ls -lh
total 1000K
-rw-r--r-- 1 twey twey 271K Aug 16 23:15 screenshot-crushed.png
-rw-r--r-- 1 twey twey 329K Aug 16 23:16 screenshot.jpeg
-rw-r--r-- 1 twey twey 396K Jul 12  2010 screenshot.png