Why is it that png files are not dependable over the long haul

When PNG was created I enthusiatically preserved the majority of my
family pictures as PNG files and they were lost because of bugs in the
PNG libraries that were fixed.  I wrote aps to try to fix them as the
stock optpng etc all could not fix them. 

Now this month we lost a whole new set of precious images to some change
int he PNG libraries.

Images like this:

http://www.mrbrklyn.com/brooklyn/images/wall_art_river_and_metropolitian_avenue_williamsburg_2006_00578.png

which is completely mangles in the gimp and imagemagik but viewaable in
firefox?!?

What are you guys doing.  I am going to have no choice but to abandon
PNG.

-- 
So many immigrant groups have swept through our town
that Brooklyn, like Atlantis, reaches mythological
proportions in the mind of the world - RI Safir 1998
http://www.mrbrklyn.com 

DRM is THEFT - We are the STAKEHOLDERS - RI Safir 2002
http://www.nylxs.com - Leadership Development in Free Software
http://www2.mrbrklyn.com/resources - Unpublished Archive 
http://www.coinhangout.com - coins!
http://www.brooklyn-living.com 

Being so tracked is for FARM ANIMALS and and extermination camps, 
but incompatible with living as a free human being. -RI Safir 2013


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