I recently created some fireworks images/docs, these were made up of many layers and then exported as a png for use on a website. I ran pnggauntlet to compress these files but now I have returned to make some changes, it looks like now all of the layers have been converted into a bitmap background!
I really need to be able to edit my original document, please help?
Gary
counting_pine at
Re: Can I Undo PNGGAUNTLET ??
I think what Fireworks does is to store all its own layers information as metadata in ancillary chunks within the PNG file. The combined result of the layers, which is what you're seeing now, would have been stored as the image data of the PNG, allowing you to view the flat image in other PNG viewers/editors.
Normally, ancillary chunks don't contain important information, and PNGOUT removes them by default, as part of the filesize reduction process. PNGGauntlet probably has the same default settings, although it's probably changeable in Advanced Options.
Bad news though: once the file has been shrunk down, the chunks can't be recovered, unless you have a backup, or possibly if you spend a lot of money and send your hard disk to a data recovery centre.
It was possibly a bad choice, on Fireworks' part, to allow PNG to be used as a native file format. PNG's really not desinged for that sort of thing, and the file would be treated as a normal, flat PNG file by most programs, with no guarantee that it would retain the metadata after saving it. Does Fireworks allow full saving in any other format? If so, it might be best to use that instead of PNG, to avoid that sort of hazard...
EDIT: Wikipedia offers another description of the issue, here: http://en.wikipedia.org/wiki/Portable_Network_Graphics#Bitmap_graphics_editor_support_for_PNG