Mike Scheidler <c23mts(a)eng.delcoelect.com&gt; writes: It can have. Cause PNG is the ability to add private tags, we could use this feature to add symbolic names to a palette. This will *not* break the png for 'standart' PNG libs/viewers/converters, but XEmacs (who will know those tags) can use them to change the colors. If you (and the others) are interested in such an addition, here is a short example how it will look like (I can also code this example, but first tell me if you and the others will accept such an addition): Each png image will have a standart PLTE (Palette; critical, public, unsafe to copy) chunk. This will define the colors of the png image. In addition there will be a syMN (Symbolic Names; uncritical, private, unsafe to copy) chunk which lists color names mapped to pallette indicies. If the docoder (XEmacs in our case) 'knows' syMn, he will try to change the symbolic colors. In the case the chunk is not known, a viewer will ignore it without a warning, but an editor which does not know it, will complain and don't copy it, cause the image may change if the palette is changed. A simple converter can do the job converting XPM to PNG and preserve the symbolic names, but it is also an easy task to write an 'Palette Symbolic Name Editor' which will give the 'programmer/painter' the ability to edit the symbolic names of the palette (this is no workaround, cause currently there is no drawing program which will let you edit such sym names -- you always have to use an editor to do the job). So we will have sym names and the advantage of having small image files in one format: PNG. Regards, Oliver.