Enable lossless editing of PNGs via a textual representation.
copied from cf-staging / sngSNG (Scriptable Network Graphics) is a minilanguage designed specifically to represent the entire contents of a PNG (Portable Network Graphics) file in an editable form. Thus, SNGs representing elaborate graphics images and ancillary chunk data can be readily generated or modified using only text tools.
SNG is implemented by a compiler/decompiler called sng that losslessly translates between SNG and PNG.
