J Decker wrote: >> How about the opposite direction: If m is base64 encoded to yield t >> and then t is base64 decoded to yield n, will it always be the case >> that m equals n? > > False. > Canonical translation may occur which the different base64 may be the > same sort of string...
Base64 is a binary-to-text encoding. Neither encoding nor decoding should presume any special knowledge of the meaning of the binary data, or do anything extra based on that presumption. Converting Unicode text to and from base64 should not perform any sort of Unicode normalization, convert between UTFs, insert or remove BOMs, etc. This is like saying that converting a JPEG image to and from base64 should not resize or rescale the image, change its color depth, convert it to another graphic format, etc. So I'd say "true" to Roger's question. I touched on this a little bit in UTN #14, from the standpoint of trying to improve compression by normalizing the Unicode text first. -- Doug Ewell | Thornton, CO, US | ewellic.org
