tag:blogger.com,1999:blog-1367102802658603789.post4486618364551915072..comments2024-01-29T04:29:03.583-08:00Comments on David Clunie's Blog: You're gonna need a bigger field (not) ... Radix 64 RevisitedDavid Cluniehttp://www.blogger.com/profile/17331067317921452126noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-1367102802658603789.post-67799711726790662952014-05-28T11:38:57.671-07:002014-05-28T11:38:57.671-07:00Forgot to consider, by the way, that leading and t...Forgot to consider, by the way, that leading and trailing spaces are not significant in a DICOM VR, so one needs to use a representation that does not include the space character (93 characters except a space and backslash).David Cluniehttps://www.blogger.com/profile/17331067317921452126noreply@blogger.comtag:blogger.com,1999:blog-1367102802658603789.post-43563893129606103592013-09-30T02:42:34.684-07:002013-09-30T02:42:34.684-07:00Fixed bad link in previous comment response ...
T...Fixed bad link in previous comment response ...<br /><br />Thanks for pointing that out ... there is a summary on <a href="https://en.wikipedia.org/wiki/Ascii85" rel="nofollow">this wiki page on Ascii85</a>, which makes reference to another helpful wiki page on <a href="https://en.wikipedia.org/wiki/Binary-to-text_encoding" rel="nofollow">Binary-to-text encoding</a>.<br /><br />Ascii85 uses the backslash character in its representation, which is a problem. The <a href="https://tools.ietf.org/html/rfc1924" rel="nofollow">RFC1924</a> variant does not use a backslash though, and could work.<br /><br />Using a radix of 85 doesn't seem to offer that much of a length advantage over using a radix of 64 (i.e., a 64 bit integer does fit in 10 rather than 11 characters, but an 18 digit decimal number uses 10 either way), and the choice of 85 to make 4 input bytes map to exactly 5 output bytes is not really a factor in our use case.<br /><br />Anyway, good to know that there are yet more choices :)David Cluniehttps://www.blogger.com/profile/17331067317921452126noreply@blogger.comtag:blogger.com,1999:blog-1367102802658603789.post-4669096332452358422013-09-30T02:34:33.695-07:002013-09-30T02:34:33.695-07:00This comment has been removed by the author.David Cluniehttps://www.blogger.com/profile/17331067317921452126noreply@blogger.comtag:blogger.com,1999:blog-1367102802658603789.post-50804279589681101902013-09-29T23:08:43.033-07:002013-09-29T23:08:43.033-07:00Interesting discussion. You're missing the ASC...Interesting discussion. You're missing the ASCII85 (Base 85) encoding that is widely used within the PostScript language and uses 85 different characters to represent 6.5 bits per character (4 bytes are encoded as 5 characters). <br />Anonymousnoreply@blogger.com