* lisp/image.el (image-type-header-regexps):
Allow two or more CRs or LFs in initial whitespace sequences. See:
http://netpbm.sourceforge.net/doc/pbm.html
(defconst image-type-header-regexps
`(("\\`/[\t\n\r ]*\\*.*XPM.\\*/" . xpm)
("\\`P[1-6]\\(?:\
-\\(?:\\(?:#[^\r\n]*[\r\n]\\)?[[:space:]]\\)+\
-\\(?:\\(?:#[^\r\n]*[\r\n]\\)?[0-9]\\)+\
+\\(?:\\(?:#[^\r\n]*[\r\n]\\)*[[:space:]]\\)+\
+\\(?:\\(?:#[^\r\n]*[\r\n]\\)*[0-9]\\)+\
\\)\\{2\\}" . pbm)
("\\`GIF8[79]a" . gif)
("\\`\x89PNG\r\n\x1a\n" . png)