For the fun
#Include <Array.au3>
$txt = "Objects (id: bounding-box centroid area mean-color):" & @crlf & _
" 0: 280x80+0+0 140.8,39.4 20069 gray(0)" & @crlf & _
" 4: 25x27+136+26 148.4,38.9 342 gray(255)" & @crlf & _
" 5: 25x26+34+27 48.9,39.9 307 gray(255)" & @crlf & _
" " & @crlf & _
" 6: 26x25+65+27 77.5,39.3 292 gray(255)" & @crlf & _
" 11: 33x18+211+34 227.7,41.3 289 gray(255)" & @crlf & _
" 9: 23x26+111+34 122.1,44.3 254 gray(255)" & @crlf & _
"" & @crlf & _
" 7: 16x19+70+30 77.8,39.0 219 gray(0)" & @crlf & _
" 2: 25x27+163+25 172.0,36.5 199 gray(255)" & @crlf & _
" 10: 20x18+187+34 197.2,41.6 179 gray(255)" & @crlf & _
" 3: 15x26+95+26 101.2,37.1 153 gray(255)" & @crlf & _
" 13: 11x11+116+37 121.1,42.2 97 gray(0)"
$txt = StringRegExpReplace($txt, '(^.+\R)|(?m)^(\s*\R)|(.*gray\(0\)\R?)', "")
$stmp = Execute("'" & StringRegExpReplace($txt, "(?m)(^.*?)(?<=\h)(\d+)(?=\.)", "' & StringFormat('%04i', '$2') & ' $1$2' & '") & "'")
$atmp = StringRegExp($stmp, '\N+', 3)
_ArraySort($atmp, 1)
$res = StringRegExpReplace(_ArrayToString($atmp, @crlf), '(?m)^\d{4}\h*', "")
Msgbox(0,"", $res)