#include <StringConstants.au3> ; to declare the Constants of StringRegExp
#include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate
Local $sRegex = "(?s).*speed=\s*\K([\V]*)(?=x.*$)"
Local $sString = "frame=13920 fps= 86 q=-1.0 size= 96512kB time=00:07:44.47 bitrate=1702.2kbits/s speed=2.88x " & @CRLF & _
"frame=14068 fps= 87 q=-1.0 size= 98048kB time=00:07:49.41 bitrate=1711.1kbits/s speed= 2.9x " & @CRLF & _
"frame=14116 fps= 87 q=-1.0 Lsize= 98954kB time=00:07:51.06 bitrate=1720.9kbits/s speed=2.91x " & @CRLF & _
"video:86252kB audio:3826kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 9.852874%"
Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH)
Local $aFullArray[0]
For $i = 0 To UBound($aArray) -1
_ArrayConcatenate($aFullArray, $aArray[$i])
Next
$aArray = $aFullArray
; Present the entire match result
_ArrayDisplay($aArray, "Result")
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm