On Tue, Jun 6, 2017 at 11:49 AM, Michael Niedermayer <mich...@niedermayer.cc> wrote: > yes but its much harder to grep for as its not a single line anymore
I agree that it's not going to be as pretty a regular expression to grep through, as there is 33% more data, but it should still be doable without too much effort. How important is it that we maintain "API" compatibility on verbose CLI output? ffmpeg [...] scale2ref=0:0 [...] -v verbose - 2>&1 >/dev/null | grep -oP 'regex' Where regex is: (in|out|ref) +w:(\d+) h:(\d+) fmt:(\w+) sar:(\d+)\/(\d+)(?: flags:0x[[:xdigit:]]+)? Assuming GNU grep 2.25+, you'll get: in w:320 h:240 fmt:rgb24 sar:1/1 ref w:640 h:360 fmt:rgb24 sar:1/1 out w:640 h:360 fmt:rgb24 sar:3/4 flags:0x2 It also works with BSD grep 2.5.1-FreeBSD included in macOS if you use the -E option instead of -P. These would be considered three separate matches so if you're using a good regex engine it'd be pretty easy to loop over each match, check the first group to determine if it's in, ref, or out and act accordingly on the rest of the captured data. You could also, if you wanted, assume that the first line is in and the second line is out if you only have two matches (or lines even) and if you have three matches/lines the first is in, second is ref, third is out. If you needed it to work with less sophisticated engines it shouldn't be too hard to dumb down the regex above. Live-ish example: https://regex101.com/r/wvHLpa/1 Is there a special property that makes single lines much easier to grep? Something specific to bash? I wouldn't think bash would have any problems looping over this by line. Thanks, Kevin _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
