[Ffmpeg-devel-irc] ffmpeg.log.20140830

[burek]

[00:00] <ac_slater_>  klaxa: huh, I guess specifying two outputs is ok
[00:10] <ac_slater_> ls
[00:10] <ac_slater_> ;) oops
[01:48] <jorb> klaxa: thx for you help .. I did figure out that the only way some of the files would work is via the older Subsonic compiled version of ffmpeg.. where it just threw out the "video" stream for the album cover
[01:54] <jorb> pasted the other output .. not sure what release of ffmpeg the "no drop" transcode uses ... http://pastebin.com/Tf875r8E
[02:40] <wumzi> Hi. I've been trying to compile ffplay.c only from the latest development version of ffmpeg. I've been trying things like that http://pastebin.com/AbJhnYZx without success. I'm running Ubuntu 14.04 64bits. I'm a bit lost ... Building the whole project with the Ubuntu Compilation Guide works perfectly. Do you have any idea ?
[02:54] <editor24> Hey
[02:54] <editor24> Anyone here played around with x265 (HEVC)?
[02:57] <c_14> editor24: presumably several, what's your question?
[02:59] <c_14> wumzi: why not just ./configure [options]; make ffplay ?
[03:00] <editor24> c_14: a few questions, actually.  I'll start with mcdeint
[03:01] <editor24> I'm trying yadif and mcdeint to get from 30i DV to 30p HEVC MP4
[03:01] <editor24> is there a setting you can suggest?  I have yadif=1:1,mcdeint=0:1:10
[03:07] <c_14> Hmm, don't do much deinterlacing, but that should work. Anything wrong with it?
[03:19] <editor24> c_14: No, it worked well, afaik.  I got it from a forum, but without much explanation
[03:19] <editor24> Guess I'll keep it
[03:20] <editor24> Do you know what framestep=2 will do?
[03:21] <editor24> My full command:
[03:21] <editor24> ffmpeg.exe -v verbose -i test.avi -threads auto -sws_flags lanczos -vf "yadif=1:1,mcdeint=0:1:10,framestep=2,scale=iw*sar:ih,unsharp=3:3:2.03" -codec:v libx265 -b:v 1500k -minrate 1k -maxrate 128k -flags +loop -me_method umh -g 250 -qcomp 0.6 -qmin 01 -qmax 81 -qdiff 4 -bf 16 -b_strategy 4 -i_qfactor 0.81 -af "aresample=44100" -codec:alibvo_aacenc -b:a 128k -ac 2 -y test.mp4
[03:21] <c_14> afaik it will drop every other frame
[03:22] <c_14> or duplicate every frame
[03:22] <c_14> ehhh
[03:22] <c_14> https://ffmpeg.org/ffmpeg-filters.html#framestep
[03:22] <c_14> If whatever it says there is of any help to you.
[03:23] <c_14> You might not want to use libvo_aacenc, the native encoder is probably better
[03:23] <editor24> okay
[03:23] <c_14> See: https://trac.ffmpeg.org/wiki/Encode/AAC
[03:24] <editor24> what is it..?
[03:24] <c_14> An aac encoder.
[03:24] <editor24> i mean, how do i put it in the command line?
[03:24] <c_14> use -c:a aac -strict -2 instead of -c:a libvo_aacenc
[03:25] <editor24> thanks.  what's -strict -2?
[03:26] <c_14> The built in aac encoder is marked as experimental (although it's pretty stable) so you need to enable experimental encoders.
[03:27] <editor24> oh ok
[03:27] <editor24> any other thoughts about the command i pasted?  i just copied it ...
[03:30] <c_14> Nothing major, but a lot of those options are very specific. What you might want to do is adjust the video and audio bitrates.
[03:31] <c_14> The verbose loglevel might just spam you, and not sure if -threads auto does anything for x265
[03:31] <c_14> You'll also only need the audio filter if the sampling rate isn't already 44.1KHz (if you even want a sampling rate of 44.1KHz)
[03:32] <c_14> And if you want more than 2 audio channels (or less) you'll need to adjust the -ac option
[03:32] <c_14> You'll probably also want to get rid of the -y (so you don't accidentally overwrite existing files)
[03:34] <editor24> How do I add a mode to mcdeint?  The FFmpeg documentation says I can set it to fast, medium, slow, extra_slow.
[03:35] <c_14> mcdeint=mode=[mode]:parity=[parity]:qp=[quantization]
[03:36] <c_14> If you don't name the arguments, they are assumed to be in that order.
[03:36] <c_14> The {fast,medium,slow,extra_slow} names are probably mapped to numbers, but I don't know how.
[03:36] <c_14> In any way, if you want to force a setting just use the name.
[04:26] <editor24> hello
[04:27] <editor24> how do i change the mcdeint speed to extra_slow?
[06:08] <rule_2> I am trying to test capture functionality with a webcam before I use ffmpeg to record from an HDMI input card I plan on getting
[06:09] <rule_2> I tried recording from a webcam but I get unknown input format: 'vl42'
[06:09] <rule_2> if I run ffmpeg -list_formats all -f v4l2 -i /dev/video0 I get Unrecognized option 'list_formats
[06:10] <rule_2> am I looking at outdated documentation to try and use ffmpeg?
[06:22] <chriys> hi all
[06:23] <chriys> I'm looking to setup HLS live streaming from my camera. I'll send a signal using FMLE or Wirecast. The server will be on a vps (Ubuntu or Debian). Do you have a link for the steps to advise me ?
[07:29] <techtopia> hello
[07:29] <techtopia> i run this line
[07:29] <chriys> sup techtopia
[07:29] <techtopia> ffmpeg.exe -y -i %input01% -sws_flags spline -sn -vf yadif=1:0,crop=%width%:%height%:%left%:%top% -s 704x394 -c:v libx264 -preset slow -crf %crf% -r 50 01.mp4
[07:30] <techtopia> with no -acodec specified because a demux the audio and encode it seperatly
[07:30] <techtopia> but the encoded 01.mp4 still has the source audio file present
[07:31] <techtopia> is there soway to specify that i just want to encode the video and forget about the audio
[07:31] <techtopia> someway*
[07:32] <ghospich> -an
[07:32] <ghospich> maybe, if i understood correctly
[07:32] <techtopia> thanks, i will do a quick test :)
[07:35] <techtopia> it still has the audio track with -an
[07:36] <techtopia> ffmpeg.exe -y -i test.ts -sws_flags spline -sn -vf yadif=1:0,crop=720:576:0:0 -s 704x394 -c:v libx264 -preset slow -crf 21 -r 50 -an 01.mp4
[07:43] <ghospich> try something like "-map -0:a:0"
[07:44] <ghospich> also, position of argument matter, so try paste -an after -sn, not to the end.
[09:07] <vedos> howdy
[09:09] <vedos> i'm using youtube-dl to download stuff from Youtube... youtube-dl defaults to avconv, but can also use ffmpeg if i install it. which should i use to dump wav files out of the videos? which is more reliable and gives better sound quality?
[10:40] <techtopia> is there a way to use -concat so it will process all files in a directory
[10:40] <techtopia> instead of having to create a text file or an elaborate batch file
[11:22] <techtopia> http://pastebin.com/6qZDfjv0
[11:22] <techtopia> how can i get this to work
[11:22] <techtopia> atm it just asks for a yes or no response instead of asking for a number
[12:49] <wodim> please recommend me one of those modern shiny codecs that produce a good quality video in a small file.
[12:55] <techtopia> x264 and x265
[12:56] <techtopia> i use libx264 with ffmpeg
[12:56] <techtopia> quick encodes, decent filesize, good quality
[12:57] <techtopia> x265 will get you a smaller filesize for a comparable quality but takes longer to encode
[12:57] <Chaz6> vp8?
[12:59] <JEEB> vp8 is spec-wise close to baseline profile H.264, and the encoder is slow
[13:00] <JEEB> vp9 is better than high profile H.264 spec-wise but the encoder is even more slow
[13:00] <JEEB> (since it doesn't even have multithreading)
[13:09] <K4T> btw: better buycpu with more cores or higher frequency for ffmpeg?
[13:09] <K4T> I need to stream multiple streams with ffmpeg in real time
[13:10] <K4T> some of them I have to reencode
[13:56] <techtopia> im enocding from a transport stream and the resulting encodes have this menu text in them http://i.imgur.com/uYwt552.jpg
[13:56] <techtopia> this is my line "ffmpeg.exe -y -i 01.ts -sws_flags spline -sn -vf yadif=1:0,crop=720:576:0:0 -s 704x394 -c:v libx264 -preset slow -crf 21 -r 50 aaa.mp4"
[13:56] <techtopia> how can i omit the text from the encode
[13:57] <techtopia> without remuxing at the end
[14:18] <relaxed_> techtopia: add -map 0:v -map 0:a after the input
[15:17] <chriys> hi all
[15:20] <chriys> how can I make ffmpeg to grab a file sent from a rtmp server?
[15:21] <chriys> I'm going to send the feed from FMLE then it will go to red5 (rtmp server) then to ffmpeg, then to ffserver (this one will will HTTP serve the feed)?
[15:22] <chriys> I'm also interessed if there another way to grab the feed without passing by the rtmp server.
[15:30] <chriys_> how can I make ffmpeg to grab a file sent from a rtmp server?
[15:30] <chriys_> I'm going to send the feed from FMLE then it will go to red5 (rtmp server) then to ffmpeg, then to ffserver (this one will will HTTP serve the feed)?
[16:15] <c_14> ffmpeg -i rtmp://[server] [foobar]
[16:41] <Andy2> Hi guys, are asked this question what seems to be a bug a couple of days ago. http://ffmpeg.org/pipermail/ffmpeg-user/2014-August/023110.html
[16:41] <Andy2> I got some initial responses buit now nothing happens anymore.
[16:41] <Andy2> Can someone tell me how to proceed?
[16:41] <Andy2> Thanks
[17:54] <active8> Hi. I'm converting webm to mp4 using -q:v 0 (maybe 1 is the limit - I don't always get a warnig on that) and without any options I get pixelation on the output file. using -q:v 0 -c:v mpeg4 for an output specifier, it's ok. if ffmpeg guesses the codec, why would I need -c:v mpeg4 to get a good conversion. Also wondering if c:v copy is better than -q:v 0 .
[17:54] <Fjorgynn> I see
[17:55] <Fjorgynn> -c:v means that you don't reencode the file just copy the encodec
[17:55] <Fjorgynn> and you should probably use libx264
[17:56] <Fjorgynn> and -crf instead of -q:v 0 maybe
[17:56] <Fjorgynn> active8: but what do I know
[17:58] <active8> your first stmnt: -c:v means... you mean that -c:v copy means to just copy? does ffmpeg then pick a codec to make the mp4?
[17:59] <Fjorgynn> no I think it just copies it to another container
[17:59] <Fjorgynn> good if you want to remove video from audio or vice versa
[18:00] <active8> so vlc is trying to play an mp4 which is actually a webm stuck in an mp4 container and thus the pixelation?
[18:01] <Fjorgynn> ffmpeg -i test.webm -c:a copy -c:v libx264 -crf 22 test.mp4
[18:04] <active8> what is -crf
[18:04] <active8> ?
[18:05] <active8> looks like frame rate,but i thought that was just -r
[18:09] <JEEB> active8, x264 setting, constant rate factor. it is not (since we have no thousands of little brains in our PCs) constant quality level, but it's the closest we have to it
[18:09] <JEEB> 23 is the default, and higher values use compress more, lower values compress less. the idea is to find the highest value that still looks good
[18:10] <active8> oh. so codecs have options, too. man page didn't turn up anything on that. maybe there's a man (X) ffmpeg that does or a man libx264
[18:12] <JEEB> there was a way to output encoder-specific help with -help but don't ask me how :P
[18:12] <JEEB> never used that feature
[18:12] <JEEB> http://ffmpeg.org/ffmpeg-all.html contains some of the stuff
[18:15] <Fjorgynn> 0~0~
[18:15] <active8> grep didn't work for some reason, but ffmpeg --help | less and then /-crf <enter> took me there. Thanks JEEB and Fjorgynn
[18:18] <durandal_1707> ffmpeg -h encoder=libx264
[18:28] <active8> durandal_1707, what system are you using? encoder=libx264 doesn't do anything more here. I just get the same output as ffmpeg -h
[18:32] <active8> you want a pastie for what?
[18:33] <durandal_1707> output of ffmpeg
[18:33] <durandal_1707> anyway you are either not using ffmpeg or using very old version
[18:38] <active8> i compiled it maybe 6 mos to a year ago - oh... i was calling help on the one installed from a safe repository. I see the diff now when I run it with encoder=libx264 on the one I compiled myself - ffmpeg version git-2013-08-04-61af627
[18:39] <active8> that's a nice feature. specific help. thanks
[19:47] <anshul_mahe> please help me with some alternative of -list_devices true -f dshow to be used  when directly using libav library
[20:16] <TwisteR> Greetings! I need to embed an ass softsub to mkv file and set subtitle's 'default' flag to 1
[20:17] <TwisteR> here is my command line: ffmpeg -i in.mkv -c:v copy -c:a copy -metadata:s:s:0 language=eng -metadata:s:s:0 default-flag=1 out.mkv
[20:17] <TwisteR> tried also this: -metadata:s:s:0 disposition:default=1
[20:18] <klaxa> afaik ffmpeg does not support that yet
[20:18] <TwisteR> but ffprobe output tells me that those flags are in some incorrect place:
[20:18] <TwisteR> DISPOSITION:default=0
[20:19] <TwisteR> TAG:DISPOSITION:DEFAULT=1
[20:19] <klaxa> https://trac.ffmpeg.org/ticket/2402
[20:19] <TwisteR> klaxa: yep, that is my case, thanks
[20:20] <klaxa> you can try mkvmerge or mkvmerge-gui from mkvtoolnix instead
[20:20] <TwisteR> klaxa: thanks, I'll try them
[21:00] <tfirg_> i have a trivial and probably common question:
[21:01] <tfirg_> i have a ffmpeg x11grab line that cooks my laptop, and i am looking for ways to make it less intensive on my system while preserving reasonable quality
[21:01] <tfirg_> ffmpeg -f alsa -ac 2 -i pulse -f x11grab -r 30 -s 1366x768 -i :0.0 -acodec pcm_s16le -vcodec libx264 -preset ultrafast -crf 0 -threads 0 ${1}.mkv
[21:02] <tfirg_> that is what i have
[21:02] <tfirg_> so i tried less fps (15) and preset slow
[21:02] <tfirg_> but that still boils my cpu
[21:02] <c_14> That's cooking your laptop?
[21:02] <c_14> preset slow will make it use more cpu, btw
[21:03] <tfirg_> o ok
[21:03] <tfirg_> thats my i came here
[21:03] <tfirg_> for suggestions
[21:03] <c_14> If you have hard drive space to spare, you could just use rawvideo.
[21:03] <tfirg_> i want something that is light but still reasonable
[21:04] <tfirg_> but that needs to be processed sooner or later anyway
[21:04] <tfirg_> i have a 180 gig ssd in there but i was hoping for other suggestions
[21:04] <tfirg_> you know that example in man ffmpeg is nice an light
[21:04] <tfirg_> but its limited
[21:05] <tfirg_> no sound and i cant get it to do my resolution
[21:05] <tfirg_> so i was hoping for a middle ground
[21:07] <c_14> Maybe try one of the other lossless video codecs?
[21:07] <c_14> ffmpeg -codecs | grep ' .EV..S'
[21:10] <tfirg_> thanks, ill try, in the meantime if there are other suggestions, please let me know
[21:35] <klaxa> <c_14> If you have hard drive space to spare, you could just use rawvideo.
[21:35] <klaxa> that will pretty much fuck up I/O though
[22:11] <pixaal> hey folks - i'm converting an image sequence to a video (with audio as well) but it seems to ignore the '-r 24' framerate
[22:12] <pixaal> the audio is 5m 11s long, and there are 7485 frames which would make 5m 11s at 24fps, but the video finishes just before 5m while the audio carries on to 5:11
[22:16] <pixaal> the command is:   ffmpeg -i "02\img_%%04d.png" -i "02\audio.wav" -c:v libvpx -b:v 3M -c:a libvorbis -r 24 02.webm
[22:16] <pixaal> (double % to escape the % in a bat script on windows)
[22:20] <c_14> https://trac.ffmpeg.org/wiki/Create%20a%20video%20slideshow%20from%20images#Ifyourvideodoesnotshowtheframescorrectly
[22:21] <c_14> Try making your command look more like that (just with the added audio track and the codec/bitrate settings)
[22:21] <pixaal> will try, thanks
[23:26] <relaxed> pixaal: by default ffmpeg uses 25 fps with images as input- put -r 24 before -i "02\img_%%04d.png"
[23:27] Action: pixaal tries
[23:45] <pixaal> thanks relaxed, worked fine. i swear i tried that...
[23:45] <pixaal> o/
[00:00] --- Sun Aug 31 2014