[Ffmpeg-devel-irc] ffmpeg.log.20120909

burek burek021 at gmail.com
Mon Sep 10 02:05:01 CEST 2012


[00:16] <njbair> where can I find options for the deshake filter? Can't find them anywhere.
[01:26] <erre> helllo everyone
[01:30] <erre> i have a quick question - how i can stop capture after 1 minute??
[01:42] <erre> someone here in this time?
[01:42] <ubitux> -t 60
[01:43] <ubitux> njbair: https://ffmpeg.org/ffmpeg.html#deshake
[01:44] <erre> what "-t 60" mean?
[01:44] <ubitux> duration 60 seconds
[01:45] <erre> only to add "-t 60" to the command?
[01:45] <erre> I'm new in ffmpeg...
[01:50] <erre> ubitux: thanks - work grate!
[01:56] <erre> I'm try to do something like a "buffer" that keep 10 seconds of video, and when it will get trigger it will tage the 10 seconds from the  "buffer" and add to them 10  seconds from the trigger ... onward - at the end of the story i need to get 20 seconds of video file..
[01:59] <erre> there is something like that in ffmpeg -  or i need to take a looong video and cut it to 20 seconds video in the right time (10 before and 10 after the trigger)
[02:01] <ubitux> i didn't understand a word of what you are saying
[02:03] <erre> i want to catch somting fast in my camera..
[02:05] <erre> if i will start to capture from the "trigger time" i will lose the start and i get only "half of the video"..
[02:09] <erre> what i trying to do, is to make someting like a "buffer" that keep only the last 10 seconds of the live video.. and when it get trigger it take the 10 seconds from the "buffer" and add them to another 10 seconds.. so at the end i get 20 seconds of video file
[02:09] <erre> ubitux: ^
[02:10] <ubitux> you might need to do that with a filter
[02:10] <ubitux> if i understand you well
[02:13] <erre> how i do it with filter?
[02:15] <ubitux> write code
[02:16] <ubitux> but well by re-reading what you wrote i think i misunderstood the purpose
[02:16] <ubitux> why are you willing to buffer by 10 seconds?
[02:21] <erre> ubitux: lat's say that you want to take a video of braking glass with an arrow... but you get the trigger for the camera from the sound of the broken glass..  if you start to take the video in this point you will lose the arrow stroke - this is the reason that i want to keep 10 seconds before the trigger
[02:22] <ubitux> how would you integrate your trigger with ffmpeg?
[02:23] <ubitux> interactive?
[02:23] <ubitux> (manual event you would send)
[02:24] <erre> run the command from script that connect to a sensor
[02:27] <ubitux> what you make ffmpeg stop?
[02:27] <erre> is case like glass is easy  - but if you try to catch a lightning...
[02:30] <erre> i think to take thousands of 1 min videos.. every 30 sec end record the time of the trigger.. and after that extract it from one of the videos..
[02:32] <erre> but if there is better option i will happy to know..
[02:32] <ubitux> maybe the segmenter could be
[02:32] <ubitux> but i really have hard time trying to get how you will achieve that
[02:33] <ubitux> but that's likely because i'm tires
[02:33] <ubitux> -s+d
[02:33] <erre> what is segmenter?
[02:35] <ubitux> https://ffmpeg.org/ffmpeg.html#segment_002c-stream_005fsegment_002c-ssegment
[02:39] <erre> so.. i need to make like 10 sec of segment and it will be the "buffer"?
[02:53] <erre> someone here in this time?
[03:45] <lakcaj> Hi.  I'm trying to checkout a specific revision of ffmpeg to try to get playback of my security camera without artifacts.  However, when I perform the svn checkout, I get "svn: warning: URL 'svn://svn.ffmpeg.org/mplayer/trunk/libswscale' at revision 35157 doesn't exist".  Not sure what to make of that.
[12:49] <Yagger> Hello. I would like to request a change on the Wiki page for ffmpeg. Specifically the link about "Compiling to a Ramdisk" on MacOSX. The guide shown there is a ripoff from my blog posting (and not being maintained). It would probably be better if you used the "original". To whom can I forward the "correct" URL?
[12:50] <cbreak> if it's a wiki, can't you just change it?
[12:50] <Yagger> No. It requires a login as far as I can tell.
[12:51] <Yagger> I did want to avoid creating a login just for that change...
[12:52] <erre> hii it's me again..
[12:55] <erre> when i tryid to capture my camera with 2 FFMPEG command on 2 terminals.. one FFMPEG work grate and get the video, but the other get tish error/dev/video0: Input/output error
[12:56] <Yagger> I will create an account and change it.
[13:28] <relaxed> erre: pastie.org the command and all output
[13:29] <erre> ffmpeg -f video4linux2 -r 25 -s 640x480 -i /dev/video0 out.avi
[13:30] <erre> in one terminal -  work fine. at the second i get this error
[13:30] <erre> [video4linux2 @ 0x9171aa0] Cannot find a proper format for codec_id 0, pix_fmt -1. /dev/video0: Input/output error
[13:34] <erre> relaxed: ^
[13:44] <relaxed> what part of "pastie.org the command and all output" don't you understand?
[13:45] <relaxed> because what I asked for is pretty clear and specific
[13:46] <erre> relaxed: I'm new to this stuff.. in the next time i will do it.
[13:46] <relaxed> you'll do it this time or I will not help you.
[13:49] <erre> relaxed: i think i need to do something like "Circular Buffer"
[13:54] <erre> relaxed: and store the last 10 sec. in this circular buffer
[14:22] <killown> any opensuse user here? I just want confirm a ffmpeg bug
[14:22] <relaxed> what bug?
[15:36] <burek> if you want help, of course
[16:37] <fling> hello
[16:37] <fling> [alsa @ 0x1504380] cannot set sample format 0x10000 2 (Invalid argument)
[16:37] <fling> http://dpaste.com/798542/
[16:37] <fling> what am I doing wrong?
[16:38] <fling> relaxed: hey :p
[16:39] <fling> burek: hello
[16:40] <burek> hi :)
[16:41] <relaxed> fling: does this work? ffmpeg -f alsa -i hw:0 -t 10 -f wav ->/dev/null
[16:41] <fling> burek: http://dpaste.com/798542/
[16:42] <fling> relaxed: same > http://dpaste.com/798544/
[16:42] <burek> fling what is that?
[16:42] <burek> where is the console output?
[16:43] <fling> burek: sorry, here is it > http://dpaste.com/798548/
[16:44] <burek> that's not the output of what you gave
[16:44] <burek> (as a command)
[16:44] <burek> can you add -report to the command line
[16:45] <fling> burek: should be it! > http://dpaste.com/798550/
[16:46] <fling> ffmpeg-20120909-214543.log > http://bpaste.net/show/44598/
[16:46] <burek> hm.. can you try updating your ffmpeg?
[16:47] <fling> burek: tried, http://lists.ffmpeg.org/pipermail/ffmpeg-devel-irc/2012-January/000450.html
[16:47] <fling> still have this error :p
[16:47] <fling> also it works fine with hd1 (my webcam)
[16:47] <fling> s/hd1/hw:1/
[16:48] <fling> but I want to capture my soundcard
[16:48] <burek> what does that irc log show actually?
[16:48] <burek> what should I read there?
[16:49] <fling> burek: same error I had in the past, nothing changes with every update :[
[16:49] <burek> well your ffmpeg is old
[16:49] <burek> that might have been a bug which was fixed
[16:50] <burek> we can't know until you try the lates
[16:50] <burek> t
[16:50] <fling> ok
[16:51] <burek> btw, try this: ffmpeg -f alsa -ac 1 -sample_fmt s16 -i hw:0 ...
[16:51] <burek> it might help.. I'm not sure
[16:52] <burek> also ffmpeg -sample_fmts
[16:58] <fling> burek: Receiving objects:   2% (1129/46329), 276.00 KiB | 4 KiB/s
[16:58] <burek> your internet connection is awesome :)
[16:58] <fling> it will take a long time :p I will capture from a webcam while it is fetching :p
[16:59] <burek> try that sample_fmt trick
[16:59] <fling> burek: is 0.11.1 recent enough?
[16:59] <burek> and change values to see if one works
[16:59] <fling> http://dpaste.com/798558/
[16:59] <burek> I would use latest git
[16:59] <burek> try s32
[16:59] <burek> u8
[16:59] <burek> etc
[16:59] <fling> ok
[17:00] <burek> you have a list by typing ffmpeg -sample_fmts
[17:00] <burek> try if any of those work
[17:01] <fling> same error for every of 10 formats
[17:01] <fling> skype is capturing somehow and other apps too
[17:02] <fling> even Left 4 Dead :p
[17:02] <burek> can you type: arecord -L > out.txt
[17:02] <fling> http://bpaste.net/show/44602/
[17:04] <burek> try -i default:CARD=M1010LT instead of -i hw:0
[17:05] <fling> burek: http://dpaste.com/798560/
[17:06] <burek> does it work ok now?
[17:06] <fling> no
[17:06] <burek> how come
[17:06] <fling> [avi @ 0x1cf1770] Application provided invalid, non monotonically increasing dts to muxer in stream 1: 39 >= 39
[17:06] <fling> av_interleaved_write_frame(): Invalid argument
[17:06] <smt> relaxed: any suggestions?
[17:07] <relaxed> your ffmpeg version is too old
[17:07] <fling> also after upgrading to ffmpeg 0.7 I have a lot of these things > [alsa @ 0x1cf0380] ALSA buffer xrun.
[17:08] Action: fling is capturing from a webcam now
[17:08] <burek> how is "upgrading" from 0.10 to 0.7 actually an upgrade? :)
[17:08] <relaxed> smt: you can try -vf in place of -filter:v
[17:08] <fling> burek: a long in the past from 0.69 to 0.70
[17:08] <burek> btw fling, try without video, to see if your audio works first
[17:08] <burek> don't mix several issues at onace
[17:08] <burek> once*
[17:09] <burek> or you'll have a hard time debugging them
[17:09] <fling> burek: and I still have this xruns with every upgrade
[17:09] <smt> relaxed: that dowsnt work either
[17:09] <fling> burek: ok, will debug next week!
[17:10] <burek> ok
[17:10] <smt> relaxed, do u know any ppa with a more recent version? i dont wanne compile it by myself
[17:10] <burek> smt why not
[17:11] <fling> burek: how can I pipe one of the outputs to mplayer?
[17:11] <relaxed> smt: `uname -r -m` output?
[17:11] <burek> ffmpeg ... | mplayer .. ?
[17:11] <fling> umm
[17:11] <smt> 2.6.32-42-generic x86_64
[17:11] <relaxed> smt: http://dl.dropbox.com/u/24633983/ffmpeg/index.html
[17:12] <fling> burek: so I just replace &rtmp://10.2/rtmp/test.flv with &| mplayer ?
[17:12] <burek> fling, it's not that easy
[17:12] <burek> flv might or might not be streamable
[17:12] <burek> why do you need the pipe in the first place
[17:12] <smt> thanks relaxed, ill try that
[17:12] <burek> what can mplayer do that ffmpeg can't
[17:13] <fling> burek: because my erlyvideo is not working somewhy
[17:13] <fling> burek: but I want to monitor what I'm capturing
[17:14] <burek> fling "ffplay -f alsa -ac 1 default:CARD=M1010LT" or "ffplay -f video4linux2 -s 864x480 -r 15 /dev/video0"
[17:16] <fling> burek: but I want to record to a file same time
[17:16] <fling> this is how I made it in the past
[17:16] <fling> first stream goes to a file ; second goes to erlyvideo over rtmp
[17:19] <burek> well, with the latest ffmpeg that is possible
[17:19] <burek> I've seen a lot of people here talking about that recently
[17:19] <fling> it works even with old ffmpeg :P but my erlyvideo is broken
[17:19] <burek> so, you might want to first update your ffmpeg and then try?
[17:20] <burek> to avoid unnecessairy wasting of time debugging something that's solved now
[17:20] <fling> so I want to replace that rtmp streaw with a pipe&
[17:20] <fling> distcc[7921] ERROR: compile /var/cache/ccache/tmp/mpegaudiod.tmp.studio.7337.i on localhost failed
[17:21] <burek> http://ffmpeg.org/ffmpeg.html#pipe
[17:21] <burek> fling, you can use static ffmpeg if you don't know how to properly compile your own
[17:21] <burek> but I don't know if there is rtmp support for it
[17:22] <burek> or read the wiki to learn how to compile ffmpeg
[17:22] <burek> shouldn't be that hard
[17:22] <fling> gentoo here, I'm compiling everything
[17:23] <fling> if it moves compile it
[17:23] <burek> why gentoo then?
[17:24] <burek> if you are not very familiar with compiling, I mean
[17:24] <burek> why make more mess than needed?
[17:26] <smt> relaxed, that seems to work, thanks a lot
[17:27] <relaxed> you're welcome
[17:28] <robertzaccour> when I screencast the audio and video are out of sync. Any suggestions?
[17:28] <robertzaccour> this is what I paste to record ffmpeg -f alsa -i pulse -f x11grab -s 1920x1068 -r 60 -i :0.0 -sameq output.avi
[17:28] <robertzaccour> oops
[17:28] <robertzaccour> ffmpeg -f alsa -i pulse -f x11grab -s 1920x1080 -r 60 -i :0.0 -sameq output.avi
[17:30] <relaxed> try -r 30 and never use -sameq again.
[17:30] <burek> :D
[17:30] <smt> hmpf but it doesnt work on wmv files
[17:30] <burek> maybe there should be added a question "Are you sure you want to use -sameq option?" whenever that option is used :)
[17:30] <relaxed> it should, pastie.org the output
[17:31] <relaxed> smt: ^^
[17:31] <robertzaccour> relaxed, what do I use instead of -sameq?
[17:34] <relaxed> robertzaccour: -c:v libx264 -preset ultrafast -crf 0 -threads 0 -c:a pcm_s16le output.mkv
[17:34] <burek> robertzaccour, out of curiosity, what did you expect -sameq to do at the output?
[17:35] <relaxed> everyone thinks the q equals quality, you know this.
[17:36] <robertzaccour> didn't really think about it haha
[17:36] <smt> relaxed: when i change the width to a fixed value that is devidable by 2 it works, any ideas why?
[17:40] <relaxed> smt: what is the input's frame size?
[17:40] <robertzaccour> relaxed, still out of sync
[17:41] <smt> relaxed: 1280 x 720
[17:41] <smt> but even if i set it to 853:480 it doesnt work, if i set to 852:480 it works
[17:44] <Mavrik> smt, 4:2:0 video size has to be divisible by 2
[17:44] <Mavrik> you can't encode those otherwise
[17:45] <smt> hmm, but why does it work with mencoder?
[17:45] <Mavrik> either mencoder corrects the video size
[17:45] <Mavrik> or it encodes to a different pixel format
[17:48] <smt> bbl
[17:48] <robertzaccour> Maybe my hardware don't agree with ffmpeg haha but its a gaming pc I didn't think that was possible
[18:21] <seblabel> hey people
[18:22] <seblabel> i have a HD video of around 3go and i would like to put it on a dvd
[18:22] <seblabel> i need to convert the .avi into a mpeg2 file
[18:23] <seblabel> using : ffmpeg -i myinput.avi -target pal-dvd myoutput.mpg
[18:23] <seblabel> i got a 6go file
[18:23] <seblabel> it's by far to much for a dvd
[18:24] <seblabel> so, i need (well that's what i'm thinking) , i need to do a multipass process in order to get a good sized file (±4300mo)
[18:25] <seblabel> i don't know how to do that with ffmpeg, and looking at the documentation is really tricky.
[18:25] <seblabel> Does somedy already manage with this kind of process ?
[18:26] <seblabel> (i try to used avidemux for this purpose but all i got was a file with no sound...)
[18:26] <seblabel> i guess avidemux gives me an decoder while i needed a encoder
[18:27] <seblabel> thanks for the help you could give me
[18:30] <relaxed> seblabel: you need two pass encoding to hit a specific size
[18:34] <Mavrik> yeah, and you need to explicitly set output bitrate
[18:37] <seblabel> Mavrik: why do i have to specify the output bitrate if i already gave a final wanted size ?
[18:39] <seblabel> Did you already write a multipass line with ffmpeg ? maybe you still have it in your command line history ?? :)
[18:39] <JEEB> you only set that you wanted it to go within PAL DVD limitations (maximum bitrate within some buffer, probably the best bitrate you can get away with it)
[18:39] <Mavrik> seblabel, you never did give "final wanted size"
[18:39] <JEEB> at least looking at that one command line you posted
[18:40] <Mavrik> (-target pal-dvd doesn't do that)
[18:41] <JEEB> and then it sets the resolution and some other stuff, yeah -- so it generally fits within the specifications of a DVD
[18:42] <JEEB> you've never told it that you're limited to a single platter and that your length is too long for it to fit with the maximum possible bit rate
[18:42] <JEEB> you're going to have to override it
[18:44] <seblabel> my dvd can admit 4.6 go
[18:44] <seblabel> i would like to filled it totally to keep the video quality up the the maximum
[18:45] <cbreak> maximum?
[18:45] <cbreak> lossless.
[18:45] <JEEB> well, you'll have to basically calculate the bitrate needed to keep within that limitation :)
[18:46] <JEEB> take in count audio too, give it some container leeway and that's it
[18:46] <cbreak> you should settle for a "reasonable" quality
[18:46] <seblabel> i was meaning that the video that i have , a HD video in mp4 container (not avi) is a really good quality video and sized 3.0go
[18:47] <seblabel> JEEB: in this way, this is not a multipass process
[18:47] <seblabel> is it ?
[18:48] <cbreak> finding a bitrate is just calculating
[18:48] <cbreak> encoding a movie to fit into that bitrate is multi pass
[18:48] <cbreak> unless you are happy with a significantly uneven quality
[18:49] <seblabel> cbreak, do you have an idea of a command line that will do ?
[18:49] <cbreak> not with ffmpeg, sorry
[18:49] <seblabel> :D
[18:49] <seblabel> with mencoder ?
[18:49] <cbreak> if you have a hard bandwidth goal, you'll probably want to use h.264, so x264
[18:49] <JEEB> http://ffmpeg.org/ffmpeg.html -pass[:stream_specifier] n (output,per-stream)
[18:49] <cbreak> with two pass encoding
[18:50] <JEEB> cbreak, he wants to make a DVD
[18:50] <cbreak> or more than two :)
[18:50] <cbreak> oh
[18:50] <cbreak> an actual video dvd?
[18:50] <seblabel> cbreak: yes sir
[18:50] <cbreak> DVDs don't support HD
[18:50] <cbreak> they don't support mpeg 4
[18:50] <cbreak> so you'll end up with anything but maximum quality
[18:50] <seblabel> mpeg2 is quite good in quality
[18:50] <cbreak> quite a bit worse than mpeg4 :)
[18:51] <cbreak> just look at the number in the name, it's twice as big in mpeg4!
[18:51] <seblabel> i know that conversion gives a loose
[18:54] <Klaus_Dieter> hello world
[18:54] <JEEB> cbreak, he was using -target pal-dvd so it should take care of vbv/resolution and formats methinks
[18:55] <cbreak> no clue.
[18:55] <cbreak> I only know the theory
[18:55] <Klaus_Dieter> I used to use this command  for converting the video stream of a vob file to a raw 264 video but it does not work any more (unrecognized optione vpre)
[18:55] <Klaus_Dieter> avconv -y -i $input -vf crop=${crop[$track]} -b 2M -bt 4M -vcodec libx264 -pass 1 -pre fastfirstpass -an ${tempdir}/track${track}/movie.264
[18:55] <Klaus_Dieter> so I did change -vpre to -pre however I now get that avconv does not know which format to write the output file in
[18:56] <JEEB> Klaus_Dieter, x264's presets are now available via -preset
[18:56] <JEEB> also what was -bt?
[18:56] <JEEB> I know b
[18:56] <Mavrik> bitrate delta IIRC
[18:56] <JEEB> sounds like one needs -maxrate and -bufsize
[18:56] <Mavrik> Set video bitrate tolerance (in bits/s). In 1-pass mode, bitrate tolerance specifies how far ratecontrol is willing to deviate from the target average bitrate value. This is not related to min/max bitrate. Lowering tolerance too much has an adverse effect on quality.
[18:57] <JEEB> hmm
[18:57] <Mavrik> I'm pretty sure x264 ignores that parameter though
[18:57] <JEEB> yeah
[18:57] <Klaus_Dieter> how can I see which presets are available? fastfirstpass seems not to be possible either x264 [error]: invalid preset 'fastfirstpass'
[18:57] <Mavrik> Klaus_Dieter, I've written a guide on how to encode x264 with new parameters, I suggest you go read it: https://www.virag.si/2012/01/web-video-encoding-tutorial-with-ffmpeg-0-9/
[18:57] <JEEB> yes, fast first pass is automatically used with -pass 1 internally in libx264
[18:57] <JEEB> a list of presets can be found @ http://mewiki.project357.com/wiki/X264_Settings#preset
[18:58] <JEEB> the only preset that doesn't have  fast first pass by default is placebo
[18:58] <JEEB> everything else has
[18:58] <Klaus_Dieter> ah JEEB  so this is not needed any more?
[18:58] <JEEB> yup
[18:58] <JEEB> libx264 does it by itself
[18:58] <Mavrik> mhm
[18:58] <Klaus_Dieter> great!
[18:58] <Klaus_Dieter> ok thanks.
[18:59] <Klaus_Dieter> so what do I do about the format issue? Unable to find a suitable output format for 'movie.264'
[18:59] <Klaus_Dieter> I tried -f mpegts
[18:59] <Mavrik> Klaus_Dieter, ffmpeg can't detect container, since "264" is a non-standard extension
[18:59] <Klaus_Dieter> Mavrik:  I do not want to have any container
[18:59] <Klaus_Dieter> muxing is separate
[18:59] <JEEB>  DE h264            raw H.264 video
[18:59] <JEEB> -f h264
[19:00] <Mavrik> that.
[19:00] <Mavrik> :)
[19:00] <Klaus_Dieter> (multiple audio files
[19:00] <Klaus_Dieter> cool
[19:00] <Klaus_Dieter> JEEB: again - this is not in the manpage... :(
[19:00] <Mavrik> Klaus_Dieter, "ffmpeg -formats" gives you that
[19:00] <JEEB> avconv -formats, in his case :)
[19:00] <Klaus_Dieter> ah
[19:00] <Klaus_Dieter> hmm
[19:00] <Klaus_Dieter> thank you again for this help - avconv -y -i movie.vob -b 2M -bt 4M -vcodec libx264 -pass 1  -f h264 -an movie.264 seem to sork
[19:01] <JEEB> Klaus_Dieter, feel free to poke the libav bugzilla for that, although I guess it depends on the package managers :)
[19:01] <Mavrik> since supported formats (and codecs) change depending on how your ffmpeg was compiled
[19:01] <JEEB> I'm really not sure about -bt tho :D
[19:01] <Klaus_Dieter> yeah, it is difficult to keep up with all the changes
[19:01] <Klaus_Dieter> I have this one video conversion script and everytime I use it I have to alter the encoder options
[19:02] <JEEB> well, I don't see really big changes in the last 3-6 months
[19:02] <Klaus_Dieter> maybe it is older ;)
[19:02] <JEEB> but yeah, changes occur
[19:03] <JEEB> also, why are you using 1pass bitrate output with fast firstpass?
[19:03] <JEEB> just asking
[19:03] <JEEB> unless it's just temporary and you might just /dev/null it
[19:04] <Klaus_Dieter> probably because I have no idea what I am doing ;()
[19:04] <Klaus_Dieter> is this unreasonable?
[19:04] <seblabel> so, i just made an experiment on a piece of the file. This piece is 5 minutes long
[19:05] <JEEB> Klaus_Dieter, if you're actually going to use the output and you want just one pass I recommend just using a fast enough preset and crf rate control (esp. if you really don't care about exactly hitting some size/bitrate limit)
[19:06] <seblabel> and the original video is 132minutes long
[19:06] <JEEB> (-preset medium is the default btw)
[19:06] <Klaus_Dieter> I do not care about a specific bitrate but about a pretty good quality
[19:06] <JEEB> ok, then crf is just for you
[19:06] <Klaus_Dieter> what exactly does crf do?
[19:06] <JEEB> it's the closest to the theoretical "constant quality" we have at the moment
[19:06] <JEEB> (it really isn't, but it's the closest thing around for that)
[19:07] <Klaus_Dieter> so I should use crf with 2 passes?
[19:07] <JEEB> nope
[19:07] <JEEB> only one pass needed because it's a rate factor set to constant
[19:07] <Klaus_Dieter> ok
[19:07] <JEEB> 2pass is better with a set bitrate goal because you pretty much need to know the complexity of the source
[19:07] <Klaus_Dieter> well I would like to convert a dvd to mpeg4 using decent quality
[19:07] <Klaus_Dieter> that is my goal. Also I want every audio and subtitle to be in it
[19:08] <JEEB> you remove the b and pass settings, and switch to using a -preset that is generally fast enough for you (slowest that you still think is OK) and the highest crf value that still looks good to you
[19:08] <JEEB> -crf 23 is the default, -preset medium is the default
[19:09] <JEEB> you can try encoding a few thousand frames, into mkv for example and checking it out
[19:09] <Klaus_Dieter> I am currently doing this using this: http://paste.ubuntu.com/1195047/
[19:09] <JEEB> -ss seeks to somewhere, -t encodes a certain amount of time
[19:09] <JEEB> so you try with crf 23, if it looks good you try a higher one
[19:09] <Klaus_Dieter> so I remove -bt as well?
[19:10] <JEEB> if it looks bad you try a lower one
[19:10] <JEEB> yeah, remove that
[19:10] <JEEB> anyways, off to take a run
[19:10] <Klaus_Dieter> thanks for the hint and hf!
[19:10] <seblabel> for 5 minutes i have a 171mo file and so, for 132 minutes, i should have a 4514mo file
[19:11] <seblabel> that is good for my dvd size
[19:14] <burek> seblabel, your original video is 3 gb, right?
[19:15] <burek> did you try just remuxing it (without re-encoding, just change the container)
[19:15] <burek> something like ffmpeg -i myinput.avi -c copy -target pal-dvd myoutput.mpg
[19:16] <burek> or maybe it's better to do this: ffmpeg -i myinput.avi -map 0 -c copy -target pal-dvd myoutput.mpg
[19:16] <burek> since -c copy doesn't do what it actually might look it does
[19:19] <Mavrik> that won't work in an actual DVD player though
[19:20] <burek> well, if mpg container supports the a/v streams, why not
[19:20] <burek> if it doesn't it will throw an error anyway
[20:08] <seblabel> burek: i got this : Unrecognized option 'c'
[20:08] <seblabel> ffmpeg: failed to set value 'copy' for option 'c'
[20:10] <ubitux> too old version
[20:10] <ubitux> try -acodec copy -vcodec copy
[20:14] <seblabel> it's working
[20:14] <seblabel> but will it fits for a dvd video ?
[20:15] <seblabel> i mean, not in size, but in compatibility ?
[20:16] <seblabel> cause my final aiml is to burn the file on a dvd to watch the video on a tv-machine
[20:17] <seblabel> well, the re-muxing was ok, but the video is not readable
[20:18] <seblabel> thank you guys
[20:19] <seblabel> if i find a solution for this problem, i will come and share it
[20:19] <seblabel> the solution
[20:19] <seblabel> :D
[20:20] <Klaus_Dieter> what do I do for cropping? this crop filter should really not do anything if the input filesize is 720x576: crop=720:576:0:0 right?
[21:09] <relaxed> Klaus_Dieter: correct
[21:44] <smt> hi, i use the following command to convert various input formats to my target format ffmpeg -i "$f" -map 0 -filter:v scale="$res1":"$res2" -c:v libx264 -threads 0 -crf 18 -c:a libmp3lame -q:a 3 "${f%.$ext}.avi", it works well but it fails when trying to convert a matroska file with embedded subtitles, how can i convert all audio tracks, but drop the subtitles?
[21:45] <smt> and pleas dont mention that h264 in avi is a bad idea, i know about that
[21:50] <relaxed>  smt -map 0:v -map 0:a
[21:50] <relaxed> omit -map 0
[21:53] <smt> seems to work, thanks
[21:53] <smt> (once more)
[21:56] <seblabel> why putting x264 in a avi is bad ?
[21:57] <JEEB> anything with b-frames is
[21:57] <JEEB> because the format wasn't made to accomodate that
[21:57] <JEEB> people more or less are "OK" with MPEG-4 Part 2 because that had a more limited scope of b-frames
[21:57] <JEEB> and because people really ended up using it
[21:58] <seblabel> should .mp4 be used then ?
[21:58] <JEEB> mp4, flv, matroska... whatever is your fancy
[21:58] <seblabel> good to know
[21:59] <seblabel> first time here for me and i learnt a lot
[22:03] <Zeeflo> i need support :)
[22:04] <Zeeflo> my mkv's 720p and 1080p are lagging like ******
[22:04] <Zeeflo> debian serviio
[00:00] --- Mon Sep 10 2012


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