[Ffmpeg-devel-irc] ffmpeg.log.20141111

burek burek021 at gmail.com
Wed Nov 12 02:05:01 CET 2014


[00:29] <Sagi_> Hey guys, how can I convert MKV with SSA (or ASS) to MP4?
[00:36] <blippyp> Sagi_ ffmpeg -i input.mkv -c copy out.mp4
[00:40] <redxiizzle> if there any way to disable libdvdcss key caching at compile time?
[00:41] <redxiizzle> under mingw/windows, if fontconfig is enabled and saving to appdata mplayer crashes
[00:41] <redxiizzle> not sure why
[01:54] <scoofy> is there a simple way to extract aac audio without decoding?
[01:54] <scoofy> form a vid?
[01:54] <scoofy> and then I simply want to 'copy' that into antoher vid, without re-encoding (in other words, i want to copy audio from one vid to another)
[01:55] <c_14> ffmpeg -i video1 -i video2 -map 0:a -map 1:v -c copy outvideo
[01:57] <scoofy> if video2 exists as still frames, would this work?
[01:57] <scoofy> ffmpeg -i video1.mp4 -i video%04d.ppm -map 0:a -map 1:v out.avi
[01:57] <c_14> sure, you'll have to encode the video though
[01:57] <scoofy> well, better would be if i had the audio extracted separately
[01:58] <scoofy> then i could just 'add' that to encoding the second vid as audio stream
[01:58] <scoofy> mplayer -dumpaudio video.mp4 supposedly dumps 'raw' aac stream
[01:58] <c_14> You can do that.
[01:58] <scoofy> can I 'copy' that into the second vid as I encode it?
[01:58] <c_14> yes.
[01:58] <scoofy> using -i video.aac ?
[01:59] <c_14> Either with video.aac or with the actual video file.
[01:59] <scoofy> ok, thanks. i'll try.
[01:59] <c_14> Just map the audio stream from the one video and the other video stream.
[02:00] <scoofy> so, if i also wanna encode frames, something like:
[02:00] <scoofy> ffmpeg -i video1.mp4 -i video2%04d.ppm -map 0:a -map 1:a -vcodec libx264 out.avi
[02:00] <scoofy> ?
[02:01] <c_14> -map 0:a -map 1:v -c:a copy -c:v libx264
[02:01] <scoofy> ok, thanks for the tip.
[02:01] <scoofy> (i'm still a n00b in ffmpeg)
[03:28] <jswensen> I am using https://github.com/carsonmcdonald/HTTP-Live-Video-Stream-Segmenter-and-Distributor/tree/master to generate TS files for HTTP Live Streaming. I am using a command like ffmpeg -i %s -f mpegts -acodec libmp3lame -ar 32000 -ab 48k -s 480x480 -vcodec libx264 -b 110k -flags +loop+mv4 -cmp 256 -partitions +parti4x4+partp8x8+partb8x8 -subq 7 -trellis 1 -refs 5 -coder 0 -me_range 16 -keyint_min 25 -sc_threshold 40 -i_qfactor 0.71
[03:28] <jswensen> -b:v 110k -maxrate 110k -bufsize 110k -rc_eq 'blurCplx^(1-qComp)' -qcomp 0.6 -qmin 10 -qmax 51 -qdiff 4 -level 30 -aspect 1:1 -r 10 -g 30 -async 2 - | %s %s %s %s %s to generate TS segment at varying bitrates.
[03:28] <jswensen> The problem is that they all end up being larger than the specified bitrate by 35%-75% and the peak bitrate is 135%-160% over the target.
[04:00] <jswensen> Sprry, got disconnected. What is the best way to ensure the birate stays as close to the target rate as possible with as little over in peak as possible?
[04:16] <c_14> minrate maxrate 2pass ?
[04:27] <jswensen> i tried the minrate maxrate, but didnt try the 2 pass. i will go try that
[04:57] <scoofy> c_14, you here? i tried your command:
[04:57] <scoofy> <c_14> ffmpeg -i video1 -i video2 -map 0:a -map 1:v -c copy outvideo
[04:57] <scoofy> i get: Unrecognized option 'c'
[04:58] <scoofy> i won't use pastebin sites for 1 line
[04:58] <sacarasc> 1 line is the command.
[04:58] <sacarasc> Then there's version stuff.
[04:58] <scoofy> and 1 line is the output.
[04:58] <sacarasc> Then there's the error.
[04:58] <sacarasc> There's more than 1 line.
[04:58] <scoofy> the error is 1 line.
[04:59] <scoofy> Unrecognized option 'c'
[04:59] Action: sacarasc goes away, then.
[05:00] <scoofy> version number: ffmpeg version 0.8.16-6:0.8.16-1
[05:00] <scoofy> i think all the other data is irrelevant
[05:03] <sacarasc> 0.8 is ancient, upgrade.
[05:06] <sacarasc> In fact, 0.8.16 isn't even ffmpeg... It's Libav. #libav is their channel, but you can install/use ffmpeg on (I will presume Debian-like) https://trac.ffmpeg.org/wiki/CompilationGuide/Ubuntu or you can use one of these links:
[05:08] <scoofy> yea, this is cr**ppy libav stuff... so i'll need to download the 'real thing'
[05:08] <scoofy> for some reason, when i try 'apt-get ffmpeg' it says its at last version
[05:09] <scoofy> well it's ffmpeg package from libav
[05:10] <sacarasc> Previous Debian and Ubuntu releases packaged libav as ffmpeg, but it's not ffmpeg.
[05:15] <jswensen> I tried the minrate maxrate and 2pass, but when I was trying for 200kbps video and 48kbps video, the result was still about 320kbps total.
[05:18] <scoofy> sacarasc: unfortunately :/
[05:19] <scoofy> i'll dl update
[05:38] <petecouture> Does anyone know the best java library to use with ffmpeg?
[05:44] <petecouture> I can't find anything modern on the subject. 2009 is the last post about it.
[07:58] <p4plus2> What is a good strategy for improving framerate of x11grab capturing?  6 of my eight cores are inactive (even specifying -thread 8 doesn't help)
[07:58] <p4plus2> It doesn't matter whether I steam or record to RAM with a tmpfs or to my ssd, I cap out at 33 FPS
[07:58] <p4plus2> -threads 8*
[07:59] <p4plus2> I've tried a variety of presets -- no difference, ultrafast and medium result in the same framerate
[08:16] <FabTG> hi everyone, tried to convert basically : ffmpeg -i video.mp4 video.mpg , I had sound but no image, is this more complcated than that?
[08:17] <scoofy> maybe... -vcodec <codec> ?
[08:27] <FabTG> Video: h264, yuv420p, 1920x1080, 23.98 tbr, 23.98 tbn, 47.95 tbc
[08:28] <FabTG> scoofy: is that not standard for an mp4 file?
[08:28] <scoofy> it is
[08:28] <FabTG> ok...
[08:29] <FabTG> so I'm stuck
[08:29] <FabTG> ;)
[08:29] <scoofy> what is your goal?
[08:32] <FabTG> my computer is too "light" to read without lagging the initial mp4 video
[08:33] <FabTG> so I try to degrade it a little bit
[08:33] <blippyp> you probably need to re-encode changing the profile type so your system can handle it
[08:34] <scoofy> maybe you need to speicify some output codec? using -vcodec <codec>
[08:34] <blippyp> simply re-muxing into a different container isn't going to help you
[08:34] <scoofy> -vcodec mpeg4 or something
[08:38] <FabTG> maybe I need to read more things about video encoding, althoug I only wanted to quickly convert ;)
[08:39] <blippyp> p4plus2 - pastebin your command
[08:40] <FabTG> what?
[08:40] <blippyp> FabTG: you need to re-encode or use a faste device probably. I wouldn't switch from x264 personally - You would need to change your profile to baseline or main or something (its probably on high)
[08:42] <p4plus2> blippyp: http://p4plus2.pastebay.net/1520675
[08:42] <FabTG> blippyp: ok
[08:42] <p4plus2> this is one of many attempts but since all resulted in identical frame rate, that should do
[08:43] <p4plus2> also my configuration: ./configure --enable-gpl --enable-nonfree --enable-pthreads --enable-libx264
[08:44] <p4plus2> also output from a few seconds of recording: http://p4plus2.pastebay.net/1520678
[08:45] <blippyp> p4plus2: you're streaming it - good luck with that - I've personally had very little success myself with that...
[08:46] <p4plus2> blippyp: it doesn't make a difference whether I record or stream
[08:46] <blippyp> but my hardware sucks, which is what I think the problem(s) mostly come from for me
[08:47] <p4plus2> I don't think mine is hardware (or when steaming network related, I have a 128/15mbps connection)
[08:47] <blippyp> if you remove all that extra garbage and just do a -crf 24 -preset ultrafast, it should work fine I think - even on my crappy hardware I can do it.
[08:47] <p4plus2> my cpu is a 3.8GHz octocore
[08:47] <blippyp> but obviously you will want to re-encode it afterwards
[08:48] <blippyp> there can be many bottlenecks - you simply might just need a hardware accelerator - and I don't think that's supported, but I could easily be wrong
[08:49] <p4plus2> I guess I'll just have to keep trying
[08:49] <blippyp> p4plus2: this is one I use on my netbook:
[08:49] <blippyp> ffmpeg -s 1024x600 -f x11grab -i :0.0 -r 30 -c:v libx264 -crf 17 -preset ultrafast -an out.mp4
[08:50] <p4plus2> its odd because I can even record at medium or higher without a change in framerate
[08:50] <blippyp> I'm even using a crf 17 - but the ultrafast is what makes it happen I think
[08:51] <blippyp> I have also streamed it as well, but the results were less than ideal for me
[08:52] <p4plus2> blippyp: dropping the -r just causes massive frame drops -- like 55 of 60 per second
[08:53] <blippyp> -threads don't work with x264 - it's uses autodetects how many or only uses one or something I believe
[08:53] <p4plus2> I already dropped -threads too
[08:53] <blippyp> I've seen my audio configuration DESTROY my capture - maybe you need to play with that
[08:53] <blippyp> the threads won't make a difference, just remove that option
[08:54] <p4plus2> I have removed it, also I'm not even capturing audio
[08:54] <blippyp> you're also doing a large video - you should try dropping it to at least 720p first and try to get that working I think
[08:55] <p4plus2> changed to 720p -- no difference
[08:55] <p4plus2> huh: Stream #0:0: Video: rawvideo (BGRA / 0x41524742), bgra, 1920x1080, 29.97 fps, 29.97 tbr, 1000k tbn, 29.97 tbc
[08:55] <p4plus2> I wonder why....?
[08:56] <scoofy> you need -framerate 30000/1001
[08:56] <blippyp> that -g might be hurting you - not sure, never used it, but from what I just read in the manual, I'd bet it's really high
[08:56] <scoofy> and -r 30000/1001
[08:57] <p4plus2> scoofy: I am trying to record ideally at 60fps -- the problem is I am only getting 30
[08:57] <p4plus2> but my system isn't really being taxed so I feel like I am missing an option
[08:58] <scoofy> you're trying to record screen grab?
[08:58] <p4plus2> x11grab, yeah
[08:58] <blippyp> and stream it
[08:58] <p4plus2> the stream part can come later
[08:59] <p4plus2> since it doesn't matter whether I save it to RAM/SSD or stream -- all three have the same frame rate limit of 38
[08:59] <blippyp> that's weird
[08:59] <scoofy> why do you need such high frame rate?
[09:00] <p4plus2> I was doing a bit of game streaming and unfortunately they look rather choppy at 30fps
[09:00] <p4plus2> had enough complaints to try and do something about it
[09:01] <p4plus2> and frankly even I notice it to an extent
[09:01] <blippyp> by going 60 you are literally requiring twice the resources man
[09:01] <blippyp> not worth it in my opinion for the 2/10 guys who can 'apparently' notice the difference
[09:01] <p4plus2> blippyp: considering 720p and 1080p are both limited to 38FPS....
[09:02] <p4plus2> that tells me the problem is elsewhere
[09:02] <blippyp> I agree, something 'fishy' is happening for you I think
[09:02] <blippyp> wait and ask c_14 - that guy really knows his shit
[09:02] <p4plus2> using the native ffmpeg on my system is even worse at 17FPS
[09:03] <blippyp> he's usually on during the day (for me) and it's 3 in the morning right now here
[09:03] <p4plus2> recompiling it from scratch hit 38 right away
[09:04] <blippyp> I don't know what to tell you - even with my crappy systems I've played with 60fps a couple of times for shits and giggles and as far as I know it worked fine - the files stated so - i couldn't see a difference
[09:04] <blippyp> apparently the source files I used were 60fps to begin with so unless that was bullshit....???
[09:04] <blippyp> as far as I'm concerned anything over 30 is only useful if you want to slow-motion your video
[09:05] <scoofy> human eye can hardly perceive much more than that
[09:05] <blippyp> 'apparently'
[09:05] <blippyp> all the 'cool' kids are claiming otherwise these days
[09:05] <blippyp> I call bullshit myself, but whatever - don't really care...  ;)
[09:05] <scoofy> i wouldn't give 2 shits for streaming video
[09:06] <scoofy> being "only" 30 fps...
[09:06] <blippyp> hell - I'd drop it down to 24 just cause it's easier on resources.... haha
[09:06] <p4plus2> scoofy: I'll be honest I feel its more to do with the vsync isn't picking "every other frame" so to speak
[09:06] <blippyp> could be - not sure - I never use that option either
[09:06] <scoofy> iirc NTSC is at ~60 FPS, that get halved via interlacing so you get ~30 FPS
[09:07] <scoofy> (but this is not NTSC)
[09:07] <scoofy> just that also works at 60 fps i think
[09:08] <blippyp> yeah - never considered that - maybe the source I used to 'play with 60 fps' was interlaced....  no idea...
[09:09] <blippyp> maybe that's why I never noticed - could be limited by my crappy monitors as well... haha
[09:09] <blippyp> I know my tv goes to 60 though, and I've never noticed a difference between watching videos on the computer compared to the tv....
[09:10] <blippyp> I've always just assumed I was part of the lucky 99% who can't tell either way...  ;)
[09:10] <p4plus2> I generally don't notice a difference between 30 and 60 for the most part
[09:11] <blippyp> FabTG: you still around?
[09:11] <p4plus2> but it does make a difference in the recordings I've done, which makes me think the "30 of 60" frames its not picking frames evenly so to speak
[09:11] <p4plus2> does that make sense?
[09:12] <klaxa> have you used -framerate instead of -r?
[09:12] <blippyp> I'd say your system can't handle recording that much myself
[09:12] <scoofy> -framerate is for input
[09:12] <scoofy> -r is for output
[09:12] <klaxa> iirc -framerate is supposed to be used with x11grab, it will duplicate frames though if your throughput is too low
[09:12] <scoofy> isn't it?
[09:12] <p4plus2> klaxa: I haven't, I'll try it
[09:12] <scoofy> p4plus2, -framerate specifies input rate... so if your *input* rate is 60, change -r to that
[09:13] <blippyp> he might need to specify both input and output frames though...
[09:13] <scoofy> yep
[09:13] <scoofy> -framerate 60 -r 60
[09:13] <p4plus2> oh wow
[09:13] <scoofy> assuming he wants 60 fps output
[09:13] <p4plus2> would you look at that
[09:13] <scoofy> or -framerate 60 -r 30
[09:13] <blippyp> working now?
[09:13] <scoofy> ^ for 30 fps output (but that wouldn't make sense for 60 fps screen grab)
[09:13] <p4plus2> that indeed did the trick
[09:13] <p4plus2> significantly better now
[09:13] <klaxa> better check the encoded video, like i said, it might duplicate frames
[09:14] <scoofy> i had a similar issue with an NTSC video (audio out of sync)
[09:14] <blippyp> good call klaxa
[09:14] <scoofy> specifying both -r and -framerate fixed it
[09:14] <p4plus2> klaxa: I will but this time the "stream 0" says 60FPS when before it was always 30
[09:14] <scoofy> so it was incorrect
[09:14] <scoofy> until you specified -framerate 60
[09:14] <klaxa> could be 60 times the same frame per second
[09:15] <p4plus2> scoofy: correct
[09:15] <blippyp> not sure how to tell the difference though
[09:15] <blippyp> pull two consecutive frames out and md5 them???
[09:15] <scoofy> i think i sometimes get a "duplicate frames" warning automatically
[09:15] <scoofy> or was it in mencoder? not sure
[09:16] <blippyp> isn't there a flag in the codecs to join duplicates?
[09:16] <klaxa> not sure x11grab reports duplicate frames in that case, mostly i only get dropped frames
[09:16] <p4plus2> I have dup=0
[09:16] <blippyp> if he ran one of thoseont he file afterwards and it dropped back down to 30 that would be a good sign
[09:16] <p4plus2> so I think I am safe
[09:16] <klaxa> wouldn't that result in variable frame rates? i wouldn't trust a streaming service with that
[09:18] <klaxa> also, checking for duplicate frames might actually be easier by hand, by stepping through images, checking md5 hashes will probably not work since the codec might change the frame even if the input didn't change unless the codec was lossless
[09:18] <p4plus2> visually it looks much better, plus I show dup=0
[09:19] <p4plus2> drop=10 after five minutes or so now which is reasonable enough
[09:19] <blippyp> yeah - that's why I brought up the option with the codecs stripping duplicates - I also doubt the md5 method would work either
[09:20] <blippyp> how are your resources - are they maxing out?
[09:20] <p4plus2> they look fine
[09:20] <blippyp> if they're not - then you're still running into some kind of conflict somewhere probably
[09:20] <blippyp> it shouldn't drop frames
[09:20] <p4plus2> its not
[09:20] <p4plus2> (00:20:52) p4plus2: visually it looks much better, plus I show dup=0
[09:20] <blippyp> you just said it dropped 10 frames...???
[09:21] <p4plus2> 10 over five minutes
[09:21] <p4plus2> that could be easily attributed to a random lag spike
[09:21] <blippyp> dup=0 is probably a good sign
[09:21] <klaxa> where are you writing to? SSD? maybe writing to ram would be faster
[09:21] <klaxa> maybe check your io while recording
[09:21] <blippyp> ya, I suppose the lag could account for it...
[09:21] <blippyp> you're streaming it also right?
[09:21] <p4plus2> klaxa: I'm writing to a stream, but tmpfs works just as well now
[09:22] <klaxa> ah
[09:22] <p4plus2> 128 down and 15 up so I think thats pretty solid for streaming
[09:22] <blippyp> well, either way much better - cool
[09:22] <blippyp> tell everyone you couldn't figure out how to switch to 60 and watch them all still complain about it...
[09:22] <blippyp> hahaha
[09:22] <p4plus2> yeah this problem has been bugging me for quite a while, I don't know how I never came across -framerate
[09:23] <p4plus2> blippyp: I'll probably try that and see what happens
[09:23] <blippyp> I would - just to see if they actually noticed
[09:23] <blippyp> plus I enjoy screwin' with people...  ;-P
[09:23] <p4plus2> I may say nothing to see if anybody says something first
[09:23] <blippyp> seriously you should - just as a social experiment
[09:24] <blippyp> but there will likely be someone looking at the numbers who will speak up first
[09:27] <p4plus2> anyways thanks for the help everybody, much appreciated
[09:27] <scoofy> yw
[09:28] <blippyp> FabTG: I'm taking off - gonna go do some programming, but if you read this - You don't have to encode your entire video to see if that profile changing will work for you (although I'm betting it will) - You can just record a short clip (like a couple minutes) to test and see how your system handles the difference.
[09:30] <klaxa> ><FabTG> my computer is too "light" to read without lagging the initial mp4 video
[09:31] <klaxa> i would suggest using a player that supports caching and if available hardware decoding
[09:32] <blippyp> that's what I do - my systems are crap for playback these days also (everything on a high profile now) - and I couldn't be bothered to re-encode every movie I download - but my blu-rays all play them fine luckily... :)
[10:18] <bencc1> can I use ffmpeg to create a virtual camera from my desktop?
[10:30] <hans_s> hi, I have some questions about https://github.com/FFmpeg/FFmpeg/blob/master/LICENSE.md#incompatible-libraries
[10:31] <hans_s> I built ffmpeg binaries, which are statically linked against the ffmpeg libraries and some 3rd party libraries, including libx264 (GPL) and libfdk-aac (nonfree)
[10:32] <hans_s> would those ffmpeg binaries really be unredistributable? could I get in trouble for redistributing them? or am I overreacting?
[10:46] <relaxed> hans_s: yes, because libfdk-aac is non-free
[10:47] <relaxed> (yes to the first two questions)
[10:48] <hans_s> yes, it's marked nonfree, but I didn't find any explanations, why. also I'm a noob when it comes to licenses, that's why I'm asking
[10:49] <relaxed> google the license for each and then google why they're not compatible
[10:50] <hans_s> for example, I have no idea what license I'm breaking (ffmpeg/libx264/libfdk-aac)
[10:51] <hans_s> ok, thought maybe someone already knew the answer, before I start researching
[10:52] <relaxed> the license info should be in the source dir for each.
[10:56] <relaxed> in short the libfdk-aac's license isn't compatible with the gpl
[10:56] <hans_s> so, I'm violating GPL, if I redistribute that binaries?
[11:07] <relaxed> yes
[11:12] <hans_s> ok, thanks a lot, relaxed
[11:29] <ribasushi> hi
[11:30] <ribasushi> I am trying to wrap my head around ffmpeg in general, so as a start I am trying to get the following to work:
[11:30] <ribasushi> ~$ ffmpeg -f v4l2 -i /dev/video1 - | mplayer -
[11:30] <ribasushi> of course this doesn't function because it needs to know how to format the stuff off the camera
[11:31] <ribasushi> the source is this: http://paste.scsys.co.uk/438728
[11:31] <ribasushi> I want to get the h264 output and *without processing* send it to mplayer
[11:31] <ribasushi> is this possible?
[11:58] <anddam> I have a stereo mp3 file that contains voice recording, it's stereo and I want to have it converted to mono, is https://trac.ffmpeg.org/wiki/AudioChannelManipulation#a2monostereo the right approach?
[11:58] <anddam> I'm at the same time transcoding it to AAC using   -c:a libfdk_aac -b:a 48k
[11:58] <anddam> should I do it in two steps?
[11:59] <anddam> sorry I meant https://trac.ffmpeg.org/wiki/AudioChannelManipulation#stereomonostream
[11:59] <anddam> that is just -ac 1
[12:09] <anddam> I have this output for option at start of transcoding "Stream #0:0: Audio: mp3 (libmp3lame), 11025 Hz, mono, s16p" for the mp3 and "Stream #0:0: Audio: aac (libfdk_aac) (mp4a / 0x6134706D), 11025 Hz, mono, s16, 48 kb/s" for the AAC
[12:09] <anddam> yet the mp3 is roughly half the size of the m4a
[12:09] <relaxed> ribasushi: read https://trac.ffmpeg.org/wiki/Capture/Webcam first, but something like, ffmpeg -f v4l2 -i /dev/video1 -c:v libx264 -f flv - | mplayer -
[12:10] <anddam> oh I figured, I was using -q:a 8 for the mp3 encoder and that resulted in an average bitrate of 24kb/s
[12:11] <ribasushi> relaxed: I actually got things to record fine with:
[12:11] <relaxed> yes, the range is 0 - 9, 0 being highest quality
[12:11] <anddam> now using an explicit -b:a 48k
[12:11] <ribasushi> relaxed: ffmpeg -report -s 1920x1080 -f v4l2 -vcodec h264 -i /dev/video1 -copyinkf -vcodec copy test.mp4
[12:12] <ribasushi> works in the sense it does not consume any CPU
[12:12] <ribasushi> and writes at about 3mbit/s
[12:12] <anddam> relaxed: is 11025 Hz/mono/48 kb reasonable for a talked podcast?
[12:12] Action: ribasushi will wait for anddam to get help ;)
[12:14] <relaxed> anddam: should be, what do your ears tell you?
[12:14] <anddam> my ears say that mp3 24kbps is a bit shitty
[12:14] <anddam> AAC 48kb sounds very good
[12:14] <anddam> I mean both mono 11Khz
[12:15] <relaxed> ribasushi: it's because you're stream copying, which is optimal
[12:15] <ribasushi> relaxed: I got more questions though, just didn't want to cross-talk ;)
[12:16] <anddam> is MPEG the appropriate container for an AAC encoded audio stream?
[12:16] <anddam> I guess that's actually "MPEG-4"
[12:16] <relaxed> anddam: sure
[12:16] <relaxed> ribasushi: shoot
[12:17] <ribasushi> relaxed: so the above still doesn't flow into mplayer correctly (I get nothing on the screen), but even if I just save to a file and play it after - the video is twice as fast
[12:17] <ribasushi> what do I need to adjust for that?
[12:19] <relaxed> ffmpeg -report -s 1920x1080 -f v4l2 -vcodec h264 -i /dev/video1 -copyinkf -vcodec copy -f flv - | mplayer -
[12:19] <relaxed> the mp4 container has to be written completely before you can play it
[12:19] <ribasushi> right, I get capture (camera is on, stats are rolling) and no videoscreen
[12:20] <ribasushi> err I am aware of that
[12:20] <ribasushi> I mean once I write out the container
[12:20] <ribasushi> (ffmpeg stops)
[12:20] <ribasushi> the resulting mp4 is twice the speed
[12:20] <relaxed> oh, does ffplay play it?
[12:20] <ribasushi> let me check...
[12:20] <relaxed> you may have to set the input frame rate
[12:21] <ribasushi> ok wtf... things work now
[12:21] Action: ribasushi chalks up to a fluke moves on
[12:21] <ribasushi> so next question:
[12:24] <ribasushi> relaxed: https://etherpad.mozilla.org/BFPkw4sg6n
[12:24] <ribasushi> (I'll be updating it as I go)
[12:24] <ribasushi> why the error / what am I doing wrong
[12:25] <relaxed> https://trac.ffmpeg.org/wiki/Capture/ALSA
[12:30] <ribasushi> relaxed: this got me on the right track, thank you very much
[12:30] <ribasushi> still fiddling with settings a bit...
[12:36] <relaxed> you're welcome
[12:44] <anddam> weird, "-strict 2 -vn -sn -c:a libfdk_aac -b:a 32k -ac 1 -ar 11025 scaled.m4a" results in "ID_AUDIO_BITRATE=32000"
[12:44] <anddam> while "-strict 2 -vn -sn -c:a libfdk_aac -b:a 32k -ac 1 -ar 11025 scaled.aac" results in "ID_AUDIO_BITRATE=29888"
[12:50] <Guest80396> hello all, I am writing a script that runs ffmpeg to convert a video from mpeg2 to mpeg4 and have added a function to remove the file after successful completion, but when I quit the transcoding no error is returned and my file gets deleted. Is there a way to tell if ffmpeg has been told to quit rather than just finished successfully. Thanks in advance for any help.
[12:52] <Guest80396> btw I am checking the exit code (with $?) to do this
[12:56] <klaxa|work> you could compare duration of the files maybe?
[12:57] <Guest80396> Ahh that's a good catch I will try that Thank you
[12:58] <klaxa|work> checking whether or not ffmpeg was stopped because the file ended, it received a "q" or received a SIGINT seems rather hard
[12:58] <Guest80396> Yes, I am finding that out :)
[12:58] <klaxa|work> wow what's with my english... i'm really tired
[13:02] <ribasushi> relaxed: the alas-capture page showed me how to get a stable name for the audio
[13:02] <ribasushi> relaxed: how do I get the same for v4l2 (I don't want to use -i /dev/video1)
[13:02] <ribasushi> (I did look on the wiki - either I am blind, or stupid, or it isn't there ;)
[14:15] <anddam> bye, thanks
[14:34] <ribasushi> relaxed: just wanted to let you know that I got what I wanted so far
[14:35] <ribasushi> ffmpeg is awesome
[14:35] <ribasushi> ffmpeg -y -report -f v4l2 -vcodec h264 -video_size 1024x576 -i /dev/video1 -f alsa -itsoffset 0.3 -ar 44100 -ac 1 -i "default:CARD=Intel" -c copy -f matroska - | netcat 192.168.0.11 30000
[14:46] <DelphiWorld> yo
[15:09] <DelphiWorld> yo c_14
[15:10] <DelphiWorld> i have a ts stream where there's 4 substreams
[15:10] <DelphiWorld> 1 video 2 audio and one subtitle
[15:10] <DelphiWorld> how to pickup one audio using  -map?
[15:15] <DelphiWorld> dont wory i got it
[15:15] <DelphiWorld> mkv is so dick:P
[15:15] <DelphiWorld> can accept any codec!
[18:09] <Guest74> hi o/
[18:22] <Will> i have a small problem
[18:22] <Will> anyone can help me ? :D
[18:22] <Will> [Parsed_subtitles_1 @ 0x686b80] fontconfig: cannot find font 'Arial', falling ba
[18:23] <Will> https://zerobin.net/?66ceb91390d077b5#9IMXbv+cH2hjmNlcbCvj5x+ff94xCzuJZroifMFI/OA
[18:30] <sacarasc> Will: And?
[18:30] <Will> and ...
[18:30] <Will> it's not a error ?
[18:30] <sacarasc> No.
[18:30] <sacarasc> It's a warning.
[18:31] <sacarasc> It's going to use a different font.
[18:31] <Will> before i don't have this error
[18:32] <Will> (i reinstate ffmpeg today)
[18:34] <Will> this warming *
[18:57] <oerg866> Hello people
[18:58] <oerg866> I was wondering, if I capture a dshow source from FFMPEG in 720x576 25fps, but the source connected to that capture device is acutally 288p 50fps progressive scan, how do I make the output be the same 288p 50fps format again? (Like DSCaler's "Old Game" filter)
[19:00] <oerg866> (for additional information: I'm capturing some SNES stuff)
[19:02] <oerg866> I believe the correct description of what I'm trying to do would be "Each field gets its own 720x288 frame"
[19:02] <iive> -vf yadif=send_field
[19:04] <iive> that's yet another de-interlace filter, and this option make it output one frame for each field.
[19:07] <oerg866> that was quick
[19:07] <oerg866> thank you :)
[19:23] <kxra> when i use -acodec opus it works fine normally, but when i am trying to use it while concat-ing two files i get this: Unable to find a suitable output format for 'opus'
[19:23] <kxra> opus: Invalid argument
[19:42] <kxra> trying libopus instead of opus doesn't help
[19:44] <kxra> oh my bad, it was due to bad syntax
[19:55] <ribasushi> is there any way to have ffmpeg start all inputs etc, but to actually begin the output recording on a signal or somesuch?
[19:55] <ribasushi> I am writing a script that starts recording from multiple sources (one of them is not ffmpeg based), looking for ways to sync them at record time
[20:20] <AdamJohn> Hello people... If I try to reencode a video, in middle of which there are zeroes instead of frames, the output has replicated frame... How can I just omit the missing frames thus jumping to the next good frame? Thanks
[21:45] <ribasushi> ok this is aggravating
[21:46] <ribasushi> I have one file with a perfectly synced audio/video track, and I am trying to PIP it with another video-only file
[21:46] <ribasushi> like so:
[21:46] <ribasushi> http://paste.scsys.co.uk/438821
[21:46] <ribasushi> the problem is that the resulting audio is out of sync even with the image it was synced with
[21:46] <ribasushi> (by a large ~1 sec margin)
[21:46] <ribasushi> what am I doing wrong?
[22:34] <harovali1> hi,  if I want to create a video composed of photos , I can use a command like this: ffmpeg -framerate 0.33 -pattern_type glob -i '*.jpg' -c:v copy out.mp4
[22:35] <harovali1> the problem is that the framerate should be higher, in order for the video to 'refresh' faster that the photos change from one to another.
[22:35] <harovali1> how can I achive that ? And what's the name of such operation ?
[22:35] <c_14> What?
[22:36] <c_14> Can you explain?
[22:37] <harovali1> f.i. if I play mplayer out.mp4 , the video is somewhat problematic, becasue f.i., pressing arrow left or arrow right , does not render correct images
[22:38] <harovali1> maybe it is lacking an index, but maybe also the framerate should not be the same frequency at which I want the photos to alternate in the video
[22:38] <c_14> On mplayer arrow left and arrow right will jump n seconds to the nearest keyframe.
[22:38] <Will> stop hl please
[22:38] <Will> xD
[22:39] <c_14> harovali1: https://trac.ffmpeg.org/wiki/Create%20a%20video%20slideshow%20from%20images
[22:39] <c_14> You can increase the fps of the output if you think that'll help.
[22:47] <harovali1> c_14 tanks
[22:49] <harovali1> sometimes I get '100 buffers queued in output stream 0:0, something may be wrong.' , however the video gets generated. What does this signal?
[22:49] <c_14> I'm not entirely sure, but you can probably ignore it.
[22:52] <ribasushi> anyone has ideas about my question with the desyncing audio?
[22:53] <c_14> No clue, sorry. Might want to wait around or ask the ml.
[22:58] <ribasushi> aight
[23:08] <danomite-> I've got an error about non-monotonous DTS http://dpaste.com/0MPXDF6 , any suggestions on how to fix it?
[23:10] <sacarasc> That's a warning, not an error.
[23:12] <danomite-> ok, I still need to fix it, the video stalls when the error appears
[00:00] --- Wed Nov 12 2014


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