[Ffmpeg-devel-irc] ffmpeg.log.20140212

burek burek021 at gmail.com
Thu Feb 13 02:05:02 CET 2014


[00:45] <superware> what's the difference between PTS and DTS?
[01:03] <superware> I need to sync video frames for display, how should I go from PTS to time?
[01:10] <Logicgate> hey guys everytime I run ffprobe it head a huge header with useless information
[01:10] <Logicgate> http://pastebin.com/Tu8r8tnb
[01:10] <Logicgate> I'm assuming I have an old version of ffprobe
[01:11] <Logicgate> Since I can't format the data in JSON, or can't run the -v quiet setting
[01:12] <Logicgate> is there a workaround?
[01:13] <llogan> Logicgate: get a non-ancient ffprobe
[01:14] <Logicgate> yeah
[01:14] <llogan> both supply ffprobe, IIRC
[01:17] <Logicgate> thanks llogan
[01:18] <Logicgate> both links don't work
[01:19] <Logicgate> ffmpeg.gusari.org is down
[01:19] <Logicgate> and johnvansickle's builds time out when downloading
[01:20] <klaxa> ffmpeg.gusari.org isn't down
[01:21] <klaxa> at least not from here
[01:21] <Logicgate> it's good now
[01:21] <Logicgate> I had to reload a few times
[01:21] <Logicgate> now just unpack that and ./ffmpeg?
[01:21] <Logicgate> and it'll install it?
[01:21] <klaxa> no need to install
[01:22] <klaxa> unpack it and then run it
[01:22] <Logicgate> that's so simple.
[01:22] <Logicgate> that's too simple
[01:22] <Logicgate> lol
[02:12] <Logicgate> Invalid data found when processing input
[02:12] <Logicgate> What could cause this
[02:12] <Logicgate> I'm running the latest static build trying to apply a watermark to an mp4
[02:12] <Logicgate> ./ffmpeg -i media/test.mp4 -vf 'movie=media/1_1392167471_52faca2f392af.png [watermark]; [in][watermark] overlay=0:0 [out]' w_test.mp4
[02:12] <Logicgate> that's the command.
[02:16] <Logicgate> Do the static builds have all the codecs?
[02:19] <Logicgate> llogan, I figured it out :P
[02:19] <Logicgate> thanks
[02:19] <llogan> and you don't need to use the movie multimedia source filter: ffmpeg -i input.mp4 -i logo.png -filter_complex "[0:v][1:v]overlay[out]" -map "[out]" -map 0:a -codec:a copy output.mp4
[02:53] <Hello71> which is preferable: -acodec, -codec:a, -c:a
[03:23] <superware> I'm using libav to play a live network stream, does it make sense to render frames as they arrive, without any sync?
[03:26] <relaxed> Hello71: latter
[03:27] <relaxed> but they're all synonymous
[03:35] <superware> anyone?
[04:35] <wolfman2000> Evening. On Mac OS X Mountain Lion or higher, is there a standard way to compile and distribute a binary for a repository? Or is there a different method preferred these days?
[04:36] <wolfman2000> err, distribute a compiled library. A *.a file
[07:33] <Keestu> hi , how to get the  pitches of a texture?
[09:05] <__raven> hi
[09:05] <__raven> ustream rtmp streaming: input output error on ingest server - how to find out why?
[09:41] <Keestu> hi,  av_read_frame (), i understand it reads the packet, but what i do not understand is does the syncronization between server and this api is taken care by framework or do we have to take care ?. Sorry if the question is very basic. i am at beginning level of exploring ffmpeg.
[10:08] <__raven> ustream rtmp streaming: input output error on ingest server - how to find out why?
[10:14] <__raven> anything going wrong with headers/container: different on windows and linux versions windows streams to ustream but it does not appear and on other server the stream is played back only when i stop the stream so its only buffered - whats that?
[13:16] <__raven> ustream rtmp streaming: input output error on ingest server - how to find out why?
[13:16] <__raven> anything going wrong with headers/container: different on windows and linux versions windows streams to ustream but it does not appear and on other server the stream is played back only when i stop the stream so its only buffered - whats that?
[14:30] <davez> Hi all
[14:31] <davez> I am using ffmpeg to add srt subs to a mp4 file using
[14:31] <davez> "./ffmpeg -i in.mp4 -f srt -i in.srt -c:v copy -c:a copy -c:s mov_text out.m4v"
[14:31] <davez> it works a bit
[14:31] <davez> some lines do not show up in the file:
[14:32] <davez> probably because i receive the following message:
[14:32] <davez> invalid UTF-8 in decoded subtitles test; maybe missing -sub_charenc
[14:32] <Fusl> can someone tell me if there's a way to exit after 3 hours runtime?
[14:32] <davez> i have checked the srt file and the missing lines seem normal to me
[14:32] <Fusl> i'm dumping a mmsh stream which often freezes and then the ffmpeg process gets stuck
[14:33] <Fusl> i can't even ctrl^c the ffmpeg process anymore if it's freezed
[14:33] <davez> ps grep kill ?
[14:33] <Fusl> davez: i want to do it automatically
[14:33] <Fusl> i tried with timeout 3h in front of it but then the ffmpeg doesn't even begin to read the mmsh stream
[14:35] <davez> lol fusl
[14:36] <davez> this looks okay to me
[14:36] <davez> http://www.ict.griffith.edu.au/anthony/software/timeout.sh
[14:40] <Fusl> someone said i should uses -shortest to prevent such freezes but it didn't work :(
[14:43] <davez> i probably would solve it through making a file when it starts and a 2nd script that sleeps 180 x 60 seconds then checks if the still exists
[14:43] <davez> is so killall ffmpeg ;)
[16:32] <svyatko> hi guys, anyone here good with ffmpeg pipes? i need some help piping output of one ffmpeg to another one
[16:32] <Hello71> !ask
[16:32] <Hello71> ballocks
[16:35] <svyatko> i have the following:
[16:35] <svyatko> WORKS fine: ./ffmpeg -i 'udp://239.0.0.5:5000' -c:v copy -c:a copy -f nut pipe:| ./ffmpeg -f nut -i pipe: -c:v copy -c:a copy -f flv
[16:36] <svyatko> DOESNT WORK: ./ffmpeg -i 'udp://239.0.0.5:5000' -c:v copy -c:a copy -f nut pipe:| ./ffmpeg -f nut -i pipe: -c:v copy -c:a copy -f flv | ./ffmpeg -f nut -i pipe: -c:v copy -c:a copy -f flv
[16:37] <svyatko> getting the following error for the second pipe output: [nut @ 0x2b91420] No main startcode found. pipe:: Invalid data found when processing input
[18:28] <bmhm> Hi there. I'd like to run ffmpeg & ffserver on a raspberry pi. Any chance of doing this? Does ffmpeg encoding support hardware encoding yet?
[18:30] <clever> not that i know of
[18:30] <clever> but i have made a mostly working hardware decode
[18:30] <clever> b frames mess it up right now, and it chews thru a ton of memory bandwidth
[18:32] <bmhm> clever: i only need encoding, though
[18:32] <clever> where will the video come from?
[18:35] <__raven> ustream rtmp streaming: input output error on ingest server - how to find out why?
[18:35] <__raven> anything going wrong with headers/container: different on windows and linux versions windows streams to ustream but it does not appear and on other server the stream is played back only when i stop the stream so its only buffered - whats that?
[18:36] <bmhm> clever: usbtv driver /dev/video0
[18:36] <clever> bmhm: and that outputs raw video frames or pre-encoded video?
[18:36] <bmhm> raw. sadly.
[18:36] <clever> ah
[18:36] <clever> so that will eat a ton of usb bandwidth as well
[18:36] <bmhm> Stream #0:0 -> #0:1 (rawvideo -> libx264)
[18:37] <clever> id recomend you start by looking at the video encoding example in /opt/vc/src/
[18:37] <bmhm> well, usb bandtwidth - the heck with it.
[18:37] <bmhm> I think a raspberry pi is not a good choice.
[18:37] <clever> ive had plans to make a rpi based upnp transcoder
[18:37] <bmhm> any ideas for a small form factor encoding station, headless linux?
[18:37] <clever> decode the video, resize it, re-encode it, stream it over upnp to less capable devices
[18:38] <clever> http://www.raspberrypi.org/phpBB3/viewtopic.php?f=70&t=61565
[18:39] <clever> bmhm: if you subscribe to this thread, youll get more info if i finish my ffmpeg patches and start on the encode side
[18:39] <bmhm> ok thanks.
[18:39] <clever> its currently able to hardware decode video and play it back via dispmanx
[18:40] <clever> but b frames mess up the order of the output
[18:40] <bmhm> clever: any idea for small form factor encoding hardware, running linux?
[18:40] <bmhm> I could use my tv station pc, though
[18:41] <clever> either get the encoding example from the hello_pi stuff to work, or do software encoding on a system with decent cpu power
[18:41] <clever> or get a proper tv capture device like a pvr-150
[18:41] <clever> or one of the usb based encoders
[18:42] <bmhm> can you msg me some please?
[18:42] <clever> http://www.hauppauge.com/site/support/support_pvr150.html
[18:42] <clever> this is a pci based capture card, coax/svideo/composite in, mpeg2 out
[18:43] <bmhm> pci wont help on araspberry pi
[18:43] <clever> yeah, you would have to go with a normal x86 desktop
[18:43] <clever> but the cpu power wont matter
[18:43] <clever> ive done it on a P2 400mhz
[18:43] <bmhm> I want webm anyway
[18:44] <clever> is the source analog or digital tv?
[18:44] <bmhm> analog, composite.
[18:44] <clever> http://www.mythtv.org/wiki/Video_capture_card#Analog_Hardware_Encoder_Cards
[18:44] <bmhm> I currently use this device: http://linuxtv.org/wiki/index.php/Easycap#USBTV007_EasyCAP
[18:44] <clever> Most hardware-encoding cards output an MPEG-2 stream, which can simplify backing up to DVD.
[18:45] <bmhm> WinTV-PVR-USB2 sounds promising
[18:45] <clever> acording to the mythtv wiki, most hardware encoders produce mpeg2
[18:49] <bmhm> aww they are too expensive
[18:49] <bmhm> its cheaper to find a small x86 pc
[18:51] <clever> but that may not have enough cpu power to encode
[18:54] <bmhm> if i want to convert to webm/vp8 anyway?
[19:02] <bmhm> clever: i think I'll stream h264 to the web then, using a hauppauge hd-dvr 1/2.
[19:02] <bmhm> I might be able to grab one from ebay for a low budget
[19:04] <ChocolateArmpits> There is a number of deinterlace filters available. Do any others produce better image quality when compared to yadif ?
[19:09] <bmhm> clever: thanks, hauppauge will probably do for now. No webm/vp8, but heck, mp4/h264 will also do.
[19:16] <wodim> hello
[19:16] <wodim> how can I split a VOB file using the dvd_nav_packet stream it already has?
[19:26] <llogan> ChocolateArmpits: have you tried w3fdif? (I haven't).
[19:27] <llogan> also see mcdeint
[19:38] <YuGiOhJCJ> Hello, I got some "ALSA buffer xrun" messages when I am capturing audio and video over the network (i.e., an output file stored on a NFS share or an output stream like twitch.tv) but when the output is a local file (on my hard disk drive) I got no "ALSA buffer xrun" messages... Do you know how to avoid this message with ffmpeg over the network ?
[19:39] <YuGiOhJCJ> My command is: $ ffmpeg -y -f alsa -i default -f x11grab -r 10 -s 640x480 -async 1 -i :0.0 -strict -2 -c:a aac -c:v libx264 -pix_fmt yuv420p -preset ultrafast -s 640x480 -threads 0 -ar 44100 -b:a 64k -b:v 64k -bufsize 64k -f flv out.flv
[19:41] <llogan> YuGiOhJCJ: does it create a bad output when the xruns occur?
[19:41] <YuGiOhJCJ> yes, the audio is out of sync
[19:42] <YuGiOhJCJ> I am wondering if it is an ALSA problem or a FFmpeg problem... Maybe both
[19:42] <llogan> do you get xruns if you only encode the audio?
[19:42] <YuGiOhJCJ> Not tested
[19:43] <YuGiOhJCJ> I will tell you that in few seconds
[19:46] <YuGiOhJCJ> No if I encode only audio, I got no more xruns
[19:47] <ChocolateArmpits> llogan, well I haven't really done any testing with available ones yet, but maybe others have, so that's what I'm asking
[19:47] <YuGiOhJCJ> My new command is: $ ffmpeg -y -f alsa -i default -strict -2 -c:a aac -c:v libx264 -pix_fmt yuv420p -preset ultrafast -s 640x480 -threads 0 -ar 44100 -b:a 64k -b:v 64k -bufsize 64k -f flv out.flv
[19:47] <llogan> ChocolateArmpits: if you're too lazy to test then ask on the ffmpeg-user mailing list.
[19:48] <ChocolateArmpits> llogan, I'm not lazy, I'm at home so don't have access to my workstation or the source material I will be doing this on
[20:13] <wodim> how can I read the contents of a dvd_nav_packet stream?
[20:17] <YuGiOhJCJ> llogan, and so what it means that I don't get xruns if I encode the audio only?
[20:19] <llogan> YuGiOhJCJ: http://trac.ffmpeg.org/ticket/615
[20:23] <YuGiOhJCJ> yes I have already read it and the "cehoyos" solution gives me "ALSA buffer xrun" too
[20:24] <YuGiOhJCJ> The command is: ffmpeg -f x11grab -r 25 -s 288x216 -i :0.0 -f alsa -i default -strict -2 -acodec aac -vcodec mpeg4 -y rec.mkv
[20:28] <YuGiOhJCJ> llogan, the problem is the same with this command than with my first command: when the output is a local file I got no "ALSA buffer xrun" messages but when the output is over the network then I got these messages.
[20:29] <llogan> does using "-threads 1" reduce or increase the xruns?
[20:29] <llogan> is your output bitrate faster than your bandwidth?
[20:29] <YuGiOhJCJ> when I read /proc/cpuinfo, I see I have only 1 core
[20:29] <YuGiOhJCJ> threads is for using more core isn't it ?
[20:30] <llogan> referring to your console output will indicate the number of threads that libx264 automatically allocates
[20:30] <YuGiOhJCJ> no my bandwith is ~100kB I have tested with the iftop command which is very useful
[20:31] <llogan> or you can try using two ffmpeg processes: one each for capturing video and audio and then somehow use a third to mux the outputs.
[20:31] <llogan> i'm just guessing here which is probably fairly obvious
[20:31] <YuGiOhJCJ> my last command: ffmpeg -f x11grab -r 25 -s 288x216 -i :0.0 -f alsa -i default -strict -2 -acodec aac -vcodec mpeg4 -threads 1 -y rec.mkv
[20:32] <YuGiOhJCJ> and I got these "ALSA buffer xrun" messages when I am on an NFS share but not if I am in a local directory like "/tmp"
[20:32] <llogan> i was referring to libx264, not mpeg4, which is probably not what you wanted in the first place
[20:32] <llogan> i don't know.
[20:33] <YuGiOhJCJ> ok I try with the first (that I prefer)
[20:34] <YuGiOhJCJ> my last command is: ffmpeg -y -f alsa -i default -f x11grab -r 10 -s 640x480 -async 1 -i :0.0 -strict -2 -c:a aac -c:v libx264 -pix_fmt yuv420p -preset ultrafast -s 640x480 -threads 1 -ar 44100 -b:a 64k -b:v 64k -bufsize 64k -f flv out.flv
[20:34] <YuGiOhJCJ> (threads is 1 instead of 0)
[20:35] <YuGiOhJCJ> and I got these "ALSA buffer xrun" messages when I am on an NFS share but not if I am in a local directory like "/tmp"
[20:36] <YuGiOhJCJ> This solution of using two ffmpeg processes could be the solution (and the third to mux the outputs)... Is it difficult to do?
[20:38] <llogan> not with "local" files that can be remuxed after they are done encoding
[20:47] <YuGiOhJCJ> ah ok but my final objective is to stream on twitch.tv... As I got these "ALSA buffer xrun" messages, I try to find the reason by changing the output to local files. But if it works only for thoses files it is not very interesting for me
[20:48] <YuGiOhJCJ> (in fact I can already avoid these messages by changing my current working directory from "/home" that is a NFS share to "/tmp")
[20:48] <YuGiOhJCJ> but for the stream, I have not this choice
[20:50] <YuGiOhJCJ> I am wondering why working over the network makes appeared these "ALSA buffer xrun" messages... Probably because it is slower.
[20:52] <YuGiOhJCJ> Do you think I should create a ticket for this problem?
[20:56] <YuGiOhJCJ> 64 kbit/s is a very ridiculous bitrate and should work over the network without any problem
[20:59] <bmhm> does WinTV-HVR-950Q has a hardware encoder, i.e. does it output an mpeg stream?
[22:17] <__raven> rtmp to ustream drops framerate extremely at 2mbit any experience with that?
[22:28] <BtbN> How do i remove subtitles when transcoding with the ffmpeg cli util?
[22:56] <kutemo> BtbN, use "-sn" to disable subtitles.
[22:57] <BtbN> ah, that's even better than the map solution i cam up with
[23:55] <rufsketch1> hello everyone
[23:56] <rufsketch1> I'm trying to encode multiple files into a mosaic of video
[23:56] <rufsketch1> however, the files are still being generated while I do this.
[23:56] <rufsketch1> and so ffmpeg runs to the end and then dies with the error [h264 @ 0x3051440] no frame!
[23:57] <rufsketch1> how can I make ffmpeg either wait for the next frame or specify a limit on how many frames ffmpeg is allowed to encode per second.
[23:57] <rufsketch1> I've tried using -re to tell it to encode at the speed of the input
[23:58] <rufsketch1> and that does slow the encoding speed down. but not to the correct 30 fps
[23:58] <rufsketch1> it brings it down to 60fps
[00:00] <rufsketch1> relaxed: http://pastebin.com/raw.php?i=5HwTLXZk
[00:00] --- Thu Feb 13 2014


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