[Ffmpeg-devel-irc] ffmpeg.log.20140829

burek burek021 at gmail.com
Sat Aug 30 02:05:01 CEST 2014


[00:13] <llogan> lkiesow: i've removed and copyedited some of his stuff. scatterbrained.
[00:41] <peshalto> would ffmpeg be the right tool if I want to create a one-frame video from a still image, matching the format of this video?
[00:41] <peshalto> http://pastebin.com/KkvAtYVy
[00:41] <peshalto> why do you want to create a one-frame video
[00:42] <peshalto> I dont, really, but Ill tell you why. Because what I really want to do is prepend one image to a video.
[00:42] <peshalto> anyone know how to do that with ffmpeg?
[00:42] <c_14> Just concat the image to the video?
[00:43] <c_14> https://trac.ffmpeg.org/wiki/How%20to%20concatenate%20(join,%20merge)%20media%20files
[00:43] <peshalto> yes I tried that
[00:43] <peshalto> (sort of)
[00:44] <peshalto> the input types dont match what I have, and I dont know how to change those command lines to match what I have
[00:44] <llogan> you can attempt make a 1 frame movie and then you can use the concat demuxer if you want to attempt to avoid encoding the "main" video, or use the concat filter if you want to encode everything
[00:44] <llogan> which do you prefer?
[00:44] <peshalto> Id like to avoid decoding/encoding& would prefer just passing stuff through as raw as possible
[00:47] <llogan> and you only want one frame? or do you mean you just want the image to appear for a certain duration?
[00:48] <peshalto> llogan: the ultimate purpose is to have it be the image that is displayed as a thumbnail by the OS, when browing the file system in a GUI
[00:48] <peshalto> so one frame should be enough
[00:48] <peshalto> obviously this assumes the OS chooses the first frame as the thumbnail. if it doesnt, Ill have to look for another approach.
[00:49] <llogan> the OS automatically chooses the first frame as the thumbnail? that would be boring for most movies.
[00:49] <peshalto> remarkably, thats what they seem to do, yes
[00:50] <peshalto> anyway it works for my purposes
[00:50] <peshalto> can I use ffmpeg for creating a one-frame video from a still?
[00:52] <peshalto> using c_14s technique I get the still image for the duration of the video
[00:52] <peshalto> and it wont open with QuickTime, although VLC opens it
[00:54] <c_14> peshalto: just use the image as the input file with -r 1 and then output to whatever you want
[00:54] <peshalto> and the bitrate went from 17886 to 739 kbs
[00:55] <peshalto> c_14: just use which command line options exactly?
[00:56] <peshalto> Theres also an FAQ entry on this, sort of, but the code produced errors, and when I got past those, a corrupted file
[00:56] <peshalto> but then, I probably just dont know what settings to use for that ffprobe output
[00:56] <peshalto> (ffprobe output in pastebin)
[00:57] <c_14> ffmpeg -r 1 -i image -c:v libx264 -pix_fmt yuv420p -vf 'colormatrix=[srccolormatrix]:bt709,scale=1280x720,fps=119.99' out.mov
[00:58] <c_14> something like that should do it or at least get you close
[00:58] <c_14> You might not need the scale, and the [srccolormatrix] needs to be replaced with the images colorspace.
[00:58] <llogan> and you need audio too, which can be generated with "aevalsrc=0"
[01:00] <c_14> Ah, I'm just reading that you can use the scale filter to set the output colormatrix.
[01:00] <c_14> https://ffmpeg.org/ffmpeg-filters.html#scale-1
[01:01] <llogan> i didn't know that and i stare at scale all day
[01:03] <peshalto> whoa thanks
[01:03] <peshalto> where do I put that aevalsrc=0 ? tried putting it after an -i and got a no such file or directory error
[01:04] <c_14> either -af or -f lavfi -i
[01:06] <peshalto> [Parsed_colormatrix_0 @ 0x7fd049501f20] Unspecified destination color space,
[01:06] <peshalto> then
[01:06] <peshalto> [AVFilterGraph @ 0x7fd049501c00] Error initializing filter 'colormatrix' with args ''
[01:06] <c_14> What's your current complete command?
[01:06] <peshalto> error opening filters
[01:07] <peshalto> ffmpeg -f lavfi -i "aevalsrc=0" -r 1 -i thumbnail.png -c:v libx264 -pix_fmt yuv420p -vf 'colormatrix=[srccolormatrix]:bt709,scale=1280x720,fps=119.99' out.mov
[01:07] <c_14> eh, you were supposed to replace everything in the [] with the source colormatrix of the png
[01:08] <peshalto> oh shit where s my input movie&
[01:08] <peshalto> is this only for the first step, making the .mov file from the still?
[01:08] <c_14> ye
[01:09] <Neppy> hmm... any way to get more info on what happened when ffmpeg says "input/output error"?
[01:09] <peshalto> where can I get that srccolormatrix?
[01:10] <c_14> peshalto: maybe drop the colormatrix filter and just use the out_color_matrix option of the scale filter
[01:10] <peshalto> doing man ffprobe now...
[01:10] <c_14> Neppy: input/output error is usually os-side
[01:10] <Neppy> hm
[01:11] <llogan> peshalto: also you'll need "-profile:v high"
[01:11] <peshalto> so& vfbt709,scale=out_color_matrix:1280x720 like that?
[01:11] <peshalto> + space
[01:11] <Neppy> can i have it keep going even when that error happens?
[01:13] <c_14> Neppy: that error means that ffmpeg can no longer write output data, continuing would be extremely unproductive
[01:14] <peshalto> llogan: in what position?
[01:14] <c_14> peshalto: as an output option
[01:14] <Neppy> hm..
[01:14] <Neppy> thats annoying ^^"
[01:15] <peshalto> no such filter: out_color_matrix
[01:15] <peshalto> ffmpeg -f lavfi -i "aevalsrc=0" -r 1 -i thumbnail.png -c:v libx264 -pix_fmt yuv420p -vf 'out_color_matrix,bt709,scale=1280x720,fps=119.99' -profile:v high out.mov
[01:15] <Neppy> so the only thing i can do is restart the encoding then?
[01:15] <peshalto> or maybe it should be colormatrix=out_color_matrix
[01:16] <c_14> peshalto: scale=w=1280:h=720:out_color_matrix=bt709
[01:18] <peshalto> heh ok now running without errors
[01:18] <peshalto> but
[01:18] <peshalto> still running& and running&.
[01:18] <c_14> Add a duration switch to the aevalsrc or add -shortest as an output option.
[01:19] <peshalto> 3 hours long when I Ctrl-Ced it
[01:19] <c_14> 3 hours of silent audio and 1 frame of video
[01:19] <peshalto> heh
[01:19] <c_14> just what you've always wanted
[01:20] <peshalto> yeah it was black after one frame& call hollywood!
[01:21] <llogan> ffmpeg -framerate 119.99 -i input -filter_complex "aevalsrc=0[a]" -map 0:v -map "[a]" -s 1280x720 -pix_fmt yuv420p -c:v libx264 -x264opts colormatrix=bt709 -profile:v high -c:a aac -strict -2 -shortest output.mov
[01:22] <llogan> i wanted to use format and scale instead of -pix_fmt and -s but i'm too hungover to get it to only do one frame
[01:23] <llogan> and -vframe won't include the audio
[01:23] <peshalto> ok so then I put the output filename along with my movie-to-be-prefixed.mov filename in mylist.txt, and did: ffmpeg -f concat -i mylist.txt -c copy output.mov
[01:23] <peshalto> and got corrupted output similar to what I got when I tried the faq entry
[01:24] <peshalto> still it seems Im getting closer
[01:24] <llogan> i don't know if using output.mov for an input and output.mov for the output will grok
[01:24] <peshalto> ffmpeg -f lavfi -i "aevalsrc=0" -r 1 -i thumbnail.png -c:v libx264 -pix_fmt yuv420p -vf 'scale=w=1280:h=720:out_color_matrix=bt709,fps=119.99' -profile:v high -shortest thumbnail.mov
[01:24] <peshalto> comparing mine with llogans now
[01:25] <llogan> several ways to flog a horse or kick a cat i guess
[01:25] <peshalto> I get an error with that one
[01:25] <llogan> workedforme
[01:26] <peshalto> whats input in your example? mine is a png file
[01:26] <llogan> your input file name
[01:26] <peshalto> it worked for me too but did you try the next step, prepending it to a video file?
[01:26] <peshalto> thats the part that doesnt work for me
[01:27] <peshalto> well I mean c_14s worked for me
[01:27] <peshalto> [concat @ 0x7fc16b800000] DTS 28 < 279 out of order
[01:27] <peshalto> [mov @ 0x7fc16b825e00] Invalid DTS: 379 PTS: 28 in output stream 0:0
[01:27] <peshalto> [mov @ 0x7fc16b825e00] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 279 >= NOPTS
[01:27] <llogan> no. too lazy to try.
[01:27] <peshalto> av_interleaved_write_frame(): Invalid argument
[01:27] <peshalto> yeah I have something not matched pu
[01:27] <peshalto> up*
[01:31] <llogan> peshalto: maybe it will still play fine
[01:32] <llogan> oh nevermind, i missed some of your output
[01:32] <llogan> anyway, it seemed to work for me
[01:33] <peshalto> the input file was 30MB, the output (concatenated) file is 9.7k
[01:35] <peshalto> the other command (pasted above) gave me a reasonable output file size, but the file system cant make a thumbnail out of it, and VLC thinks its 1 second long (should be 13 secs long)
[01:36] <peshalto> I guess what I need to learn is how to read the ffprobe output, and translate that into the right ffmpeg input
[01:40] <peshalto> a killer youtube tutorial would be someone going through a screen full of ffprobe output and explaining all the stuff bit by bit
[01:41] <llogan> peshalto: here's one you can test http://avmule.com/junk/peshalto.mov
[01:42] <llogan> not exactly the same as yours, but at least it will see if the OS chooses 1st frame
[01:42] <llogan> or see if it actually plays correctly in your players of choice
[01:43] <peshalto> nice
[01:43] <peshalto> yeah, first frame, and it plays
[01:44] <peshalto> assuming the first frame is the one with the 0 on it
[01:45] <llogan> no. it's a screenshot from the 1986 NES game "Pro Wrestling"
[01:45] <llogan> "a winner is you"
[01:46] <peshalto> ah right
[01:46] <peshalto> yeah it does NOT show the first frame
[01:46] <llogan> http://knowyourmeme.com/memes/a-winner-is-you (although no sarcasm was meant with this image choice)
[01:47] <peshalto> Ill have to play with it to see what its doing. maybe be a heuristic based on what it finds in the file. I wonder if theres any metadata you can set to control which frame is used.
[01:48] <peshalto> gotta go soon, will report back if I figure this out
[01:49] <llogan> peshalto: http://avmule.com/junk/clock.mov
[01:50] <llogan> i guess "clock" is not an accurate name, but it may allow you to see what frame it chooses (if it always chooses a certain frame)
[01:51] <peshalto> cool& thanks llogan and c_14
[01:51] <peshalto> later
[01:51] <llogan> or maybe it just chooses a certain dura...........poof
[02:31] <diegoviola> i'm trying to encode some mp4 video file to webm, but i want to preserve the same video quality, what option should I look for?
[03:12] <diegoviola> any ideas?
[03:14] <diegoviola> how do i find out a list of presets?
[03:27] <radleader> i'm exporting a video from after effects that contains alpha data that i want to use ffmpeg filter graph to composit together with a series of PNG images (that show through the alpha) then produce an mpeg output - what format would be lowest computational overhead for ffmpeg for the input alpha video
[03:28] <radleader> should i use h264 and have an extra video file with the alpha mask in it?
[03:28] <radleader> should i use an avi containerand just keep it uncompressed
[03:28] <radleader> not sure what the best plan here is
[03:41] <jorb> http://superuser.com/questions/804508/some-transcoded-streams-delayed-or-not-playable-from-ffmpeg
[05:34] <myubuntu> how to mp4's indexs from tail to head?
[05:47] <myubuntu> how to move mp4's indexs from tail to head?
[06:06] <relaxed> myubuntu: ffmpeg -i input -movflags faststart output.mp4
[06:37] <hanshenrik> where can i buy a cat?
[06:46] <ghospich> you can download absolutely free (as freedom and beer) cat which comes with GNU coreutils.
[06:48] <hanshenrik> oh ok, but i already have the source and gcc
[06:49] <hanshenrik> cat*
[06:49] <hanshenrik> so.. i want to grab the first 4 minutes and 10 seconds off a video, losslessy, umm, ffmpeg -i foo -c:v:copy -c:a:copy bar      ?
[06:51] <rav0> -t duration https://www.ffmpeg.org/ffmpeg.html
[06:55] <hanshenrik> ffmpeg -i foo -c:v:copy -c:a:copy -t 00:04:10 bar  then, look about right?
[06:55] <hanshenrik> thanks btw
[06:55] <rav0> yep
[06:56] <rav0> if there isn't a keyframe where you specified, ffmpeg will cut at the next keyframe. if your content has a visible cut, there is likely a keyframe nearby, you can try specifying 0:04:09 to get what you want
[06:57] <hanshenrik> Unknown encoder '-c:a:copy' , and i am using a 2014 build :s
[06:58] <relaxed> -c:a copy
[06:58] <hanshenrik> oh,
[06:59] <rav0> for video also
[06:59] <rav0> or just -c copy
[06:59] <hanshenrik> ok that worked great, thanks guys
[07:00] <hanshenrik> though i must say, i prefer the old (deprecated? remvoed?) -acodec / -vcodec :p
[07:04] <hanshenrik> so.. about 1am today, went down on my gf... she must have been very relaxed, cause she fell asleep
[07:41] <myubuntu> relaxed: thanks.
[07:42] <myubuntu> test
[07:43] <relaxed> microphone check
[07:43] <relaxed> you're welcome
[09:26] <ewa> hi
[09:26] <ewa> i have a problem with micro on Debian
[09:26] <ewa> i need to record a video with ffmpeg but using external microphone not front mic in my notebook
[09:26] <ewa> how can I mute front mic and use external mic?
[09:27] <ewa> right now I record with both of them at the same time so the quality is bad
[10:03] <K4T> is it possible with ffmpeg to restream multicast input? As input I would like to have multicast ip address: -i udp://239.239.1.1:4321
[10:03] <K4T> for example
[10:58] <BillyZane> is it possible to setup a server on a computer that does not have X installed and broadcast a video without the audio or video playing locally?
[11:06] <myubuntu_> ls
[11:41] <Speed``> i just got my ducky shine 3 :)
[11:41] <Speed``> oops wrong channel
[11:43] <pron> gz
[12:50] <pmarty> do ffmpeg/ffplay read any configuration files by default? i would like to put -hide_banner option there.
[13:05] <pmarty> then i might just add shell alias ffmpeg='ffmpeg -hide_banner'
[13:20] <Nopik> hi, I'm having small problem with ffserver, it does not restart ffmpeg (Launch config line) after they exit.. anybody had such problem, how to fix it?
[14:06] <KAT_> which CPU is the best for ffmpeg? I should look on to amount of cores a frequency?
[14:06] <KAT_> cores or frequency*
[14:45] <vlatkozelka> hi , is it possible to add a new "layer" once streaming has started ? for example if i need to add some "urgent news" at the bottom in real time . I know this can be done if u know u gonna add a video from the beginning ... but is it possible in real time after the streaming started ?
[14:58] <KAT_> vlatkozelka, you should use something like CasparCG to do thing like this
[15:32] <jorb> anyone have a sec to try and answer this question? http://superuser.com/questions/804508/some-transcoded-streams-delayed-or-not-playable-from-ffmpeg
[15:32] <jorb> or just... comment on it here w/e
[15:37] <jorb> or just tell me i am lazy for not typing the question into irc
[15:55] <jorb> http://pastebin.com/2uCuFLFB
[16:07] <disruptive> hi all
[16:08] <disruptive> Im doing some searching around and didnt find much, but is there anything along the lines of FEC or some sort of error correction on UDP streams?
[16:08] <disruptive> I see that there is some error concealment messages when using rtsp over tcp
[16:09] <jnvsor> UDP has nothing at all, it's just data. The only reason it's used is because while TCP has error correction it also has throttling built in
[16:10] <jnvsor> If you want error correction you'll have to DIY or have it built into whatever protocol you run over UDP
[16:10] <disruptive> thanks jnvsor, I understand that UDP just spits whatever. Is there any sort of server-client already available with ffmpeg implementations that have some sort of error recovery in the mix?
[16:10] <disruptive> I see
[16:10] <jnvsor> Which protocol are you using to transfer?
[16:10] <jnvsor> UDP by itself doesn't really do anything unless you have a protocol for it already
[16:11] <disruptive> if Im doing it right, Im using multicasting
[16:12] <jnvsor> So, mpegts format?
[16:12] <disruptive> its h.264 in rtp?
[16:13] <jnvsor> Hmm, never used rtp sorry
[16:14] <disruptive> in the case of mpegts would there be some light in this question?
[16:15] <jnvsor> No idea, I just noticed it was the example code for all the ffmpeg multicast info I could google :P
[16:15] <disruptive> lol
[16:28] <disruptive> thanks again for your replies jnvsor
[16:37] <jorb> ..anyone seen an issue with video files jamming up ffmpeg streaming to stdout?
[16:37] <jorb> http://pastebin.com/2uCuFLFB
[16:38] <jorb> err audio files with images in the container
[16:39] <jorb> http://superuser.com/questions/804508/some-transcoded-streams-delayed-or-not-playable-from-ffmpeg
[16:39] <disruptive> Ive ran by this before: http://lists.mplayerhq.hu/pipermail/mplayer-users/2011-August/083163.html
[16:39] <klaxa|work> i never encountered that problem
[16:39] <disruptive> but that was back in 2011
[16:40] <jorb> well mplayer runs it OK eventually
[16:40] <jorb> but other players will just drop the streams because they are "unrecognized"
[16:40] <klaxa|work> can you try writing it to a file and play it with a different player then? what formats do you use? is it always mp3?
[16:41] <jorb> everything is transcoded to mp3 by default
[16:41] <jorb> yes, writing toa file removes the issue..
[16:42] <jorb> i'm pretty sure when i was running Ubuntu 12.04 this was not an issue too
[16:43] <klaxa|work> that is weird indeed, can the players play it like this: cat file.mp3 | player - ?
[16:44] <jorb> yes
[16:44] <jorb> it is something that ffmpeg is doing presumably
[16:44] <jorb> i am guessing just pading 000000000000000 or something
[16:45] <jorb> kind of a minor issue anyway, but seems like others would have run into it
[16:46] <klaxa|work> can you try to write to a file using a pipe and compare that with the file produced without a pipe?
[16:47] <jorb> yeah, it works fine if i pipe it to a file
[16:47] <jorb> the problem is definitely rooted in the audio files themselves though
[16:47] <jorb> just cause a bug in ffmpeg maybe...
[16:48] <jorb> something crappy / non standard in the container maybe
[16:48] <klaxa|work> does it work with other files?
[16:49] <jorb> most files run fine, just particular ones have an issue
[16:49] <jorb> those with album art is one category
[16:53] <klaxa|work> maybe try adding "-map 0:a" to the ffmpeg command
[16:53] <klaxa|work> ffmpeg tries to put in the cover art into the audio-file, do you want that even?
[16:54] <jorb> yeah, kind of nice
[16:54] <jorb> haha
[16:54] <jorb> does that front load the audio?
[16:54] <klaxa|work> it tells ffmpeg to only use the audio from the first input
[16:55] <jorb> yeah, same result with the -vn option i believe
[16:55] <jorb> does work, but no album art for the player
[16:59] <klaxa|work> i can't find documentation on where id3 metadata is stored
[17:00] <klaxa|work> what i can imagine is that the metadata is placed at the end of the file with pointers to it at the beginning or something
[17:04] <jorb> yeah that would definitely be an issue.. i'll study the troublesome files some more
[17:04] <jorb> seeing some folks with the issue also from their forum
[17:04] <jorb> http://forum.subsonic.org/forum/viewtopic.php?f=2&t=14644
[17:05] <klaxa|work> turns out id3v1 does it like that, id3v2 does not
[17:21] <kaotiko> hi
[17:26] <jorb> fuck can't get by the spam detection on forum.subsonic.org lol
[17:31] <jorb> the question was what year was the Battle of Hastings
[17:34] <mifritscher> hi
[17:35] <mifritscher> how can I set the mtu for udp streaming?
[18:29] <mifritscher> In case somebody answered about the mtu-question: sorry, had connection problems
[18:37] <ac_slater_> hey all. I'm doing something like `ffmpeg -i hd.mpeg -f rtp rtp://127.0.0.1:6666 > test.sdp` and `ffplay test.sdp` .... this works but the video quality is super low on the receiver side. I tried setting bitrate to ensure it was at least what ffprobe detected. Any clues?
[19:28] <ac_slater_> Any hints how to take an mp4 (h264) with video and audio and reencode it to mpegts?
[19:28] <ac_slater_> oh, wait, I got it, really simple
[19:29] <Mavrik> just remux it with -codec copy
[19:30] <Mavrik> no need to reencode
[19:31] <ac_slater_> Mavrik: right!
[19:32] <ac_slater_> Mavrik: apparently, 'h.264 bitstream malformed... '
[19:33] <ac_slater_> Mavrik: ah it even gave me a hint, `-bsf h264_mp4toannexb`
[19:33] <Mavrik> mhm :)
[19:38] <mifritscher> hi
[19:45] <ac_slater_> Mavrik: it's also very frustrating that ffmpeg's rtp layer only supports one stream per session. Kind of defeats the purpose of it
[19:48] <Mavrik> ac_slater_, I avoid RTP like the plague
[19:48] <Mavrik> it's a shitty format that rarely works on any half complicated environment
[19:49] <ac_slater_> Mavrik: it is really crappy. But sadly, I need it.
[19:50] <ac_slater_> Mavrik: I've been using ffmpeg for mux/demux and live555 for delivery... live555 is a mess, and nothing from it plays on anything that doesnt use live555 for recieving - ie, not standard compliant
[19:51] <Mavrik> mhm
[19:51] <Mavrik> we just gave money to wowza at the end
[19:52] <ac_slater_> Mavrik: does wowza work on ARM? Linux?
[19:52] <ac_slater_> Mavrik: ah hold on, looking at the site... at first glance it's confusing
[19:52] <Mavrik> ac_slater_, no idea
[19:53] <Mavrik> I mean, we did use it on Linux :)
[19:53] <Mavrik> but we had a x86 cluster
[19:57] <ac_slater_> Mavrik: yea :( I'll be streaming this stuff from a 733mhz ARM
[19:57] <Mavrik> ah, good luck :)
[19:57] <ac_slater_> (not the ras-pi ... but an SoC)
[19:57] <ac_slater_> Mavrik: yea ... ffmpeg's rtp stuff is just lacking, I'll ditch it and start over
[19:57] <ac_slater_> thanks!@
[19:58] <Mavrik> why not use something sane like MPEG2-TS over UDP, RTSP which is slightly better or something like that?
[20:09] <ac_slater_> Mavrik: right, I've moved to RTSP and it seems to work ... I just dont need to VCR-like features or the TCP requirement.
[20:09] <ac_slater_> MPEG2-TS is ok only if I can have h.264 video, which it looks possible, maybe not via ffmpeg though
[20:12] <Mavrik> ac_slater_, of course its possible
[20:12] <Mavrik> MPEG2-TS is what we use for IP-TV distribution, DVB-T and DVB-S
[20:13] <Mavrik> and also in US for broadcasting :)
[20:13] <Mavrik> it's just that there was no need for update in MPEG4 standard so there was no MPEG4-TS
[20:13] <ac_slater_> Mavrik: that makes sense. I just know not to make assumptions with container formats ;) Though , TS == transport stream, so it's prob different
[20:13] <ac_slater_> I see.
[20:13] <ac_slater_> interesting
[20:14] <Mavrik> anyway, it's a format made for streaming and usually works rather well over UDP
[20:16] <ac_slater_> Mavrik: what about jitter compensation, redelivery, etc... sure, it's UDP and therefore simple, but RTP is does that ... at least the standard says it does, I cant find a solid implementation
[20:16] <Mavrik> you practically never want redelivery in a streaming video
[20:16] <Mavrik> (and you can also always do tcp streaming)
[20:16] <ac_slater_> Mavrik: unless it's a simple 1500byte slice
[20:17] <ac_slater_> Mavrik: RTP seems convincing, but yes, it does produce latency with redeliveries. Thankfully, most implementations dont implement redelivery
[20:17] <Mavrik> having redelivery on any transmission is just asking for trouble
[20:17] <Mavrik> if the packet is gone, it's gone
[20:17] <ac_slater_> I agree.
[20:18] <Mavrik> resending a packet which should be already played will just clog your buffers and network
[20:18] <ac_slater_> resulting in latent video, which is lame
[20:18] <ac_slater_> I just need RTP for it's standardization.
[20:18] <Mavrik> unless you have a huge buffer... but most of applications have shown that using TCP is just a source of trouble on network layer
[20:18] <ac_slater_> ie - most things play it
[20:18] <ac_slater_> right, udp is the way to go
[20:19] <ac_slater_> I avoided mpeg2-ts for a long time, since RTP is everywhere these days ... at least in my target audience
[20:21] <ac_slater_> I still havent messed with oRTP, etc... mainly because most implementations dont handle packetization of video, they are intended for audio really.
[20:22] <ac_slater_> I need h.264 and a specialized data format which I've written an encoder/decoder for ... MPEG2TS is my container format already since it allows an arbitrary data stream. I guess it wouldnt be terrible to test MPEG2-TS delivery
[23:39] <ac_slater_> I wonder how much it'll take to add support for multiple streams to ffmpeg
[23:39] <ac_slater_> (/ libavformat)
[23:41] <klaxa> depending on the definition of "multiple streams" it already supports multiple streams
[23:41] <klaxa> what do you define as "one stream" exactly?
[23:50] <ac_slater_> klaxa: I see. The RFC has all of that in there... that is, RTCP will do some synching
[00:00] --- Sat Aug 30 2014


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