[Ffmpeg-devel-irc] ffmpeg.log.20161126

[burek]

[00:02:12 CET] <furq> markvandenborre: what does ffprobe -show_streams say
[00:19:15 CET] <markvandenborre> furq: checking
[00:23:19 CET] <markvandenborre> furq: https://gist.github.com/markvdb/eff3ab32d72dccbd42ed596b818ff8de
[00:23:50 CET] <markvandenborre> (note that I probably made some really silly codec settings mistakes)
[00:27:26 CET] <markvandenborre> furq: the video gets generated by https://github.com/FOSDEM/video/blob/master/software/ansible/playbooks/roles/voctohost/files/scripts/sink-streaming.sh
[00:28:06 CET] <markvandenborre> then from the flv coming out of the streaming, it gets reprocessed into an mp4 container with the command
[00:28:55 CET] <furq> are you getting errors other than non-monotonous dts
[00:29:00 CET] <furq> you can usually ignore that one iirc
[00:29:21 CET] <furq> and i think unsafe filename is just ffmpeg being overzealous
[00:29:29 CET] <markvandenborre> yes, seems so
[00:29:35 CET] <markvandenborre> ffmpeg -y -i $path -codec copy -movflags +faststart $dirname/$basename.mp4
[00:29:50 CET] <markvandenborre> is fairly generic also
[00:30:01 CET] <markvandenborre> nothing much there that could cause trouble I guess
[00:30:14 CET] <furq> if the video plays back correctly you can just ignore it i think
[00:30:25 CET] <markvandenborre> the problem is it does not play back correctly of course
[00:31:18 CET] <markvandenborre> these are not private videos, they're CC licensed, so if anyone wants a closer look
[00:31:48 CET] <markvandenborre> I could just push them somewhere publicly accessible
[00:32:28 CET] <markvandenborre> the preroll is a 720p jpeg basicly
[00:32:52 CET] <markvandenborre> and an example of a video as generated by our encoders is at
[00:34:30 CET] <markvandenborre> http://glasno.st/fosdem/video.mp4
[00:34:54 CET] <markvandenborre> let me check the errors I get when encoding again
[00:41:14 CET] <markvandenborre> furq: it seems I could use the concat protocol, even if the wiki says it is a bit obsolete
[00:42:52 CET] <furq> yeah i just tried remuxing that video to ts and concat worked fine
[00:43:01 CET] <furq> the demuxer, i didn't try the protocol although that should work fine too
[00:43:13 CET] <furq> that's a bunch of additional steps though
[00:46:33 CET] <markvandenborre> let me also upload the image file with silent audio
[00:47:18 CET] <markvandenborre> http://glasno.st/fosdem/prerollsilentaudio.mp4
[00:48:28 CET] <markvandenborre> I'm trying to document stuff a bit around https://github.com/FOSDEM/video/wiki/Ffmpeg:-concatenating-preroll-and-postroll-without-reencoding
[00:48:48 CET] <markvandenborre> seems like the only option would be remuxing to mpeg ts
[00:49:05 CET] <markvandenborre> or do you see any other option?
[00:51:06 CET] <furq> http://vpaste.net/IG2q4
[00:51:11 CET] <furq> i did something like that
[00:51:25 CET] <furq> concat with codec copying has always been a bit flaky, i don't know the internals well enough to suggest anything else
[00:51:30 CET] <furq> i normally just work around it when it breaks
[00:52:36 CET] <markvandenborre> thx for the hints
[00:52:53 CET] <furq> the concat filter is much  more reliable but i guess you don't want to reencode
[00:56:07 CET] <markvandenborre> furq: we have > 500 hours of talks
[00:56:21 CET] <markvandenborre> and we want to have them online asap when the conference is still running
[00:56:50 CET] <markvandenborre> and a few other requirements that make us really  not want toe reencode indeed
[00:57:20 CET] <markvandenborre> in fact, we have a perfect ffmpeg script except for avoiding the reencoding
[00:58:04 CET] <markvandenborre> if we avoid the reencode, we avoid lots of complexities in other places
[00:58:22 CET] <markvandenborre> so if that means an ugly hack with fifos or temporary files, so be it I guess
[00:59:18 CET] <markvandenborre> I will have another look one of the coming days, so if you have any inspiration come up about ways to avoid the mp4 to ts remux, you'll know where to find me :-)
[00:59:21 CET] <markvandenborre> thx
[03:20:20 CET] <mundus2018> Im looking for help converting a .dsf file to .flac
[03:20:42 CET] <mundus2018> the dsf has an 88200Hz bitrate
[05:29:26 CET] <tomed> would upgrading ddr4 see improvement in ffmpeg
[11:08:06 CET] <Se7en> Hwllo. I have a possible bug rerport to file. I am not sure though.
[11:08:50 CET] <Se7en> When attempting to play a file remotely (over an ftp:// URI) on MPV I was unable to. They report this is an issue with FFmpeg as the issue is replicated with ffplay
[11:08:53 CET] <Se7en> The file was an Opus
[11:09:07 CET] <Se7en> The person in the MPV chatroom was able to replicate it
[11:09:15 CET] <Se7en> How do I generate the debugger output?
[11:10:52 CET] <Se7en> If someone is here I can directly link the file
[11:13:38 CET] <Se7en> Other files are opening so it's only the opus
[11:22:55 CET] <durandal_1707> Se7en: if you try directly it also happens?
[11:23:00 CET] <Se7en> Yes
[11:23:05 CET] <Se7en> it can be replicated in ffplay
[11:23:24 CET] <Se7en> The file is stupid, but it caused me to find the error in opus
[11:23:26 CET] <Se7en> ftp://joelixny.ddns.net/Moon%20Man/Misc/MoonMan%20-%20The%20Real%20MoonMan-t4gjKYHYXnw.f251.opus
[11:23:54 CET] <Se7en> That stupid meme of the McDonald's moon guy singing the racist songs
[11:24:00 CET] <Se7en> But it brought me to discover the problem
[11:24:33 CET] <durandal_1707> you mean if you even download it?
[11:25:19 CET] <durandal_1707> I'm not right on computer but you can file bug report
[11:26:25 CET] <Se7en> Actually, I haven't trierd that yet. One moment
[11:26:51 CET] <Se7en> Downloading the file works fine, yeah
[11:26:56 CET] <Se7en> Only when accessing vorbis remotely
[11:26:59 CET] <Se7en> Other file types work
[14:06:42 CET] <BlackFox> I have bit of a weird question
[14:06:56 CET] <BlackFox> So there's a file with raw 264 stream, but seemingly there's also audio in that file
[14:07:31 CET] <BlackFox> Is there any way to see or split the actual raw 264 stream (which plays just fine) from the audio that is embedded in some sort of weird way
[14:07:46 CET] <techtopia> you want to demux it?
[14:08:16 CET] <techtopia> ffmpeg -i file.h264 -vn -sn -acodec copy file.wav
[14:08:30 CET] <techtopia> ffmpeg -i file.h264 -an -sn -vcodec copy file.h264
[14:08:44 CET] <techtopia> first will dump audio to wav second will dump video to h264
[14:08:52 CET] <techtopia> it's unlikely that it contains audio though
[14:08:53 CET] <BlackFox> Gonna try that (but so far it just seems that audio is encoded in some weird way)
[14:09:00 CET] <kerio> BlackFox: who said that there's audio in there?
[14:09:02 CET] <BlackFox> It does contain audio (I was puzzled myself)
[14:09:05 CET] <kerio> pastebin the output of ffprobe
[14:09:31 CET] <BlackFox> There is a proprietary and very badly made tool that can play these files with audio (and it plays just from a single file), but... yeah, one sec
[14:09:39 CET] <DeadSix27> BlackFox: do you have a audio file wiht the same name in the same folder?
[14:09:44 CET] <DeadSix27> just to get that out of the way
[14:09:53 CET] <techtopia> good thought DeadSix27
[14:10:14 CET] <BlackFox> DeadSix27, definitely no audio in the same folder, it's a good sanity check though
[14:10:18 CET] <DeadSix27> kk
[14:10:36 CET] <DeadSix27> (some players, considering we do not knwo which you used, just play the same-named audio along a video)
[14:10:46 CET] <BlackFox> I don't know which one I used myself
[14:11:05 CET] <BlackFox> It's literally "player.exe" and apparently came with some obscure dashcam someone had
[14:11:16 CET] <DeadSix27> but ye, paste the ffprobe output as kerio said.
[14:12:03 CET] <DeadSix27> (on pastebin*)
[14:12:32 CET] <BlackFox> http://pastebin.com/bWgDcVKH
[14:12:56 CET] <techtopia> there is no audio
[14:13:05 CET] <DeadSix27> seemingly
[14:13:11 CET] <kerio> :c
[14:13:20 CET] <kerio> well, it might be some weird raw format
[14:13:22 CET] <BlackFox> well yes, there can't be any audio in raw h264 stream, but somehow the player manages to play it given just one file
[14:13:32 CET] <kerio> idk
[14:13:33 CET] <BlackFox> so it's most definitely sticking audio somewhere unconventional
[14:13:34 CET] <furq> do you have an audio file with the same filename
[14:13:53 CET] <furq> mpc-hc will autoplay it if you do
[14:13:56 CET] <furq> maybe some other players as well
[14:14:01 CET] <DeadSix27> we furq, already mentioned that
[14:14:06 CET] <DeadSix27> furq, we**
[14:14:06 CET] <kerio> he's not using a real player
[14:14:10 CET] <furq> oh so you did
[14:14:11 CET] <kerio> it's some weird dashcam format
[14:14:30 CET] <DeadSix27> kerio: wow you can see that just by that?
[14:14:30 CET] <BlackFox> Only this proprietary thing from china with no name plays it
[14:14:46 CET] <furq> probably some godawful made-up shit then
[14:14:50 CET] <kerio> DeadSix27: yes, i can see that just by the fact that he said "it's literally player.exe and came with some obscure dashcam someone had"
[14:15:03 CET] <furq> there's no telling what the chinese will stuff into places it doesn't belong
[14:15:04 CET] <kerio> :^)
[14:15:05 CET] <DeadSix27> ohhh, didn't see that line :p
[14:15:15 CET] <BlackFox> I'm going to try demux video from this
[14:15:18 CET] <DeadSix27> I thought you just figured it out by the ffprobe output hah
[14:15:18 CET] <BlackFox> See if the files are different
[14:15:24 CET] <furq> it probably won't work with ffmpeg
[14:15:28 CET] <kerio> furq: why not
[14:15:29 CET] <furq> only one way to find out though
[14:15:30 CET] <BlackFox> It should possibly reveal proprietary extra bytes
[14:15:33 CET] <kerio> ffmpeg saw the video
[14:15:36 CET] <kerio> *ffprobe
[14:15:37 CET] <BlackFox> furq, ffmpeg will decode video fine
[14:15:48 CET] <BlackFox> and anything else that can eat raw 264 stream will play this (without audio)
[14:15:59 CET] <kerio> i bet it's chunks of h264 and chunks of some audio
[14:16:12 CET] <kerio> BlackFox: does this player.exe allow seeking?
[14:16:16 CET] <furq> i guess if the audio is just stuffed into NALUs then it might work
[14:16:31 CET] <kerio> furq: Invalid NAL unit 8, skipping.
[14:16:32 CET] <kerio> :o
[14:16:39 CET] <BlackFox> kerio, I'm not sure, I'll check (probably not)
[14:16:48 CET] <BlackFox> It's hard to say because these files are pretty tiny
[14:16:54 CET] <BlackFox> so it might be just seeking by playing them through
[14:17:03 CET] <kerio> BlackFox: any chance you can upload one somewhere?
[14:17:12 CET] <BlackFox> Yes
[14:17:15 CET] <furq> yeah i read the pastebin properly after saying it wouldn't work
[14:17:16 CET] <BlackFox> Give me like... 4 min
[14:23:29 CET] <BlackFox> Just checked, the player doesn't allow seeking, but it does. Aka if you seek, it freezes for a tiny while before it can play, so it probably just seeks through entire stream (which is expected)
[14:24:42 CET] <BlackFox> https://drive.google.com/file/d/0B69uOz7lkjebaDVrRXFmQ1lQd1k that should work
[14:25:28 CET] <BlackFox> bizzarely, the person who did the recording itself claims that they should have four audio channels in them
[14:25:42 CET] <kerio> well, mpv refuses to play it
[14:26:37 CET] <DeadSix27> mpc with lav plays it fine
[14:26:53 CET] <DeadSix27> mpv doesnt either here
[14:27:05 CET] <DeadSix27> however I have no audio in mpc
[14:27:06 CET] <BlackFox> http://i.imgur.com/2H8ibN3.png this is what kinda video is in it, just for a sanity check
[14:27:42 CET] <kerio> yeah i saw it
[14:27:45 CET] <DeadSix27> BlackFox: http://i.imgur.com/fWObfgA.png
[14:28:04 CET] <BlackFox> yeah, cause there can't be a proper audio stream in a raw video stream
[14:28:33 CET] <kerio> is it a real container that ffmpeg doesn't understand
[14:28:35 CET] <techtopia> moc and vlc won't play it
[14:28:38 CET] <kerio> or is it something awfully hacky
[14:28:42 CET] <techtopia> media info just sees a video stream
[14:28:44 CET] <BlackFox> this is not a container for sure
[14:28:46 CET] <kerio> like, the audio embedded in a raw h264 stream
[14:28:52 CET] <BlackFox> this is just a raw stream with probably embedded audio
[14:29:05 CET] <DeadSix27> thats odd ye, why didn't they just put audio alongside
[14:29:06 CET] <BlackFox> I'm not familiar with h264 format enough to tell
[14:29:11 CET] <DeadSix27> or use a proper container
[14:29:18 CET] <kerio> because china
[14:29:24 CET] <DeadSix27> :p
[14:30:41 CET] <DeadSix27> offtopic, BlackFox, are you using a dashcam as security camera?
[14:31:30 CET] <kerio> well i mean
[14:31:32 CET] <kerio> why not
[14:31:37 CET] <DeadSix27> i guess
[14:31:57 CET] <BlackFox> Nah
[14:31:58 CET] <DeadSix27> I use 3 logitech webcams as security cameras..
[14:32:10 CET] <DeadSix27> cuz cheap.
[14:32:25 CET] <BlackFox> it's a dedicated device that records 4 video channel from IP or analog cameras
[14:32:34 CET] <BlackFox> 4 video channels*
[14:32:57 CET] <BlackFox> so in theory, the file should contain four video tracks (although only one camera was connected at this time to that device) in some sort of a bizzare container-but-not-really
[14:32:59 CET] <BlackFox> but
[14:33:00 CET] <DeadSix27> either way, what was your initial question and did we solve your problem?
[14:33:39 CET] <BlackFox> well, the problem isn't solved (need to extract audio), but there's a backup plan
[14:33:50 CET] <DeadSix27> ah, right you actually did want the audio
[14:34:06 CET] <BlackFox> which is just taking literally audio out from the video recorder thing and plugging it into a line in of some computer
[14:34:18 CET] <BlackFox> and then just letting it sit there for like half a day while it dumps the audio :'D
[14:39:17 CET] <kerio> surely before doing that you'd just disassemble the .exe
[14:39:25 CET] <BlackFox> well
[14:39:35 CET] <BlackFox> no need to, just figure exports and imports of one DLL I think
[14:40:07 CET] <BlackFox> the player.exe is followed by three sets of DLL's: avcodec, a bunch of h264-related DLL's (a weird bunch at a glance), plus something that is cryptically called "streamreader.dll"
[14:40:28 CET] <DeadSix27> that last one sounds indeed interesting in this context
[14:40:29 CET] <BlackFox> honestly, based on my experience with chinese, if I *did* manage to find out who made this player.exe, asking them for a source code would be trivial
[14:41:16 CET] <BlackFox> there is no semblance of any about boxes, readme's or anything that would identify any brands or company names. Presumably I need to dig deeper into the files to find out who made it, but... it's not gonna be me sitting there for hours while the videorecorder is doing the thing
[14:41:30 CET] <BlackFox> so might as well go with the backup plan right away
[14:41:38 CET] <DeadSix27> googlign helped
[14:41:42 CET] <kerio> that is retarded
[14:41:45 CET] <DeadSix27> somewhat
[14:43:59 CET] <BlackFox> this is sorta video related, so we had some chinese-made DVB transmitters/receivers and wanted to feed custom data through them (use them as sort of a SDR)
[14:44:45 CET] <DeadSix27> is the player.exe called exactly that btw?
[14:44:48 CET] <DeadSix27> just out of couriosity
[14:45:16 CET] <BlackFox> the driver for the device was written by some non-chinese company (I guess whoever made the chip), but the actual interface part of the driver was a shoddy chinese thing
[14:46:01 CET] <BlackFox> it was having lots of issues, we asked them for a newer verison, they just sent us all sourcecode to their stuff
[14:46:13 CET] <BlackFox> I was not surprised at all to see the code quality
[14:46:47 CET] <kerio> was it shit?
[14:46:57 CET] <BlackFox> absolutely and utterly
[14:47:18 CET] <BlackFox> exceptions were used as a way to return successful indications
[14:49:33 CET] <BlackFox> also it had no actual error handling interface, all errors were dumped as text into msvs output window
[14:49:41 CET] <BlackFox> most helpful stuff like "?????????? g_hMutex != NULL ??????????"
[16:27:34 CET] <markvandenborre> hey! I'm using the -f tee command; I can succcessfully use -y -f tee "/tmp/foo.ts|/tmp/bar.ts"
[16:27:48 CET] <markvandenborre> but I want the second part of the tee to be thrown at an rtmp server
[16:27:57 CET] <markvandenborre> and that always seems to fail for some reason
[16:29:34 CET] <Pignoufou> Hi everyone! :)
[16:29:48 CET] <markvandenborre> Pignoufou: good morning
[16:30:57 CET] <Pignoufou> I've got a question regarding programmatic use of ffmpeg& basically I want to use ffmpeg to extract images from a video at specific time codes& I know how to extract one image from the CLI (or several at a specified interval) but what I'd like to do now is be able to extract images at several points, not necessarily time based
[16:31:54 CET] <Pignoufou> Also, what would be great would be to be able to keep the ffmpeg process open until I'm done (because I won't know the whole set of images at the beginning and I'd like to avoid wasting time with ffmpeg starting for every frame)
[16:32:06 CET] <Pignoufou> So question is& is there a way to do that?
[16:32:22 CET] <FishPencil> How is it that two playlists from the same bluray were encoded to very different sizes (1.6GB vs 3.1GB). The same x264 settings were used (CRF 25)
[16:34:15 CET] <Mysoft> Pignoufou i think on linux you can use a mkfifo
[16:34:21 CET] <Mysoft> and tell ffempg to read the fifo for the input
[16:34:39 CET] <Mysoft> and so every "image" you can send as input trough that fifo
[16:35:10 CET] <Mysoft> but ofcourse ffmpeg wont help you selectively choosing the frames from a different video
[16:35:54 CET] <Pignoufou> That's the thing I want to use ffmpeg to extract images. Otherwise I'll just implement it restarting a process every time or something like that until I can find a better solution :)
[16:36:17 CET] <Pignoufou> (I'm already using ffmpeg to encode from images I pass it through stdin)
[16:37:09 CET] <Mysoft> you could probabily make it output images in blocks of some seconds
[16:37:30 CET] <Mysoft> which then you can select which to fifo in on the second ffmpeg
[16:37:45 CET] <Pignoufou> Yes that's an alternative I'm thinking about :)
[17:11:01 CET] <neonfuz> Hey
[17:11:06 CET] <neonfuz> is there a long version of the option -an?
[17:13:35 CET] <techtopia> i don't think so
[17:14:24 CET] <Mysoft> hu why you would want that?
[17:38:30 CET] <neonfuz> trying to get retroarch to output to v4l2loopback
[17:38:45 CET] <neonfuz> retroarch talks to ffmpeg through the c api, and I want to disable audio
[20:20:39 CET] <Threads> i see ffmpeg loves greek women :D
[21:37:07 CET] <diffuse> I've been messing around with the ffmpeg C API and looking at the filter and muxer examples.  I was wondering if there was a decent examplt that would allow me to use the "segment" muxer.
[21:37:56 CET] <diffuse> I'd like to make a small C program to take a large video file and split it into a bunch of smaller segments (I see the ffmpeg command line tool does this, but I can't seem to locate the actual code)
[22:15:52 CET] <jason__> just use ffmpeg or call it from your program
[23:08:16 CET] <DHE> diffuse: most likely you need:  avformat_alloc_output_context2(avctx, NULL, "segment", "listfilename.m3u8");  and then you can specify a dictionary with your options in avformat_write_header
[23:08:32 CET] <DHE> this is from a reading of the docs and not actual experience. not tried the segment muxer from the API
[23:21:08 CET] <jarlath> I've found an example on stackoverflow that just copies the video but changes the audio format. I also want to just copy (passthru) the video but want to add a wav file as the audio track. How would I modify this to do that? ffmpeg -i input.avi -acodec mp3 -vcodec copy out.avi
[23:32:28 CET] <DHE> ffmpeg -i videofile.mp4 -i input.wav -c:v copy -c:a [codec-for-audio] output.mp4
[23:34:38 CET] <jarlath> DHE: thank you :)
[00:00:00 CET] --- Sun Nov 27 2016