[Ffmpeg-devel-irc] ffmpeg.log.20180525

[burek]

[01:33:48 CEST] <johnnny22> Hi guys & girls
[01:35:14 CEST] <johnnny22> I'm having problems encoding this short part of a stream that can be found at http://frederic.bochmann.ca/hevc/source/sample_fmp4_fmp4/master.m3u8
[01:35:32 CEST] <johnnny22> I get something like " could not find corresponding track id 0 "
[01:35:50 CEST] <johnnny22> and it quickly dies with "Too many packets buffered for output stream 0:1."
[01:39:10 CEST] <johnnny22> trying to figure out either whats wrong with the stream or ffmpeg ;)
[01:40:48 CEST] <JEEB> http://up-cat.net/p/00b68a8a
[01:41:56 CEST] <JEEB> ah, fun there's multiple messages like that in mov.c
[01:42:08 CEST] <johnnny22> 2 of them :)
[01:42:13 CEST] <johnnny22> if i recall right
[01:43:14 CEST] <JEEB> tfdt, trun, sidx
[01:43:25 CEST] <johnnny22> JEEB: not sure if you'll need libx265 as it's hevc in the video
[01:43:29 CEST] <JEEB> no
[01:43:32 CEST] <JEEB> the decoder is internal
[01:43:38 CEST] <johnnny22> ah right, ok
[01:43:39 CEST] <JEEB> 99% of all decoders are internal
[01:44:30 CEST] <JEEB> this is 100% container thing, it seems to refer to track IDs that are not there in things (most likely because it opens up new demuxers for fragments? not sure)
[01:46:16 CEST] <JEEB> with stream copy I did get both video and audio, though
[01:46:20 CEST] <JEEB> so it isn't fatal?
[01:46:37 CEST] <JEEB> `ffmpeg -v verbose -i "http://frederic.bochmann.ca/hevc/source/sample_fmp4_fmp4/master.m3u8" -c copy -movflags faststart out.mp4`
[01:46:50 CEST] <JEEB> this actually finishes
[01:47:16 CEST] <JEEB> of course it seems like something wonky happens in timestamps
[01:47:40 CEST] <johnnny22> but the out.mp4 doesn't show the video anymore
[01:47:52 CEST] <JEEB> worked for me
[01:48:13 CEST] <johnnny22> i'll try another player (was using vlc)
[01:48:25 CEST] <JEEB> I get a cathedral and some audio in mpv
[01:48:35 CEST] <johnnny22> oh works
[01:48:45 CEST] <johnnny22> right, and then a change of scene
[01:48:56 CEST] <johnnny22> and then another
[01:49:03 CEST] <JEEB> the timestamp messages are kind of worrying during the remux, but I'm not gonna debug this at 3am :D
[01:49:10 CEST] <JEEB> I've already herped a derp enough for the past 24h
[01:49:20 CEST] <johnnny22> haha
[01:49:33 CEST] <johnnny22> Is there a way to clone that behavior with you know what other player ? :)
[01:49:48 CEST] <JEEB> I'll have to check wtf is going on first
[01:49:58 CEST] <JEEB> not now, now I sleep and wake up in 5h and go to work
[01:50:04 CEST] <johnnny22> aight :D
[01:50:12 CEST] <johnnny22> thanks for the eyes on this though ! :)
[01:50:39 CEST] <johnnny22> I'll keep on digging around and will keep you posted if i find out more.
[01:50:59 CEST] <johnnny22> I'll try to create a source that has timestamps that start at 0 , instead of system time based :P
[01:53:56 CEST] <johnnny22> JEEB: 0 based seems to work better for now :P
[01:54:19 CEST] <johnnny22> JEEB: 0 based seems to work better for now :P but as soon as the window has slided away it's kaput
[01:55:00 CEST] <johnnny22> I mean, if the window has slided, starting ffmpeg on an already slided playlist seems to make it fil.
[01:55:04 CEST] <johnnny22> fail ^
[07:12:07 CEST] <fa0> Hello
[07:13:10 CEST] <fa0> Some older rips I've been going through and removing Title Tags that were previously set, I thought '-map_metadata -1' will only remove metadata tags? But it's also removing a second audio stream...
[07:13:29 CEST] <fa0> I have these;
[07:13:30 CEST] <fa0>  Stream #0:1(eng): Audio: aac (LC), 48000 Hz, stereo, fltp (default)
[07:13:39 CEST] <fa0>  Stream #0:2(eng): Audio: aac (LC), 24000 Hz, mono, flt
[07:13:52 CEST] <fa0> And that last mono stream gets removed with -map_metadata -1
[07:14:14 CEST] <fa0> This is in Linux with ffmpeg-3.4.2
[07:14:30 CEST] <fa0> This is the cmd I'm running from a script;
[07:14:32 CEST] <fa0> urxvt -g 120x32 -e ffmpeg -i "$i" -c:v copy -sn -map_metadata -1 -c:a copy "$OUTPUT/${i%.*}.mkv"
[07:16:05 CEST] <fa0> To remove only a Title tag, should I only use this instead? -metadata title=
[07:18:36 CEST] <fa0> SORRY my bad, I realize now -c:a copy isn't copying all the audio streams... :(
[07:18:40 CEST] Action: fa0 bangs head
[07:19:24 CEST] <furq> fa0: -map 0
[07:19:32 CEST] <fa0> yeah I just saw that LOL
[07:19:37 CEST] <fa0> oh boy, I be dummy...
[07:20:00 CEST] <furq> honestly the default stream mapping behaviour is kind of dumb
[07:20:09 CEST] <furq> it's just one of those legacy things i guess
[07:20:43 CEST] <fa0> hmm
[07:21:01 CEST] <fa0> yeah I thought by now -c:a copy would do it all...
[07:26:45 CEST] <fa0> furq: if I just want the first two streams then use this? --> -map 0:1 -map 0:2
[07:43:49 CEST] <furq> you presumably want -map 0:v as well
[07:44:15 CEST] <fa0> yeah that's 0:0
[07:44:32 CEST] <fa0> So I'm doing it like this now;
[07:44:33 CEST] <fa0> urxvt -g 120x32 -e ffmpeg -i "$i" -map 0:0 -map 0:1 -map 0:2 -c:v copy -sn -map_metadata -1 -c:a copy "$OUTPUT/${i%.*}.mkv"
[07:50:36 CEST] <fa0> To be honest I didn't originally rip these, not sure why it has 2 audio tracks for the video, stereo and mono... I personally don't get or see the benefit here...
[07:50:37 CEST] <fa0> hmm
[08:04:51 CEST] <fa0> furq: thanks for help
[08:55:28 CEST] <alex108> is there a way to not drop frames when resampling PAL 25 fps to film 24 fps. setpts=N/(24*TB) keeps dropping frames
[08:57:05 CEST] <faxmodem> you could slow down frame rate, I guess
[08:57:53 CEST] <mifritscher> moin
[09:00:17 CEST] <mifritscher> is there a documentation what max_buffer and rtbufsize do exactly (in case of rtsp)? For example: Does max_buffer set more a "default buffer" (aka delay), and does rtbufsize causes always delay or only if data comes too fast (what case would that be?)
[09:03:01 CEST] <alex108> slow down frame rate in what way? -r 25 in and -r 24 out will decimate, so will the fps=24 filter. also tried setpts=N/(24*TB),fps=24, way less drops within the two digits
[09:07:29 CEST] <mifritscher> alex108: My input is a rtsp webcam connected via wireless
[09:08:31 CEST] <mifritscher> the output straight from the camera is smooth, but the wlan causes 300 ms pauses every few seconds, which can be seen in the output of ffmpeg as well (I'm using the library directly)
[09:09:20 CEST] <mifritscher> so I would like to have a 500ms long buffer
[09:10:24 CEST] <alex108> mifritscher, I was actually asking too, my bad
[09:10:44 CEST] <mifritscher> no problem :-)
[10:01:26 CEST] <Ivan_> Hello
[10:04:47 CEST] <Nacht> Anyone have experiance using WEBDAV with authentication with FFMPEG ? I can't seem to figure out where to specify the user/pass
[10:09:00 CEST] <BtbN> https://user:password@blabla.de/.... I guess
[10:55:08 CEST] <mohamed_> hello everyone
[10:55:41 CEST] <mohamed_> i have a little question
[10:56:00 CEST] <mohamed_> I'm trying to create video from images
[10:56:21 CEST] <mohamed_> I use this command line :
[10:56:31 CEST] <mohamed_> ffmpeg -i out*.png videoout.avi
[10:58:53 CEST] <ubitux> http://ffmpeg.org/ffmpeg-formats.html#toc-image2-1 + http://ffmpeg.org/ffmpeg-formats.html#Examples-1
[11:43:05 CEST] <Ivan_M> hello. Maby anybody know howto fix this trouble - Timestamps are unset in a packet for stream 0. This is deprecated and will stop working in the future. Fix your code to set the timestamps properly
[11:43:23 CEST] <Ivan_M> i probe cut some part of file
[14:00:07 CEST] <Hackerpcs> why on show_entries mode the frame rate of a 23,976 fps, avg_frame_rate is 13978/583 ?
[14:00:44 CEST] <Hackerpcs> on ffprobe
[14:04:04 CEST] <Hackerpcs> i mean why it isn't pretty like the 23,976 :P
[14:04:16 CEST] <Hackerpcs> i used the -pretty option
[14:36:13 CEST] <xwni> Hi Folks,   can anyone help me build a filter_complex command;     I've got it adding an overlay image to a video;  and writing out the result...       I want to change it to append a fullscreen jpg to the end, say to display the jpg for 5 seconds at the end of the video.
[14:50:40 CEST] <kubast2> Anyone knows whether veryslow/placebo first pass improve quality over ultrafast/superfast/veryfast first pass?
[14:53:24 CEST] <BtbN> the preset for first and second pass have to match, otherwise the recorded data is useless
[14:53:35 CEST] <BtbN> also, placebo is named placebo for a reason.
[14:57:12 CEST] <xwni> https://pastebin.com/06SNt4J6  ; I have added a png overlay onto a mp4.   Can anyone help me with a command to append an image at the end of the result -  to display for 5 seconds (with 5 secs silence).
[14:58:38 CEST] <alex108> I gave up on resampling with setpts, loading an avisynth script and remuxing audio with atempo worked out
[15:30:01 CEST] <Diag> sorry if my znc spammed
[16:20:29 CEST] <aiena> I have a series of m4s segments. For video and audio. I just downloaded all the video segments and concatenated them together. If I do ffmpeg -i foo.mps bar.mp4 it works for the video. How do I convert the video and audio m4s data to an mp4?
[16:20:57 CEST] <aiena> *ffmpeg -i foo.m4s bar.mp4
[16:21:30 CEST] <aiena> her foo.4s is the concatenated segments data. from segment-0.m4s to segment-n.m4s
[16:21:35 CEST] <aiena> *m4
[16:21:38 CEST] <aiena> *m4s
[17:18:19 CEST] <anill> Hello people, suppose i make a skype video call from one user to another how can i give the live stream to ffmpeg to capture the traffic of the call and generate a final H264 video file.
[17:27:59 CEST] <ChocolateArmpits> anill, it'd probably make more sense to use a screengrabber
[17:29:08 CEST] <anill> ChocolateArmpits: Hi do you know how can i give live streams to ffmpeg and make it output an MP4/H264 file
[17:31:48 CEST] <ChocolateArmpits> anill, it's just simple ffmpeg -i [streamlink] output.mp4
[17:32:09 CEST] <ChocolateArmpits> additionally specify bitrate with -b:v [size]
[17:32:37 CEST] <anill> ChocolateArmpits: Thanks :)
[17:32:56 CEST] <ChocolateArmpits> without the brackets of course
[17:56:07 CEST] <johnnny22> JEEB: So, after further testing -c:a copy seems to help, but AV sync seems to get ~0.2s late audio. It seems to play in sync with other engines like vlc and web-players.
[17:57:10 CEST] <JEEB> it can be a whole lot of things, I'd have to check it after I have the time. if you can provide a description with ffmpeg.c to trac.ffmpeg.org (tested with as new FFmpeg as possible, since you most likely will be asked to do that anyways)
[17:58:36 CEST] <johnnny22> right, are the windows nightly builds found at https://ffmpeg.zeranoe.com/builds/ good enough ? :)
[18:00:15 CEST] <JEEB> should be
[18:00:26 CEST] <JEEB> ffmpeg -version should give the -gXXXXX git revision
[18:00:59 CEST] <johnnny22> *thumbs up*
[18:01:14 CEST] <johnnny22> and what did you mean by "description with ffmpeg.c" ?
[18:04:01 CEST] <JEEB> as in, use cases with the FFmpeg command line tool, which is ffmpeg.c
[18:04:11 CEST] <johnnny22> aah okay ;)
[19:02:12 CEST] <saml_> how can I do content aware encoding?
[19:02:17 CEST] <saml_> --content-ware=1 ?
[19:02:43 CEST] <durandal_1707> wtf?
[19:02:59 CEST] <saml_> if a video is animation then becomes sports event, can ffmpeg dynamically change encoding params for optimal result?
[19:03:31 CEST] <durandal_1707> no
[19:04:00 CEST] <saml_> would it be useful to have such feature? or just a lot of work to implement such with little reward?
[19:04:24 CEST] <saml_> i guess codecs are already smart enough (adaptive enough)
[19:13:39 CEST] <furq> is there even such a thing as realtime context-aware encoding
[19:14:29 CEST] <saml_> you can build one for me so i can use it for free
[19:14:42 CEST] <furq> i'd be surprised if that's even possible to do well
[19:15:39 CEST] <tdr> realtime aware vs realtime capable, "aware" would me its doing scope creep outside its job to find out about scheduling etc.  ugly
[19:15:47 CEST] <saml_> deep learning + big data + ... =
[19:15:53 CEST] <furq> lol
[19:16:45 CEST] <furq> dynamic content media experience enables cloud disruption
[19:17:30 CEST] <saml_> but isn't there some kind of theoretical limit of bitrate? and we can calculate how much bandwidth cost it'll save
[19:18:17 CEST] <furq> iptv almost always uses cbr anyway
[19:18:43 CEST] <saml_> instead of trying to cut the cost, need to find ways to earn money more
[19:19:51 CEST] <furq> well yeah dynamically changing encoding params in the middle of a stream is possible and well supported
[19:19:54 CEST] <furq> it's just not possible in ffmpeg
[19:20:25 CEST] <furq> at least with x264 you need to reinit the encoder to change params
[19:21:30 CEST] <saml_> hrm i see
[19:21:39 CEST] <furq> so if you're able to analyse (or preferably encode) the different stream segments ahead of time, this isn't that complicated a problem
[19:21:53 CEST] <furq> but doing it in realtime sounds awful
[19:21:59 CEST] <saml_> would it be helpful to analyze video  and generate ffmpeg arguments per video file?
[19:22:17 CEST] <furq> unless you're encoding the segments ahead of time you shouldn't use the ffmpeg cli for this at all
[19:22:40 CEST] <saml_> yeah this will be something like youtube  (no live stream)
[19:22:52 CEST] <furq> the networking stuff in ffmpeg is more of a convenience than anything else
[19:23:04 CEST] <furq> i wouldn't do anything remotely critical with it
[19:23:44 CEST] <saml_> what do you mean?  instead of  ffmpeg -i http://...     -f mp4 http://...     save to file?
[19:24:02 CEST] <furq> i mean you can do that and it'll probably work
[19:24:16 CEST] <furq> but error handling for all network stuff is practically nonexistent
[19:24:18 CEST] <saml_> but it's better/safer to save to disk, right?
[19:24:24 CEST] <saml_> ah i see
[19:25:16 CEST] <furq> it sounds like you need to use the libs anyway
[19:25:38 CEST] <saml_> so i get 2 hour video. segment it first (delivery will be HLS). encode segments. upload encoded segments
[19:26:06 CEST] <furq> sure
[19:26:06 CEST] <saml_> different ffmpeg params maybe applied to each segment
[19:26:26 CEST] <saml_> let's build this
[19:26:50 CEST] <furq> i have no idea how well that'll handle SPS changing mid-stream
[19:27:02 CEST] <furq> i guess you'll find out soon enough
[19:27:14 CEST] <saml_> https://sps.cuny.edu/  ?  what is sps?
[19:27:25 CEST] <furq> sequence parameter set
[19:27:31 CEST] <furq> one of the h264 headers
[19:27:45 CEST] <saml_> okay let's not use different ffmpeg params per segment
[19:27:59 CEST] <furq> i'm not saying it won't work
[19:28:17 CEST] <saml_> it'll be future feature
[19:28:29 CEST] <furq> sending a new SPS mid-stream generally works fine in most players in mpegts
[19:28:42 CEST] <furq> idk how web players will handle it
[19:28:58 CEST] <saml_> what output format would you choose for segmenting? mp4 with -crf 0?
[19:29:00 CEST] <furq> also yeah this sounds like something the ffmpeg cli will handle just fine
[19:29:11 CEST] <furq> i would use mpegts
[19:29:25 CEST] <saml_> segmenting first enables me to parallelize encoding
[19:29:31 CEST] <furq> oh
[19:29:39 CEST] <furq> i take it you mean across multiple machines
[19:29:46 CEST] <saml_> yeah
[19:30:02 CEST] <saml_> ffmpeg already maximizes all cores
[19:30:46 CEST] <saml_> if i can segment 2 hour videos and massively parallelise it and encode everything with 200 machines...
[19:32:04 CEST] <furq> that sort of seems like it's only worth doing if you have hundreds of videos
[19:32:40 CEST] <saml_> yeah thousands a day or more
[19:32:59 CEST] <furq> oh right you're making a youtube clone
[19:33:00 CEST] <furq> nvm then
[19:33:18 CEST] <saml_> there are so many video companies: youtube, vimeo, dailymotion,...  not sure why there's no tool i can just download and use
[19:35:20 CEST] <saml_> https://stackoverflow.com/questions/35133119/ffmpeg-splitting-large-files   there's already solution
[19:36:37 CEST] <furq> you probably want to double check the audio is correct after doing that
[19:37:02 CEST] <furq> cutting with -c copy and relying on ffmpeg to just find the nearest keyframe has a tendency to screw up the audio
[19:37:10 CEST] <furq> but hopefully the segment muxer is smart enough to not do that
[19:37:30 CEST] <furq> if it doesn't work you can always just remove the audio and encode that by itself
[19:37:32 CEST] <ChocolateArmpits> youtube does exactly that, it segments and encodes each segment separately, applying some additional quality correction
[19:37:47 CEST] <ChocolateArmpits> furq,  it would be smarter to separate video and audio
[19:37:55 CEST] <furq> that's what i said
[19:38:08 CEST] <ChocolateArmpits> missed
[19:38:19 CEST] <furq> maybe i didn't say it very clearly
[19:38:21 CEST] <furq> that's what i meant anyway
[19:38:30 CEST] <ChocolateArmpits> nah you did, I just skimmed
[19:39:10 CEST] <furq> but yeah it probably is a good idea in general to not segment the audio
[19:46:25 CEST] <saml_> ChocolateArmpits, do you  have youtube script?
[19:51:52 CEST] <saml_> if I separate audio, HLS segments won't have audio
[19:52:22 CEST] <saml_> I guess, separate audio, segment, encode, combine segments and audio back,  then segment again for HLS?
[00:00:00 CEST] --- Sat May 26 2018