[Ffmpeg-devel-irc] ffmpeg.log.20171023

burek burek021 at gmail.com
Tue Oct 24 03:05:01 EEST 2017


[00:04:52 CEST] <thebombzen> macroblocks
[00:11:27 CEST] <MilanDierick> Got a quick question: is it just me or is the link to download windows build packages offline?
[00:16:28 CEST] <SonicTheHedgehog> MilanDierick: I just downloaded the nightly git build, 64-bit, static from here https://ffmpeg.zeranoe.com/builds/
[00:16:33 CEST] <SonicTheHedgehog> MilanDierick: Seems to download fine.
[00:17:16 CEST] <MilanDierick> Oh, now I can acces the site properly again. Seems like the problem was on my side...
[00:17:52 CEST] Action: SonicTheHedgehog nods.
[00:31:02 CEST] <arpu> when i read  a rawvideo from a pipe can   and set the frame rate with -15 and -vsync cfr  the frame rate is not constant 15fps
[00:31:38 CEST] <arpu> how can i get a costant 15fps input ?  (dublicate or drop frames to get the 15fps)
[00:35:40 CEST] <marcurling> Hello, while trying to use -ilme (no video codec specified but h264/AVC ok for me) I get "Unrecognized option 'ilme'.
[00:35:40 CEST] <marcurling> Error splitting the argument list: Option not found"
[00:36:20 CEST] <JEEB> what are you trying to do? enable interlacism?
[00:36:31 CEST] <marcurling> (I'm willing to encode interlaced MPEG2 to interlaced AVC)
[00:36:38 CEST] <marcurling> yup
[00:36:57 CEST] <JEEB> the docs say MPEG-2 and MPEG-4 only
[00:37:32 CEST] <marcurling> so output.mp4 should work?
[00:37:49 CEST] <JEEB> uhh, that's the container
[00:38:48 CEST] <marcurling> What should be the -vcodec , please?
[00:39:11 CEST] <JEEB> I mean, that option doesn't work for any other encoders than such that you don't want to use
[00:39:20 CEST] <JEEB> since you want to use H.264/AVC (and thus most likely libx264)
[00:39:38 CEST] <JEEB> just checking if there's a way to enable but not force field order
[00:39:44 CEST] <JEEB> so it might get used from the input :P
[00:46:17 CEST] <maicod> hi can I use ffmpeg or ffprobe to run through an entire mp4 file to determine the peak bitrate used ?
[00:48:31 CEST] <JEEB> maicod: with -of json and -show_packets you can get some sort per-packet byte size, which you can then take together with the DTS/PTS and calculate some peaks, although I am not 100% that'd get you correct. for proper VBV/HRD you'd need to actually make sure that those things are the NAL units' sizes etc
[00:48:52 CEST] <JEEB> basically "peak bit rate" sounds like a simple thing, but what does one actually mean with it is the most important thing
[00:49:28 CEST] <JEEB> is it just maximum bits over a single sample used or over something else like VBV/HRD
[00:53:02 CEST] <maicod> thanks jeeb I'm not at all good with ffmpeg so your information dazzles me. I'm testing out a wifi connection and during a high action scene in a movie file I'm getting breaks in the playing while my wifi connection is 100 percent (wifi N at 1 meter distance from wifi router) and when trying copying files it usually does not go under the 3000 Kilobyte per second speed
[00:53:19 CEST] <maicod> so I was wondering what is the highest bitrate in that action scene
[00:56:18 CEST] <maicod> mediainfo gives 4500 Kbps as average which needs to be divided by 8 to get KBps so thats around 550 KBps only
[01:01:19 CEST] <marcurling> JEEB Did I get something wrong or should I wait from some more info from you?
[01:01:41 CEST] <marcurling> or may be it's no use encoding interlaced?
[01:02:14 CEST] <JEEB> x4->params.b_interlaced = avctx->flags & AV_CODEC_FLAG_INTERLACED_DCT;
[01:02:33 CEST] <JEEB> marcurling: well *you* should know if it's any use encoding interlaced
[01:02:38 CEST] <JEEB> since you requested it
[01:02:47 CEST] <JEEB> now to see if anything sets that flag
[01:03:03 CEST] <JEEB> marcurling: -flags ildct
[01:03:07 CEST] <JEEB> try that out with libx264
[01:03:16 CEST] <JEEB> if you really need interlacism
[01:03:44 CEST] <marcurling> For sure, encoding an interlaced source 'inretlaced' preserves quality
[01:04:03 CEST] <marcurling> ^trying out, thank you
[01:04:23 CEST] <JEEB> yea, if you don't want to deinterlace then of course for interlaced content that makes sense
[01:05:31 CEST] <JEEB> marcurling: libx264 should be dumping its internal parameters into the log as a long string at some point so you can keep your eye out for anything interlacism-related
[01:08:14 CEST] <inter123> Is someone of the ffmpeg users around here? I really need some help, would really appreciate it...
[01:09:10 CEST] <marcurling> inter123 on IRC just ask: Don't ask if you can ask
[01:10:43 CEST] <inter123> I am trying to download through a link, while it works on my windows version, it doesn't work on my linux static version(ubuntu 16.04): here's a screenshot:
[01:11:16 CEST] <inter123> https://i.imgur.com/6Zveobh.png
[01:12:15 CEST] <inter123> So, I get the "HTTP error 403 Forbidden", whereas it works perfectly fine in my windows version
[01:12:42 CEST] <inter123> Btw, I get the link from a kodi application(NBA League Pass)
[01:19:49 CEST] <marcurling> inter123 Can you give your whole command line? I'll give it a try on my Mint with recent ffmpeg
[01:20:52 CEST] <inter123> this is the whole command:
[01:20:53 CEST] <inter123> ffmpeg -i "https://nlds291.cdnllnwnl.neulion.com/nlds/nba/okc/as/live/nlncp/okc_hd_6000_ipad3.m3u8?h=3006515b18cab0586b26db8d0ff994f3.1508712951317&hdnea=exp=1508713011~acl=/*~hmac=18F0945DC2D17FF9504BB6FDA68E24E4002BCC743A70E20CA64CAF1733C781AE&nltid=nba&nltdt=6&uid=7799443|User-Agent=iTunes-AppleTV/4.1&Cookie=nlqptid%3Dh%3D3006515b18cab0586b26db8d0ff994f3.1508712951317%26hdnea%3Dexp%3D1508713011%7Eacl%3D/%2A%7Ehmac%3D18F0945DC2D17
[01:21:13 CEST] <inter123> but that link is already dead, so I will provide a new link:
[01:22:11 CEST] <inter123> here's the command with a working link now:
[01:23:23 CEST] <inter123> Actually, the link is too long to fit into the message, here's a pastebin link: https://pastebin.com/BH5vUtiP
[01:32:45 CEST] <marcurling> got the same error with ffmpeg 3.2.3, installing 3.4 and trying but I'm not shure it comes from ffmpeg itself
[01:35:51 CEST] <inter123> the links are only active for 1 minute tops, so I am afraid you tried too late already
[01:37:42 CEST] <inter123> as you can see, it works on my windows version:
[01:37:42 CEST] <inter123> https://i.imgur.com/qxZHpHq.png
[01:38:44 CEST] <inter123> Here's the whole command, plus the message from ffmpeg(in my windows version):
[01:38:45 CEST] <inter123> https://i.imgur.com/7HP6FqO.png
[01:38:56 CEST] <inter123> https://i.imgur.com/kBbfksk.png
[01:41:57 CEST] <marcurling> I was able to download a .ts file using the hhtps link but even mediainfo does not recognize it as a video file.
[01:42:52 CEST] <marcurling> But what we should do is check the compile options of the Win and linux version
[01:43:37 CEST] <inter123> How do I check the Win compile options?
[01:44:03 CEST] <marcurling> just 'ffmpeg' in the command line
[01:44:48 CEST] <inter123> win: https://i.imgur.com/ylTqhqw.png
[01:45:17 CEST] <inter123> and about linux, I have this static build: https://www.johnvansickle.com/ffmpeg/
[01:47:22 CEST] <inter123> here's a screenshot for linux also: https://i.imgur.com/eyMOczz.png
[01:47:37 CEST] <marcurling> make both outputs a text file (ffmpeg 2> ffmpeglinux.txt under linux) and compare with diff or any nice text editor (notepad++ can do it uner win)
[01:48:01 CEST] <marcurling> Sorry but got to leave you: it is way late here
[02:26:34 CEST] <jiffe> so I've ripped all my tv shows to disk, I'm looking for an automated way to find the intros and credits
[02:27:29 CEST] <jiffe> I'm thinking something that will find sections of videos of N+ seconds which are exactly the same between them all
[02:27:40 CEST] <jiffe> I don't know if something like that exists
[02:30:26 CEST] <jiffe> I don't know if you can just create a hash of the last X frames to compare them or if the encoded content would still be slightly different
[02:31:06 CEST] <DHE> not that easy. it would need to be a hash that can cope with encoding variants. the video won't be pixel identical each time
[02:31:28 CEST] <DHE> you might do better with black detection and timing to identify the black screen between transitions
[02:32:35 CEST] <jiffe> hmm I see
[10:12:08 CEST] <rabbe> hey.. just got a better WHDL transmitter/receiver.. now my ffmpeg command which creates an rtmp for nginx produces too large speed, so that when i receive the (flv over) rtmp i get slow motion. what to do? should i paste the command here?
[10:13:06 CEST] <teratorn> rabbe: it wont hurt
[10:13:24 CEST] <rabbe> just a second.. it's on another puter
[10:14:25 CEST] <JEEB> usually the thing is to paste the command and logging with your RTMP credentials hidden onto a pastebin-like site
[10:14:28 CEST] <JEEB> and then link here
[10:14:33 CEST] <JEEB> but uhh
[10:14:38 CEST] <JEEB> so you have a faster-than-realtime input?
[10:15:31 CEST] <rabbe> ffmpeg -r 30 -f v4l2 -video_size hd1080 -i /dev/video0 -c:a aac -ac 2 -b:a 128k -c:v libx264 -pix_fmt yuv420p -preset ultrafast -tune zerolatency -x264-params "nal-hrd=cbr" -b:v 3000k -minrate 3000k -maxrate 3000k -bufsize 3000k -g 60 -f flv rtmp://192.168.0.16/live/test
[10:15:46 CEST] <rabbe> probably a crappy command :)
[10:16:07 CEST] <rabbe> ah, sorry.. well, already pasted
[10:16:18 CEST] <JEEB> well at least that isn't too long
[10:16:37 CEST] <JEEB> and if that's supposed to be live then I can't see how it's going too fast
[10:16:42 CEST] <JEEB> since that seems like live input
[10:17:52 CEST] <rabbe> ffplay -fflags nobuffer gives me slow motion..
[10:18:20 CEST] <JEEB> are you sure your encoder is going fast enough :P
[10:18:44 CEST] <JEEB> or many other things, also no idea what ffplay can f' up
[10:19:14 CEST] <rabbe> now i get the stream from gorpro hero5 into capture card magewell HDMI->USB3
[10:19:29 CEST] <JEEB> for RTMP reference flash is unfortunately the reference :P
[10:19:43 CEST] <rabbe> this worked fine with the cheaper WHDL transmitter/receiver
[10:20:04 CEST] <furq> when you say "slow motion" do you mean like exactly half speed
[10:20:05 CEST] <JEEB> anyways, just read the log and try with -v verbose f.ex.
[10:20:19 CEST] <furq> or just choppy or something
[10:20:25 CEST] <rabbe> in ffmpeg side or ffplay side?
[10:20:31 CEST] <JEEB> ffmpeg
[10:20:46 CEST] <JEEB> and start capturing the log with 2> ffmpeg_log.txt or so
[10:21:05 CEST] <furq> also does it play back correctly if you write to a file
[10:21:13 CEST] <JEEB> yea
[10:21:28 CEST] <JEEB> you can just write FLV locally and try playing that
[10:21:37 CEST] <rabbe> will check
[10:21:39 CEST] <JEEB> with mpv for example (although that does use the same lavf library)
[10:21:49 CEST] <furq> if it is exactly half speed then maybe the camera isn't playing nice with v4l and sending 60fps
[10:21:53 CEST] <JEEB> if you want a "reference" play then you have to grab a flash-based player :P
[10:22:02 CEST] <furq> that's my only guess based on that command
[10:22:10 CEST] <JEEB> could be
[10:22:21 CEST] <JEEB> although slow speed should desync
[10:23:06 CEST] <furq> yeah i'm not going to say it's a good guess
[10:23:53 CEST] <rabbe> ah, setting -r 60 instead gives me speed 1
[10:24:08 CEST] <furq> nice
[10:24:44 CEST] <furq> maybe it was a good guess after all
[10:25:11 CEST] <rabbe> i wonder if setting -r higher than 60 will show me the future :)
[10:25:23 CEST] <rabbe> thanx
[10:25:35 CEST] <furq> you can set -r 30 after -i if you want to drop alternate frames
[10:26:01 CEST] <rabbe> alternate frames?
[10:26:28 CEST] <furq> if you want a 30fps output from a 60fps input
[10:26:35 CEST] <furq> which you probably do at that bitrate
[10:26:36 CEST] <rabbe> ah, okay
[10:27:10 CEST] <rabbe> but i keep the -r 60 to get the stream input ok
[10:27:17 CEST] <furq> yeah
[10:27:32 CEST] <furq> -framerate 60 or -r 60 before -i, -r 30 after
[10:28:18 CEST] <rabbe> yeah, because we had robot functionality running on the same computer which lagged so we figured ffmpeg was hogging too much CPU
[10:28:32 CEST] <rabbe> we had 5000 instead of 3000
[10:28:56 CEST] <rabbe> does it make sense to change all of those 5000 to 3000?
[10:29:26 CEST] <rabbe> bufsize + all bitrate parameters
[10:30:03 CEST] <furq> depends how much bandwidth you've got really
[10:30:10 CEST] <furq> with those settings you probably want it as high as you can get away with
[10:31:51 CEST] <rabbe> i'm planning on using uv4l instead so i won't need to specify this.. but what kinda settings would give me better quality?
[10:32:12 CEST] <rabbe> at the same bandwidth?
[10:33:21 CEST] <furq> if you actually need preset ultrafast and tune zerolatency then there's not really much you can do
[10:33:32 CEST] <furq> those two disable pretty much everything good
[10:34:16 CEST] <rabbe> ah, okay..
[10:34:37 CEST] <furq> i'm not sure if you actually need ultrafast to reduce latency, so maybe try stepping that up if you have the cpu time
[10:34:52 CEST] <rabbe> does these settings specify a specific h264 baseline also?
[10:35:02 CEST] <rabbe> i mean, baseline main etc
[10:35:16 CEST] <rabbe> okay..
[10:35:21 CEST] <JEEB> those are profiles, x264 sets it according to your settings' features used
[10:35:22 CEST] <furq> not explicitly but i'm pretty sure that'll be baseline
[10:35:23 CEST] <JEEB> and other things
[10:35:49 CEST] <JEEB> profiles = features required from decoder, levels = amount of memory required from decoder
[10:36:05 CEST] <furq> i'm guessing you need zerolatency and fastdecode, in which case you've got no bframes or cabac
[10:36:12 CEST] <furq> so tuning anything else is probably a waste of time
[10:36:21 CEST] <furq> it's not something i've ever messed with though
[10:36:23 CEST] <JEEB> CABAC already would be a nice thing
[10:36:28 CEST] <furq> yeah
[10:36:40 CEST] <rabbe> -preset fastdecode?
[10:36:44 CEST] <furq> tune
[10:36:48 CEST] <furq> you can have multiple tunes
[10:36:52 CEST] <JEEB> well it's pretty much already set :P
[10:36:53 CEST] <rabbe> ah
[10:36:55 CEST] <JEEB> because of ultrafast
[10:36:59 CEST] <furq> yeah
[10:37:00 CEST] <JEEB> CABAC is not used etc
[10:37:11 CEST] <JEEB> do you really need ultrafast?
[10:37:18 CEST] <JEEB> that really cripples compression
[10:37:21 CEST] <rabbe> not sure
[10:37:23 CEST] <JEEB> it's really made for >200fps+
[10:37:27 CEST] <rabbe> oh
[10:37:30 CEST] <JEEB> on any relatively sane thing
[10:37:47 CEST] <furq> i'm not sure if fastdecode actually helps with latency
[10:37:49 CEST] <rabbe> no, i think the quality is a bit bad
[10:37:49 CEST] <JEEB> of course it depends how powerless your thing is, and if you've found a binary that's somehow compiled without hand-writtem SIMD enabled
[10:37:53 CEST] <JEEB> furq: it doesn't
[10:37:55 CEST] <furq> or if it's just there for toasters
[10:38:00 CEST] <JEEB> it's just for toasters
[10:38:10 CEST] <JEEB> zerolatency does the things that help latency (disables lookaheads, b-frames etc)
[10:38:27 CEST] <JEEB> ultrafast is for "I need faster and don't care about anything else"
[10:38:36 CEST] <furq> good to know
[10:38:42 CEST] <Archer> hey
[10:38:54 CEST] <furq> well yeah if the encoding box can deal with cabac then you definitely want that on
[10:38:59 CEST] <furq> try -preset superfast
[10:39:41 CEST] <rabbe> ok
[10:39:55 CEST] <Guest51818> I wanted to see if there was a way to search video for a specific color using ffmpeg. I'm trying to get the times of kills in multiple hours of PUBG footage and it always displays reddish-orange text whenever there is a kill
[10:40:17 CEST] <Guest51818> I'd like to not manually go through the videos
[10:42:08 CEST] <hendry> given a m3u8 URL, is there a tool to download the manifest and the referenced .ts? I feel youtube-dl should do it, but it seems to assemble all the segments, which I don't want.
[10:42:55 CEST] <furq> Guest51818: there's no simple way
[10:43:01 CEST] <furq> maybe you could do it with crop and signalstats
[10:44:11 CEST] <furq> hendry: maybe youtube-dl --keep-fragments
[10:44:23 CEST] <furq> afaik that'll still assemble but it'll keep the fragments after it's done
[10:44:45 CEST] <furq> there's probably another option somewhere that'll prevent the final muxing
[10:46:03 CEST] <furq> failing that, grep and curl
[10:46:05 CEST] <furq> bye
[10:46:13 CEST] <Guest51818> huh okay gonna have to read up on that
[10:46:21 CEST] <furq> !filter signalstats @Guest51818
[10:46:21 CEST] <nfobot> Guest51818: http://ffmpeg.org/ffmpeg-filters.html#signalstats-1
[10:46:24 CEST] <Guest51818> spin up a linux VM too
[10:47:09 CEST] <Guest51818> probably run it across a kill clip and see how the numbers differ from normal non-kill footage
[10:47:20 CEST] <furq> basically crop to the area where the hud message appears, run signalstats and look for frames with HUEAVG in a certain range
[10:47:41 CEST] <furq> you should be able to script that once you know what to look for
[10:48:07 CEST] <Guest51818> thanks man you just saved me hours of document reading, easy
[10:53:13 CEST] <Guest51818> hah there is a Windows x64 build, hurrah for not having to go to a linux VM
[12:02:24 CEST] <Guest51818> okay ive got the ffplay command with the crop on the kill essage
[12:02:29 CEST] <Guest51818> *message
[12:39:58 CEST] <Guest51818> hey furq you were bang on, HUEAVG is spiking at 250 on killmsg in cropped area
[12:41:05 CEST] <Guest51818> can probably get something up with gnuplot
[12:41:10 CEST] <Guest51818> or Excel
[20:23:05 CEST] <lagzilla> is it possible to pipe a merged audio stream? ffmpeg -i input1.wav -i input2.wav -filter_complex "[0:a][1:a]amerge=inputs=2,pan=stereo|c0<c0+c1|c1<c2+c3[aout]" -map "[aout]" - | ffplay
[20:23:09 CEST] <lagzilla> isn't working for me
[20:28:09 CEST] <ChocolateArmpits> lagzilla, well there's no format specified
[20:28:34 CEST] <ChocolateArmpits> and I think ffplay needs a "-" for pipe input too
[20:32:38 CEST] <lagzilla> how would I set the format? I can't find any example
[20:32:48 CEST] Action: lagzilla sucks at google
[20:34:33 CEST] <relaxed> lagzilla: -f wav
[20:34:41 CEST] <DHE> you choose based on the content type, but it should be something that can be streamed
[20:34:58 CEST] <DHE> being audio, yeah wav is probably a good start
[20:35:09 CEST] <lagzilla> thanks!
[23:40:25 CEST] <durka42> Hi, I have a question about -progress. The man page says "-progress url (global)      Send program-friendly progress information to url." But what's a URL in this context? Can I have it use a named pipe or unix socket etc, with some syntax?
[23:44:52 CEST] <c_14> yep
[23:45:12 CEST] <c_14> any file or url that ffmpeg knows how to open and write to
[23:45:33 CEST] <durka42> ok, so just mkfifo and give the filename
[23:46:49 CEST] <c_14> ye
[00:00:00 CEST] --- Tue Oct 24 2017


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