[Ffmpeg-devel-irc] ffmpeg.log.20150212

burek burek021 at gmail.com
Fri Feb 13 02:05:01 CET 2015

[01:16] <mike_g> I have an offer for some freelance work: https://www.elance.com/j/ffmpeg-remux-application/68694902/
[01:16] <mike_g> Small demo app, going back the community.
[03:34] <k_sze[work]> I'm running into some weirdness with file.
[03:34] <k_sze[work]> The frame times are very weird, as you can see in this paste: https://bpaste.net/show/22e5bcc41436
[03:36] <k_sze[work]> This is actually the H.264 stream grabbed from a Logitech C920 webcam, piped to ffmpeg, and muxed into a .nut file using `-c:v copy -copyinkf` options.
[03:36] <k_sze[work]> The weird frame times make seeking rather hellish.
[03:41] <k_sze[work]> Is there a way to tell ffmpeg to strip frame time from the incoming stream and recalculate more normal frame times?
[03:42] <k_sze[work]> Because otherwise I doubt I can do frame accurate seeking.
[03:54] <c_14> You can try igndts or genpts
[04:15] <k_sze[work]> c_14: I just tried `-vsync drop`
[04:15] <k_sze[work]> seems to help
[04:15] <k_sze[work]> frame times look a lot more normal now, though there seems to be a gradual drop of precision as time increases.
[04:16] <k_sze[work]> I suspect it has to do with the limitations of float numbers.
[04:16] <k_sze[work]> Which I *should* be able to cope with.
[04:24] <k_sze[work]> Another weirdness is when I pipe raw video to ffmpeg and let it encode as H.264. ffmpeg would assign a time of 0.0666666666667 to the very first frame.
[04:24] <k_sze[work]> instead of just 0.0
[06:06] <johnvantes> Hi Everyone!
[06:06] <johnvantes> I have question, what is the fastest way to create a long video with an image? Here is what I have now:
[06:06] <johnvantes> ffmpeg -loop 1 -i image.jpg -c:v libx264 -preset ultrafast -t 3600 -pix_fmt yuv420p -vf scale=640:480 image.mp4
[06:07] <johnvantes> http://pastebin.com/EedxDxAc
[06:08] <johnvantes> It does the job well, but it's taking too long in my case, probably around 40minutes to an hour.
[06:08] <johnvantes> If anyone can suggest the fastest method I would really appreciate that !
[06:34] <relaxed> johnvantes: add -preset sillimage and lower the frame rate
[06:34] <relaxed> maybe -r 15 or so
[09:33] <tartinette> Hi
[09:54] <hta> Check for known error: I create an YUV file, encode with x265, decode with ffmpeg. The result is one frame shorter than what I started with. Is this a known bug, a setting that I don't know about, or something to report?
[09:56] <ribasushi> hta: can you try the same with x264 to zoom in to which part of the chain is problematic?
[09:57] <hta> ribashushi: I've done tons of these encodes with x264 with no issue. The x265 is the new part.
[09:59] <hta> x265 reports encoding 10 frames. resulting yuv file size matches a file with only 9 frimes.
[10:48] <hta> seems to be a bug in ffmpeg tip-of-tree. n2.5.3 works fine.
[10:52] <durandal_1707> hta: what bug?
[10:54] <hta> durandal: encoding a file with x265 and then decoding it with ffmpeg produces a file that is one frame smaller than the original file.
[10:55] <hta> I spoke too soon; n2.5.3 works fine with 10 frames, but not with a file of 501 frames.
[11:05] <hta> and just for fun, HM decodes the file to a THIRD size....
[11:28] <Ders> Can anyone help me with getting named pipes to work in windows with ffmpeg?
[11:46] <t4nk291> hi
[11:47] <t4nk291> I have a problem with ffmpeg using libx264 encoder
[11:47] <t4nk291> http://pastebin.com/dQjkCKQc
[11:47] <t4nk291> any help?
[11:48] <t4nk291> the command vncrec  does  -pixel_format rgb24 -video_size 640x480 -framerate 25
[11:49] <Ders> Hold on. I'll take a look
[11:50] <t4nk291> thanks. the example i got from here http://panthema.net/2014/vncrec-rgb/
[11:51] <Ders> This is your first error if you didn't notice this:
[11:51] <Ders> Invalid buffer size, packet size 201841 < expected frame_size 921600
[11:53] <Ders> I'd google a bit about that error. I don't really know why it's failing
[11:55] <t4nk291> marcos.vnc size is 201841
[11:55] <t4nk291> marcos.avi created is 5682
[11:56] <t4nk291> i record only 10 seconds
[11:58] <Ders> Hmm, I'm sorry. I can't fin what's wrong.
[11:58] <t4nk291> i have no idea how to solve the problem
[12:19] <saedelaere> I have a h264 encoded video from my smartphone and want to scale it down with ffmpeg. But it fails with [AVFilterGraph @ 0x7f644d3b8260] Error initializing filter 'scale' with args '720:flags=0x4'
[12:19] <saedelaere> Here is the complet output
[12:19] <saedelaere> https://bpaste.net/show/f28bb96d6ffa
[12:20] <Ders> you can use -s wxh (for example: -s 1280x720) for downscaling iirc
[12:20] <ubitux> saedelaere: use : for sep
[12:20] <ubitux> Ders: no, don't do that
[12:21] <Ders> ok :p
[12:21] <ubitux> Ders: it will insert a filter, but you don't know if it's at the end or at the beginning of the filtergraph
[12:21] <ubitux> so better explicit the filtergraph yourself
[12:22] <ubitux> anyway -vf scale=720:-1 is what you are looking for
[12:22] <Ders> hmm. Good to know
[12:22] <saedelaere> ubitux: omg, : instead of comma
[12:22] <saedelaere> thank you very much !
[12:22] <ubitux> comma is a filter separator
[12:22] <t4nk291> ubitux
[12:22] <ubitux> you can stack them with a comma
[12:23] <t4nk291> i have this problem http://pastebin.com/dQjkCKQc
[12:23] <t4nk291> i try to do this example from this site  http://panthema.net/2014/vncrec-rgb/
[12:23] <t4nk291> but its not working
[12:23] <t4nk291> any help?
[12:24] <ubitux> i don't know, ask again in 2h if no one helped you, i have to go
[12:24] <t4nk291> the command vncrec  does  -pixel_format rgb24 -video_size 640x480 -framerate 25
[12:25] <t4nk291> ok
[12:37] <Ders> Does anyone know how to use named pipes?
[12:41] <ramiro> Ders: what do you want to do?
[12:42] <Ders> I need to send two streams (an audio and video stream) to an output file
[12:42] <Ders> I think this should be done with streams since they are generated in realtime (and they're not a file)
[12:42] <Ders> I'm using this command at the moment: ffmpeg -r 24 -pix_fmt rgba -s 1280x720 -f rawvideo -y -i \\.\pipe\videopipe -f s16le -ac 1 -i \\.\pipe\audiopipe -vf vflip -vcodec mpeg1video -qscale 4 -bufsize 500KB -maxrate 5000KB OUTPUT_FILE
[12:43] <Ders> But I don't know how to continue
[12:43] <Ders> Could you send me a PM if you have something (I have to go, I'll be back in half an hour)
[13:15] <Ders> @Ramiro I'm back
[13:15] <Ders> Can you still help me?
[13:16] <ramiro> ah, you're on windows
[13:16] <Ders> yes I am
[13:17] <Ders> I need to access those pipes from the command with a windows named pipe so I can send data to them which will then be encoded by ffmpeg
[13:17] <Ders> I want it to be like this: http://blog.mmacklin.com/2013/06/11/real-time-video-capture-with-ffmpeg/
[13:17] <Ders> but with the audio added
[13:17] <ramiro> ffmpeg doesn't support named pipes on windows
[13:18] <Ders> oh... So how do I have to solve this then?
[13:19] <ramiro> if you know C you could add support for ffmpeg to use CreateFile() instead of open() on Windows =)
[13:19] <Ders> I have the thing from the link I sent working for only the video. If I want to add the audio in the same command in the same way, the encoder can never know which data I'm sending
[13:19] <Ders> That would take way too much time
[13:20] <Ders> And I'm not that good at the moment to be adding functions to ffmpeg :p
[13:20] <ramiro> yes, the link uses pipe, it's much easier
[13:20] <Ders> so how do I do that with multiple pipes in the same command?
[13:20] <Ders> I guess I need to be able to tell ffmpeg which data I'm sending (for which pipe)
[13:21] <ramiro> there's only one pipe
[13:22] <Ders> Err... Well, over that one pipe I have, how do I choose which input I'm sending to?
[13:23] <ramiro> what program is generating the streams?
[13:23] <Ders> the video is rendered frame by frame in an rgba-format and the audio is generated using the values of a sine wave
[13:24] <Ders> so it's all raw data
[13:24] <Ders> the video is sent with -f rawvideo as option. The audio uses -f s16le
[13:24] <Ders> Or that's how I want ffmpeg to interpret the data
[13:26] <Ders> At the moment, if I'm only writing the video frames, I'm using fwrite() to write the data to the pipe
[13:34] <Ders> Ramiro: any idea?
[13:48] <Ders> So, if I'm correct this is my question: How do I use multiple stdin to the same ffmpeg command?
[13:58] <ramiro> it's not possible. there's only one stdin per process
[13:58] <Ders> So how do I solve this? Is there another way?
[14:07] <johnvantes> Sorry, I was disconnected so I don't know if my question has been answered or not, so I will repost.
[14:07] <johnvantes> What is the fastest way to create a video with long duration (1 hour), from a single image?
[14:07] <johnvantes> Here is what I have now:
[14:07] <johnvantes> ffmpeg -loop 1 -i image.jpg -c:v libx264 -preset ultrafast -t 3600 -pix_fmt yuv420p -vf scale=640:480 image.mp4
[14:08] <johnvantes> But it's taking too long in my case, around 40 minutes.
[14:08] <tartinette> Hi
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[14:32] <t4nk378> hi i have this problem
[14:33] <t4nk378> http://pastebin.com/amMu1Krx
[14:33] <t4nk378> any help????
[14:36] <PSvils> Hey guys! I'm back again with the same question as yesterday:
[14:37] <PSvils> I'm encoding vp8/webm video from a stream, and the pts is definitely increasing, albeit once in a while it has stutters/larger jumps due to the streams latency.
[14:37] <PSvils> the result is weird webm video where frames seem to jump in time.
[14:37] <PSvils> a frame from +- 2 seconds of the current real time pop up.
[14:38] <PSvils> weird thing is - this isn't consistent. sometimes I can encode video and it plays back normally - this tends to happen on faster machines, and with higher fps video streams.
[14:39] <PSvils> any hints? I thought that as long as the pts value was correct, that I could feed the frames however I want to.
[14:39] <PSvils> (time base is 1 / 1000, so milliseconds)
[14:39] <PSvils> any details I have missed - please let me know! I'm getting a bit desperate at this point :)
[14:40] <t4nk378> i am also desperate but nobody replay me for an answer
[14:40] <t4nk378> http://pastebin.com/amMu1Krx
[14:42] <PSvils> also, if anyone has even a rough idea that I could research myself, it would be of great help, since I'm not even sure where to look at this point. I've verified that the pts is in-line with what I expect it to be.
[15:17] <ecraven> greetings :) does anyone here stream with ffmpeg via mpeg ts to wowza? I'm having trouble, it seems the ingest is working, however the resulting stream has no working video :(
[15:31] <sekon> ecraven: cant you stream with x264 ??
[15:55] <ecraven> sekon: doesn't mpeg ts via udp do that?
[16:23] <DelphiWorld> yo
[16:23] <DelphiWorld> anyone give me ffmpeg git please?
[16:25] <fahadash> #ffmpeg-devel  may be
[16:30] <tartinette> Hi
[17:49] <Ders> Can anyone help me with an audio problem?
[17:51] <__jack__> Ders: the "multiple stdin" you talked about ? use pipes
[17:51] <Ders> No no it's something else
[17:52] <Ders> I have one stdin which should be audio. Is it possible to generate a file from that?
[17:52] <Ders> I'm using this line but it isn't generating a file: ffmpeg -f s16le -i - OUTPUT.wav
[17:53] <__jack__> c_14: awesome
[17:53] <c_14> hmm?
[17:54] <Ders> Ok hold on
[17:54] <__jack__> that shortcuts, humm, brilliant
[17:55] <Ders> Well, The only thing I can show you is that command. There seems to be no output from ffmpeg although, I checked, and I am writing data to the pipe
[17:55] <Ders> to the ffmpeg input that is
[17:58] <fahadash> Ders, There is something like 2 > and 3 > where 2 and 3 are stream numbers
[17:59] <fahadash> people at ##bash can tell you better
[17:59] <Ders> And how would that help my case?
[17:59] <fahadash> You said you had multiple streams to write a file out of ?
[17:59] <Ders> I'm creating a file while writing to it so it's not like I'm writing to an audio stream of a preexisting file
[18:00] <fahadash> brb
[18:00] <Ders> I have this command: http://pastie.org/9942315
[18:01] <Ders> It needs to create an audio file from the data I send it over stdin
[18:01] <Ders> Normally, even if you send faulty data to it, it should create a file. Well, now it doesn't for some reason
[18:31] <DelphiWorld> FFMpegsters
[18:31] <DelphiWorld> how to compile ffmpeg with fpic?
[18:31] <zumba_addict> not really much about ffmpeg but do you guys have any idea how youtube breaks down their videos which makes jumping from one frame to another frame really fast?
[18:39] <__jack__> DelphiWorld: --enable-pic ?
[18:46] <tartinette> Hi
[18:57] <DelphiWorld> zumba_addict: dash
[18:58] <tartinette> Hi
[19:00] <Ders> I'm back
[19:00] <DelphiWorld> Ders: sory! but i'm front ;)
[19:01] <Ders> I have no question :) I was awaiting a response from about an hour ago though
[19:08] <zumba_addict> hi DelphiWorld, just got back to my cube. What is dash?
[19:34] <temhawk> can you create a "film-strip" of all the frames between two certain times?
[19:34] <temhawk> i.e. a PNG or JPG with vertically stacked frames that could be used in a CSS animation
[19:36] <netw1z> how can i use lutrgb to give a video a yellow tint?
[19:36] <netw1z> or lutyuv
[19:43] <llogan> temhawk: see select and tile filters http://ffmpeg.org/ffmpeg-filters.html
[19:44] <llogan> there is a select example using tile in that link
[19:45] <temhawk> llogan: thanks!
[19:57] <voip_> Hello everyone
[19:57] <voip_> I taking live stream with ffmpeg transcoders and pushing to streaming servers.
[19:57] <voip_> If we have network issue (or during restarting streaming server) my ffmpeg transcoders hangs. Its normal behaviour.
[19:57] <voip_> I thinking better way live streams send to 'localhost' then pull them with streaming servers from ffmpeg.
[19:57] <voip_> How to sends tcp streams to local host (HLS or RTMP) ?
[20:04] <temhawk> llogan: the example doesn't work for me, it says "Output file is empty, nothing was encoded (check -ss / -t / -frames parameters if used)"
[20:10] <temhawk> llogan: it's the exact same command as in the example, just with a different file name
[20:14] <llogan> temhawk: please read the complete sentence from fflogger
[20:15] <temhawk> llogan: here's the output: http://pastie.org/private/u60zrvjowlw9eyjbiaiw
[20:15] <llogan> that's not the complete output and your command is missing
[20:16] <llogan> temhawk: how can we improve the message from fflogger to make this easier? it seems that many users can't seem to include the actual command and the complete output
[20:19] <voip_> llogan, hi
[20:19] <voip_> can you help me ?
[20:19] <voip_> I taking live stream with ffmpeg transcoders and pushing to streaming servers.
[20:19] <voip_> If we have network issue (or during restarting streaming server) my ffmpeg transcoders hangs. Its normal behaviour.
[20:19] <voip_> I thinking better way live streams send to 'localhost' then pull them with streaming servers from ffmpeg.
[20:19] <voip_> How to sends tcp streams to local host (HLS or RTMP) ?
[20:19] <llogan> no, sorry. i don't know much about streaming. try the mailing list.
[20:21] <temhawk> llogan: it is the complete output and the command is exactly the same as in the example
[20:23] <llogan> that is not the complete output, and your actual command is a requirement, but i'm done trying to help
[20:24] <__jack__> post the whole command, that's a pre-requierment
[20:25] <temhawk> llogan: http://i.imgur.com/IszZcuq.png
[22:30] <temhawk> llogan: so, you're not going to admit that you were wrong? I told you it was the complete output, and I told you it was the exact same command-line as in the example. don't assume that I'm an idiot.
[22:48] <DayDreamer> Good day people, I've stumbled upon ffserver and there is not really a straight way to download it. Is it released?
[22:49] <JEEB> it's as released as any other binary that's possible to compile from the FFmpeg source code
[22:50] <JEEB> while there is some weirdo minimally maintaining it in FFmpeg, it's still something I really wouldn't use unless really, really desperate
[22:50] <JEEB> a lot of streaming servers can be fed by ffmpeg itself
[22:50] <JEEB> without the need for ffserver being there doing something
[22:50] <DayDreamer> The thing is, i'm looking for a home streaming server, for a closed stream
[22:51] <JEEB> if you want a simple single package, then use VLC
[22:51] <DayDreamer> there was adobe server before which got unpopular and ngix which is scary linux software :D
[22:51] <JEEB> that can not only push to streaming servers, but also serve itself
[22:52] <JEEB> meanwhile if you decide to use a proper streaming server kind of thing, I definitely recommend using ffmpeg as the thing that feeds to it
[22:52] <DayDreamer> never thought VLC could serve  oO
[22:52] <JEEB> it's much simpler to set up :P I used it to stream stuff ages ago with mpeg-ts over http
[22:53] <DayDreamer> wow. that's interesting. basically i want to stream a very special window to 3 people
[22:53] <JEEB> but yeah, I would probably still use ffmpeg + proper streaming server if I was to do a "proper" set up
[22:53] <JEEB> VLC is great for quick hacks
[22:53] <DayDreamer> got any links handy? or just straight go google it :P
[22:53] <JEEB> although I know at least one place using VLC in production
[22:54] <JEEB> (drank some beer with a guy who works at that place=
[22:54] <JEEB> well, you can take a look at the file->export or whatever thing
[22:54] <JEEB> google for more details and I kind of recommend using the 2.2 release candidate builds compared to 2.1.x
[22:54] <JEEB> see #videolan for details
[22:55] <DayDreamer> IRC FTW :D
[22:55] <DayDreamer> lol there are actually many manuals to "vlc as rtsp server"
[22:57] <JEEB> yes
[22:57] <JEEB> I had to test that functionality some time ago when testing an rtsp demuxer for directshow
[22:57] <JEEB> it was just the simplest way to create a stream :P
[22:58] <DayDreamer> i've read there are new protocols for streaming coming, or already there and rtsp is outdated
[22:59] <DayDreamer> HLS i gues
[22:59] <Mavrik> *sigh*
[22:59] <Mavrik> FFMpeg's H.264 decoder doesn't like my FullHD video streams O.o
[23:00] <DayDreamer> I tested WebM with VB8 against h264 - was astonished
[23:00] <DayDreamer> WebM is totaly worth looking into
[23:01] <JEEB> then you have tested libvpx against something shitty
[23:01] <JEEB> Mavrik, inb4 no parameter sets or something
[23:01] <Mavrik> meh I dunno
[23:01] <Mavrik> it doens't complain about missing PSS/SPS
[23:02] <Mavrik> and it manages to startup while reading the stream about 1 time out of 10
[23:02] <Mavrik> I'm ranting though, need to research the issue -_-
[23:02] <DayDreamer> I'm a newbie in codecs world
[23:02] <JEEB> DayDreamer, vp8 is a bad copy of AVC/H.264. and libvpx is a slow reference implementation (albeit kind of usable) which lacks any proper psychovisual optimization
[23:02] <JEEB> libvpx with vp8 is not capable of beating libx264
[23:03] <DayDreamer> sheesh... i need a mentor
[23:03] <DayDreamer> :D
[23:03] <DayDreamer> that stuff is intricate
[23:03] <JEEB> unless you really, really limit libx264, which is not exactly fair. although even in that case libx264 will be much quicker
[23:03] <JEEB> it doesn't help when people post misleading results according to their own agendas
[23:05] <JEEB> vp9 is the same thing with HEVC/H.265 as vp8 with AVC/H.264. So in theory libvpx could beat libx264 with it... except for the missing psychovisual optimizations and the fact that it only very recently got multithreading on the encoding side
[23:06] <DayDreamer> i'm actually in need of a proper explanation about codecs. i'm getting in business of making short videoclips and boy oh boy codecs are driving me nuts
[23:06] <JEEB> for general usage atm it's quite simple as long as you don't have to support plastic toys
[23:06] <DayDreamer> my collegues just suggest me NOT getting into this, because the field is WAST
[23:06] <JEEB> libx264 for video, and depending on the container either vorbis/opus or AAC for audio
[23:07] <JEEB> plastic toys kind of make you learn a bit more but nothing unbearable
[23:07] <DayDreamer> and what's the story with H.265?
[23:08] <JEEB> current gen format, still waiting for the implementations
[23:08] <DayDreamer> so, not usable, right?
[23:08] <JEEB> as in, if you are encoding for low rate scenarios and are OK with 10x or so longer encoding times
[23:08] <JEEB> then it is currently usable
[23:09] <DayDreamer> ah, good for playing around, just not for work
[23:09] <JEEB> (comparing libx265 with libx264 [although they are similar in name, they are developed by completely different people])
[23:09] <JEEB> well, I can see it being useful in low rate VOD
[23:09] <JEEB> although I can also see that real places would rather take the speed and up the bit rate a bit
[23:10] <JEEB> I'll have to make a new test one of these days
[23:10] <JEEB> the last one I did was around december
[23:10] <DayDreamer> it's always like that with Edge cutting techs\
[23:11] <DayDreamer> i'm following octane from otoy.com
[23:12] <JEEB> well, the HEVC/H.265 specification itself is nice, it's just that libx264 was just so darn good. Will take a while until people hone the HEVC encoders to be somewhat usable in all scenarios compared to the previous generation's best stuff :)
[23:12] <JEEB> it took about three or so years with x264, I think?
[23:13] <JEEB> spec released in 2003, and in 2006 it was already quite good
[23:14] <DayDreamer> good things take time :)
[23:16] <JEEB> HEVC's version 1 was released in 2013, and we're entering 2015 now
[23:17] <JEEB> I mostly do non-streaming stuff and I'm OK if compression takes time, so as long as I get my stuff at over 1fps or so, I'm OK with that :D and x265 might be hitting that this year on the settings I'm hitting it at.
[23:18] <spaam> JEEB: enconding your things to vp9?
[23:18] <DayDreamer> any good stuff to read about those? thing is i'm getting paid for making movies and choosing the right codec seems important
[23:19] <JEEBsv> for a general overlook at how video coding works, I recommend "the AVC book"
[23:19] <JEEB> spaam, vp9? ahahaha
[23:19] <JEEB> even with the multithreaded encoding I'm no way going there
[23:20] <spaam> JEEB: so you are waiting for vp10? :)
[23:20] <JEEB> you're good. You can come over and enjoy a bottle of beer with me
[23:21] <JEEB> DayDreamer, this is "the AVC book" btw http://www.amazon.com/H-264-Advanced-Video-Compression-Standard/dp/0470516925
[23:21] <DayDreamer> ah i was just typing about google knowing no "the AVC book"
[23:21] <DayDreamer> thank you :)
[23:22] <JEEB> there's an older version that goes over MPEG-4 Part 2 as well, but that was just a lot of not-so-realistic fluff. basically researchers jerking off in the dotcom bubble
[23:22] <spaam> hahaha
[23:23] <DayDreamer> the world's just full with secrets :D
[23:23] <DayDreamer> so much to be learned
[23:31] <qxt> Hi, Im encoding on a xeon E5-2620v3 (6 cores 12 threads) For some reason in htop I can see that ffmpeg is only using about 85% of the CPU. Is this normal?
[23:33] <qxt> Is this an issue with treading? I am using Debian GNU/Linux stable with a ffmpeg static binary
[23:35] <qxt> Using ffmpeg -i input_file.avi -codec:v libx264 -profile:v high -preset slow -b:v 500k -maxrate 500k -bufsize 1000k -vf scale=-1:480 -threads 0 -codec:a copy output_file.mp4
[23:36] <qxt> with a fps of 83. Is that on the better side?
[23:37] <Lushbits> Hello! I wonder if someone has any experience with using ffmpeg with nginx/rtmp to stream to Twitch.tv or Hitbox.tv? Thanks
[23:41] <kepstin-laptop> Lushbits: not sure what you'd need nginx for; the ffmpeg rtmp can push directly into most streaming services if you build the right rtmp url.
[23:44] <kepstin-laptop> qxt: 480p videos are probably a bit on the small side for exploiting the multithreaded ability of the encoder; you'd probably see more thread usage with a later image size.
[23:45] <Lushbits> kepstin-laptop: yeah, im streaming from another computer to the nginx server. I'm just a bit confused about my settings. Twitch is acting up from time to time about the keyframes.
[23:45] <Lushbits> Then I have to restart the whole stream to make it go away.
[23:46] <Lushbits> using: "ffmpeg -i rtmp:// -vcodec libx264 -preset medium -x264opts nal-hrd=cbr:force-cfr=1:keyint=60 -b:v 2200k -maxrate 2200k -bufsize 2200k -s 1280x720 -sws_flags spline -r 30 -acodec copy -f flv rtmp://"
[23:48] <qxt> kepstin-laptop thx Ill give it a try. Just testing this computer out.
[23:48] <kepstin-laptop> Lushbits: does it work better if you remove the -x264opts and just use e.g. '-g 60' to set the keyframe interval?
[23:49] <qxt> kepstin-laptop, can you give me a cmd that will work the heck out of this cpu ?
[23:49] <kepstin-laptop> qxt: the same thing, but use a 1080p source video and drop the '-vf scale' :)
[23:49] <qxt> thx =)
[23:49] <Lushbits> kepstin-laptop: Havent tried, I'll do that. Thanks! :)
[23:50] <kepstin-laptop> qxt: might as well change the preset to 'veryslow' so it spends more time thinking, too :)
[23:50] <qxt> kepstin-laptop, will do!
[23:51] <kepstin-laptop> Lushbits: yeah, i'm just wondering about that since telling x264 to do cfr might be interfering with ffmpeg's timestamp stuff
[23:52] <Lushbits> ok, I know twitch is really fuzzy about CBR
[23:52] <qxt> kepstin-laptop, now we are talking 98% with very slow
[23:52] <Lushbits> So that might be the reason for the -x264opts
[23:53] <kepstin-laptop> if you want constant framerate, you should probably stick a "-vf fps=<whatever>" in there to let ffmpeg handle it
[23:54] <kepstin-laptop> Lushbits: yeah, it might end up being that you'll have to put the -x264opts nal-hrd=cbr back in, but I wouldn't expect the other two things in there to help with that.
[23:55] <qxt> I have no clue what is a "good speed" with this cmd ffmpeg -i speedtest.1080p.mp4 -codec:v libx264 -profile:v high -preset veryslow -b:v 500k -maxrate 500k -bufsize 1000k -threads 0 -codec:a copy speed_test.mkv
[23:56] <qxt> idk... 24 fps seems ... meh ???
[23:56] <kepstin-laptop> qxt: well, what you do is you pick a setting for -preset that encodes at the speed you want.
[23:56] <kepstin-laptop> it's a encoding speed vs quality tradeoff
[23:57] <kepstin-laptop> 'veryslow' is pretty much the slowest usable option, and is... very slow.
[23:57] <qxt> Oh I dont care about the video. Just testing the cpu. Its a xeon E5-2620v3 6core 12 threads cpu.
[23:57] <qxt> sounds "slow" idk
[23:59] <kepstin-laptop> like, the only way to actually get a comparable fps value from a different system for e.g. a benchmark is to use the same source video, with the same encoding options.
[00:00] --- Fri Feb 13 2015

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