[Ffmpeg-devel-irc] ffmpeg.log.20120405

burek burek021 at gmail.com
Fri Apr 6 02:05:02 CEST 2012


[01:34] <lesshaste> ubitux, yes the first frames are bad!
[01:34] <lesshaste> ubitux, why is that?
[01:38] <mischanix> I'm trying to stream directshow inputs encoded with x264/lame to rtmp.  However, rtmp seems to bottleneck above ~1Mb/s, even if I stream to a LAN rtmp server (connection is 100Mb).  Streaming to file, no frames are dropped, but using rtmp, the buffer fills up and frames are dropped wildly above 1Mb.  Using zeranoe's windows builds, have tried both x86_64 and x86 versions.  http://pastebin.com/SNT0iiHJ
[01:39] <burek> mischanix, try vlc
[01:41] <mischanix> Does vlc's librtmp work yet?
[01:42] <mischanix> I mean, I tried to make that work at first to no avail.
[01:42] <burek> well, since you are trying windows builds, I'm pretty sure you're going to hit the wall sooner or later :S
[01:42] <burek> btw, why do you need rtmp
[01:42] <burek> any specific reason?
[01:43] <mischanix> Trying to work around XSplit for justin/twitch/own3d so that a friend can stream without it if possible.
[01:45] <burek> did you try raising -rtbufsize 10000000 param?
[01:46] <mischanix> Yeah.  I've had the buffer up to 4 GB in memory and the same thing happening
[01:46] <mischanix> [Windows doesn't like that.]
[01:46] <burek> also, you are using high resolution -s 1280x800 -r 24
[01:46] <burek> combined with -crf 20
[01:47] <burek> it's pretty cpu intensive
[01:47] <burek> can you try, just for test to use -s cif
[01:47] <burek> that's lower than vga (640x480)
[01:47] <burek> just to see if it's a cpu issue
[01:48] <burek> (also remove -s and -r before the output if it's the same as in input)
[01:48] <mischanix> Yeah, cpu maxes at 65% or so using rtmp.
[01:48] <mischanix> 100% flv.  Using crf /40/ works better, but obviously the quality is meh.  default crt, rtmp starts to bottleneck again
[01:48] <burek> although, dshow shows those warnings, which means probably a bad driver or something, not sure..
[01:49] <burek> it doesn't even get to the encoder when the warning is raised
[01:49] <burek> try using maybe -crf 23 (default) and also use -preset ultrafast
[01:51] <mischanix> drops even more with cif.
[01:52] <burek> maybe you didn't remove -s and -r before the output
[01:52] <mischanix> Er, that was using vb 3500k though
[01:52] <burek> so it tries to rescale from cif to that
[01:54] <mischanix> Smooth as butter with crf 20
[01:56] <burek> now, try increasing -s
[01:57] <burek> to see what is the pitch top for your machine
[01:58] <mischanix> 1280x800 with crf 30 is smooth
[01:58] <mischanix> But this is with about 34% going to another program
[01:58] <burek> well, screen grabbing and encoding is really cpu intensive
[01:59] <burek> so you should use some codecs optimized for screen grabbing (low cpu usage, but bad compression)
[01:59] <burek> of course, if you need live stream
[01:59] <burek> if not
[01:59] <burek> then do it in steps
[02:01] <mischanix> crf 28 1280x800 is about 55%
[02:02] <burek> :)
[02:09] <mischanix> so, using -maxrate 3500k -bufsize 3500k uses less CPU and drops more frames, but -maxrate 1500k -bufsize 3000k uses more CPU and drops less frames, even though the connection is 100Mb.
[02:10] <burek> that doesn't have anything to do with the network connection :)
[02:11] <burek> but with the desired output bitrate that you want
[02:11] <burek> higher bitrate / less encoding / less cpu / less encoding time
[02:11] <mischanix> In fact, with every setting I've tried, the dropping of frames has been proportional to the bitrate.  Is that how it should be?
[02:12] <jya> a very silly question, but I'm yet to find an answer& with ffplay how do you select which alsa audio device to use? I get no audio by default
[02:12] <mischanix> i.e. lower bitrate -> fewer dropped frames. That doesn't make sense to me.
[02:12] <burek> well, would you drop more plates if someone would throw them at you, like, 10 in a second or 1 in a second? :)
[02:13] <burek> jya, did you read ffplay documentation? :)
[02:13] <jya> I did...
[02:13] <jya> if you find anything related to audio output device in there, you're good :)
[02:14] <burek> mischanix, why doesn't it make sense
[02:15] <mischanix> burek, CPU isn't my bottleneck.  If I output the same settings to a local file, very few if any frames are dropped.  However, when rtmp is introduced, bitrate becomes proportional to frame dropping.  In the situation of outputting to a local file, the opposite is true until around 100MB/s
[02:15] <jya> burek: I've been googling for a good 20 minutes on the matter, read all the manpages, and ffplay -h .. nothing in regards to audio output device
[02:16] <burek> jya, just a sec
[02:17] <burek> mischanix, I think the best chance would be to find the irc channel for librtmp developers and ask them directly
[02:18] <burek> ffmpeg just uses its interface
[02:18] <mischanix> Yeah, but if I were in their shoes, I'd just dismiss it as an issue with the cross-compiler toolchain
[02:18] <burek> :)
[02:20] <mischanix> But, yeah.  I suppose I'll look around their parts of the internet now.  Thanks for the insight :)
[02:21] <burek> np :)
[02:22] <burek> jya, so, you want to select a specific audio output, right? :)
[02:22] <jya> well, I just want to play audio.. I get no audio by default. so I'm guessing it's to do with an issue with the default audio device.
[02:23] <jya> ffplay file.mpeg give me no audio
[02:23] <jya> so I was hoping that specifying the alsa audio device might help. similar to -ao in mplayer
[02:24] <burek> did you check if file.mpeg has audio streams in it? :)
[02:24] <jya> of course it has audio :)
[02:24] <burek> ok :) well
[02:24] <burek> you can always use alsamixer
[02:25] <burek> and with f6 choose the default device
[02:25] <jya> reason I'm trying ffplay is because I want to find when ffmpeg fixed a bug in AAC-latm decoding.
[02:25] <burek> or f5
[02:25] <jya> alsamixer doesn't let you configure your default audio device
[02:26] <burek> since when
[02:26] <jya> since forever
[02:26] <burek> o.O
[02:26] <burek> did you even try it
[02:27] <jya> it only let you define the mixer level& f6 let you define what audio device to use, for within alsamixer.
[02:27] <burek> :)
[02:27] <burek> ok
[02:27] <jya> fwiw, i'm quite well aware of what alsa does and .. what it doesn't :)
[02:28] <jya> hum&. activating pulse audio gives me audio in ffplay for some reason.. this will let me go by for the time being
[02:28] <burek> :)
[02:29] <jya> i find it amazing that ffplay doesn't have an option to set the audio output device
[02:29] <jya> I certainly don't want to use pulse
[02:43] <jya> git bisect isn't going to help me much& ffmpeg at the time of the last sync doesn't play that file anywhere like what mythtv does. myth has slight corruption every few seconds, ffplay play that file at extremely low speed
[02:46] <jya> wrong window
[03:45] <entreri> hello, is there a way to disable the need of an X server for ffplay ? I don't want to depand on X to play an mp3, and I do not need any graphic, any idea ? thanks.
[03:47] <burek> did you ever try something like this: ffmpeg -i play.mp3 -acodec copy -f alsa hw:0
[03:52] <jya> entreri: use -nodisp
[03:52] <jya> ffplay -nodisp file.mp3
[03:54] <entreri> jya: I tried but it seems I still need to specify a display, it seems to just disable the graphic animation in X
[03:54] <entreri> "Unable to open mouse, Did you set the DISPLAY variable?"
[03:54] <jya> entreri: I use this command on a headless server to play audio ...
[03:54] <jya> what version of ffmpeg are you using?
[03:55] <entreri> 0.10.2
[03:58] <entreri> I think I need to change the config, there are some switches initialised, one of them is --enable-x11grab
[04:16] <66MAAA5MI> hello all
[04:17] <66MAAA5MI> is there a ppa for ubuntu?
[04:17] <66MAAA5MI> ah, found it
[04:17] <66MAAA5MI> https://launchpad.net/~jon-severinsson/+archive/ffmpeg
[04:23] <Shimmy> Hi everyone, is this a developer channel?
[04:39] <Shimmy> Anyone in here?
[06:21] <fling> hello! :p
[06:22] <fling> can I capture from BlackMagic DeckLink SDI ?
[06:22] <relaxed> fling: is there a v4l2 driver for it?
[06:22] <relaxed> If so, yes.
[06:36] <Shiron> Wow...lots of users...
[06:36] <Shiron> Anyone active?
[06:37] <Shiron> Hello...anyone here?
[06:38] <Shiron> Knock knock...
[06:40] <relaxed> do you have a real question?
[06:42] <Shiron> Several. A lot.
[06:43] <Shiron> Actually I have absolutely no experience with ffmpeg, but I really could use some help.
[06:45] <Shiron> Right...
[06:46] <relaxed> Help with what? Ask a specific question...
[06:46] <Shiron> So, I've only ever used GUIs up until now. The most specific I can get is that I've just downloaded a windows guild of ffmpeg on its own and I have no idea how to run it.
[06:46] <Shiron> *build
[06:47] <relaxed> start -> run -> type "cmd.exe"
[06:47] <relaxed> enter
[06:47] <Shiron> Yes
[06:48] <relaxed> navigate to the binary and run it.
[06:48] <Shiron> Alright...
[06:48] <Shiron> Is it already configured with all the libraries?
[06:48] <Shiron> Zeranoe build
[06:48] <relaxed> I think he offers static builds, so yes.
[06:49] <relaxed> what is your goal?
[06:50] <Shiron> Recompiling an SBS .avi into actual 3D output
[06:50] <Shiron> I have the code
[06:50] <Shiron> I just don't know how to run it
[06:50] <Shiron> You put it in a .bat, right?
[06:53] <relaxed> this script has ffmpeg commands in it?
[06:53] <Shiron> -i -vol -s
[06:53] <Shiron> Yes, I believe
[06:54] <relaxed> then modify the script and use the full path to ffmpeg and the input I guess
[06:55] <relaxed> I don't use windows, nor do I know how to script for it.
[06:55] <Shiron> Yes, I've figured as much
[06:56] <Shiron> But the internet cafe I'm in only allows for one IP, so I'm unable to run an internet browser to download ffmpeg in my Ubuntu VB
[06:59] <Shiron> You know...
[06:59] <Shiron> I should just start in a NAT...
[06:59] <Shiron> Whoops. Be back soon?
[07:06] <Shiron> Alright, what's the apt-get for ffmpeg? Still new to Linux.
[07:11] <Shiron> know what, nevermind.
[07:11] <Shiron> General unresponsiveness has really peeved me.
[07:12] <Shiron> Thanks anyways, and good day.
[07:55] <TACPILOT> what container handles RGB32 ??
[08:44] <orangey> hello all
[08:45] <orangey> I'm having an absolutely infuriating time with ffmpeg. I'm making some videos with kdenlive in h264 or xvid or mpeg2, and they render with a/v sync issues
[08:45] <orangey> I cannot for the life of me figure out *why*, nor correct the issues
[08:46] <orangey> how do I even debug why the sync issues are arising?
[09:39] <level09> I am converting my video to h264 file but for some reason I cant run it using html5 video player
[09:39] <level09> what am I missing here ?
[09:41] <level09> mix_cmd = 'ffmpeg -y -i input.f4v -vcodec libx264 -b 512K -threads 0 -preset fast  -acodec libmp3lame  -crf 20  out.mp4'
[09:45] <thebastl> anyone in here using ffmpeg on android?
[09:45] <thebastl> hi btw
[09:46] <level09> hey
[10:12] <cbreak-work> so... I'll try to link ffmpeg to my application on windows. Wish me luck.
[10:13] <sacarasc> You can do it, cbreak-work!
[10:33] <matt__> Hi, i' trying to decode Subtitles in the dvbsub format. I decode them using the avcodec_decode_subtitle without any problem. I need to reconstruct the image and save it. My problem is that i cannot understand how the image is stored (pix_fmt is -1) and i cannot find any documentation. Can you explain to me how the data is represented or tell me where i can find the info please?
[10:36] <cbreak-work> sacarasc: thanks, it works! :)
[10:36] <cbreak-work> was less trouble than I expected
[10:36] <sacarasc> Of course it does, you have work in your nick!
[10:37] <cbreak-work> linking a C library is so much nicer than C++ on windows
[10:53] <burek> orangey,
[10:53] <burek> can you please use pastebin.com, to show your command line and its output?
[10:54] <burek> matt__, did you try asking your question in #libav ?
[10:56] <matt__> no i didn't try on libav, i will give it a shot then
[10:56] <matt__> Do you have an idea on how the data is organised?
[10:58] <burek> no, sorry :)
[10:58] <matt__> Arff, no problem. Finding appropriate documentation is quite hard!
[10:59] <burek> :) at least you are not bored :)
[11:00] <matt__> Yeah sure ^^
[11:00] <buhman> is it possible to multithread anything fancier than mpeg2?
[11:01] <buhman> like say vp8 or h.264?
[11:01] <burek> buhman, h264 :)
[11:01] <burek> -threads
[11:08] <buhman> hmm, my distribution's ffmpeg only seems to come with 7 ffpresets
[11:10] <burek> buhman,
[11:10] <burek> can you please use pastebin.com, to show your command line and its output?
[11:10] <burek> just type ffmpeg
[11:16] <buhman> burek: http://sprunge.us/ZXWV
[11:16] <burek> that's ok
[11:16] <burek> anyway
[11:17] <burek> instead of vpreset
[11:17] <burek> ffmpeg now uses native x264's -preset option
[11:17] <burek> so type x264 --help
[11:17] <buhman> O.o oh really
[11:17] <burek> and read about -preset -profile and -tune
[11:17] <buhman> when did that happen?
[11:17] <burek> recently
[11:17] <burek> several months ago :)
[11:20] <buhman> O.O watching my new hyperthreaded 2 CPU quad core doing ffmpeg -threads 0 in htop
[11:20] <buhman> that's pretty sexy
[11:21] <burek> :)))
[11:21] <burek> you could do live screencasting in hd :)
[11:21] <buhman> particularly the part where I'm doing 65fps on the slow preset on 480p video
[11:21] <buhman> right; that's what I was bout to say
[11:22] <buhman> I could do not-slow and get away with 720p probably
[11:22] <burek> you can try :)
[11:23] <buhman> linpack told me 65 GFLOPs
[11:23] <buhman> is that "good" in the spectrum of computers that are used to encode h.264 video?
[11:24] <burek> there are some better things, like hardware encoders :)
[11:24] <burek> and way cheaper
[11:25] <buhman> O.o really?
[11:28] <buhman> I mean, considering my last computer was only 0.8 GFLOPs (linpack), I was afraid I was going to make a mess in my pants when I compiled ffmpeg-git (just a few minutes ago) in 1 minute and 57 seconds (according to 'time')
[11:31] <burek> cool :)
[11:31] <burek> do you have ssd disk
[11:54] <luc4> Hi! I'm using ffplay to play an mp3 on a http server but I noticed the AVERROR_EOF is never received from av_read_frame. For any file I place on that server. Anyone who experienced the same?
[11:55] <burek> you can try asking your question in #libav too
[11:55] <luc4> burek: thanks
[12:22] <libv> libav sws_scale colour space question...
[12:23] <libv> i am hacking together some tool to do better test kms planes (and it will also gain Xv support)
[12:23] <libv> converting from RGB24 to 0RGB (as needed by the overlay) manually gives me nice blacks
[12:24] <libv> using sws_scale with the defaults gives me blue.
[12:25] <burek> you can try asking your question in #libav too
[12:27] <libv> *sigh* forks are fun (said the guy who lived through part of the xfree86/X.org shit)
[15:04] <kriegerod> is there, at iOS AVFoundation API, http://goo.gl/EWZ5J , among kCVPixelFormatType_*, some format that exactly matches libavcodec's PIX_FMT_YUV420P? Or which of formats from AVFoundation matches exactly to particular libavcodec pixel format, so i can convert it with swscale?
[15:07] <burek> you can try asking your question in #libav too
[15:09] <plm> Hi all
[15:24] <kriegerod> burek, thanks captain, i've already done it )
[15:28] <burek> :beer: :)
[15:29] <plm> how works (in low level) to sent video streaming via http? I think that sen streaming via http is hirrble, because http will back, from target, to source, the response for each POST/GET.. that are there the peace of video right?
[15:30] <burek> plm, if you use each http request for each peace of video, well, yes, that will work slow :)
[15:30] <burek> but why would you do that? :)
[15:31] <burek> usually 1 http request/response is enough to start http streaming
[15:31] <burek> piece*
[15:31] <burek> lol peace :D
[15:32] <plm> burek: sorry, just curous how taht works over http
[15:32] <burek> well, you would use ffserver + ffmpeg
[15:32] <plm> burek: so how really works, dont have repose for each post/get? or dont have post/get in that?
[15:32] <burek> client does http request, server replies with http response + stream data
[15:33] <burek> and the connection stays open indefinitely
[15:33] <burek> (if it's a live stream for example)
[15:34] <plm> burek: ok, and will have this request/response for each pieace of video stream?
[15:35] <burek> each piece?
[15:35] <burek> what is a piece?
[15:36] <plm> burek: if is live stream.. that live stream has a prt of video....
[15:36] <burek> read my previous 5 lines
[15:37] <burek> server sends stream data as it gets encoded
[15:37] <burek> through the same tcp connection
[15:37] <burek> it is all 1 http request/response
[15:37] <plm> burek: I read that. After server replies with http response + stream data what happen?
[15:37] <plm> burek: ohh
[15:37] <plm> burek: just one request;respose, in start video only?
[15:37] <burek> well, during time, client continues to receive stream data
[15:38] <burek> connection stays open forever, and client receives stream through it
[15:38] <plm> after is just tcp, without http right?
[15:38] <burek> well, yes
[15:38] <burek> it is data with undefined length
[15:38] <burek> so the client keeps receiving it
[15:39] <plm> burek: ok. I was thinking that as is over http, the request/respose will have everytime.. not just in start connectiion...
[15:40] <plm> burek: and after receiving video, are the http still working, been used in this moment.. like as video still send via http protocol, or will use just in start connection?
[15:41] <burek> server sends http response + stream data (forever)
[15:42] <plm> burek: ok. But request is not send never more by client right?
[15:42] <burek> correct
[15:42] <plm> burek: thanks for clarify!
[15:42] <burek> :beer: :)
[15:43] <plm> burek: so that is not so heavy!
[15:43] <burek> not at all :)
[15:43] <plm> burek: just somes bytes more in response..
[16:05] <woozly> guys, how to copy metadata to file, on convert?
[16:05] <woozly> metadata with duration (because video-js player html5/js waits until videofile downloaded)
[16:07] <burek> try mediainfo
[16:09] <woozly> can map_metadata help me? :)
[16:09] <woozly> what is mediainfo?
[16:10] <zimbatm> woozly: mediainfo is another tool that shows you media metadata
[16:14] <woozly> zimbatm, oh.. good. thank you!
[16:14] <woozly> burek, thanks!
[16:55] <orangey> hello all
[16:55] <orangey> I'm having some trouble with this command and a video with an AAC audio input: ffmpeg -i In.mp4 -strict experimental -vcodec copy -acodec copy -ss 00:00:00.1 -t 10 -an output.mp4
[16:55] <orangey>     Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 48000 Hz, stereo, s16, 353 kb/s
[16:55] <orangey> but the output is sans audio
[16:57] <burek> orangey,
[16:57] <burek> can you please use pastebin.com, to show your command line and its output?
[16:58] <orangey> http://pastebin.com/WJ7qaxA2
[16:58] <orangey> burek
[16:59] <burek> ok
[16:59] <burek> also, you only need -strict experimental if you are encoding audio with aac
[16:59] <burek> if you use -acodec copy that's not needed
[17:00] <burek> since no encoder is being used
[17:00] <burek> the data is just copied
[17:00] <orangey> burek: I figured as much, but since it wasn't getting copied and I know my incoming is aac, I figured I'd try it
[17:01] <burek> remove -an
[17:01] <burek> that means "audio none"
[17:01] <Mavrik> yeah, "-an" disables audio on output
[17:02] <burek> you can see in your output after the line: Output #0, mp4, to 'output.mp4':
[17:02] <burek> look into all lines that begin with: Stream #
[17:02] <burek> that'll show you streams in the output file, so you can see there is no audio
[17:19] <orangey> ooh/
[17:19] <orangey> oops. thank you
[18:04] <miknix> hello everybody
[18:05] <miknix> does someone know if the libx264-normal preset was added after ffmpeg-0.7.8 or removed before that?
[18:05] <miknix> I cant find that present in that version
[18:08] <jermy> I think ffmpeg dropped x264 presets before then - we had to move to using the x264 preset names directly at some point
[18:34] <meekohi> OSX: I have libx264 installed via macports and trying to ./configure --enable-libx264, but getting "ERROR: libx264 not found"
[18:36] <meekohi> Any ideas how to get this working? libx264 doesn't compile for OSX seemingly.
[18:44] <miknix> jermy, I see, so I can consider the normal preset as deprecated
[19:52] <Radex> Hi, i getting Unrecognized option 'directpred'
[19:53] <Radex> it's deprecetad option i new one ffmpeg version?
[19:55] <Radex> s/i/in
[20:09] <iive> Radex: direct_pred ?
[20:10] <meekohi> I switched to homebrew. Had some problems but finally got it working.
[20:10] <iive> looks like x264 option.
[20:13] <Radex> iive: yeah, just found commit in git - thanks for help
[20:55] <burek> meekohi, you need libx264-dev, not libx264
[20:55] <burek> miknix, just use -preset option in ffmpeg and type x264 --help to see more info on -preset -profile and -tune
[20:56] <burek> those options are mapped directly to native x264 options
[20:56] <burek> so you can use its help screen
[20:58] <andrew_> Hey again, im getting a similiar option
[20:59] <andrew_> not option, problem
[20:59] <andrew_> sorry
[21:00] <andrew_> I try normal syntax, "ffmpeg -i <input> <output>
[21:00] <andrew_> I get errirs about broken ffmpeg default settings and asking me to use -vpre
[21:00] <andrew_> but those don't work
[21:01] <andrew_> any ideas?
[21:33] <lanceio> PSP decent quality?
[21:33] <lanceio> FAQ?
[21:34] <JEEB> lanceio, http://x264.fushizen.eu/random/psp_encoding.txt
[22:26] <Mista_D> where can I upload a sample file? mediafire seems to be down...
[22:28] <Mista_D> FFmpeg 0.1.2 fails to decode MOV with LPCM 24bit audio 48 kHz, stereo... http://www.mediafire.com/?52cdkuqf8w4f431  Any advice on how to encode it to flash?
[22:35] <juanmabc> when something fails i encode intermediarily to mp4
[22:40] <Aegwyn11> I have an transport stream with h.264 video that I'd like to decode to raw video in AVI. The source material is 29.97 1080i TFF, but it seems that the output raw video file is always progressive. How do I flag it do that the output AVI is interlaced?
[23:01] <meekohi> Does anyone know how to debug the error: "%03d.jpg: could not find codec parameters" ?
[23:02] <meekohi> I feel like I need to add something to ./configure, but don't know that.
[23:03] <meekohi> That error comes from ffmpeg -i %03d.jpg out.webm by the way
[23:06] <meekohi> --enable-decoder=mjpeg maybe?
[23:07] <beastd> meekohi: no it should be enabled by default with a normal ffmpeg build. i try to reproduce your problem now.
[23:07] <meekohi> beastd: I'm starting from --disable-everything in configure
[23:07] <meekohi> beastd: I only want the bare minimum (have to compile when bringing new server online)
[23:08] <iive> meekohi: i don't see framerate
[23:08] <iive> hi beastd
[23:09] <beastd> meekohi: than mjpeg is needed
[23:09] <meekohi> Ah okay sorry I shortcutted: /usr/local/bin/ffmpeg -i "%03d.jpg" -g 3 -r 30 -b:v 2.0M -y out.mp4 2>&1
[23:09] <beastd> Oi iive!
[23:09] <meekohi> Do I just need the decoder? Do I need "demuxed" too?
[23:10] <beastd> you need img2 demuxer and mjpeg at least
[23:10] <iive> meekohi: unless you have disabled things specifically, you should have everything you need for jpg decoding.
[23:11] <beastd> iive: [23:07:32] <meekohi> beastd: I'm starting from --disable-everything in configure
[23:11] <iive> oh...
[23:11] <iive> bad idea :)
[23:11] <beastd> :)
[23:11] <meekohi> Yeaaah I know ::ashamed:: I'm trying to speed up the time to bring new servers up& might be shooting myself in the foot.
[23:11] <iive> with cannonball
[23:12] <iive> if you have multiple cores, build with `make -j4` for 4 cores.
[23:13] <beastd> meekohi:  img2 is named image2
[23:13] <meekohi> iive: only one core for now, doing this on EC2
[23:13] <iive> ec2?
[23:13] <meekohi> okay I've added image2 mux/demux and mjpeg encode/decode
[23:13] <meekohi> Amazon cloud
[23:14] <meekohi> They don't package ffmpeg nicely for you unfortunately :(
[23:14] <beastd> meekohi: you probably do not need encode/mux if I understood your usecase. though it won't hurt in any case.
[23:14] <iive> what is the default encoder for webm?
[23:15] <iive> vp8?
[23:15] <meekohi> vpx I think?
[23:15] <meekohi> I added that and h264 as well.
[23:15] <iive> is it libvpx or ffmpeg have an encoder?
[23:15] <iive> i know we have decoder, quite faster than the official.
[23:15] <meekohi> No idea.
[23:17] <meekohi> Okay I will get rid of --disable-everything and try working backward instead...
[23:17] <beastd> meekohi: what was missing after enabling mjpeg and image2?
[23:18] <meekohi> Says Unable to find suitable output format for .mp4, which is weird because this was working before I think.
[23:21] <meekohi> What does the muxer/demuxer do exactly in the case of jpegs?
[23:23] <beastd> The "demuxer" makes the bunch of jpegs into a video stream.
[23:24] <beastd> The image2 "muxer" would do the opposite and create a series of jpeg image files from a video stream
[23:26] <JEEB> <iive> is it libvpx or ffmpeg have an encoder? <- libavcodec only has a decoder, the encoder's libvpx
[23:26] <JEEB> there's also a xvp8 under work
[23:29] <beastd> meekohi: seems unlikely to me but you could try once more with disabled image2 muxer. if that doesn't work again you are probably missing the muxer for your desired output format
[23:29] <iive> JEEB: i think at some point the x262, x264, x265 and xvp8 would merge, forming a new common encoder library.
[23:30] <JEEB> lol
[23:30] <iive> :P
[23:30] <JEEB> x265 is the only one I haven't seen yet
[23:30] <beastd> try to verify it is compiled in with ffmpeg -formats
[23:30] <iive> I heard the standard is out of draft stage and is (almost) ready.
[23:31] <JEEB> yeah
[23:31] <JEEB> so in theory one could start watching out for changes in the JVT mailing list
[23:31] <JEEB> and making some pre-work
[23:35] <ckb> How should I decide what presets to use?
[23:37] <JEEB> libx264?
[23:37] <ckb> yes
[23:37] <JEEB> http://mewiki.project357.com/wiki/X264_Settings#preset
[23:37] <JEEB> basically select the slowest you can take
[23:39] <ckb> okay, and running concurrent ffmpeg processes isn't a great idea, right?
[23:40] <JEEB> in most cases
[00:00] --- Fri Apr  6 2012


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