[Ffmpeg-devel-irc] ffmpeg.log.20131012

[burek]

[00:18] <DelphiWorld> hey guys, i'm getting this error while ffprobing a rtmp stream: HandShake: client signature does not match!
[00:18] <DelphiWorld> any clue?
[00:18] <DelphiWorld> this is crtmpserver
[01:31] <alesan> how do I specify the bandwidth with avconv? for the video stream?>>
[01:45] <sacarasc> alesan: #libav is avconv's channel.
[01:46] <alesan> sacarasc, so what is discussed here? I thought it was only an alias
[01:46] <sacarasc> No, libav is a fork of ffmpeg.
[01:46] <sacarasc> They are two projects.
[01:52] <alesan> well my first question was about ffmpeg
[01:52] <alesan> then I saw bubuntu uses avconv so I asked this way
[02:23] <blast_hardcheese> Am I correct in my assessment that ffmpeg will not preserve nonstandard metadata keys from my iPhone when reencoding movies?
[02:24] <blast_hardcheese> I can use -f ffmetadata to look at the metadata, but beyond that it seems ffmpeg doesn't care about it.
[02:35] <blast_hardcheese> It might be fun to write something to re-insert the metadata afterwards, but it's probably something ffmpeg/libav should just do
[04:28] <xingchao_> hi guys, i met an issue on video mosaic, the details is here:http://ffmpeg.org/pipermail/ffmpeg-user/2013-October/017937.html
[04:28] <xingchao_> does anyone could provide some guide?
[04:29] <xingchao_> the issues is from playing some rmvb video with ffplay 0.8
[04:29] <xingchao_> if disable audio, the mosaic disappear
[04:29] <xingchao_> it's really weird
[04:31] <llogan> use a newer ffplay
[04:31] <llogan> and provide a sample in your ffmpeg-user message thread
[04:32] <llogan> (sample input file)
[04:34] <xingchao_> @llogan: yes, the newer ffplay could fix the issue
[04:34] <llogan> that's probably the answer you'll get on the mailing list
[04:34] <xingchao_> the test sample is too big, i cannot upload it
[04:35] <xingchao_> newer ffplay(1.13) could play well, but ffplay 0.8 not.
[04:35] <llogan> if it has been fixed in a newer release (or git head) then is may be possible to backport to an older release if you require an older release (but usage of newer is encouraged)
[04:36] <xingchao_> but based on ffmpleg 1.13, i used android's player, the mosaic issue still exist. that's why i need find out the rootcause
[04:36] <llogan> you can try git-bisect, but i'm not sure how time consuming that would be to test on android
[04:39] <xingchao_> yes, thanks.
[04:39] <xingchao_> when disable audio, the mosaic disappear
[04:39] <xingchao_> @llogan, do you know why this happen?
[04:40] <llogan> i don't know the cause, but from your information it appears to have been fixed. so either use newer ffplay or find the responsible commit(s)
[04:40] <llogan> is the issue reproducable on desktop ffplay 0.8?
[04:41] <llogan> maybe a short sample that shows the issue can be made with dd as shown in http://ffmpeg.org/bugreports.html
[04:42] <xingchao_> okay
[04:45] <llogan> i didn't know RMVB was actually used by anyone
[04:45] <xingchao_> done, i will upload the test files
[04:45] <llogan> is RMVB popular in china? i think i heard that it may be.
[04:46] <xingchao_> yes, a lot of video files are rmvb
[04:49] <llogan> i have to go now, but maybe someone will reply to your mailing list thread later
[04:50] <xingchao_> thanks
[05:32] <xingchao_> i have uploaded the test sample to ftp
[08:16] <MorehouseJ09> is this the correct place to discuss libavformat libraries that ffmpeg uses?
[08:16] <relaxed> MorehouseJ09: yes
[08:19] <MorehouseJ09> relaxed: I'm having trouble applying a bitstream filter. Ever played with those before?
[08:23] <MorehouseJ09> when I call av_bitstream_filter_filter() with the correct args, I'm getting a zero return
[08:23] <MorehouseJ09> while trying to apply the h264_mp4toannexb filter
[14:00] <DelphiWorld> Hi guys
[14:00] <DelphiWorld> how to add two audio stream to a video so user can select the sound input?
[14:01] <Mavrik> look up "-map" in the documentation
[14:15] <xlinkz0> I have this ffserver setup : http://codepad.org/kQVApCq2
[14:16] <xlinkz0> why can't I stream from the ffserver with ffmpeg?
[14:21] <Mavrik> xlinkz0, um, you're defining RTP output not RTSP
[14:21] <Mavrik> and no port
[14:23] <xlinkz0> hmm ok
[14:23] <xlinkz0> just there's an example that uses Format rtp
[14:23] <xlinkz0> and says the stream url is rtsp://..
[14:24] <Mavrik> hmm, that sounds wierd tbh :)
[14:24] <DelphiWorld> thank Mavrik
[14:31] <xlinkz0> Mavrik: changed the conf file to http://codepad.org/wkqbBihD , still can't get anything :(
[14:32] <xlinkz0> the sample ffserver.conf doesn't say anything about stream ports
[14:32] <xlinkz0> http://ffmpeg.org/sample.html
[14:39] <DelphiWorld> xlinkz0: what you're trying to do?
[14:40] <xlinkz0> i'm trying to restream rtsp
[14:40] <DelphiWorld> xtrfrom rtsp to what?
[14:40] <DelphiWorld> xlinkz0: from rtsp to what?
[14:41] <xlinkz0> DelphiWorld: to rtsp
[14:41] <DelphiWorld> xlinkz0: i honestly dont recomand ffserver anymore, i heare is not longer maintained
[14:41] <DelphiWorld> xlinkz0: try out ffmpeg with crtmpserver
[14:41] <xlinkz0> tried crtmpserver in the past, it didn't work
[14:42] <xlinkz0> couldn't stream from it with ffmpeg nor rtmpdump
[14:42] <DelphiWorld> xlinkz0: use svn, work for me
[14:43] <xlinkz0> svn?
[14:58] <DelphiWorld> xlinkz0: checkout crtmpserver from svn, dont install it using your system package manager
[15:00] <xlinkz0> hmm ok
[17:46] <jure> heya
[17:47] <jure> is there a way to normalize audio to a specified amplitude with ffmpeg?
[18:34] <fahadash> What does this error mean "[mov,mp4,m4a,3gp,3g2,mj2 @ 000000000273a5c0] moov atom not found"
[18:34] <Katharsis> hi
[18:34] <Katharsis> how to remove audio delay in my screencast? i'm working on linux (debian)
[18:34] <Katharsis> async/vsync doesn't work
[19:00] <Katharsis> problem fix - i used async + vsync togheter
[21:40] <jure> I'd like ffmpeg to take in a quad-channel wav and output a normalized stereo wav
[21:40] <jure> ffmpeg -channel_layout quad -i input.wav <some normalize filter?> -ac 2 out.wav
[22:04] <dowdle> Ok, when I give -vf scale=xxx:-1 it says it is going to scale as desired in the program output but the resulting video is the original size.  Any idea why it isn't working?
[22:17] <dowdle> ffmpeg version 2.0.2
[22:17] <dowdle> Converting mp4 to webm
[22:17] <dowdle> Output shows: Stream #0:0(und): Video: vp8 (libvpx), yuv420p, 640x438 [SAR 949:800 DAR 26:15]
[22:18] <dowdle> Actual video produced is the original size of 758x438
[22:18] <jure> that's not scaled
[22:19] <jure> shouldn't it be 640x370 then?
[22:19] <dowdle> jure: Yes, calculating it by hand and specifying the y makes it work.
[22:20] <dowdle> jure: So I guess the -1 just isn't scaling it?
[22:20] <jure> it should be afaik
[22:21] <dowdle> Input stream is: Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 702x480
[22:21] <jure> if the input is 702x480, how can you claim the original size is 758x438
[22:21] <dowdle> jure: Ok.  Since I can manually fix it I'm happy.  The -1 has worked for me so much I didn't think it was doing it wrong.  Now I know.
[22:22] <dowdle> jure: IN a player, that's the playback size.
[22:22] <dowdle> jure: But in any case, my statement was incorrect... so use the updated info provided by the input stream output.
[22:23] <jure> could it be that the player's scaling settings are set that way?
[22:24] <jure> you have to pay attention to the sar and dar settings as well
[22:24] <dowdle> jure: If I'm going to have to manually set the sar and dar values I might as well compute the y. :)
[22:26] <dowdle> jure: Or maybe I misunderstood you.
[22:27] <dowdle> jure: In any event, for whatever reason the -vf scale=640:-1 isn't scaling it for me but if I comput the y and put in -vf scale=640:370 then it works.
[22:27] <dowdle> jure: Is there any other setting you are aware of that would make the -1 work?
[22:28] <jure> what about -vf scale=640,-1 ?
[22:29] <dowdle> jure: syntax error on the ,
[22:39] <ubitux> i'm assuming you have multiple -vf or something like this
[22:39] <ubitux> or -c copy maybe
[22:40] <dowdle> ubitux: Ok.  I"ll fpaste it.  Just a minute
[22:43] <dowdle> I guess it is scaling the actual video... but playback adjusts it.
[22:43] <dowdle> VO: [null] 640x438 => 758x438 Planar YV12
[22:43] <dowdle> That's what mplayer -identify says.
[22:44] <ubitux> that's because of aspect ratio
[22:44] <ubitux> you can use sar constants in scale filter for your expressions
[22:44] <dowdle> http://fpaste.org/46380/
[22:44] <dowdle> ubitux: Could you give me an example?  Just copy what is in the input stream?
[22:47] <ubitux> look at http://ffmpeg.org/ffmpeg-filters.html#scale
[22:48] <ubitux> maybe scale=640/sar:-1 or sth like that
[22:49] <dowdle> ubitux: I'll try that.
[22:49] <ubitux> it's likely wrong
[22:50] <dowdle> ubitux: I looked at those docs but I wasn't groking it well enough for my question. :)
[22:50] <ubitux> but use your brain, you should be able to figure it out
[22:50] <ubitux> mine is dead
[22:51] <dowdle> ubitux: Your example worked.
[22:51] <ubitux> ah?
[22:51] <ubitux> i guess it was a lucky guess
[22:55] <dowdle> ubitux: Thanks for your help.  I guess when input videos have odd stretched aspects, obviously scale needs more info to adjust.
[22:56] <dowdle> So how is vp9 support coming? :)  It seems that google is still in the process of optimizing their reference implimentation.  It seems a lot of compression savings can be gained with it but it takes a lot more computational resources.
[22:56] <ubitux> there is a native decoder in ffmpeg
[22:57] <ubitux> and a libvpx wrapper if you need the official implementation
[22:57] <dowdle> ubitux: I've not used ffmpeg (directly) for playback.  That's a different command?  I mainly use gnome-mplayer and vlc... and am ignorant about ffmpeg playback.
[22:58] <ubitux> ./ffplay
[22:59] <ubitux> it's not present in 2.x releases though, see git/master
[23:00] <dowdle> ubitux: So it is only in the devel version?  I've not compiled ffmpeg from source before.
[23:00] <ubitux> no release includes the vp9 decoder yet, so yes you need to build it yourself
[23:01] <ubitux> it's still no optimized btw, we are working on it
[23:01] <ubitux> i mean, it's good enough for most playback on a recent machine, but don't expect to play 1080p smoothly everywher
[23:01] <ubitux> +e
[23:02] <dowdle> ubitux: I periodically go to the webm website's vp9 page and it has a direct link to an ffmpeg search for vp9 stuff... and yeah, I see that.  No one else has it either.  The stock tool they provide requires the original video to be in some weird format... and I haven't figured that out yet.
[23:02] <dowdle> http://www.webmproject.org/vp9/ (link at bottom)
[23:03] <dowdle> http://git.videolan.org/?p=ffmpeg.git&a=search&h=HEAD&st=commit&s=libvpx
[23:03] <dowdle> Or more properly libvpx.
[23:03] <ubitux> libvpx is all about the wrapper
[23:03] <ubitux> see libavcodec/vp9*.c
[23:03] <dowdle> Given the frequency of vp9 updates and the fact that they are still working on optimizations, I would assume everyone is waiting for them to get it (closer to) finalized before they try to support it.
[23:04] <ubitux> bitstream is finalized, they won't change it anymore
[23:04] <dowdle> ubitux: I think I had it all properly setup with their tools once it took a long time for 1 frame.
[23:05] <MorehouseJ09> should avformatcontext have a video_codec field?
[23:05] <ubitux> dowdle: encoding is still extremely slow with libvpx, and last time i tried it wasn't multithreaded so..
[23:06] <ubitux> MorehouseJ09: a format can have multiple video streams, and thus multiple video codecs
[23:06] <dowdle> ubitux: And they are pretty much requiring two pass encoding if I understand correctly.
[23:06] <ubitux> probably, but don't expect a native vp9 encoder in ffmpeg soon
[23:07] <ubitux> a decent encoding for such codec is really hard, and it is often isolated in a dedicated project (see x264 for h264 encoding for instance)
[23:07] <MorehouseJ09> ubitux: definitely. So do I need to manually add that into the output format context?
[23:07] <MorehouseJ09> ubitux: or is it automatically created when I do the avformat_alloc_output_context2() call?
[23:07] <dowdle> ubitux: Any opinion about vp9 vs x265?  I prefer patent unencumbered codecs.
[23:07] <ubitux> dowdle: this is the native decoder in ffmpeg: http://git.videolan.org/?p=ffmpeg.git;a=blob;f=libavcodec/vp9.c;hb=HEAD and wrapper around libvpx for encoding and decoding is in the libvpx*.c files of that same directory
[23:09] <ubitux> dowdle: http://forum.doom9.org/showthread.php?t=167081 http://forum.doom9.org/showthread.php?t=168947 make your own opinion :p
[23:10] <ubitux> MorehouseJ09: i'm not familiar with encoding, check the examples or the appropriate mailing list, or existing working code
[23:11] <MorehouseJ09> ubitux: thanks
[00:00] --- Sun Oct 13 2013