[Ffmpeg-devel-irc] ffmpeg.log.20140320

[burek]

[00:32] <llogan> Kolizer: "ffplay -af volume=0.5 input.foo" worked for me
[03:52] <aaa> How do i get my microphone and "what i hear" to work with avconv? http://pastebin.com/mdPyfUZd
[03:52] <sacarasc> aaa: #libav is the avconv channel.
[03:53] <aaa> ah thanks!
[08:23] <Kolizer> Ask in my stream "twitch.rv/kolizer/" Welcome
[08:25] <Kolizer> " twitch.tv/kolizer/" * sorry
[11:11] <abique> Hello!
[11:11] <caral> hi, I'am trying to compile ffmpeg with x264 support on ubuntu according to this guide https://trac.ffmpeg.org/wiki/UbuntuCompilationGuide But the ./configure of x264 tells me http://pastebin.com/2afLgKZj so x264 is looking at the system wide ffmpeg install. Which option I have to set, that x264 is looking in ~/ffmpeg_build instead of the system wide installation?
[11:13] <abique> Hi, I need a software library to do high performance scaling and cropping of images, would you recommand ffmpeg for that?
[11:14] <Kolizer> "twitch.tv/kolizer/" Welcome
[11:20] <relaxed> caral: x264's ./configure has --disable-lavf
[11:20] <relaxed> caral: always look at "./configure --help"
[11:25] <Max__> I have some dvvideo files that I'm trying to convert to something manageable. It can be lossy, I don't need super high quality. I've tried many (many many) variations of commands I found online, but nothing works "just right". I don't have the video savvy to concoct my own params. Can someone please help me out? This is the file I'm trying to convert: http://pastebin.com/JvQ2SFnd
[11:26] <caral> ah thx, I missed ./configure --help , but I do not want to disable the libavformat support. Now I update the system wide installation, seems atm easier to me ;-)
[11:26] <Max__> I am not particular about container or codec, only that it be viewable and a reasonable size.
[11:28] <relaxed> Max__: ffmpeg -i input.avi -map 0 -vf yadif -c:v libx264 -threads 0 -crf 16 -c:a flac output.mkv
[11:28] <Max__> Thanks.
[11:29] <relaxed> add -preset veryslow for better compression
[11:29] <Max__> What does the -threads flag do?
[11:29] <relaxed> it means use multithreaded encoding
[11:30] <relaxed> also, add -t 20 for a 20 second sample
[11:30] <Max__> What will that do?
[11:30] <Max__> Ah, never mind.
[11:30] <Max__> Thaks.
[11:31] <relaxed> just to test it looks good, etc
[11:31] <Max__> Yeah...
[11:31] <relaxed> Max__: -crf controls the quality size. Raise its value for smaller/lower quality files.
[11:32] <relaxed> er, quality/size
[11:32] <relaxed> -crf 16 should look visually lossless
[11:33] <Max__> This is the new -qp ?
[11:33] <Max__> I found an old command that had -qp 0, and the comments said it went up to 51, being the lowest quality.
[11:33] <relaxed> think of it as a smarter -qp
[11:34] <relaxed> -qp 0 and -crf zero enable lossless mode for libx264
[11:35] <Max__> I'm getting occasional "AC EOB marker is absent" errors. I understand that this is a bug and I should pay it no mind?
[11:36] <relaxed> Don't worry unless it stops
[11:37] <Max__> Video came out good, the two audio streams are corrupt. VLC says that it cannot play the "undf" construct.
[11:37] <Max__> ffmpeg reports them as flac...
[11:39] <relaxed> try -c:a libvorbis -q:a 0
[11:40] <Max__> Hmm... ogg files...
[11:40] Action: Max__ broke several MP3 players trying to get them to play Ogg Vorbis.
[11:41] <relaxed> 0 is low quality, I was thinking libmp3lame
[11:41] <relaxed> use -q:a 5
[11:42] <relaxed> 10 is the highest
[11:42] <Max__> Why isn't there a consistent quality scale?
[11:42] <relaxed> you can use -b:a 160k instead
[11:43] <Max__> That's higher than the input...
[12:02] <Max__> relaxed, thanks for all the help.
[13:43] <hub_> I downloaded the latest ffmpeg and tried 'ffmpeg -f alsa -i hw:0 out.wav' and it give me this 'Unknown input format: 'alsa'
[13:43] <hub_> It's the same with pulse
[13:55] <anshul_> is there any way to see specific frame of mp4 in image veiwer
[13:59] <JEEB> you can use your favourite thing that uses lavf/lavc in a frame-exact way I guess :P one simple way would be by using aegisub for example (which uses ffms2 in the background to load the file in a frame-exact way). If you are interested in making sure yourself that you're actually looking at the exact same picture then a player like mpv and the framestep buttons probably could be helpful?
[14:00] <JEEB> but do remember that if you start comparing pictures you have to make sure they get converted to RGB the exact same way
[14:00] <JEEB> which pretty much means that you have to compare them all in the same thing
[14:19] <anshul_> jebb, i will try, thanks
[14:30] <Aiena> How do I tell ffmpeg to encode all data passing through my soundcard as audio for a video capture from screen ?
[14:31] <Aiena> and JEEB thanks for the upscaling tips
[15:26] <salamanderrake> where did all the presets go for ffmpeg 2.1.4?
[15:29] <JEEB> if you are talking about libx264-related stuff you should switch to x264's internal presets that are available with the -preset option
[15:29] <JEEB> http://mewiki.project357.com/wiki/X264_Settings#preset
[15:35] <salamanderrake> ok
[19:22] <Voicu> hello, is this the right place to ask something related to avformat_open_input ?
[19:30] <llogan> Voicu: yes, but libav-user mailing list may be better for API questions
[19:32] <Voicu> I see
[19:32] <Voicu> well I searched a lot and I'm kinda stuck
[19:32] <Voicu> I might've found something but I might as well ask now
[19:33] <Voicu> I need to read some video data that doesn't come from a file (so avformat_open_input doesn't work)
[19:33] <Voicu> I am now looking into using avio_open_dyn_buf - am I in the right direction ?
[19:34] <Voicu> I'm thinking I can somehow create a context, write the data to it and then to avformat_read_packet on it
[19:36] <synth_> hello
[19:38] <synth_> i'm having issues getting ffmpeg to convert an exr sequence to mov. the command and error i'm getting is at http://pastebin.com/0UdX4fU1
[19:44] <r3c9n> sup
[20:09] <gers4302> I have an an mp4 file with an aac stream in it, ffprobe is showing the following: Audio object type 39 is not supported.  What does this mean?
[20:36] <synth_> i'm having issues getting ffmpeg to convert an exr sequence to mov. the command and error i'm getting is at http://pastebin.com/0UdX4fU1 does anyone know what could be wrong?
[20:41] <JEEB> resolution not specified for the exr file in one way or another
[20:44] <synth_> oh interesting. let me try specifying that.
[20:46] <rsdrsdrsd> I am re streaming an rtmp stream to libx264 and libfdk_aac but I get the following error: missing picture in access unit with size
[20:51] <rsdrsdrsd> I am using the following command ffmpeg -re -i rtmp://localhost:80/live/m1 -c:v copy -c:a libfdk_aac rtmp://localhost:80/hls/m2
[20:57] <synth_> JEEB : I tried specifying the input file size and output and am getting a little bit further, however i'm still encountering errors: http://pastebin.com/tSqkYbXG at the bottom i ran a mediainfo on one of the exr files and it shows the size i specified in the command
[21:17] <rsdrsdrsd> Please can anyone help? I have been busy with it all day and can't fix it
[21:17] <rsdrsdrsd> I also have a bunch of these messages AVC: nal size 21102612
[21:18] <rsdrsdrsd> the rtmp is comming from a flashplayer stream (webcam)
[21:33] <rsdrsdrsd> missing picture in access unit with size 40 , what does that mean?
[21:38] <smo_> hi, i develop an application wich transcode http stream then pipe it to client... i have a problem my client videoplayer reports duration as Nan:Nan any idear ?
[21:39] <smo_> and i tried many formats for ouput only matroska works
[22:13] <rsdrsdrsd> I have version ffmpeg version git-2014-03-20
[22:13] <rsdrsdrsd> it must be a bug or somewhat
[22:13] <maujhsn> Compiling issues?
[22:14] <rsdrsdrsd> no
[22:14] <rsdrsdrsd> i want to transocde an rtmp stream
[22:14] <rsdrsdrsd> to h264 and aac
[22:15] <rsdrsdrsd> I use this command: ffmpeg -re -i rtmp://localhost:80/live/m1 -c:v copy -c:a libfdk_aac rtmp://localhost:80/hls/m2
[22:15] <rsdrsdrsd> I get errors of: AVC: nal size 21102612
[22:16] <rsdrsdrsd> missing picture in access unit with size 40
[22:17] <maujhsn> Can you transcode the stream using gstremer instead?
[22:17] <rsdrsdrsd> Really can't find anything to solve it
[22:17] <rsdrsdrsd> haven't compiled it
[22:18] <maujhsn> Haven't compiled what?
[22:18] <rsdrsdrsd> gstreamer
[22:18] <maujhsn> Goto #gstreamer
[22:20] <rsdrsdrsd> does ffmpeg use gstreamer?
[22:20] <maujhsn> Yes!
[22:21] <maujhsn> The problem with ffmpeg is that you have to have the right branch installed! If you don't then your screwed!
[22:22] <maujhsn> Too many factions...No what I mean!
[22:23] <rsdrsdrsd> what is a goodbranch then?
[22:24] <maujhsn> A needle in a hay stack! :P
[22:25] <maujhsn> Seriously there are good branches out there you just have to ask around!
[22:26] <rsdrsdrsd> which one do you advice?
[22:27] <maujhsn> Unfortunately The one I would recommend I wouldn't part with it if my life depended upon it!
[22:28] <maujhsn> But if you do a search "ffmpeg + fakeoutdoorsman" He had great branches years ago!
[22:29] <maujhsn> The latest stuff I wouldn't touch with a ten foot pole!
[22:30] <rsdrsdrsd> why not?
[22:30] <rsdrsdrsd> are they so bad?
[22:32] <synth_> i'm having issues getting ffmpeg to convert a exr sequence to h264 and retain the same colorspace used in the exr sequence. when looking at the generated h264 in linear space, it appears that it's been lifted slightly, however if i use mjpeg, i get an almost identical result to the exr sequence
[22:33] <maujhsn> rsdrsdrsd You go with a brand or branch that you can trust!
[22:35] <maujhsn> rsdrsdrsd Tell you what, I am considering trying this guys branches! https://ffmpeg.org/download.html#release_2.0
[22:37] <rsdrsdrsd> you mean the static builds?
[22:39] <maujhsn> Quality Control?
[22:40] <rsdrsdrsd> well let's try to recompile
[22:42] <maujhsn> Hint: If anyone is willing to speak up about this guys work...I'm all ears!  https://ffmpeg.org/download.html#release_2.0
[22:47] <maujhsn> rsdrsdrsd Are you using libav  or ffmpeg?
[22:54] <rsdrsdrsd> ffmpeg
[00:00] --- Fri Mar 21 2014