[Ffmpeg-devel-irc] ffmpeg.log.20130816

[burek]

[00:02] <luc4> still 2.0.8 is not working on that file
[00:02] <mark4o> hmm... works for me
[00:02] <mark4o> maybe something else wrong with your file
[00:03] <luc4> mark4o: maybe& the command line I used and the output is on pastebin
[00:04] <llogan> why are you re-encoding the video?
[00:06] <luc4> llogan: video is baseline, I want it high profile. Audio I'd prefer it ac3.
[00:06] <llogan> anything that supports high should be able to support baseline
[00:07] <llogan> unless it's retarded
[00:09] <luc4> I don't quite understand why the reasons matter techically, anyway, high profile takes less bytes, doesn't it?
[00:09] <mark4o> yes, reducing the size by 3.4x seems like a good reason to me
[00:10] <luc4> precisely
[00:13] <mark4o> luc4: I would recommend using 32k, 44.1k, or 48k sample rate for ac3, if you want it to be compatible with more players
[00:13] <mark4o> but if you want to debug 16k sample rate on vlc you could try encoding just a simple tone or something and play it
[00:14] <mark4o> ffmpeg -f lavfi -i sine=b=4:r=16000 -acodec ac3 -t 5 out.mp4
[00:21] <luc4> mark4o: I would really like to enter the implementation details of vlc, but unfortunately I'm already working on a thousand projects :-) just wanted to know if this was something to report to ffmpeg or not. Not trying to solve a spefic problem with a specific file (I'm keeping it only as a way to reproduce the "issue"). As it really seems not related to ffmpeg, I'm throwing it away. Thanks guys!
[00:21] <mark4o> np
[00:41] <llogan> luc4: then you can degrade the quality and have to wait for encoding
[00:42] <luc4> llogan: sorry?
[00:43] <llogan> your input is already H.264 but you are re-encoding it.
[00:45] <luc4> llogan: if it is possible to compress by the same factor without re-encoding it then I might be interested, anyway, I repeat again: the only reason I'm interested in this file is because it could reproduce a possible issue. As I see there is no issue in ffmpeg, case is closed. Anyway, still interested if compressing more without re-encoding is possible, but not related to that specific file.
[00:47] <llogan> -codec:v copy
[00:48] <luc4> llogan: isn't that supposed to simply copy the video stream?
[00:49] <mark4o>  llogan: there are many benefits to a smaller file size, e.g. if you are putting it on a web site, or emailing it to a bunch of people, or trying to fit as much as possible on a disc
[00:49] <mark4o> not everyone is encoding videos only for their personal consumption
[00:56] <luc4> llogan: if there is a better way to make a video file >= 6GB become ~= 600MB without visible differences& then I'm really interested& otherwise, the meaning of this conversation is not clear to me& unless someone is giving away unlimited disk space or hard drives for free& in that case maybe& well, maybe neither&
[00:57] <luc4> llogan: oh, btw, the file must not be cut as well! No tricks! :-D
[00:58] <llogan> i was just pointing out that you may not need to re-encode regardless of any desire that you may or may not want to reduce the size.
[00:59] <luc4> llogan: you mean there is a way to compress by the same factor without re-encoding and changing the profile? Can you point me to some documentation? I'm not an h264 expert.
[01:01] <llogan> i see that the communication today has not worked as I expected.
[01:03] <mark4o> 100000000x compression without re-encoding: (a) upload to internet (b) replace file with url
[03:05] <Keshl> I have a selecton of frames, starting from dsc_0141.jpg and ending at dsc_0176.jpg. How do I Use this with ffmpeg without renaming them as an image sequence, oÉo?
[03:11] <ppw> http://trac.ffmpeg.org/wiki/Create%20a%20video%20slideshow%20from%20images
[03:11] <mark4o> Keshl: ffmpeg -start_number 141 -i dsc_%04d.jpg ...
[03:14] <Keshl> Danks ^É^
[03:14] Action: Keshl huggles on -É-
[03:16] <Keshl> And what's the "keep aspect ratio" thing when I'm scaling video, oÉo? Used to be -1 but not anymore .É.
[03:16] <mark4o> -1 should still work
[03:17] <Keshl> It reads it as a paramater and says it's not a recognized argument xwx
[03:18] <Keshl> http://www.pasteall.org/44859 oÉo
[03:20] <mark4o> Keshl: -vf scale=-1:1080
[03:21] <Keshl> Danks -É- -Paws at.-
[06:46] <Fieldy> hello, what would be a decent format to record to quickly for screen capture? then I could go and re-encode it after the fact to something else. i'm trying to avoid frame drops and what not.
[06:46] <Fieldy> i have a lot of disk space, so big 1st stage files is fine
[09:51] <Aiena> can someone help me to fix this script see http://pastebin.com/uedmy3qP
[09:51] <Aiena> the issues are posted on the paste
[10:58] <Keshl> WHATDIDIDOO_O?
[10:59] Action: Keshl has red text that appears to be hexes scrolling wildly out of control! D:
[11:02] Action: Keshl got it to calm down by hitting 'H' but now he still has green text D:
[11:03] <Keshl> And hittin' it more just loops between "A different kinda green text" and "that scary red text" D:
[11:26] <Keshl> Kay, new question. If I pass an audio file and video file to ffmpeg, how do I tell it to stop endocing whenever one ends? oÉo?
[11:26] <Keshl> *encoding
[11:27] <sacarasc> -shortest
[11:27] <sacarasc> IIRC.
[11:28] <Keshl> Tried that, got it now. -shortest has to come directly after the last input or weird stuff happens xwx
[11:30] Action: Keshl snugpurrs sacarasc anyway -É-
[12:29] <Keshl> Know what'd be great?
[12:30] <Keshl> If there was a video codec that'd intelligently detect noise in an image that's changing because it's in a shadow, and then not try to replicate it.
[12:30] <Keshl> Just go "Okay, we're using this one frame, not enough in this large, dark area changed, let's just keep it the same".
[14:02] <braincracker> hi
[14:07] <braincracker> "mplayer"s compilation fails with this: libx264.c:(.text+0x14e): undefined reference to `x264_picture_init'  what is the solution?  (ffplay works fine, though does not play sound now, also i have 2 soundcards)
[14:39] <relaxed> braincracker: --> #mplayer
[14:39] <braincracker> thanks, found it already, and flooded them with problems
[15:31] <_d0t> hi. I'm using ffmpeg with my custom encoder to stream h264 video via rtp. I have a problem with pps and sps - those are streamed only at the begining. Is there any way to force pps/sps output per every gop?
[16:26] <Digidog> Hello :-) Hope you all are ok? Greetings from Berlin and best regrards to the ffmpeg community. A question regarding your online compilaton guide:
[16:26] <Digidog> Following the compilation/install guide from http://ffmpeg.org/trac/ffmpeg/wiki/UbuntuCompilationGuide can cause trouble, likely caused by the use of the $HOME variable int he HOWTO. Not sure yet. After complition of the HOWTO and testing it with the version command the result looks fine, but ONLY for ONE TIME. After reopening terminal and typing ffmpeg, it says ffmpeg is not installed.
[16:28] <Digidog> Following the guide installs ffmpeg in the user folder/bin while most apps are installed into /usr/bin. I am not sure, but after trying it 3 times I still have no luck getting ffmpeg compiled and installed on ubuntu 12.10 with this guide. Even if it seems all fine for one second after installation
[16:30] <Digidog> What I ask myself is: Is it caused by my $HOME variabel which points to the ~userfolder or do I miss something whiel installation? It also was need to use some of the terminal commands with sudo to make them work
[16:30] <Digidog> ups, typo *variable, *while
[16:33] <Digidog> Does anyone had same experiences and give me a little hint where I have to look for any modifikation. It seems my envoriment blocks some suggested settings from the HOWTO. All compilation was ok, but terminal doesnt find ffmpeg
[16:44] <cbsrobot> Digidog: maybe ffmpeg is not in your $PATH environment variable
[16:44] <cbsrobot> read https://help.ubuntu.com/community/EnvironmentVariables
[16:52] <Digidog> cbsrobot: thanks for pointing me in the right direction! I will check thru this link! Thank you very much.
[17:02] <bunniefoofoo> I am trying to get a slimmer set of libav binaries with only codecs etc that I need, I am getting undefined reference to av_register_all. I used --disable-everything, then --enabled the stuff I think I need (that seemed obvious) I think there is something not obvious that I have missed, any ideas?
[17:10] <bunniefoofoo> n/m I figured it out, needed --disable-avfilter
[17:42] <Mista_D> is there formula describing a restriction on AAC encoder bitrate in relation of sample rate? Google's mum... ISO 13818-7 has no math for min bitrate.
[17:49] <bunniefoofoo> mista_D just wondering, in theory why would there be a restriction? and wouldn't also have to consider the number of channels?
[17:53] <cryos> Hi, I am a VTK developer, and was hoping someone might help me track down the format where CodecID was renamed to AVCodecID
[17:53] <cryos> I found http://ffmpeg.org/pipermail/ffmpeg-cvslog/2012-August/053381.html that shows the commit, is there an easy way to track that to a release/ABI change?
[17:55] Action: cryos will be out for lunch in about 5, but I will check back later if anyone has ideas/clues. This is related to the FFMPEG API changes, and where they might be documented.
[17:57] <cryos> By format, I meant to say version (need more coffee), ideally with a change in some preprocessor variable I can add an #ifdef for
[18:16] <Mista_D> bunniefoofoo: yes channles too. The faac won't encode 44.1 stereo at 32 kbps. I think its a quality isse than Nero locked down too as 32 kbos 48kHz stereo sounds nasty (:
[19:48] <Fjorgynn> can I sleep?
[22:59] <elkng> I can convert avi to png images with: 'ffmpeg 1.avi -c:v png "%d.png"', is there an option to make it extract not all frames but only evey 50th frame ? so from 10000 frame video it will extract 200 frames ?
[23:01] <elkng> was reconnecting
[23:01] <elkng> I can convert avi to png images with: 'ffmpeg 1.avi -c:v png "%d.png"', is there an option to make it extract not all frames but only evey 50th frame ? so from 10000 frame video it will extract 200 frames ?
[23:01] <llogan> elkng: try the select video filter
[23:01] <llogan> http://ffmpeg.org/ffmpeg-filters.html#select_002c-aselect
[23:03] <llogan> "select=not(mod(n\,50)),setpts=N/((30000/1001)*TB)"
[23:03] <llogan> or something like that
[23:03] <elkng> "select=50" ?
[23:04] <llogan> no
[23:04] <llogan> keep the select part as is. it's the setpts that you may have to change
[23:05] <llogan> so if your input is PAL video, or 25 frames per second, then replace (30000/1001) with 25
[23:06] <llogan> and if you just want 200 frames, then add -vframes 200 as an output option. probably a way to do that with select instead if you prefer.
[23:09] <llogan> ffmpeg -i 1.avi -c:v png -vf "select=not(mod(n\,50)),setpts=N/((30000/1001)*TB)" -vframes 200 monkey-smells-finger-then-falls-out-of-tree_%04d.png
[23:09] <llogan> -c:v png is probably superfluous
[23:09] <llogan> i mean it is superfluous
[23:14] <llogan> elkng: did it work?
[23:18] <elkng> haven't tryed it yet
[00:00] --- Sat Aug 17 2013