[Ffmpeg-devel-irc] ffmpeg.log.20140926

[burek]

[01:55] <kryo_> hey, do i have to re-encode video to use the -g option?
[01:55] <kryo_> i'm currently using it with -vcodec copy
[01:57] <kryo_> apparently it's doing nothing
[01:59] <sacarasc> Yes, you do.
[01:59] <sacarasc> It changes frames.
[02:00] <kryo_> damn
[02:00] <kryo_> don't really want to re-encode
[03:03] <MikeJoel> I am still having trouble with converting an swf to mp4. It converts but instead of the whole swf being seen it appears to be enlarging the top left corner of the swf to fill the screen for the mp4... here is what I get when I run ffmpeg http://www.parksandsonspiano.com/Testsite/ffmpeg.html
[03:03] <MikeJoel> (the above address is the command prompt output not the video)
[03:04] <llogan> Input stream #0:0 frame changed from size:400x400 fmt:yuvj420p to size:195x181 fmt:yuvj420p
[03:05] <MikeJoel> huh.. I also tried it by telling it 400x400 still made no difference
[03:07] <MikeJoel> any idea how to prevent that?
[03:11] <MikeJoel> I just remain the flash to be sure nothing in the video was doing it... still same problem.
[03:11] <relaxed> remain?
[03:11] <MikeJoel> remade - sorry
[03:11] <relaxed> put the swf up somewhere
[03:13] <MikeJoel> http://www.parksandsonspiano.com/Testsite/intro.swf
[03:15] <relaxed> the first few frames are 400x400 and then it switches the frame size to 195x181 as llogan pointed out
[03:18] <MikeJoel> I ffprobe the swf and it says 400x400. When I watch it, it stays 400x400 all the way through
[03:20] <relaxed> but it does not. if you have the images and audio and it shouldn't be too hard to create it using ffmpeg
[03:21] <MikeJoel> yeah - I was going to switch to that if I couldn't do it...
[03:21] <MikeJoel> I am slowing the video down to see each frame
[03:21] <relaxed> https://trac.ffmpeg.org/wiki/Create%20a%20video%20slideshow%20from%20images
[03:23] <MikeJoel> I just saw it... it looks like it shrinks down to a block in the middle of the screen.
[03:23] <MikeJoel> grr
[07:08] <kaotiko> hi
[07:22] <relaxed> hi
[09:50] <wintershade> hi everyone
[10:05] <EvolE> hello
[10:17] <wintershade> a quick question about libx264 here. I'm doing a ffmpeg -i <input> -c:v libx264 -preset slow -crf 21 -c:a libfdk_aac -vbr 5 <output.mkv> and getting less than 4 FPS on average. is this normal?
[10:18] <wintershade> my CPU is an old Intel core2duo, but I remember having higher framerates in the past with the same input video format (DVD VOB, 720x576)
[10:18] <wintershade> tia
[10:22] <Mavrik> wintershade, yes, that is normal for "slow" preset :)
[10:22] <Mavrik> with medium preset you get like 20-40 fps on a modern quad processor
[10:24] <wintershade> Mavrik: oh... hmm ok. so how good would it be performance-wise to get an 8-core i7 CPU?
[10:24] <wintershade> I'm getting 11 FPS on medium :-/
[10:24] <Mavrik> A proper 600$ Xeon 8-core?
[10:24] <Mavrik> or the fake 4-core + hyperthreading i7?
[10:24] <flarunt> i think the settings within the presets change over time, so preset slow is probably more cpu intensive now than it was in the past
[10:24] <Mavrik> mhm
[10:24] <Mavrik> we run medium or faster for real-time encodes mostly
[10:25] <wintershade> Mavrik: I don't believe I could get a laptop with a proper 8-core Xeon, at least not with my budget (or, well, at least not until I write a bestseller).
[10:26] <wintershade> so, I should just be patient and wait a few days if I want to encode on slow?
[10:27] <wintershade> actually, I'm interested about both. anyone got any info on 8-core and fake 4-core+HTs? what would the framerates be?
[10:27] <Mavrik> well, yes
[10:27] <Mavrik> or just don't use slow :)
[10:27] <Mavrik> as I said, I'm getting like 15-30 fps on my i5 2500k
[10:28] <wintershade> Mavrik: not using slow is kinda pointless... my VOB source is at around 6-7 mbps bitrate, and the medium with -crf 20 gives it a... 6,5 mbps
[10:28] <wintershade> lol
[10:29] <flarunt> increase the crf then
[10:29] <wintershade> flarunt: wouldn't that degrade video quality?
[10:31] <flarunt> of course but if your h264 encode has the same bitrate as mpeg2 source then clearly something is wrong. the bitrate should be a third or less.
[10:32] <Mavrik> mhm :)
[10:38] <wintershade> flarunt: okay, got any ideas on what might be wrong?
[10:42] <wintershade> my current line is ffmpeg -i <input> -c:v libx264 -preset medium -crf 21 -c:a libfdk_aac -vbr 5 -cutoff 20000 -threads 8 test.mkv
[10:51] <Mavrik> what do you mean wrong?
[10:54] <wintershade> well, flarunt said that something is wrong since I am getting bitrates very similar to the DVD source.
[10:55] <flarunt> use a higher crf to force the bitrate down and then check the output
[10:56] <reactormonk> How do I capture audio output from another program with ffmpeg via pulse?
[10:57] <wintershade> flarunt: well okay, I'll try that. although I'm not the biggest fan of such things. I'll check on other video sources, it might be that the bitrate is going crazy due to a noisy/grainy source.
[10:58] <flarunt> it could also explain why you are getting a lower fps than you expected
[10:59] <wintershade> it does?
[10:59] <wintershade> wow. didn't know that one :-/
[10:59] <wintershade> but it... kinda makes sense.
[11:00] <wintershade> but as Mavrik says, my FPS is normal for my CPU and the preset...
[11:00] <wintershade> okay, yeah. the video is a bit grainy. using hqdn3d lowers the bitrate down by half.
[11:01] <flarunt> when the complexity of the video increases i often see the fps drop, then rise again when not much is happening on screen
[11:01] <wintershade> another question. how much does the CPU clock vs. number of cores affect the encoding speed?
[11:01] <wintershade> i.e. would it be more worth it to get a 4-core 4GHz CPU or a (true) 8-core 2.4 GHz CPU?
[11:01] <wintershade> if anyone has any idea on that...
[11:02] <flarunt> it scales pretty linearly i think
[11:02] <wintershade> so they'd probably do the same?
[11:02] <flarunt> multiply clockspeed by number of cores. bear in mind that each new generation of intel cpus is roughly 10% faster at the same clock speed.
[11:03] <wintershade> ok. also... if I may ask. a 4-core Intel or a 4-core AMD? experiences?
[11:03] <wintershade> I haven't worked with AMD for a decade now, so I have no idea whatsoever how good they are.
[11:03] <flarunt> intel
[11:03] <wintershade> ...I thought as much.
[11:04] <wintershade> I know Intel rocks with DMBS, but video encoding/processing is something I actually know very very little about.
[11:04] <Mavrik> Intel is lightyears ahead, especially for x264
[11:05] <wintershade> cool. I'm asking because I heard some people swear their lives and sould on AMD, but those people are mostly gamers so I reckon it's hardly comparable.
[11:05] <flarunt> i have a 2600k and a fx8350. i regret buying the fx8350.
[11:05] <wintershade> flarunt: why?
[11:06] <flarunt> slow than an i5/i7 and much more power hungry
[11:06] <wintershade> okay, two more questions hardware-wise.
[11:06] <wintershade> first, I have an NVIDIA graphics card. can I use it to speed up my encoding? or is x264 doing it already?
[11:06] <Mavrik> no
[11:06] <wintershade> Mavrik: no for latter, or for both?
[11:07] <Mavrik> x264 has some limited support but it'll trash your quality
[11:07] <Mavrik> GPUs aren't really good for quality encodes
[11:07] <wintershade> Mavrik: gotcha. so I should disable the opencl extensions?
[11:07] <Mavrik> I didn't notice any difference either way
[11:08] <flarunt> http://mewiki.project357.com/wiki/X264_Settings#opencl
[11:09] <wintershade> flarunt: ok thanks for that bit of info. much appreciated!
[11:09] <wintershade> second question. I'm currently constructing a Gentoo-based cluster from three old PCs laying around back home. they would run a 32-bit OS, since two out of three PCs are 32-bit. the average speed of each CPU is 2GHz. would that be any good for x264? Does x264 even support cluster-based processing?
[11:10] <wintershade> (I'm asking because I've googled around for this a bit, but didn't find anyhting official/useful)
[11:11] <flarunt> http://forum.doom9.org/showthread.php?t=127611
[11:11] <flarunt> not sure if that is 2pass or crf
[11:12] <wintershade> hmm. this sounds good!
[11:12] <wintershade> I hope I could get something like that for Linux, though...
[11:13] <wintershade> okay, I have to run now. thanks everyone for your help! this was very useful. cheerio~
[11:14] <Mavrik> wintershade, I would advise against it
[11:14] <Mavrik> you'll get bad quality if you try to slice up your videos for pretty much no gain
[11:14] <Mavrik> either use the machines to each encode their own video or just throw them into a trash bin and get a single powerful encoder... way cheaper (due to power use difference) in the long run
[12:47] <timothy> hi, I have a little problem with new ffmpeg (2.4.1)
[12:49] <timothy> ok
[12:50] <timothy> http://pastie.org/pastes/9596524/text?key=pkmzeb8mt82ahzpfqwmg7a
[12:51] <timothy> the error is: "Error while filtering." with 2.3.x it used to work
[12:56] <timothy> sacarasc: and enabling debugging / logging does not help
[12:58] <sacarasc> That filter is beyond me, someone might come along who understands, though.
[12:58] <timothy> ok, i can try to find which filter part does not work
[13:00] <relaxed> timothy: it's recommended to use -filter_complex with multiple inputs now
[13:02] <relaxed> https://www.ffmpeg.org/ffmpeg-filters.html#Examples-50
[13:04] <timothy> overlay=10 so 10 is the second input?
[13:05] <relaxed> yes
[13:08] <timothy> '[0:v]scale=iw*min(1920/iw\,1080/ih):ih*min(1920/iw\,1080/ih), pad=1920:1080:(1920-iw*min(1920/iw\,1080/ih))/2:(1080-ih*min(1920/iw\,1080/ih))/2 [scale]; [scale][1:v] overlay=main_w-overlay_w-10:main_h-overlay_h-10 [out]'
[13:08] <timothy> so something like that?
[13:08] <timothy> yes, there is something wrong
[13:11] <timothy> '[0:v]scale=iw*min(1920/iw\,1080/ih):ih*min(1920/iw\,1080/ih), pad=1920:1080:(1920-iw*min(1920/iw\,1080/ih))/2:(1080-ih*min(1920/iw\,1080/ih))/2 [scale]; [scale][1:v] overlay=main_w-overlay_w-10:main_h-overlay_h-10'
[13:11] <timothy> it seems correct now
[13:11] <timothy> thx relaxed
[15:14] <chutchut> hey all
[15:14] <chutchut> is it possible to stream RTSP over SSL?
[16:51] <wintershade> hi everyone
[16:54] <Fjorgynn> hi me
[17:06] <chutchut> hey guys X)
[17:10] <Fjorgynn> :o
[17:16] <chutchut> is it possible to stream RTSP over SSL?
[17:18] <Fjorgynn> maybe
[17:45] <chutchut> know any links/resources Fjorgynn ? X)
[17:50] <mjuszczak> Using a build of ffmpeg 2.4 off of a PPA but it doesn't seem to have qt-faststart.  Is that because it's 2.4 or is that because the PPA didn't enable it?
[17:51] <chutchut> think it comes in a separate (utils) package mjuszczak
[17:52] <chutchut> alternatively there is https://github.com/danielgtaylor/qtfaststart which is a python version mjuszczak
[17:53] <mjuszczak> oh, thank you!
[17:54] <chutchut> apt-get install libav-tools (un ubuntu) i believe for the C version mjuszczak
[17:54] <mjuszczak> thanks!
[17:55] <timothy> qt-faststart does not work with mp4, right?
[17:55] <sacarasc> mjuszczak: It's not needed any more.
[17:55] <mjuszczak> sacarasc: what do you mean?
[17:55] <chutchut> think it does timothy? why not sacarasc ?
[17:56] <sacarasc> ffmpeg -i blah -movflags faststart blah.mp4
[17:56] <sacarasc> That will do it.
[17:56] <chutchut> ahh yea its built-in
[17:56] <timothy> also with -vc copy?
[17:56] <timothy> I need it too :P
[17:56] <chutchut> but for screwy files from other sources, qt-faststart is still useful
[17:56] <sacarasc> timothy: It should work, yes.
[17:56] <timothy> ok, thanks
[17:57] <sacarasc> Also, chutchut, getting people to install a fork of something in the original channel is fun!
[17:57] Action: sacarasc disappears into the ether.
[17:58] <chutchut> lol sorry sacarasc, wasnt 'getting' anyone to do anything though.. Purely useful advice X)
[17:58] <chutchut> not good to be blind or narrow-minded eh X)
[17:59] <chutchut> again, sorry for being informative, my bad X
[18:27] <quebre> does any of you know how can i encode my .avi movie to MPEG-1 ? so then i can record movie on CD and play it on my DVD player...
[18:33] <Mavrik> MPEG-1? O.o
[18:34] <Mavrik> quebre, shouldn't ffmpeg -i <file>.avi -target ntsc-dvd -q:a 0 -q:v 0 output.mpg work?
[18:34] <Mavrik> or film-dvd or pal-dvd?
[18:34] <quebre> but why dvd ?
[18:35] <quebre> i only have CD discs, so trying to create VCD format and then burn it
[18:35] <quebre> but it's magic for me
[18:35] <Mavrik> DVD describes a format
[18:35] <flarunt> it doesnt really matter if you burn the output onto cd or dvd.. your authoring software should be able to make an SVCD which is mpeg2
[18:35] <c_14> use -target vcd
[18:35] <c_14> or pal-vcd or ntsc-vcd
[18:35] <quebre> ok
[18:35] <c_14> You'll still have to author it though.
[18:35] <quebre> pal-vcd i think..
[18:35] <quebre> author ?
[18:36] <flarunt> you cant just put the mpeg on the disc, it has to be burnt in a certain way
[18:36] <quebre> oh, hmm can you recommend me some software that can do it ?..
[18:37] <c_14> Have never used any, you can probably just search for vcd authoring software on the internet or vcd in your favorite package manager.
[18:37] <flarunt> i think you can use something like VCDGear to create an image to burn
[18:37] <flarunt> but software like nero etc should be able to do it anyway
[18:38] <quebre> alright !
[18:38] <quebre> thank you
[18:38] <quebre> if i do the -target pal-vcd then ffmpeg will choose MPEG-1 or MPEG-2 ? i readed on site that MPEG-1 is best choice as most dvd players will play it
[18:41] <c_14> mpeg1video
[18:56] <quebre> that did not ended well...
[18:56] <quebre> ffmpeg -i ocean.avi -target pal-svcd ocean.mpeg
[18:56] <quebre> input size is 698MB output is 1.47gb
[18:56] <quebre> that wont fit on CD...
[18:57] <c_14> not svcd, vcd
[18:57] <quebre> hmmm
[18:57] <quebre> but is it not possible to convert to svcd without making the output bigger than input ?
[18:58] <c_14> svcd uses a bitrate of 2040k
[18:59] <c_14> If that is higher than the input bitrate, it will get bigger.
[19:00] <flarunt> a 700mb mpeg4 video has a greater level of compression, so your mpeg1 vcd will be larger and i guess youll have to split it over multiple cds. but really your dvd player should be able to play dvds!
[19:02] <quebre> it is able.. but im out of DVD cds ... :(
[19:03] <quebre> but !
[19:03] <quebre> i just read on front of my DVD player 'MPEG4' supported
[19:03] <quebre> so i can use mpeg-4 for svcd for better compression ?
[19:04] <flarunt> you should be able to just burn a normal data disc with the file on it
[19:04] <flarunt> assuming your .avi is mpeg4
[19:06] <quebre> ffmprobe says it's mpeg4
[19:06] <quebre> ;)
[19:42] <zooptwo> Hello, I am having a problem converting a file to pcm_s16le  It is forcing a metadata of encoder=Lavf54.63.104   This I am sure is normally not a problem, but as I am doing this for a phone system it does nto support this and fails to play the file.
[19:42] <zooptwo> Any Idea what I could do?
[19:43] <c_14> Wait, what.
[19:43] <c_14> The phone reads the Encoder metadata tag and then decides not to play the file?
[19:43] <zooptwo> I is unable to read it and fails.
[19:43] <zooptwo> it thinks that it is not a valid audio file.
[19:43] <zooptwo> This is Asterisk 1.8 by the way.
[19:44] <zooptwo> Sure one minute.
[19:45] <quebre> can i tell ffmpeg to scale any-size video to max 700MB ?
[19:45] <flarunt> quebre: yes but I think you'll have to do a 2-pass encode rather than crf
[19:46] <c_14> use 2-pass cbr with (video bitrate * length) + (audio bitrate * length) < 700mb
[19:46] <quebre> ugh
[19:46] <quebre> how would it look in command line ?...
[19:47] <flarunt> or pick a suitably high crf and hope for the best..
[19:48] <c_14> https://trac.ffmpeg.org/wiki/Encode/MPEG-4
[19:50] <zooptwo> http://pastebin.com/U7FA6kBi
[19:53] <llogan> zooptwo: could you try using ffmpeg code from current git master?
[19:53] <llogan> you can just configure and make, no need to install
[19:54] <zooptwo> I can try
[19:54] <llogan> a bare configure should be fine in this case
[19:54] <zooptwo> FYI this E-mail list thread seemed to try to be doing the same thing.
[19:54] <flarunt> perhaps you need to output to raw pcm instead of wav?
[19:54] <zooptwo> http://ffmpeg.org/pipermail/ffmpeg-user/2011-June/001365.html
[19:55] <flarunt> http://stackoverflow.com/questions/4854513/can-ffmpeg-convert-audio-to-raw-pcm-if-so-how
[20:07] <zooptwo> Because of other limitations not related to asterisk itself. a .wav file is required.
[20:07] <zooptwo> I have tried using a pcm file and even just renameing it to .wav but no love.
[20:11] <flarunt> its a long shot but have a look at RIFFStrip.. http://mark0.net/soft-riffstrip-e.html
[20:11] <llogan> first step is to try with git master
[20:31] <zooptwo> llogan, it would appear that it does the same thing.
[20:32] <zooptwo> This is the right get source right?  git://source.ffmpeg.org/ffmpeg.git
[20:34] <zooptwo> flarunt, Thanks I will look into that. I think that the RIFF is actually important though.  Maybe I am wrong about this meta tag then.
[20:34] <zooptwo> I was just looking for difference in the audio files and that is the only thing I could find different.
[20:34] <zooptwo> I created the audio file first with ffmpeg and asterisk does not like it.  I use sox on the from created from ffmpeg and then it works.
[20:35] <zooptwo> the difference I saw was just the metadata.  So I could be wrong.  It could be something else that is making it unhappy.
[20:35] <llogan> zooptwo: yes, that's the correct repo. thanks for testing.
[20:37] <zooptwo> I need ot get some sleep.  Thanks for the help.
[21:08] <darkfrog> am I supposed to use avconv instead of ffmpeg now?
[21:09] <llogan> darkfrog: you can use whatever you want. we only support ffmpeg from FFmpeg here
[21:10] <darkfrog> llogan: what's the relationship between avconv and ffmpeg?
[21:10] <llogan> avconv is made by a fork of FFmpeg called Libav
[21:11] <darkfrog> llogan: okay...looking for an ffmpeg ppa for Ubuntu 14.04 then...
[21:12] <llogan> https://launchpad.net/~mc3man/+archive/ubuntu/trusty-media
[21:13] <darkfrog> llogan: thanks
[21:15] <darkfrog> I'm writing a web application that needs to be able to do several things: 1.) read video details, 2.) create a screenshot from the video, 3.) transcode the video to h264
[21:15] <darkfrog> I'm assuming ffmpeg is capable of all this via command-line?
[21:17] <llogan> yes
[21:43] <Arlis> hi
[21:47] <kaotiko> hi
[22:03] <Arlis> alio
[22:05] <Arlis> something is here?
[22:05] <Arlis> hi
[22:06] <darkfrog> is there a way to transcode a video and resize to a specific width and height (maintaining aspect ratio) and crop the excess?
[22:06] <Arlis> ok
[22:06] <Arlis> then you can tell me
[22:06] <llogan> darkfrog: see the scale and crop filters
[22:07] <Arlis> why need \bin\ffprobe.exe
[22:07] <llogan> "-vf scale=640:-2" will scale to 640 pixels wide, and -2 will 1) make the height whatever it needs to be to preserve aspect, and 2) will make the height divisible by 2
[22:09] <darkfrog> llogan: what if I have specific dimensions like 240x180 and I want it scale to either width or height and crop the other (centered)?  640:-2 is fine if I know the video is wider than the size I'm scaling too, but that doesn't handle if it's taller.  I suppose I can determine this myself by reading the video details via ffprobe, but was hoping ffmpeg had the ability to do this automatically.
[22:11] <llogan> darkfrog: sorry, but i'm not quite following you. and i have to go now, but I'll be back in an hour or so. someone else may be able to help until then.
[22:12] <darkfrog> llogan: no worries, thanks anyway
[22:14] <darkfrog> The question is, if I have a video that is 500x360 I want the resulting video to be 240x180 and horizontally centered with the extra 10 pixels of width cut off (it should scale it to 250x180 and crop five pixels on the left and right)
[22:15] <darkfrog> similarly, if I have a video that is 480x400 it should scale to 240x200 and crop 10 pixels above and 10 pixels below
[22:22] <Diogo> hi this is the best way to generate multiple ts with different quality http://pastebin.com/iybS6mXn
[22:56] <llogan> Diogo: they are all using the same value for the rate control
[22:58] <Diogo> I lnow
[22:59] <Diogo> But i dont know if this command is efficient or i need to change something
[23:00] <llogan> it is not efficient because you could probably just scale once
[23:01] <llogan> https://trac.ffmpeg.org/wiki/Creating%20multiple%20outputs#Multipleencodingsforsameinput
[23:02] <llogan> unless each output needs to be scaled to a different size.
[23:29] <darkfrog> llogan: did you see my explanation?
[23:30] <llogan> yes, but i didn't understand. you'll just have to read the docs of the scale and crop filters
[23:32] <darkfrog> llogan: man page or is there a better documentation?
[23:33] <llogan> man ffmpeg-filters
[23:34] <darkfrog> I think I can do what I want by a scale then crop filter
[23:35] <darkfrog> I guess I'll have to figure out the values manually
[00:00] --- Sat Sep 27 2014