[Ffmpeg-devel-irc] ffmpeg.log.20141124

burek burek021 at gmail.com
Tue Nov 25 02:05:01 CET 2014


[00:01] <feliwir> ty c_14 that worked
[00:23] <Popara> Using AVStream.codec.time_base as a timebase hint to the muxer is deprecated. Set AVStream.time_base instead.
[00:23] <Popara> what is this when i use the -f segment
[00:23] <Popara> how can i fix it?
[00:24] <c_14> Ignore it.
[00:24] <c_14> Or try a recent git build.
[00:24] <c_14> Might have been fixed.
[00:24] <c_14> Can't remember.
[00:24] <c_14> Nothing important.
[00:24] <Popara> Well i see some different in the stream output when i use -f mpegts and when i use -f segment
[00:24] <Popara> thought it will be this
[00:25] <Popara> difference*
[00:25] <c_14> And a description of said "difference"
[00:28] <Kip> c_14, so is that a current limitation of the ffmpeg bluray protocol that it requires index file, backup, etc. and it cannot solely use the BDMV folder?
[00:29] <c_14> Kip: it looks to be a libbluray limitation.
[00:29] <c_14> At least from what I can see.
[00:42] <compstomp> Hey guys, has anyone tried statically compiling ffmpeg with ffplay? Are including STL and any other libs specific to ffplay too much of an obstacle? Thanks.
[01:23] <hotwings> can ffmpeg join 2 .h264 files into 1 single stream? both files were encoded with identical settings, resolution, etc..
[01:24] <pentanol> hotwings yes, by using concan
[01:31] <BtbN> you should be able to just concat the actual files if it's raw bitstream, but not sure if there is any container around it
[01:32] <hotwings> ok thanks, ill give that a shot
[07:45] <vibhavsinha> after upgrading my ubuntu, ffmpeg started saying "ffmpeg: error while loading shared libraries: libass.so.4" . How to make ffmpeg use the new libass.so.5 ?
[07:48] <JEEBsv> vibhavsinha: abi change; you will need to recompile
[07:49] <pentanol> vibhavsinha ln -s is not helps?
[07:52] <vibhavsinha_> JEEBsv: cool. doing it right away. thanks
[10:01] <pagios> does ffmpeg use librtmp?
[10:04] <__jack___> it can
[10:05] <__jack___> see the configure --help :   --enable-librtmp         enable RTMP[E] support via librtmp [no]
[10:08] <pagios> __jack___: by default it usees it to output rtmp?
[10:10] <__jack___> seems to no ([no])
[10:25] <Renari> Does anyone know what is wrong with these commands? https://gist.githubusercontent.com/Renari/2c2e819ba0da0c9876aa/raw/cd65a4f2ce6cb88a81f4f7dd2f5feb2ea7d60cb3/gistfile1.txt
[10:26] <Renari> It's saying "Write error occurred on file "<anonymous pipe>": The pipe has been ended.
[10:26] <Renari> This is while trying to use ffmpeg as an external encoder in virtualdub.
[12:13] <rflmota> hi everyone
[12:26] <user1> Hi, i´m new to ffmpeg and also ffserver, i´ve created a ffmpeg syntax to include several 3 audio inputs to 1 video (was made via map) . If you like, i can show you the code . We stremed it and it was working, but our provider has several issues so we try to use it with ffserver and do it by our self, unfortunately , i can´t find a example for a con
[12:26] <user1> fig file with several audio, could someone please help?
[14:58] <cyphase> when i run ffprobe on an mp3 i encoded from some wavs, i get a non-zero 'start'; as in the following string: "Duration: 02:01:02.88, start: 0.025056, bitrate: 64 kb/s". why would it not be 0.000000, what are the effects of that, and how can i fix it?
[15:02] <Mavrik> cyphase, probaby audio timestamps don't start at 0 so that's why you get that unmber
[15:02] <Mavrik> effects? probably none
[15:02] <Mavrik> fix it? I don't think you have to, but reencode should fix that
[15:10] <cyphase> well, reencode just results in it happening again
[15:11] <cyphase> Mavrik, also, i'm trying to encode a 11025hz 16k mp3 as cbr, but it's coming out vbr. any thoughts?
[15:11] <cyphase> the same command with different sample and bit rates are cbr
[15:12] <Mavrik> probaby the encoder can't handle such a strange setting
[15:12] <Mavrik> 16k is... awfully low for mp3
[15:12] <cyphase> yea, i know. it's mono at least
[15:13] <cyphase> it's a low-bandwith archive for a radio show
[15:15] <Mavrik> at those settings, HE-AACv2 will probably be miles better and more supported :/
[15:15] <Mavrik> which mp3 encoder are you using? LAME?
[15:16] <cyphase> yes, libmp3lame, but i have no preference if there's better
[15:18] <cyphase> Mavrik, i may end up getting them to switch to AAC, but for now it's mp3
[15:28] <Joergi> Hi guys!
[15:29] <Joergi> I have two mp4 files and both play fine: Sound and video are ok.
[15:29] <Joergi> Now I want to concatenate them using this command:
[15:30] <Joergi> ffmpeg.exe -f concat -i text.txt -c copy output.mp4
[15:31] <Joergi> In the resulting file, the part, which came from the second mp4 file, does no longer show the video.
[15:31] <Joergi> Instead, I see a black screen with some green blocks, which are moving somehow strangly over the screen.
[15:31] <Joergi> Thesound is still working correctly during this problem.
[15:32] <Joergi> I have tried several different places, at which I did the cut and the problem happened at all of them.
[15:32] <Mavrik> well
[15:32] <Joergi> What can I do to get a working result?
[15:32] <Mavrik> are your videos EXACTLY the same encoding wise_
[15:32] <Mavrik> ?
[15:32] <Mavrik> use same SPS/PSS, same parameters, etc.?
[15:32] <Joergi> Yes. I have recorded them with the same source,same settings, all should be identical:
[15:33] <Joergi> Recorded with Windows Media Center (gives a wtv file), converted that to mp4 with ffmpeg, both times with the same settings...
[15:34] <Mavrik> hrmpf, alot of players very much don't like spliced video
[15:34] <Mavrik> especially MP4 one because MP4 wasn't really designed for that (also, segments support is very hit-and-miss)
[15:35] <Joergi> The direct output file (wtv) basically contains mpeg2 video. Would it work better, if I tried concatenating that and _then_ converting to mp4?
[15:36] <Mavrik> Joergi, doing it all in one step with video filter will be by far the best solution
[15:37] <Joergi> Do you have an example command?
[15:37] <Joergi> I have already tried quite a few things and what I do here has always worked best...
[15:38] <Joergi> What I have done til now is this:
[15:38] <Joergi> ffmpeg -i 1.wtv 1.mp4
[15:38] <Joergi> ffmpeg -i 2.wtv 2.mp4
[15:39] <Joergi> Created a text file with both names in it (I can't pipe cause I'm on Windows) and then
[15:39] <Joergi> ffmpeg.exe -f concat -i text.txt -c copy output.mp4
[15:49] <Joergi> I know checked the files again...
[15:50] <Joergi> and it seems like they DO have one difference:
[15:50] <Joergi> The Sample Aspect Ratio is different:
[15:50] <Joergi> In the one file it is 16:11 while in the other it is 64:45.
[15:50] <Joergi> Can that be a reason for my problem?
[15:51] <rflmota> hi everyone
[15:51] <rflmota> can anyone tell me how to get ffmpeg running 24/7 for streaming? does it have any memory concern?
[16:09] <nasojlsu> you should have a look into OBE
[16:10] <nasojlsu> open broadcast encoder
[16:18] <Fayne> Hi everyone, i've a got a mp3 file with some metadatas, i'm able to see them with audacity, but if i try to check them with ffmpeg as : ffmpeg.exe -i" my.input.mp3", it just gave to me a few metadatas, in example : my metadata "Comment" is missing, have you got an idea to help ? where should i search ? thanks in advance
[16:19] <Fayne> (if i missed something, feel free to tell me, i'm french and i guess my english is pretty poor ^^')
[16:19] <radoslav> hey all :) here is one good for you: http://pastebin.com/rSEZy9cB - although it seems valid this causes a single core CPU to go nuts
[16:21] <radoslav> actually no matter what i set - even the simplest video from a single image causes enormous CPU load
[16:42] <Joergi> I want to change the Sample Aspect Ratio of a video, but _keep_ the Display Aspect Ratio. How can I do that?
[16:50] <c_14> use the setsar filter
[16:56] <Fayne> is ffmpeg able to manage ID3v1 tag please ?
[17:01] <c_14> it should, iirc
[17:01] <c_14> Try ffprobe and various -show_streams or something
[17:01] <relaxed> also, ffmpeg -h muxer=mp3
[17:04] <Joergi> c_14: I tried, but as noted at https://www.ffmpeg.org/ffmpeg-filters.html#toc-Examples-24 that also changes the DAR value and I want that value to stay!
[17:05] <relaxed> Joergi: try setting both setsar and setdar
[17:06] <Joergi> For example?
[17:06] <Fayne> ok so another question ^^, how could you explain that ffmpeg is not able to find me all metatags stored in mp3 ^^ ? thanks :)
[17:07] <c_14> Joergi: you can also use a scale filter with iw*SAR:ih or somethnig along those lines. Can't remember the exact math.
[17:07] <Fayne> could it be caused by differents ID3 versions ?
[17:13] <Joergi> c_14: Setting -vf setdar=16:9 -vf setsar=16:11 does not work. It always changes _both_ values.
[17:13] <Joergi> With other words: It does not take the first of the two settings into acount.
[17:13] <c_14> That's because it's ignoring the first -vf
[17:14] <c_14> -vf setsar=16:11,setdar=16:9
[17:15] <Joergi> Also does not work; same result as with my two -vf commands.
[17:15] <Joergi> Yours changes the DAR to 20:11
[17:17] <c_14> What resolution is your video?
[17:17] <Joergi> 704x576 pixel
[17:23] <c_14> The setdar filter should set the correct sar for that automatically. what does setdar=16:9 give you as a sar?
[17:24] <Joergi> 64/45. This is the old and incorrect SAR of the video
[17:30] <c_14> Hmm, that should only give you a dar of 1.73827 not 1.77778
[17:34] <Joergi> c_14: http://pastebin.com/qL47qLcx
[17:35] <c_14> use just -vf setdar=16/9
[17:36] <c_14> I'm pretty sure you're not supposed to use a colon there...
[17:37] <c_14> If that doesn't work try -vf setdar=dar=16/9
[17:38] <pmarty> It seems to me that ffplay's 's' command (framestep) is incompatible with -skip_frame nokey option, am I right?
[17:41] <Joergi> Both give the same result, SAR stays at the incorrect 64:45.
[17:42] <pmarty> Joergi: you're using it with stream copy?
[17:44] <Joergi> pmarty: I am using it like so: ffmpeg.exe -i 2.mp4 -acodec copy -vf setdar=dar=16/9 2neu.mp4
[17:45] <kepstin-laptop> hmm, that's a 720x576 frame; PAL video?
[17:45] <pmarty> try using different output container (mkv)
[17:45] <kepstin-laptop> if so, in order to get an exact 16:9 display, you have to crop to 704:576 first.
[17:45] <kepstin-laptop> because of video standard sillyness :/
[17:47] <pmarty> ffmpeg.exe -i 2.mp4 -c copy 2neu.mkv
[17:47] <Joergi> How would I dI that?
[17:47] <Joergi> Di => do that?
[17:47] <kepstin-laptop> Joergi: if you just want the correct sample aspect ratio, just do -vf setsar=16/11
[17:47] <kepstin-laptop> the display aspect ratio won't be exactly 16:9, but the video will  be correct.
[17:48] <pmarty> ffmpeg.exe -i 2.mp4 -c copy -vf setdar=dar=16/9 2neu.mkv
[17:48] <pmarty> try this
[17:49] <kepstin-laptop> https://en.wikipedia.org/wiki/Standard-definition_television#Pixel_aspect_ratio has a convenient list of the pixel aspect ratios (SAR in ffmpeg parlance) for the various PAL formats.
[17:49] <Joergi> pmarty: Filtering and streamcopy cannot be used together.
[17:50] <Joergi> That is all it says
[17:51] <Joergi> Running
[17:51] <Joergi> ffmpeg.exe -i 2.mp4 -vf setdar=dar=16/9 2neu.mkv
[17:52] <Joergi> changes nothing - SAR stays at 64:45.
[17:52] <Joergi> Am I right that changing SAR while keeping DAR is impossible?
[17:53] <pmarty> dar = w/h x sar
[17:54] <pmarty> so, yes they're connected
[17:56] <pmarty> Joergi: there is certainly a way of changing dar with stream copy at the container level (not -vf)
[17:56] <pmarty> I remember doing this
[17:57] <blippyp> pmarty: iirc - I also remember doing this...
[17:57] <pmarty> Joergi: -aspect 16:9 option
[17:57] <pmarty> it will work for matroska, possibly others
[17:57] <blippyp> that's probably it
[18:29] <Joergi> pmarty, blippyp: My PC just had to crash
[18:29] <Joergi> Did you write anything after "Joergi: -aspect 16:9 option"
[18:30] <Joergi> ?
[18:30] <pmarty> nope, have you tried using it?
[18:31] <Joergi> Will do. The complete command would then be...?
[18:33] <Joergi> I tried ffmpeg -i 2.mp4 -vcodec copy -acodec copy -aspect 16:9 output.mp4
[18:33] <Joergi> => SAR incorrect.
[18:34] <Joergi> You said that SAR and DAR would be connected like this:
[18:34] <Joergi> dar = w/h x sar
[18:35] <Joergi> How can I then, with the same width, height and DAR, have two different SAR values?
[18:53] <Joergi> ARGH!!!
[18:53] <Joergi> Need something to bang my head against...afk
[18:53] <Joergi> *bang*
[18:54] <Joergi> *bang bang*
[18:54] <Joergi> Some simple math shows what the problem was:
[18:54] <Joergi> Although I used the same device with the same settings, the same programme and the same commands to modify the files...
[18:54] <Joergi> ...
[18:55] <Joergi> they had A DIFFERENT RESOLUTION
[18:55] <Joergi> I cannot say why this is the case, but fact is the resolution is different.
[19:54] <gabriel> Hello all,
[19:54] <gabriel> I'm trying to create mpeg videos containing just 2 images, but I have many pairs that I need to do this to. Very few if any have sequential names, and it would be so much easier for automating if I could specify the input filenames for the ffmpeg command without relying on the image%01d.png type syntax. Is there some known way to cherry-pick images for a movie sequence in ffmpeg? Am I missing something in the docs? Thanks so much for any help you guys can
[19:54] <gabriel> provide.
[19:55] <gabriel> Something like: ffmpeg -f image2 -i '12-small.png' -i '921-small.png' -vcodec mpeg4 -b:v 800k -r 24 -y output.mov
[19:57] <kepstin-laptop> gabriel: maybe something like ffmpeg -i 'first-image.png' -i 'second-image.png' -filter_complex 'concat=n=2:v=1:a=0' -vcodec mpeg4 -b:v 800k -r 24 -y output.mov
[19:57] <gabriel> Let me try that
[19:58] Action: kepstin-laptop wonders why you want a 2-frame 1/12 of a second long video, but whatever.
[19:59] <gabriel> Im trying to use the mpeg encoder to compare how simillar two images are. So something like (mpegSize(x, y) + mpegSize(y, x))/(mpegSize(x,x) + mpegSize(y,y) -1)
[20:00] <gabriel> That worked! Thanks so much
[20:00] <kepstin-laptop> that's got to be the craziest idea i've ever heard of.
[20:00] <gabriel> Hahaha crazy like a fox?
[20:00] <kepstin-laptop> but sure, I suppose it would work
[20:01] <gabriel> I got it from here: http://www.cs.ucr.edu/~eamonn/SDM_insects.pdf
[20:41] <gabriel> Is there a way to make ffmpeg output the resulting fielsize in Bytes instead of KB?
[23:21] <TSM> I am trying to track down a problem with MP4 encoded with the latest ffmpeg, they play fine on my desktop browsers but not properly on BB10 or Andoid 5
[23:22] <TSM> if i encode them with qtfaststart flag then it wont work at all, otherwise they play for a few seconds and then stop
[23:22] <TSM> its weird and cant find why it would happen
[23:51] <TSM> http://pastebin.com/DPWztTur
[23:53] <pmarty> I'm extracting part of .wmv file like this: ffmpeg -i in.wmv -ss 1500 -c copy out.mkv . But then the pts of the first frame of out.mkv is at 1.7 sec (first frame of audio is at 0.03 sec). ffplay plays a first few frames in slow motion (A-V is negative). It hinders -f concat also. Why everything cannot simply start at 0?
[23:53] <pmarty> I checked pts with (a)showinfo filter
[23:56] <llogan> TSM: has it worked with a previous ffmpeg?
[23:59] <TSM> llogan, no, i was running a version from back in feb previously
[00:00] --- Tue Nov 25 2014


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