[Ffmpeg-devel-irc] ffmpeg.log.20130811

burek burek021 at gmail.com
Mon Aug 12 02:05:01 CEST 2013


[00:35] <Borg^Queen> apparently something in the latest ffmpeg broke, mplayer
[00:40] <Borg^Queen> apparently, according to mplayer devs, something in ffmpeg is borked.
[01:09] <_dan_> hi anyone here?
[01:10] <_dan_> i am trying to figure out how to stream my h264 video to browser using html5
[01:10] <_dan_> without keeping it saved in mp4 format on my drive
[01:10] <_dan_> seems like mp4 can't be muxed and streamed in real time?
[01:23] <Borg^Queen> _dan_: hang on for a bit, everyone is working on something. Someone who knows will eventually answer.
[01:24] <Borg^Queen> or at least send you in the right direction.
[02:24] <brad_c6> Hello, After using avformat_open_input on an audio file I am able to get some information about each stream (such as the codec, number of channels). But I attempt to query the codec for the particular stream and the channel_layout is always 0. Am I querying incorrectly? Thank You
[03:20] <grkblood> how do I remove a specific frame number from a video to keep as a picture?
[03:20] <grkblood> i have the frame number I want from avidemux
[03:31] <grepper> dunno how easy it would be to be "frame accurate" but you could get close with -ss POSITION after the -i FILE. (seconds or HH:MM:SS.xxx) Avidemux might make it easier to get the 'exact' frame. Or transcode (transcoding.org). I'm no expert however...
[03:57] <crumb> how do you normalize the volume of channels?
[04:12] <crumb> Unrecognized option 'af'
[04:12] <crumb> what is it now
[04:12] <crumb> i'm trying to do volumedetect
[04:25] <Borg^Queen> gn everyone.
[06:53] <yump> Does anyone have an idea as to what filter to use to reduce the blocking from a source that looks like this? http://i.imgur.com/viiR7e3.png
[06:54] <yump> I see nothing about blocking in the output of ffmpeg -filters
[07:12] <crumb> pirating jackie chan?
[07:16] <yump> mebe :3
[07:26] <yump> The only copy I found was terrible: uncompressed PCM audio track in the first season, bad upscaling in the 2nd and 3rd, and it's all msmpeg4.
[12:08] <t4nk361> ffmpeg+ffserver stability issue via 127.0.0.1 http post
[12:09] <t4nk361> it is not stable about ffmpeg send video to ffserver stability issue via 127.0.0.1 http post
[13:23] <jure> hi
[13:23] <jure> I seem to have an issue with creating a slideshow from images
[13:23] <jure> there are no issues when using matroska as a container format
[13:23] <jure> only when using avi or mp4
[13:24] <jure> the first image is displayed for twice the set time, while the last image is only displayed for a single frame
[13:25] <jure> the command is in this format:
[13:25] <jure> ffmpeg -y -f image 2 -r 0.20 -i %02d.png -i audio.wav -shortest -c:v libx264 -tune stillimage -c:a pcm_s16le -pix_fmt yuv420p -crf 0 -r 30 output.avi
[13:26] <jure> err ... that's "image2", not "image 2"
[13:28] <hans_henrik> can i join images with ffmpeg to procude 1 big png/jpg?
[15:03] <jure> ffmpeg seems to drop either the last or the first batch of frames that should've been duplicated
[15:12] <jure> http://superuser.com/questions/434232/why-is-the-first-image-changing-so-quickly-when-creating-video-from-images-via-f/552718#552718
[16:02] <jure> oh great, using -vf fps=30 now the first image displays correctly, and the last image is displayed for a single frame
[16:31] <heiko_xs> smplayer can't seek correctly in my dvb-s recordings (MPEG-TS), so I tried to convert a recording like this: ffmpeg -i in.ts -vcodec copy -acodec copy out.mpg. this seems to work fine, I see and hear no difference between the two, seeking works too. but out.mpg is smaller than in.ts (5.3GB vs 7GB). where does that size different come from? Stream #0.0 of in.ts is dvb_teletext, can that make such a big difference? "ffmpeg -i in.ts" prints in
[16:31] <heiko_xs> fo about other tv channels, but I have no idea what that is about. info about in.ts http://pastebin.com/SMSaFubK and out.mpg http://pastebin.com/xjcLt5Yk
[16:57] <Mavrik> heiko_xs, teletext and metadata coult be
[17:22] <elkng> my ffmpeg crashes
[17:23] <elkng> why ?
[17:27] <elkng> this is file's parameters: http://sprunge.us/ARBQ and I use that command: ffmpeg  -i "file.flv"  -vcodec mpeg4 -vb 1500k   -ab 128k -ar 4100 -ac 2 -acodec libmp3lame -y -f avi "_/_3/file.avi" to convert it to *.avi, and thats the entire output: http://sprunge.us/DegF, is there something wrong with file ? or its a ffmpeg's problem ?
[17:28] <elkng> as you can see there is buffer overflow or something: "*** glibc detected *** ffmpeg: free(): invalid next size (normal):"
[17:29] <elkng> I got that file from that link http://www.youtube.com/watch?v=rvj_J0YChmE and its called rvj_J0YChmE.flv, if you can download it and try on you ffmpeg you can see if thats a file's issues or not
[17:29] <Fjorgynn> lägg av
[17:29] <elkng> I use "ffmpeg version 1.2 Copyright (c) 2000-2013 the FFmpeg developers"
[17:30] <elkng> its quite fresh, isn't it ?
[17:30] <elkng> seems like topic says there is "FFmpeg 2.0.1" allready, strange why so big leap from 1.2 to 2.0 version, are there really big changes ?
[17:32] <elkng> you know what interesting thing is ? seem like ffmpeg was able to encode that file to avi, and then crashed, because both are 0:15:9 long, so it actually completed encoding and only then crashed for some reason
[17:32] <elkng> so maybe its not an issue, I just skip that file
[17:34] <elkng> I also noticed that line in dmesg: "libavutil.so[20318]: segfault at 24660 ip b77d4412 sp bff5a63c error 4 in libavutil.so.52.18.100[b77cd000+2d000]"
[17:34] <elkng> if it helps
[17:35] <elkng> I already removed that flv file, maybe I should've tryed it with 2.0.1 versio of ffmpeg ?
[17:38] <relaxed> elkng: did you compile this yourself?
[17:39] <elkng> relaxed: I compilled my ffmpeg 1.2 with that script http://sprunge.us/OiVB
[17:41] <relaxed> compile it by hand
[17:41] <elkng> what ?
[17:42] <elkng> what the difference ?
[17:42] <elkng> I made that script, and its the same as to issue those commands in command line but instead they are batched in one file
[17:42] <relaxed> That script sets SLKCFLAGS="-O2 -march=i486 -mtune=i686" which should really be left to ffmpeg's configure.
[17:43] <relaxed> I don't know if that's the issue, but you can quickly check by compiling it by hand to see if you run into the same issue.
[17:46] <elkng> should I remove "SLKCFLAGS="-O2 -march=i486 -mtune=i686" part entirely or what ?
[17:49] <relaxed> remove --arch=$ARCH, CFLAGS="${SLKCFLAGS}", and CXXFLAGS="${SLKCFLAGS}"
[17:51] <relaxed> on older versions there's --enable-runtime-cpudetect
[17:51] <relaxed> which is the default now
[18:01] <JustAnotherUser> I want to record a webcam and see the output as it records to disk. is this possible?
[18:03] <Fjorgynn> linux?
[18:08] <JustAnotherUser> WIndows
[18:08] <JustAnotherUser> using dshow
[18:09] <JustAnotherUser> the command I am using now which works fine for outputting the file, all I want to add is a preview window of what is being seen by the webcam: ffmpeg -y -f dshow -s 640x480 -r 60 -rtbufsize 3000k -i video="PS3Eye Camera" out.mp4
[18:09] <hans_henrik> JustAnotherUser, pretty sure you can use VLC for it tho
[18:10] <JustAnotherUser> How?
[18:10] <hans_henrik> JustAnotherUser, use the convert/save thing of vlc, with the preview option on
[18:11] <JustAnotherUser> how can i get it to record to MP4?
[18:11] <hans_henrik> it asks you when you press the "save/convert" button..
[18:12] <hans_henrik> not sure exactly what to press, but its an easy-to-use gui thing
[18:12] <hans_henrik> should be easy to figure out
[18:12] <hans_henrik> h264  tho, for mp4
[18:13] <hans_henrik> Profile: Video - H.264 + MP3 (MP4)     for example :p
[18:16] <JustAnotherUser> easy to use gui things I don't care abouit... not to mention it crashed.
[18:48] <sam113101> HI GUYS
[18:49] <sam113101> I want to transform mp3 files into videos with a picture on them (static picture, not changing), can I do that with ffmpeg?
[18:51] <jure> yes
[18:51] <sam113101> how?
[18:51] <jure> google create a video slideshow with ffmpeg
[18:51] <jure> it has instructions for single-picture videos as well
[18:52] <jure> I want to create a true slideshow, but it seems ffmpeg is buggy in that regard
[18:52] <jure> https://ffmpeg.org/trac/ffmpeg/ticket/1925
[18:53] <jure> duplicate of https://ffmpeg.org/trac/ffmpeg/ticket/1578
[18:53] <jure> 13 months old :(
[19:11] <sam113101> sucks man
[19:13] <hans_henrik> could som1 try that on youtube? :p
[19:18] <sam113101> my script is working
[21:16] <slick> hi im trying to record minecraft videos without sound and i have the dimensions and position of the window but i need help putting it into one command for ffmpeg
[21:17] <slick> can anyone help me?
[21:20] <jure> http://trac.ffmpeg.org/wiki/How%20to%20grab%20the%20desktop%20(screen)%20with%20FFmpeg
[21:21] <slick> ty
[21:22] <jure> np :)
[21:22] <slick> im gonna try it out right now brb gonna start minecraft up (java game) so yea bbs ill let u know wut happens
[21:31] <slick> bak it did its job but the video output was very fuzzy/blurry kinda
[21:31] <slick> any idea how to fix this?
[21:32] <slick> what fps to set etc?
[21:32] <jure> could be any number of things, really
[21:32] <slick> name a few? so i can check them plz
[21:33] <jure> codec settings, for instance
[21:33] <slick> if u think it wud be faster can we try teamviewer? im new to this kinda stuff
[21:33] <Mavrik> !pbb slick
[21:34] <slick> ill give u the whole ouput if u want
[21:34] <slick> im guessing that wud be best right?
[21:34] <Mavrik> yeah
[21:34] <slick> ok 1sec
[21:34] <Mavrik> since that has the information about whats going on :)
[21:35] <slick> http://pastebin.com/dKY9U5W4
[21:37] <Mavrik> ugh
[21:37] <Mavrik> flv.
[21:37] <Mavrik> 200kbit.
[21:37] <Mavrik> that probably looks like barf :D
[21:37] <slick> lol wut setting shud i use then
[21:37] <jure> -c:v libx264 -crf 0 -preset ultrafast
[21:38] <Mavrik> what jure said :D
[21:38] <Mavrik> crf 0 is losless
[21:38] <slick> :\ im newb can u give me the whole command for that lol
[21:38] <slick> id mess it up knowing me
[21:38] <Mavrik> slick, add jure's parameters before output.flv
[21:38] <jure> ffmpeg -f x11grab -r 25 -s 854x480 -i :0.0+151,215 -c:v libx264 -crf 0 -preset ultrafast output.mp4
[21:38] <slick> ok
[21:38] <slick> ty
[21:38] <Mavrik> you can change crf 0 to something like crf 24 to get more compression if the file is too large
[21:38] <Mavrik> play with crf until you get the size/quality you want
[21:39] <slick> ok sweet ty ill bbs ima go try it out
[21:40] <brontosaurusrex> crf 0 = lossless, so you can use that as imtermediate before recompressing to something smaller using a smarter preset later on
[21:52] <slick> it plays too fast what should i try?
[21:53] <slick> change crf? i have 3gb ram and 2.8ghz on kde4 kwin and i can switch to blackbox if i have2
[21:55] <jure> play around with -r ...
[21:55] <jure> try -r 30, -r 60
[21:55] <slick> ok ty
[22:05] <slick> oddly enuff when i lowered -r im guessing fps it acted normally with 10
[22:05] <slick> any idea why?
[22:07] <slick> any1?
[22:10] <slick> well bye im gonna go try blackbox lol
[00:00] --- Mon Aug 12 2013


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