[Ffmpeg-devel-irc] ffmpeg.log.20140619

burek burek021 at gmail.com
Fri Jun 20 02:05:01 CEST 2014


[00:05] <Spacexplosion> ok, one moment
[00:32] <Spacexplosion> ok c_14, sorry for the delay
[00:32] <Spacexplosion> error output: http://pastebin.com/dTNMVZVB
[00:33] <Spacexplosion> codecs list: http://pastebin.com/Eda4ahrn
[00:35] <Spacexplosion> I'
[00:36] <c_14> I think the problem is that ogg doesn't support subrip subtitles
[00:36] <Spacexplosion> eh, really?
[00:38] <c_14> So according to wikipidia (cause I couldn't find a better source), ogg supports writ, continuous media markup language, annodex and oggkate
[00:39] <Spacexplosion> huh, that didn't even occur to me
[00:39] <Spacexplosion> I'm looking at another ogg I have, and it has subs encoded as just "text"..
[00:39] <Spacexplosion> Stream #0:3(English): Subtitle: text
[00:39] <llogan> why theora (and ogg)? there are usually better alternatives these days
[00:40] <Mephistos> hi guys, any idea what output format/codec I can use with -pix_fmt rgb48le.  I think that will give me more info converting from a bayer pixel format than rgb24.
[00:40] <Spacexplosion> llogan: I know; not my choice. it's for a special purpose. ;)
[00:41] <Spacexplosion> so if I set the sub codec to something else, like "text" it should work?
[00:42] <Spacexplosion> not sure how raw text has any timing info...
[00:42] <Mephistos> The input file is a MLV which has bayer_rggb16le as the pixel format and I think that I'm losing a lot of info when it's converting to rgb24, 16 bits per color to 8 bits.
[00:42] <c_14> technically yes, practically it depends on if the source codec is picture or text and if ffmpeg has an encoder for the output format
[00:46] <Mephistos> Hmm... I think I just found the issue...  using r210 as the codec...
[00:46] <llogan> Spacexplosion: you could always make hardsubs if you really need subtitles and if ogg is being dumb for subtitles (i don't know shit about ogg 'n subtitles)
[00:47] <llogan> Mephistos: ffmpeg -h encoder=<name> will list supported pixel formats for each encoder
[00:47] <Spacexplosion> well, I was having trouble with that too. I was trying to use the "subtitles" video filter, but it claims that doesn't exist
[00:47] <Mephistos> oh yeah?
[00:47] <Mephistos> is there a way to do the reverse, see which codecs fit the pixel formats?
[00:48] <llogan> i'm not sure
[00:49] <Mephistos> I just did that and I get the options for ffmpeg but not the pixfmts
[00:49] <llogan> Mephistos: also the format and/or noformat filters may be use(ful|less) at some point
[00:50] <Mephistos> yeah, I've got a pastebin for you
[00:50] <Mephistos> I found r210 is compatible with rgb48le
[00:50] <llogan> <- paste addict
[00:50] <Mephistos> but I encountered a completely different issue, which is probably because we're all in new territory when it comes to raw video.
[00:50] <Mephistos> You'll like this one then... it's new.
[00:51] <Mephistos> http://pastebin.com/FrMcJX5a
[00:52] <Spacexplosion> what you want me to paste?
[00:52] <Mephistos> They want to see the output and full command line used
[00:52] <Spacexplosion> the error about subtitles filter?
[00:53] <Mephistos> They want the full output and command line of ffmpeg, that should also include that error.
[00:54] <Mephistos> take a look at my pastebin, it will give you an idea
[00:55] <llogan> Mephistos: i was referring to your -h issue. unfortnately I don't know what to suggest for "full chroma interpolation for destination format 'rgb48le' not yet implemented" unless you know C and want to give a go at implementing it. some users on ffmpeg-user ML might know more
[00:55] <llogan> Spacexplosion: yes. subtitles filter issue.
[00:56] <Spacexplosion> k, I don't have the command I was using handy. I'll have to fiddle with it
[00:56] <llogan> Mephistos: ffmpeg -pix_fmts might interest you
[00:57] <Mephistos> Oh I know, I've been using that to see what's baked into my compile of a recent snapshot, but the pix_fmts list doesn't tell me which codecs work with them.
[00:58] <Mephistos> I was able to google one that worked for testing purposed, r210, and it no longer converts it to rgb24...
[00:58] <Mephistos> no idea why that even works
[00:59] <Mephistos> I was testing using huffyuv, which
[00:59] <Mephistos> causes it to convert to rgb24
[00:59] <Mephistos> but bayer formats are weird
[01:00] <Mephistos> they are grgrgrgrgrg on one row, then gbgbgbgbg on the next row.  So the conversion isn doesn't work, it's taking each pixel and converting it to
[01:00] <Mephistos> whoops
[01:00] <Mephistos> let me try that line again
[01:01] <Mephistos> they are grgrgrgrgrg on one row, then gbgbgbgbg on the next row.  So the conversion isn't being done in a sane way, it's taking each pixel and converting it to 8bits or red green or blue...  But the catch is there's no demosiac process being done!
[01:02] <Spacexplosion> llogan: subtitle filter error: http://pastebin.com/6HZMB9t7
[01:02] <Spacexplosion> filters: http://pastebin.com/9aQ9Ve7u
[01:02] <Spacexplosion> sure enough, "subtitles" isn't listed as a filter
[01:03] <Spacexplosion> all I have support for is ssa apparently
[01:03] <Spacexplosion> I wouldn't think the generic "subtitles" filter would be conditionally built
[01:04] <Spacexplosion> I'm running Gentoo, and it's not a USE flag
[01:05] <c_14> you're running ffmpeg version 1.08
[01:05] <c_14> that version is ancient
[01:06] <Spacexplosion> and Gentoo is supposed to be so bleeding edge :P
[01:06] <c_14> try unmasking 2.2.3-r1 or 9999
[01:06] <c_14> Always use the newest ffmpeg possible, preferably git head.
[01:07] <Spacexplosion> wonder why it is masked back to such an old version...
[01:10] <c_14> according to the bugtracker because some optional dependencies are masked
[01:21] <Mephistos> I think I see what's going on.  The bayer conversion thing is probably going to be a huge new direction for the ffmpeg project, and there's tonnes of code out there from other projects, specifically darktable, which is the best and most complete raw image editing project out there, for stills.... but they have everything ready made and work within a 4x32 floating point pixel buffer space, which is insane.
[01:29] <paxromain> Hey everyone!
[01:29] <paxromain> anyone seen c_14 around?
[01:29] <llogan> Mephistos: peter ross would probably be the guy to talk to: https://trac.ffmpeg.org/wiki/FFmpegSummerOfCode2014#BayerRGBcolorspaces but i'm not sure what the current status of any beyer stuff is
[01:30] <paxromain> hey llogan what's going on?
[01:30] <llogan> procrastinatin
[01:33] <Mephistos> llogan, it's probably at a very initial primitive state, thanks for the link, this is cool.  I'll message Michael.  I have a feeling that a different kind of overview needs to be looked at for how bayer is handled.
[01:36] <Spacexplosion> oh wow, boy does ffmpeg 2.2.3-r1 ever depend on a lot of other masked stuff
[01:37] <RadSurfer> avidemux appears to be a sweet program, working great here so far... Win8.1/quadcore
[01:37] <RadSurfer> works great with ffmpegs .mkv's
[01:37] <BtbN> never got avidemux to do much more than creating broken videos and/or crashing.
[01:38] <RadSurfer> well, have U tried latest version? also have 8gb ram, I'm sure that helps
[01:38] <RadSurfer> 2012... last version?
[01:39] <RadSurfer> I'll try it this week and maybe get back to you, what little testing I've done is impressive for a freeby
[01:45] <RadSurfer> If I wanted ffmpeg to merely append/combine .vob files into one (and/or create .mkv), can someone please suggest a command line syntax
[01:45] <c_14> https://trac.ffmpeg.org/wiki/How%20to%20concatenate%20(join,%20merge)%20media%20files
[01:56] <Mephistos> llogan,  I don't see a way to contact Peter Ross, only Michael, his backup mentor.
[04:03] <RadSurfer> Where is the documentation to control increasing the playback rate of the input file, when encoded to "normal rate" for output file?
[04:04] <c_14> playback rate as in fps?
[04:05] <RadSurfer> yeah... I must increase -i file by 2.4375
[04:05] <RadSurfer> times its normal speed
[04:06] <RadSurfer> https://trac.ffmpeg.org/wiki/How%20to%20speed%20up%20/%20slow%20down%20a%20video
[04:06] <c_14> the setpts filter is documented in ffmpeg-filters, if that's what you're looking for
[04:07] <c_14> But if you want to speed up by 2.4375, setpts=(1/2.4375)*PTS should do the trick
[04:07] <RadSurfer> Thank you.
[04:16] <llogan> atempo for audio if you need that
[04:28] <RadSurfer> Hmm. wasn't expecting that
[04:28] <RadSurfer> aspect ratio is all wrong
[05:24] <RadSurfer> WHERE is the ffmpeg doc page that describes -aspect please? I found -scale
[05:25] <sacarasc> http://ffmpeg.org/ffmpeg-all.html
[05:27] <RadSurfer> I was hoping it would shed some light on " scale vs aspect ratio "
[05:27] <sacarasc> Scale sets how many pixels there are, aspect sets what shape it is.
[05:28] <RadSurfer> It's shape I am concerned about.
[05:28] <RadSurfer> I thought I used to know this, but haven't worked with it in ages
[08:14] <zzw> hello everyone, who can tell me the difference of "mpegts" and "mepgtsraw" demuxer?
[08:21] <zzw> i want to perform real-time demuxing and playing  mpegts ,but i find the avformat_open_input function waste too much time
[08:47] <zzw> hello everyone, who can tell me the difference of "mpegts" and "mepgtsraw" demuxer?
[08:47] <zzw> i want to perform real-time demuxing and playing  mpegts ,but i find the avformat_open_input function waste too much time
[09:08] <Guest68998> ive got some issues when trying to compile ffmpeg , getting error relocation R_ARM_THM_MOVW_ABS_NC against `ff_avg_pixels16_x2_neon' can not be used when making a shared object; recompile with -fPIC libavcodec/arm/hpeldsp_init_neon.o: could not read symbols: Bad value collect2: error: ld returned 1 exit status make: *** [libavcodec/libavcodec.so.55] Erreur 1
[09:08] <Guest68998> any clue what this might be?
[11:25] <decembersoul1> Hello, is there a way that ffserver + ffmpeg only transcode the stream if a consumer is connected.
[11:25] <decembersoul1> Mjpeg stream -> ffmpeg -> h265 -> ffserver -> listener
[11:25] <decembersoul1> If no one listen to the stream we don't need to create the stream
[11:26] <Mavrik> no.
[11:28] <decembersoul1> in some cases (fast entrance into stream) it is usefull, but in some cases it is a waste of CPU Power
[14:33] <Swoxxx> Hi, any of you know an opensource solution that would allow us to **render** videos server-side and headless? With a template video that would have placeholders, where we would insert some pictures and then render the video
[14:33] <Swoxxx> Serverside, dynamically, headless if possible
[14:34] <Swoxxx> If you have any idea about this, I'm more than willing to know about it
[14:43] <Esya> Hi, does anyone know where I can ask a question about headless video rendering on unix? (Not encoding, actual rendering)
[14:43] <Esya> or compositing actually.
[14:44] <klaxa|work> ffmpeg video filters maybe?
[14:44] <Esya> klaxa|work Hmm.. Not sure if that would work but let me give a quick example
[14:45] <Esya> Lets say we have a first video with characters moving but they have no faces. We also have user pictures, and we would need to compose their faces onto the characters
[14:46] <klaxa|work> and you want that to be done headless?
[14:46] <Esya> Not necessarily headless, I can use a X server, but automatically for sure
[14:46] <Esya> A bit like facebook lookback videos
[14:47] <klaxa|work> maybe you can use some tracking stuff with cinelerra
[14:47] <Esya> Hmm, it does not necesarrily imply tracking as it will be done only once and the source/background video will always be the same
[14:47] <Esya> So we can feed whatever we will use the right coordinates to use if needed
[14:48] <Esya> (But I am going to look at cinelerra, which I didnt know, and thanks for that)
[14:51] <Esya> klaxa|work Actually someone has suggested using blender in headless/server mode and said that even if it's not exactly 3d, it could work well
[14:51] <klaxa|work> oh yeah i heard such things about blender too
[15:31] <JEEBsv> I recommend you drop libaacplus, and instead use fdk-aac
[15:31] <JEEBsv> aand here I was way up in the buffer
[15:31] <JEEBsv> herp derp
[15:45] <Mavrik> :))
[16:13] <Fjorgynn> i see
[16:13] <Fjorgynn> JEEBsv: fdk aac ftw
[18:21] <maksimkaaa> I have a normal 4 seconds OGV movie generated from 4 images, whenever I try to generate an MP4 out of it, the resultant mp4 is just 2 seconds long with 2 frames.. here is the log of the ffmpeg command http://pastebin.com/H1ryAFFH The command itself was just ffmpeg -i 7_4499.ogv test1.mp4
[18:34] <llogan> maksimkaaa: can you provide the input?
[18:40] <maksimkaaa> llogan you mean the ogv file itself?
[20:23] <RadSurfer> ffmpegs default .mkv file video plays aok on my dvd player _except_ for "audio is not supported", I will have to over-ride encoding audio for that to be compatible apparently
[20:26] <RadSurfer> I wonder what the common-most audio format for dvd-players/internet-tv devices would be?
[20:28] <c_14> DVDs usually have somethnig alonng the lines of pcm,dts,mp2 or ac3.
[20:29] <RadSurfer> I am trying to reduce size of my camcorders .mp4 files; video is displaying just fine!
[20:29] <RadSurfer> So what would you recommend I try to audio options, please?
[20:30] <RadSurfer> /s/to/for
[20:31] <c_14> What's your source audio format?
[20:32] <RadSurfer> isn't there a way to have ffmpeg tell me?
[20:33] <c_14> ffprobe $file
[20:34] <RadSurfer> audio encoder : Samsung AVC Encoder Stream #0:1(eng): Audio: aac (mp4a / 0x6134706D), 24000 Hz, stereo, fltp, 12
[20:34] <RadSurfer> 3 kb/s (default)
[20:35] <RadSurfer> so its just aac?
[20:35] <c_14> I'd probably use AC-3 if you're looking for compatibility and filesize requirements.
[20:57] <RadSurfer> this seems to work for me now:
[20:57] <RadSurfer> ffmpeg -i "file.MP4" -aspect "16:9" -vf yadif -c:a copy -c:v libx264 "movie0.mkv"
[20:58] <RadSurfer> although I don't really need -aspect in there
[20:58] <RadSurfer> 1/5th original size! lol
[20:59] <RadSurfer> nearly
[23:17] <miep1> I need some help on how to achieve something with libav*. I'm trying to set up something that filters out all audio from a regular video
[23:18] <miep1> I can't seem to find the relevant example in doc/example
[23:18] <miep1> Any pointers on where to look?
[00:00] --- Fri Jun 20 2014


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