[Ffmpeg-devel-irc] ffmpeg.log.20151108

burek burek021 at gmail.com
Mon Nov 9 02:05:01 CET 2015


[00:02:43 CET] <zumba_ad_> can ffmpeg apply a film effect look?
[00:02:58 CET] <zumba_ad_> like the colors used in the movie Transformers
[00:03:39 CET] <c_14> I have no idea.
[00:03:42 CET] <c_14> Maybe use the hue filter?
[00:04:13 CET] <zumba_ad_> k
[00:59:18 CET] <jorb> ahh finally got that damn vid to work properly
[00:59:54 CET] <jorb> ChocolateArmpits initial advice was correct .. needed this -ac 2 flag
[01:18:15 CET] <ChocolateArmpits> jorb: what/
[01:18:17 CET] <ChocolateArmpits> ?
[01:46:06 CET] <ffmfailure> I have a really shitty question.
[02:28:56 CET] <Prelude_Zzzzz> hey guys... can someone help me... http://216.87.168.92/test.ts < ==== look at the last few seconds of video when she moves. content is coming in at 29.97fps and i have it encoding at 30fps. Not all content does that so i am lost. Some commercials and content are smooth and other content like that are stuttering like crazy... can anyone point me in the right direction as to what can cause it or fix it ?
[02:34:12 CET] <Prelude_Zzzzz> anyone?
[02:34:37 CET] <c_14> Do you mean the ghosting?
[02:35:44 CET] <ParkerR> Any tips for speeding up a video to 120FPS? I recorded a sample on my Nexus 5X but the original video it saves is 29.64FPS. The Photos application on the phone presumably speeds it up in real time to view it. Is there any easy way to do this with ffmpeg? http://ix.io/lZY
[02:36:29 CET] <c_14> Like fast-forwarding on analog media (kinda)?
[02:36:31 CET] <c_14> Use setpts
[02:36:47 CET] <ParkerR> Ive been playing with that
[02:37:00 CET] <ParkerR> Still trying to find the right values
[02:37:14 CET] <Prelude_Zzzzz> yup ghosting i guess
[02:37:31 CET] <c_14> Prelude_Zzzzz: usually due to incorrect deinterlacing
[02:37:35 CET] <ParkerR> c_14, Yeah thats a good (analog)y lol
[02:37:38 CET] <Prelude_Zzzzz> how do you get rid of ghosting
[02:37:44 CET] <Prelude_Zzzzz> really? so i should deinterlace ?
[02:38:08 CET] <c_14> If the content is already progressive you lose. If not, it should be fine as long as you deinterlace correctly.
[02:38:23 CET] <c_14> ParkerR: what values did you try and what wasn't working about it?
[02:39:28 CET] <ParkerR> c_14, Well the trac example for setpts just gives a double speed example. I assume since its 30 > 120FPS it would need to be 4x
[02:40:00 CET] <c_14> So use 0.25 instead of 0.5?
[02:40:11 CET] <c_14> setpts=0.25*PTS
[02:40:31 CET] <Prelude_Zzzzz> i am not sure i understand that whole deinterlace thing
[02:40:40 CET] <c_14> or if you really just want the 120FPS, use setpts=N/(140*TB)
[02:40:40 CET] <Prelude_Zzzzz> if progressive i loose ?
[02:40:41 CET] <ParkerR> Will try. Also what would the audio value have to be changed to? ffmpeg -i input.mkv -filter_complex "[0:v]setpts=0.5*PTS[v];[0:a]atempo=2.0[a]" -map "[v]" -map "[a]" output.mkv
[02:40:42 CET] <Prelude_Zzzzz> was that for me
[02:40:51 CET] <c_14> Prelude_Zzzzz: yes
[02:40:55 CET] <ParkerR> Ahh atempo 4.0 would make sense
[02:41:06 CET] <c_14> If the video is progressive, it was already deinterlaced incorrectly and the ghosting is now a part of the video.
[02:41:20 CET] <Prelude_Zzzzz> oh ic... but if not it will deinterlace it
[02:41:35 CET] <Prelude_Zzzzz> ok... so i set something like this " -vf "yadif=deint=interlaced"
[02:41:45 CET] <c_14> You can use the idet filter to check if it's interlaced.
[02:41:46 CET] <ParkerR> c_14, [atempo @ 0x563e7342f2c0] Value 4.000000 for parameter 'tempo' out of range [0.5 - 2]
[02:42:03 CET] <c_14> It will also set the interlaced flag so -vf "idet,yadif=deint=interlaced" should work
[02:42:16 CET] <Prelude_Zzzzz> got it... will use more cpu i guess
[02:42:19 CET] <c_14> ParkerR: atempo=2,atempo=2
[02:42:55 CET] <c_14> Each atempo has a max  of 2, but you can combine them
[02:43:20 CET] <ParkerR> So "[0:v]setpts=0.5*PTS[v];[0:a]atempo=2,atempo=2[a]" ?
[02:43:29 CET] <c_14> And it's multiplicative, so atempo=2,atempo=2,atempo=2 would be an increase of 8, not 6
[02:43:36 CET] <furq> Prelude_Zzzzz: try deinterlacing it in your player before encoding
[02:43:36 CET] <c_14> setpts=0.25*PTS
[02:43:38 CET] <c_14> but yes
[02:43:43 CET] <ParkerR> Yeah
[02:43:45 CET] <furq> also try IVTC'ing it
[02:43:50 CET] <ParkerR> I was just cpying from my paste above lol
[02:43:55 CET] <ParkerR> *copying
[02:44:37 CET] <Prelude_Zzzzz> ehh i am just going to turn the vf filter on
[02:44:45 CET] <Prelude_Zzzzz> it should work automatic right ? to only deinterlaced.. interlaced content
[02:44:57 CET] <ParkerR> c_14, HAHA atempo worked but pitch is skewed
[02:45:02 CET] <ParkerR> Still sound like a demon
[02:45:05 CET] <Prelude_Zzzzz> so if i set that vf "idet,yadif=deint=interlaced" i should not worry about it anymore
[02:45:48 CET] <c_14> ParkerR: atempo shouldn't change the pitch
[02:46:04 CET] <c_14> Prelude_Zzzzz: ye
[02:46:16 CET] <Prelude_Zzzzz> cool.. also refs. why should i use that in live video
[02:46:27 CET] <Prelude_Zzzzz> will it help me reduce file sizes and maintain quality?
[02:46:42 CET] <ParkerR> c_14, Thats the issue. I need it to speed the audio up to sound normal too
[02:47:04 CET] <Prelude_Zzzzz> i have no -refs flag set right now
[02:47:20 CET] <Prelude_Zzzzz> and i can't understand the relationship at the moment.. i am thinking if we have more reference frames maybe better quality ?
[02:48:28 CET] <c_14> It just sets the amount of frames to look at for motion compensation.
[02:52:03 CET] <c_14> ParkerR: I just tested and the pitch doesn't shift.
[02:52:59 CET] <c_14> Really easy to test if you just generate a constant sine wave.
[02:54:01 CET] <ParkerR> Is there a way to adjust the pitch too?
[02:55:22 CET] <c_14> You can try asetrate (which will work but isn't pretty and will change the samplerate), or get a build built against librubberband and use the rubberband filter.
[02:59:20 CET] <ParkerR> c_14, Here's a sample file (Has to be downloaded. Doesnt play in browser (at least in firefox)) http://a.pomf.hummingbird.moe/srlyhi.mp4
[03:03:08 CET] <c_14> Pitch stays the same for me.
[03:03:54 CET] <ParkerR> Yep.
[03:04:00 CET] <c_14> You want it to increase?
[03:04:07 CET] <ParkerR> Ideally
[03:04:15 CET] <ParkerR> So it appears like like a normal video
[03:04:24 CET] <ParkerR> *just like
[03:07:38 CET] <c_14> You can use asetrate=192000
[03:08:05 CET] <c_14> That or build ffmpeg with librubberband
[03:08:15 CET] <ParkerR> "[0:v]setpts=0.25*PTS[v];[0:a]atempo=2,atempo=2,asetrate=192000[a]" ?
[03:08:40 CET] <c_14> Without the atempos
[03:08:54 CET] <ParkerR> Ahh
[03:09:09 CET] <c_14> I think you need a recent git build for that though.
[03:09:17 CET] <ParkerR> c_14, Would "libruberband" show up when running just "ffmpeg" if it was built with it?
[03:09:52 CET] <c_14> it would say --enable-librubberband, yes. You can also check ffmpeg -filters for 'rubberband'
[03:10:51 CET] <ParkerR> Yay asetrate worked
[03:10:56 CET] <ParkerR> Using ffmpeg in Arch
[03:11:04 CET] <ParkerR> c_14, Thanks for all the help
[03:11:20 CET] <ParkerR> ffmpeg -i VID_20151107_194515.mp4 -filter_complex "[0:v]setpts=0.25*PTS[v];[0:a]asetrate=192000[a]" -map "[v]" -map "[a]" -strict -2 output.mp4
[03:14:45 CET] <c_14> Do note, the samplerate of the video is now 192KHz, you should be able to append an aresample filter though to cut it down if you have to (not all players may support samplerates that high)
[03:16:50 CET] <ParkerR> Yeah Firefox still complains
[13:35:28 CET] <waressearcher2> hallo
[17:19:17 CET] <Kartagis> hi
[17:19:22 CET] <waressearcher2> Kartagis: hallo
[17:20:09 CET] <Kartagis> all questions about avconv on google lead me to ffmpeg, so can I ask an avconv question here_
[17:20:40 CET] <Kartagis> s/_/?/
[17:20:58 CET] <JEEB> no, avconv is only in libav
[17:21:11 CET] <JEEB> ffmpeg only has ffmpeg
[17:22:17 CET] <JEEB> although generally a new ffmpeg's generally command line usage is pretty much the same as new avconv's
[17:22:29 CET] <JEEB> since elenril's changes to the syntax were merged in and all a few years back
[17:22:32 CET] <Kartagis> why does ffmpeg tell me to use avconv because it will be deprecated soon?
[17:22:38 CET] <JEEB> that's within the Libav project
[17:22:49 CET] <JEEB> it use to have ffmpeg binary as well which had the old syntax
[17:22:51 CET] <JEEB> *used
[17:23:04 CET] <JEEB> FFmpeg's ffmpeg is alive and well
[17:23:04 CET] <Kartagis> hm
[17:23:18 CET] <JEEB> Libav then removed the not-updated ffmpeg during the next release
[17:23:34 CET] <Kartagis> oh, there are two ffmpeg's
[17:24:12 CET] <JEEB> well, if you still have Libav 0.8 then you have quite an old system
[17:24:57 CET] <JEEB> anyways, at this point FFmpeg only has ffmpeg, and Libav only has avconv, since they removed their ffmpeg (which was a binary that had the old syntax when they rewrote a lot of parameter usage)
[17:25:12 CET] <JEEB> and since FFmpeg merged that work, both ffmpeg in FFmpeg and avconv in Libav share this
[17:25:42 CET] <JEEB> in any case, 0.8 Libav is ancient so if you want to use anything like that I recommend you update to the latest FFmpeg or Libav
[17:25:58 CET] <JEEB> there are static builds linked in the topic, IIRC
[17:26:37 CET] <bencoh> isnt there a bot with a link to some post to explain all that?
[17:26:41 CET] <bencoh> ~fork
[17:26:43 CET] <bencoh> hmm
[17:26:59 CET] <JEEB> that link IIRC was not really trying-to-be-neutral, although I might be incorrect
[17:27:10 CET] <bencoh> ah, could be
[17:27:27 CET] <Kartagis> Package ffmpeg is not available, but is referred to by another package.
[17:27:30 CET] <bencoh> (I might be a bit biased myself too)
[17:27:30 CET] <Kartagis> heh
[17:28:03 CET] <JEEB> Kartagis: yeah your package manager most probably only has one and that's Libav - in any case the version you'd have would be old in the package manager
[17:28:14 CET] <JEEB> you'd have to compile yourself or use a static binary
[17:28:33 CET] <JEEB> oh, the topic no longer has those binaries
[17:29:10 CET] <JEEB> http://johnvansickle.com/ffmpeg/
[17:29:30 CET] <JEEB> just put the ffmpeg binary somewhere in PATH
[17:29:51 CET] <JEEB> shouldn't cause trouble as long as you don't try to replace a system-installed binary with it
[19:53:36 CET] <abd5932> Hi, I would like to put several strings on my video. There is drawtext filter. What is the best way to use it, if I have 6-8 different strings/coords/fontsize? - is it possible to write them all to a file or should I pass it through the comand line?
[19:53:41 CET] <abd5932> Thank you!
[20:25:30 CET] <nyuszika7h> it seems like -vf ass is adding an extra pixel of outline to ASS subtitles :/
[20:26:07 CET] <JEEB> have you compared it to other libass-using applications' results?
[20:26:33 CET] <nyuszika7h> I've compared it to MPC-BE (using XySubFilter), yes
[20:26:41 CET] <JEEB> that doesn't use libass
[20:26:45 CET] <nyuszika7h> oh
[20:27:08 CET] <JEEB> and while vshitler is more or less the reference, all of the forks of it are giving a different result in one way or another
[20:27:54 CET] <JEEB> so I recommend you checking with something using the latest HEAD libass
[20:28:21 CET] <JEEB> you could build mpv with mpv-build with it, or check if lachs0r's builds contain it
[20:28:29 CET] <nyuszika7h> yeah I have mpv I can check with that
[20:28:48 CET] <JEEB> after checking that result you can check if the difference is due to libass or if it's something specific to vf ass
[20:29:08 CET] <nyuszika7h> anyway, I'll just add one pixel less outline for now, I'm hardcoding subtitles for my TV because it does not outline them properly and they are often hard to read >_>
[20:30:11 CET] <JEEB> and even after that you can't strictly say which render is actually "correct" until you give out a sample and have it checked (that is unless it's vf ass specific, in which case you make sure which libass version is used and if it's older just note to the person whose builds you use to use a newer one)
[20:30:24 CET] <nyuszika7h> hmm, I need to reduce the shadow too
[20:31:13 CET] <JEEB> I guess you're using aegisub for the subtitle creation part?
[20:31:37 CET] <abd5932> Hi, I would like to put several strings on my video. There is drawtext filter. What is the best way to use it, if I have 6-8 different strings/coords/fontsize? - is it possible to write them all to a file or should I pass it through the _long_ command line?
[20:31:45 CET] <nyuszika7h> yes
[20:32:18 CET] <nyuszika7h> well, I already have the subtitles, I just convert them to ASS and change the style to look like MPC's defaults
[20:34:15 CET] <nyuszika7h> I've set both outline and shadow to 1px now rather than 2 and 3, the result is close enough
[20:34:42 CET] <nyuszika7h> mpv seems to render my styled subtitles like MPC too
[20:34:57 CET] <JEEB> probably a case of old libass then in your ffmpeg
[20:35:03 CET] <JEEB> make sure you've built with the latest HEAD
[20:36:01 CET] <nyuszika7h> ffmpeg-20151028-git-dd36749-win64-static
[20:36:43 CET] <JEEB> no idea what that contains :P
[20:36:55 CET] <JEEB> check whomever's build you got
[20:37:00 CET] <nyuszika7h> http://ffmpeg.zeranoe.com/builds/ lists the external libs
[20:38:18 CET] <nyuszika7h> can't find a libass update in the changelogs since that version
[20:38:24 CET] <nyuszika7h> but I'm getting the latest anyway
[20:38:40 CET] <nyuszika7h> actually, wait
[20:39:12 CET] <nyuszika7h> I said it wrong, mpv renders it like ffmpeg, with 1 outline and shadow
[20:39:54 CET] <nyuszika7h> in MPC I can barely see the outline and shadow, but it doesn't matter because I'm only restyling the subtitles to be hardcoded anyway, so I'll just use 1px outline and shadow
[20:42:07 CET] <nyuszika7h> (oh also the result is the same with -vf ass and -vf subtitles, too)
[20:47:06 CET] <JEEB> yeah, then it's a libass | vshitler thing (or possibly dependant on your rendering resolution)
[21:02:30 CET] <nyuszika7h> o_O I found another weird rendering difference between libass and XySubFilter
[21:02:46 CET] <nyuszika7h> not sure which is correct, but one puts one line on the top, and the other puts the other line on the top
[21:14:17 CET] <basisbit> so, I did some more testing but still am not able to figure out how to get the different frame types to play in correct order when using low latency flag. (Regarding: "hey, using ffmpeg 2.8.1, I am having issues with video playback of certain avi files when using CODEC_FLAG_LOW_DELAY. It mixes up the frames. So you see frame2, then frame 1, then frame 4 then frame 3 and so on. When not using CODEC_FLAG_LOW_DELAY, everything plays nicely. This is a karaoke
[21:14:17 CET] <basisbit> software, so a log audio to video delay is essential for good experience. Any idea how to fix this?
[21:14:17 CET] <basisbit> ")
[21:14:59 CET] <nyuszika7h> https://imgur.com/a/Tr49E (ignore the credits, it's not the exact same frame)
[21:15:16 CET] <basisbit> I think that the different frame types are not played in correct order but instead just as stored in the file
[21:17:44 CET] <jgarde> Can anyone tell me what type of data is in this H264 stream header and how I would access it?
[21:17:45 CET] <jgarde> https://i.imgur.com/eVZYfeD.png
[21:50:28 CET] <waressearcher2> jgarde: hallo
[21:51:05 CET] <jgarde> waressearcher2: heyo
[21:51:13 CET] <waressearcher2> jgarde: wie gehts ?
[21:51:14 CET] <darktoad> yellow
[21:52:07 CET] <jgarde> waressearcher2: Ich spreche kein Deutsch.
[22:47:56 CET] <zhanshan> hi I run ffmpeg version 2.6.git
[22:48:06 CET] <zhanshan> how can I easily upgrade to last version?
[22:53:23 CET] <yumbox> what does this mean? [ffmpeg] NULL: start time for stream 0 is not set in estimate_timings_from_pts
[23:07:02 CET] <waressearcher2> yumbox: hallo
[23:07:38 CET] <yumbox> hi
[23:07:47 CET] <yumbox> waressearcher2
[23:09:17 CET] <waressearcher2> yumbox: wie gehts ?
[23:09:33 CET] <yumbox> ich spreche keine deutsch :/
[00:00:00 CET] --- Mon Nov  9 2015


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