[Ffmpeg-devel-irc] ffmpeg.log.20151128

burek burek021 at gmail.com
Sun Nov 29 02:05:01 CET 2015


[01:08:36 CET] <infinmed> Hi, my -aspect 16:9 when making an ntsc dvd5 is actually converting my video via upscale to that resolution, i already upscale and pad with filters
[01:08:43 CET] <infinmed> i just want to set the number in the media
[01:08:47 CET] <infinmed> What might I do
[01:10:09 CET] <infinmed> One sec I"ll show you my line
[01:11:02 CET] <infinmed> ffmpeg -threads 6 -i "$1" -y -c:v mpeg2video -c:a ac3 -b:v 4250k -b:a 384k -q:v 1 -q:a 1 -async 1 -threads 6 -mbd rd -trellis 2 -cmp 2 -subcmp 2 -timecode 01:02:03.04 -r 30000/1001 -s ntsc -filter:v "scale='w=720:h=480',pad='720:480'" -aspect 16:9 -subq 2 -qcomp 0.7 -bf 2 -pass 1 -y -f dvd movie.mpg
[01:11:30 CET] <infinmed> Well cancel the -q's i removed those
[01:12:03 CET] <infinmed> That's jsut when i'm trying to two pass on a small video and ffmpeg wants to hit 1.6 and 2.0
[01:12:10 CET] <furq> infinmed: i think you want -vf setdar
[01:12:11 CET] <infinmed> which means i might just crf
[01:12:12 CET] <c_14> Why are you scaling twice?
[01:12:23 CET] <c_14> and then padding to the hight you just scaled
[01:12:25 CET] <infinmed> although anyways back to the question
[01:12:26 CET] <c_14> this makes no sense
[01:12:55 CET] <infinmed> I'm not scaling twice that's exactly what i'm trying to say, well i'm not trying to it's just if i don't add -aspect 16:9
[01:13:06 CET] <infinmed> Well, then I end up with dvdauthor with a 4:3 and not knowing what an ar of 4 is
[01:13:14 CET] <c_14> >-s ntsc -filter:v scale=
[01:13:17 CET] <infinmed> Are you teling me -aspect will accomplish that exact filter
[01:13:20 CET] <c_14> Those are both inserting scale filters
[01:13:34 CET] <infinmed> Alright noted
[01:13:59 CET] <infinmed> Which one aught to I keep in yoru recomendation
[01:14:05 CET] <infinmed> Becauswe if i take the -aspect out of there and play it with vlc
[01:14:11 CET] <infinmed> It's ar is correct
[01:14:15 CET] <infinmed> It's not stretched to 16:9
[01:14:17 CET] <c_14> I'm not even sure what resolution ntsc corresponds to
[01:14:19 CET] <c_14> I'd remove that one
[01:14:27 CET] <infinmed> 16:9 or 4:3
[01:14:36 CET] <infinmed> that's why i need to pad and crop
[01:14:36 CET] <infinmed> me too thanks
[01:14:38 CET] <infinmed> will do
[01:14:52 CET] <c_14> Also, the pad is redundant
[01:14:54 CET] <infinmed> Any idea on how to just set this aspect ratio and not let -aspect actually scale and pad
[01:15:06 CET] <c_14> You're already scaling to that side, padding to the same size won't change anything
[01:15:23 CET] <c_14> If you really only want a dvd, I'd just recommend using -target ntsc-dvd
[01:15:35 CET] <infinmed> Without the pad i wouldn't have letterboxes on higher width videos
[01:15:44 CET] <infinmed> no?
[01:15:48 CET] <c_14> you won't have them with your current command either
[01:16:08 CET] <infinmed> Alright well i'll just finger f' i figured it's more efficient to ask someone
[01:17:06 CET] <infinmed> Scientific method, test and observe =]
[01:17:08 CET] <infinmed> Thanks for the help
[01:17:13 CET] <c_14> I'd probably start with only using -target ntsc-dvd, and then find out what happens
[01:17:22 CET] <c_14> Most of your options are in conflict with each other
[01:17:36 CET] <c_14> You're setting both a video and audio bitrate, but then also setting a quality
[01:17:39 CET] <infinmed> I don't like that as you are at a moment wwhere libav and ffmpeg are like, you know
[01:17:51 CET] <infinmed> And sometimes that target will not allow bitrates
[01:17:51 CET] <infinmed> etc
[01:17:54 CET] <infinmed> I know it's insane
[01:17:56 CET] <infinmed> Although it is
[01:18:40 CET] <c_14> I can try condensing your command line into something reasonable if you tell me exactly what you're trying to accomplish
[01:18:55 CET] <infinmed> I already have
[01:18:56 CET] <infinmed> So no thanks but thanks
[01:19:13 CET] <infinmed> I'll tell you in a minute what it was I needed if you want
[01:25:20 CET] <infinmed> yeh I just need to set the dar
[01:25:22 CET] <infinmed> like the first person said
[01:25:42 CET] <infinmed> 19:12 < furq> infinmed: i think you want -vf setdar
[01:25:43 CET] <infinmed> absolutely correct thanks
[01:25:45 CET] <infinmed> Take it easy
[01:25:57 CET] <infinmed> I'll idle a few minutes
[01:36:08 CET] <infinmed> I'm kind of confused, because i can't pad to 720 if the video is larger, to add letterboxes, so ... ffmpeg errors.. and if fi scale first then there is nothing to pad
[01:37:50 CET] <kepstin> you're trying to turn a 16:9 video into a letterboxed 4:3 video?
[01:38:17 CET] <infinmed> https://ffmpeg.org/pipermail/ffmpeg-user/2011-July/001746.html this is what i'm looking at
[01:38:17 CET] <infinmed> no
[01:38:24 CET] <infinmed> things that are higher aspect ratio
[01:38:25 CET] <infinmed> to 16:9
[01:38:53 CET] <Tsutsukakushi> when converting avi to webm what options should i use so that the colours don't get completely ruined?
[01:38:58 CET] <furq> can you not just setdar=21/9 or whatever
[01:39:27 CET] <infinmed> I can try if you think that'll end up different than 16:9
[01:39:37 CET] <furq> i mean without adding black bars
[01:39:55 CET] <infinmed> no becuase ntsc dvd format is purely either 4:3 or 16:9 i mean you could
[01:40:00 CET] <infinmed> most dvd players would play it
[01:40:01 CET] <infinmed> although.. yeh
[01:40:19 CET] <kepstin> if you know the input video is always 16:9 or wider, simply doing -vf "scale=1280:-2,pad=1280:720:0:(oh-ih)/2" would be enough.
[01:40:25 CET] <kepstin> assuming you want 720p output
[01:40:25 CET] <infinmed> That link i posted has it i had based myself from that anyways i'll just look at things again
[01:40:53 CET] <infinmed> well i'm ready to accept that point since there is not many 4:3 videos i make
[01:41:35 CET] <kepstin> (that also assumes the input has square pixels, it gets more complicated if that's not the case)
[01:41:37 CET] <infinmed> Those two commands in the link i pointed out
[01:41:44 CET] <infinmed> I think one is just if it's less than 16:9 and more than 16:9
[01:42:08 CET] <infinmed> two commands so, all is well
[01:42:08 CET] <infinmed> I could script it if i was that lazy
[01:42:35 CET] <infinmed> "scale=iw*sar:ih , crop=min(iw\,ih*(16/9)):ow/(16/9)" -aspect 16:9
[01:42:40 CET] <infinmed> I know although I can just take out *sar
[01:42:48 CET] <kepstin> hmm? the second-last filter chain shown in that post should work on any input video size
[01:43:11 CET] <infinmed> I imagine or a yeh I mean yeh
[01:43:45 CET] <kepstin> if you want a specific output size it would be a bit more tricky, probably easiest to add another scale at the end.
[01:46:23 CET] <infinmed> perfect
[01:46:25 CET] <infinmed> perfect kepstin
[01:47:21 CET] <infinmed> It aspects correct and dvdauthor has no warnings at all
[01:47:21 CET] <infinmed> ffmpeg -i "$1" -y -c:v mpeg2video -c:a ac3 -b:v 4250k -b:a 384k -async 1 -threads 6 -mbd rd -trellis 2 -cmp 2 -subcmp 2 -timecode 01:02:03.04 -r 30000/1001 -filter:v "scale=1280:-2,pad=1280:720:0:(oh-ih)/2,setdar=16:9" -subq 2 -qcomp 0.7 -bf 2 -pass 1 -y -f dvd movie.mpg
[01:47:21 CET] <infinmed> ffmpeg -i "$1" -y -c:v mpeg2video -c:a ac3 -b:v 4250k -b:a 384k -async 1 -threads 6 -mbd rd -trellis 2 -cmp 2 -subcmp 2 -timecode 01:02:03.04 -r 30000/1001 -filter:v "scale=1280:-2,pad=1280:720:0:(oh-ih)/2,setdar=16:9" -subq 8 -qcomp 0.7 -bf 2 -pass 2 -y -f dvd movie.mpg
[01:48:48 CET] <kepstin> in that case, the -f dvd is doing the equivalent of adding an additional scale=720:480 (if ntsc, i forget if it's ntsc or pal by default...) at the end, among other things.
[01:49:09 CET] <infinmed> Well i tried without that and had vobu issues iwth dvdauthor in the past
[01:49:10 CET] <infinmed> let me try
[01:49:16 CET] <infinmed> it's just a format for the file
[01:49:20 CET] <infinmed> afaik
[01:49:26 CET] <kepstin> hmm, or right
[01:49:54 CET] <kepstin> if this is for a dvd, the video will have to be scaled to either ntsc or pal SD resolution for authoring, of course.
[01:50:05 CET] <infinmed> yes that's what your command accomplished for me
[01:50:14 CET] <infinmed> 16:9 which is as wide as dvd5 ntsc supports
[01:50:19 CET] <infinmed> err ntsc even
[01:50:34 CET] <cbsrobot-> 16:9 and 4:3 ist the aspect
[01:50:45 CET] <cbsrobot-> resolution is somthing like 720x576
[01:50:50 CET] <infinmed> it's the dar
[01:50:53 CET] <infinmed> display aspect ratio
[01:51:07 CET] <infinmed> not of the viewable area that's the par
[01:51:10 CET] <kepstin> yeah, ntsc supports 720x480 either stretched horizontally to 16:9 or squished horizontally to 4:3
[01:51:12 CET] <infinmed> Althoguh that's irrelevant
[01:51:23 CET] <kepstin> (it's more complicated than that, but that's close enough)
[01:51:40 CET] <cbsrobot-> if you want to burn your file to DVD this is not irrelevant
[01:51:52 CET] <infinmed> Trust me it is, the dar is the same as -aspect 16:9
[01:52:05 CET] <infinmed> It jsut sets the number without attempting to modify anything
[01:52:57 CET] <infinmed> ask flux
[01:52:58 CET] <infinmed> =]
[01:53:05 CET] <kepstin> -aspect 16:9 on an ntsc dvd isn't quite correct, since there's a border in the image size that's not part of the displayed image that you have to account for. But I think if you're storing in a vob/mpg container, it'll get rounded to the correct value
[01:53:15 CET] <infinmed> That's why i just wanted dto set the number
[01:53:16 CET] <infinmed> for the format
[01:53:20 CET] <infinmed> and crop it relatively
[01:53:22 CET] <infinmed> which is exactly what it does
[01:53:34 CET] <infinmed> with your crop command or the one on the link i posted
[01:54:50 CET] <kepstin> in general, the crop and scale filters in ffmpeg preserve the sample aspect ratio (sar), which is equivalent to adjusting the display aspect ratio (dar) in such a way that there's no stretch/squish distortion.
[01:55:12 CET] <kepstin> (or in the case of some scale operations, they adjust the sar if needed)
[01:56:02 CET] <infinmed> ^^ well there is always that, and that could be an issue, although afaik anything made in the last years would have the same sar, isn't it static for all hd display
[01:56:14 CET] <infinmed> It was just different on CRT neh?
[01:56:16 CET] <kepstin> all modern hd video uses a sar of 1:1, yeah
[01:56:21 CET] <infinmed> right
[01:56:34 CET] <kepstin> aka square pixels. it's just the old sd ntsc/pal stuff that's annoying to deal with
[01:56:54 CET] <infinmed> Exactly
[01:57:09 CET] <infinmed> Not too worried about it unless I want to convert it either way
[01:57:39 CET] <infinmed> All and all this is more proper then?
[01:57:40 CET] <infinmed> "scale=iw*sar:ih , pad=max(iw\,ih*(16/9)):ow/(16/9):(ow-iw)/2:(oh-ih)/2"
[01:57:40 CET] <infinmed> -aspect 16:9
[01:58:28 CET] <kepstin> generally accepted values for ntsc video, with a visible image area of ~704x480 within a 720x480 size is 10:11 for 4:3, or 40:33 for 16:9
[01:58:56 CET] <infinmed> Well that will scale it into 1:1 from what I am let know
[01:59:04 CET] <infinmed> Either way so, aught I wory about it
[01:59:44 CET] <infinmed> Thanks for the help
[01:59:52 CET] <kepstin> but yeah, in general taking a sar 1:1 aspect ratio 16x9 video and doing a "scale=720x480" will be "close enough" for ntsc dvd
[02:00:05 CET] <kepstin> it'll be slightly stretched horizontally, but not noticably.
[02:00:32 CET] <infinmed> =]
[02:02:14 CET] <infinmed> I'm thinking it was just the irreletivity I took from the crop commands
[02:02:17 CET] <infinmed> Later all =]
[02:26:31 CET] <jje_> fflogger: fyi... I just figured out why my output wasn't real 60fps all the way through...   I hadn't defined the rate for the 'color' generator.   r=60 worked :)
[02:26:39 CET] <jje_> have a great weekend all!
[05:16:11 CET] <pinPoint> is aac now out of strict experimental?
[05:16:21 CET] <pinPoint> libaac I think its called
[05:17:07 CET] <furq> it depends which aac encoder you use
[05:17:35 CET] <furq> afaik the native ffmpeg one is still experimental, but that one's not very good anyway
[05:32:33 CET] <c_14> furq: It's actually not bad these days.
[05:32:38 CET] <c_14> There's been a lot of work on it lately.
[05:32:54 CET] <c_14> It should get the experimental flag removed whenever the next few patches get finished.
[05:32:57 CET] <pinPoint> furq: the experimental is really good
[05:33:08 CET] <pinPoint> I've played with it just wasn't sure it fell out of experi. mode
[05:33:22 CET] <c_14> pinPoint: afaik not yet. soon"
[05:33:27 CET] <pinPoint> that includes, youtube videos, flac files, etc
[05:33:38 CET] <pinPoint> c_14: I was sure it was coming out like last month or two
[05:33:49 CET] <pinPoint> c_14: thanks
[05:33:59 CET] <c_14> The people working on it got busy
[05:35:46 CET] <c_14> pinPoint: https://trac.ffmpeg.org/ticket/2686 in case you're interested
[05:39:00 CET] <pinPoint> ah
[05:46:53 CET] <pinPoint> interesting... 8weeks ago "the edge of our seats" never got pushed/committed.
[10:14:35 CET] <jonascj> I have several sets of images I try to convert into a single timelapse including some title frames. My idea was to create a few individual videos and concat them.
[10:14:56 CET] <waressearcher2> jonascj: hallo
[10:15:12 CET] <jonascj> For the concat to work I need to .ts video from the images. is "ffmpeg -i %d.jpg -r 10 out.ts" enough?
[10:15:33 CET] <jonascj> Or should I have some format options in there?
[10:16:24 CET] <jonascj> waressearcher2: hello
[10:17:13 CET] <jonascj> -f mpegts maybe
[10:42:01 CET] <jonascj> directly to ts (ffmpeg -i %d.jpg -r 24 -f mpegts part.ts) followed by concat and encoding to x264 (ffmpeg -i "concat:part1.ts|part2.ts" -c:v libx264 out.mp4) looked horrible.
[10:42:11 CET] <jonascj> Maybe I have to tune the x264 quality parameters
[10:59:27 CET] <Keshl> jonascj: On the second one, try this: -c:v libx264 -preset medium -crf 23 -movflags faststart -pix_fmt yuv420p out.mp4
[11:00:23 CET] <jonascj> Thanks, I will. But actually I found that the original .ts results looked horrible
[11:00:36 CET] <Keshl> Well, that'll do it too.. XD
[11:01:43 CET] <jonascj> So I have to find a way to improove the original TS results, or do jpg -> mp4 -> ts -> mp4
[11:02:22 CET] <jonascj> or multiply the title frames and do everything in one go
[11:02:30 CET] <Keshl> For kicks, try doing what I said anyway but from the first TS, and use -crf 0 . It'll be lossless then, and /then/ convert to TS and see if it looks clean.
[11:02:46 CET] <Keshl> If it doesn't after that, it's TSs fault somehow and you should probably be looking at those parameters. oÉo.
[11:05:11 CET] <jonascj> The originals are just jpg images which look good. So it is the jpg->ts that screws things up. Would you try the your suggestion with mp4 first, then to ts and then to mp4 again? (jpg -> mp4 with your preset -> ts -> concat to mp4?
[11:05:49 CET] <Keshl> I'd give it a shot since I'm not great with ffmpeg and it might magically fix stuff with me having no clue why, but I'm fairly sure that nobody else would. XD
[11:06:08 CET] <Keshl> You should probably just read TS' parameters. Maybe they're absurdely low-quality by default.
[11:07:11 CET] <jonascj> Thanks, I'll try some things
[11:07:40 CET] <Keshl> Tell me if'ya get it workin'! I has a similar issue! OÉO Okay, well, I just wanna cat videos together. Still. -É-.
[11:32:01 CET] <gentwo_> i am trying to compile ffmpgeg for my server, debian.. following installation guide from here https://trac.ffmpeg.org/wiki/CompilationGuide/Ubuntu
[11:32:25 CET] <gentwo_> stuck on ffmpeg after CD to fffmpeg.. can some one give me help please
[11:33:01 CET] <gentwo_> the PATH="HOME/bin ..... doesn't do anything,, how can i proceed with that steps?
[11:39:23 CET] <gentwo_> my mistake.. i should have been ignored all those "\" lines... my bad...
[11:39:53 CET] <jonascj> :)
[11:39:54 CET] <gentwo_> libavcodec/dvdsubdec.c:321:17: warning: conversion lacks getting during the compile..
[11:40:09 CET] <gentwo_> i guess that just a normal warning...
[11:47:59 CET] <gentwo_> and i wonder why need yasm!!
[11:56:13 CET] <durandal_170> gentwo_: for less cpu cycles and faster execution
[12:11:12 CET] <gentwo_> i have only one user in the server..
[12:11:35 CET] <gentwo_> i guess its installed in the /root/bin/ffmpeg .. some reason my drupal don't detect .. :( sign
[12:11:53 CET] <fritsch> i really hope your drupal does not access /root directory ...
[12:12:03 CET] <fritsch> and even reads from it
[12:12:17 CET] <gentwo_> ouch!!
[12:12:49 CET] <gentwo_> fritsch: what are the options..
[12:13:10 CET] <fritsch> get some professional webserver support ...
[12:13:45 CET] <fritsch> running a webside as root user and accessing root's files ... disqualifies you from managing any server
[12:14:23 CET] <gentwo_> :(
[12:14:49 CET] <fritsch> and now back to scratchboard ...
[12:15:17 CET] <gentwo_> but drupal doesn't access any of this.. it access only /var/www folder
[12:15:41 CET] <gentwo_> is that i have to move ffmpeg in that folder!!? i don't understand...
[12:15:57 CET] <fritsch> no further comment ... if you run your webserver software as root users - i won't help you with a single bit ...
[12:17:06 CET] <gentwo_> fritsch: my webserver has single user , thats just root..// but the appache2 allows only /var/www.. and user can only access the public files.. which will be upload..
[12:17:43 CET] <gentwo_> fritsch: give me some hint.. i will follow that...
[12:17:52 CET] <gentwo_> just new to this, 2 weeks only...
[12:18:45 CET] <fritsch> you use gentoo?
[12:19:02 CET] <gentwo_> yes.. but not that extensive..low knowledge..
[12:19:12 CET] <fritsch> then please use a distro you can manage
[12:19:20 CET] <gentwo_> :D
[12:19:30 CET] <fritsch> this is for sure not the gentoo beginner's channel
[12:19:51 CET] <gentwo_> fritsch: but my webserver is running with debian.. not gentoo.
[12:20:11 CET] <gentwo_> i have no issues with gentoo. thats fine..
[12:20:41 CET] <waressearcher2> aber warum nichts CentOS ?
[12:41:51 CET] <rls> hi
[12:42:10 CET] <rls> is it possible to replace nginx-rtmp with ffserver?
[12:42:55 CET] <rls> I want to be fetching an udp stream and restreaming it locally as rtmp
[12:44:02 CET] <waressearcher2> rls: hallo
[12:44:14 CET] <rls> hi
[12:44:24 CET] <waressearcher2> rls: wie geht's ?
[12:44:45 CET] <rls> waressearcher2: I'm fine, thanks:)
[13:20:32 CET] <gentwo_> ok.. i have installed now a user.. not any more root..
[13:20:36 CET] <gentwo_> fritsch: ^
[13:20:58 CET] <fritsch> on debian the www server runs as www-data
[13:21:00 CET] <fritsch> automatically
[13:21:06 CET] <gentwo_> yes..
[13:21:11 CET] <fritsch> so it never run as root
[13:21:33 CET] <gentwo_> so i have a bin directory under new user home folder.. will that do?
[13:24:49 CET] <gentwo_> fritsch: so my earlier option was not bad at all.. users won't be able to access...
[13:24:57 CET] <gentwo_> fritsch: correct me if i am wrong..
[13:25:25 CET] <fritsch> nope
[13:25:41 CET] <fritsch> you need to distinguish between path the www server should access for serving
[13:25:50 CET] <fritsch> and paths it should uses for internal configuration
[13:25:57 CET] <gentwo_> fritsch: please give me some example and educate me...
[13:26:30 CET] <gentwo_> so my option with user having a bin in home folder containing ffmpeg is bad idea?
[13:26:42 CET] <fritsch> who / what will execute ffmpeg binary?
[13:26:49 CET] <gentwo_> drupal
[13:27:05 CET] <gentwo_> in other words www-data
[13:27:28 CET] <fritsch> 2.8.3-Jarvis-beta3 <- you did that?
[13:27:31 CET] <fritsch> wargh
[13:27:35 CET] <fritsch> https://www.drupal.org/node/422306
[13:27:39 CET] <fritsch> most likely you did - right? :-)
[13:28:07 CET] <fritsch> then "just" configure it accordingly
[13:28:29 CET] <fritsch> if it does not work, check that the ffmpeg bin is executable by "the rest"
[13:28:34 CET] <fritsch> e.g. has chmod +rx
[13:28:42 CET] <shevy> I have two input files, foobar.jpg and foobar.mp3
[13:28:57 CET] <shevy> I try to attach the image, to the .mp3, into a new .mp4 so that the .mp4 just will display that static image
[13:29:07 CET] <gentwo_> fritsch: thank you..
[13:29:17 CET] <gentwo_> fritsch: sir
[13:29:20 CET] <shevy> I was trying to follow some website which says to use something like this here:
[13:29:23 CET] <shevy>   ffmpeg -loop 1 -i foobar.jpg -i foobar.mp3 -c:v libx264 -c:a -strict experimental -b:a 192k -shortest output.mp4
[13:29:41 CET] <shevy> However, my ffmpeg 2.8.3 says "Unable to find a suitable output format for 'experimental'"
[13:30:03 CET] <shevy> is that perhaps a deprecated option?
[13:36:14 CET] <JEEB> that's because you were setting an audio encoder (-c:a) and when it expected an encoder name the argument you gave it was "-strict" (which is not an encoder AFAICS) and the next argument was taken as the output file name
[13:37:02 CET] <JEEB> there is no output container ("format") implicit for 'experimental' (since it has no extension)
[13:37:21 CET] <JEEB> basically you most probably wanted "-c:a aac -strict experimental" :P
[13:38:21 CET] <JEEB> (also you definitely want to update your FFmpeg to current master since IIRC the vast AAC encoder improvements for the internal encoder are not in 2.8.x)
[13:51:44 CET] <kepstin> even in 2.8.x it should be better than vo-aacenv, at least.
[13:51:53 CET] <shevy> JEEB I see
[13:52:14 CET] <JEEB> kepstin: true
[14:38:51 CET] <gentwo_> ffmpeg faststart where can i fidn it?
[14:39:10 CET] <durandal_170> in docs
[14:40:37 CET] <gentwo_> hmmm.. i need to install seperate!!  i don't understand..
[14:41:40 CET] <durandal_170> its option if you are creating new files
[14:42:25 CET] <durandal_170> And utility in tools for already existing files
[15:38:39 CET] <rls> I'm having issues routing an udp stream with ffmpeg to ffserver as flv
[15:39:05 CET] <rls> I get an accepted connection (200) at ffserver and just after that I get Conversion failed! at ffmpeg?
[15:39:34 CET] <Ripmind-> Is it possible to convert an iso file with ffmpeg?
[15:39:42 CET] <rls> no
[15:39:45 CET] <BtbN> Use nginx-rtmp if you need an rtmp server.
[15:39:50 CET] <Ripmind-> and the contents of it?
[15:39:54 CET] <Ripmind-> when i mount the iso?
[15:40:01 CET] <rls> BtbN: that seems to keep f-ing its buffers after every 12 seconds
[15:40:09 CET] <BtbN> Works for me.
[15:40:09 CET] <rls> Ripmind-: then yes
[15:40:23 CET] <BtbN> You did set the worker count to 1?
[15:40:24 CET] <Ripmind-> do i just do ffmpeg -i <pathtomount> ?
[15:40:54 CET] <rls> BtbN: I don't understand why it does it, but I'm fetching an UDP stream and sending it to nginx-rtmp and when I play through VLC it looses audio buffers after 12s of streaming
[15:41:07 CET] <rls> Ripmind-: you need output settings as well
[15:41:17 CET] <BtbN> That's just VLC. Its rtmp support is broken.
[15:41:29 CET] <rls> what to use to see if it works alright?
[15:41:33 CET] <rls> videojs?
[15:41:40 CET] <Ripmind-> "ffmpeg -i F: -c:v nvenc guardians.mkv" that's my command :(
[15:41:41 CET] <BtbN> ffplay, mpv, MPC-HC, ...
[15:41:44 CET] <Ripmind-> but i get permission denied
[15:41:44 CET] <BtbN> so, basicaly everything else.
[15:42:13 CET] <rls> BtbN: ffplay seems to play it with choppy fps for some reason
[15:42:29 CET] <BtbN> I'd guess your stream is broken in some way then.
[15:42:39 CET] <rls> the udp stream is correct
[15:43:25 CET] <rls> and the only conversion I'm doing is from aac-lc to aac with -bsf:a aac_adtstoasc
[15:43:34 CET] <rls> so I can fit an mpegts in the flv container
[15:43:59 CET] <BtbN> That's not changing it from lc to something else though. It just changes where the extradata is stored.
[15:44:02 CET] <Ripmind-> so, can ffmpeg convert a bluray disk to mkv?
[15:44:16 CET] <rls> Ripmind-: it should be able to
[15:44:19 CET] <Ripmind-> humm
[15:44:27 CET] <BtbN> Propably not, as blurays are filled with DRM as much as humanly possible.
[15:44:49 CET] <BtbN> And even if it could, pointing it to some directory won't do anything usefull
[15:44:57 CET] <Ripmind-> i always get permission denied
[15:46:04 CET] <c_14> Ripmind-: you have to build with libbluray, and then hope said bluray isn't encrypted
[15:46:20 CET] <Ripmind-> c_14: it's not in by default?
[15:46:34 CET] <c_14> No
[15:46:46 CET] <c_14> And then you have to use the bluray protocol
[15:46:47 CET] <BtbN> It's legaly questionable I guess, so you'll have to build it yourself.
[15:46:48 CET] <Ripmind-> how lucky i am that i already have my buld env. for ffmpeg :)
[15:48:23 CET] <c_14> libbluray shouldn't be questionable since it doesn't do any DRM circumvention, libaacs on the other hand would depend on where you live (though since it doesn't include any actual keys it should be fine as well)
[15:51:37 CET] <gentwo_> http://pastebin.com/35vn6mzF  getting an error while encoding.. please give me some hint
[15:52:55 CET] <c_14> [libx264 @ 0x1d621a0] constant rate-factor is incompatible with 2pass.
[15:53:19 CET] <c_14> And [libx264 @ 0x1d621a0] -qscale is ignored, -crf is recommended.
[15:53:27 CET] <gentwo_> hmm, i am using some preset.. is that a reason..
[15:53:48 CET] <c_14> Do you want a constant bitrate or do you want "constant quality"?
[15:54:34 CET] <gentwo_> i don't mind variable bit rate.. its for a website. aiming for mobile users only..
[15:54:47 CET] <c_14> Then don't use 2-pass, and get rid of the -qscale
[15:55:12 CET] <c_14> You might also want to set an audio bitrate
[15:55:30 CET] <c_14> Not sure what the default is, but it's probably low
[15:57:03 CET] <kepstin> that stream doesn't even have any audio anyways...
[15:57:10 CET] <gentwo_> c_14: i can't find those option in the configuarion of drupal video modules.. may be something i have to setup manually..
[15:57:13 CET] <gentwo_> no idea
[16:20:57 CET] <gentwo_> i wish i can get a good preset code..
[16:21:10 CET] <gentwo_> any suggestion.. seems the preset i am using is very bad..
[16:21:21 CET] <gentwo_> c_14: any thoughts please..
[16:21:36 CET] <c_14> I have no idea what those drupal video modules are
[16:22:23 CET] <c_14> I can help you with an ffmpeg commandline, but that's about it.
[16:22:53 CET] <gentwo_> c_14: i am exporting my current preset .. it contains all the stuff./. may be you could give me a hint..
[16:23:25 CET] <gentwo_> c_14: http://pastebin.com/4uaGtR60
[16:24:03 CET] <gentwo_> for sure i am doing something wrong again as usual
[16:32:42 CET] <gentwo_> c_14: i did it,,, wghooooooooooooooooooooooaaaaaaaaaaaaa
[16:32:46 CET] <gentwo_> thanks guys
[16:32:47 CET] <gentwo_> :D
[16:36:16 CET] <gentwo_> avi passed well.. but failed on mov
[16:36:21 CET] <gentwo_> c_14: http://pastebin.com/FzaqA5nJ
[16:36:36 CET] <gentwo_> error opening filters .. what does that mean
[16:50:20 CET] <c_14> ffmpeg doesn't have a qdmc decoder
[17:04:10 CET] <Franciman> Hello
[17:04:48 CET] <Franciman> I want to use ffmpeg APIs from C, where can I find their documentation?
[17:05:06 CET] <Franciman> and maybe some tutorial too
[17:05:48 CET] <fritsch> https://ffmpeg.org/doxygen/trunk/api-example_8c-source.html Franciman
[17:06:07 CET] <Franciman> oh great, thanks
[17:06:43 CET] <fritsch> https://github.com/FFmpeg/FFmpeg/tree/master/doc/examples <- there are some more
[17:07:33 CET] <Franciman> thanks fritsch
[17:24:31 CET] <rls> hi
[17:24:43 CET] <rls> is it possible to embed ffplay in QT or some other GUI?
[17:26:40 CET] <JEEB> ffplay is not a proper video player
[17:26:56 CET] <JEEB> look at libmpv/libvlc for actual video player embedding
[17:27:04 CET] <JEEB> both should have Qt embedding examples
[17:27:26 CET] <JEEB> unless you really meant QT and not Qt :P
[17:27:48 CET] <rls> well, I've never written GUIs on python, just installet PyQt4
[17:27:58 CET] <JEEB> ok, so you meant Qt
[17:27:59 CET] <rls> and wanted to use ffmpeg's libraries to embed a couple of video feeds in a gui
[17:28:06 CET] <JEEB> ffplay is not a library
[17:28:40 CET] <JEEB> anyways, if you need an actual *player* (which uses actual libav* libs in the background), then libmpv and libvlc are the things you want to be looking at
[17:29:14 CET] <rls> nice, thanks
[17:30:04 CET] <rls> which one is supposed to be better?
[17:30:42 CET] <Franciman> Hey, if I am extracting audio from a video, how can I determine whether the current AVPacket contains just one frame or more than one?
[17:30:45 CET] <JEEB> libmpv has a much better renderer (opengl / opengl els with ANGLE for windows), libvlc is probably more mature at this point
[17:30:51 CET] <JEEB> *opengl es
[17:31:08 CET] <JEEB> you can check the Qt examples for both
[17:33:49 CET] <rls> JEEB: thanks, I'll try how that could be done in PyQt:)
[17:41:14 CET] <rls> JEEB: am I supposed to install libvlc for python via pip?
[17:41:57 CET] <JEEB> lolwut
[17:42:29 CET] <rls> not sure how to get the lib
[17:42:59 CET] <JEEB> build it or download a binary for your OS/distro?
[17:43:08 CET] <JEEB> also if you want to use libvlc, goto #videolan
[17:46:43 CET] <rls> didn't realise the obvious fact that VLC has libvlc:)
[18:20:34 CET] <Ripmind-> the bitrate when i execute ffmpeg, is this the encoding bitrate or the bitrate the video file will have at the end?
[18:26:50 CET] <DHE> ffmpeg displays the bitrate of the file at the end
[18:48:53 CET] <Ripmind-> How do i set a better quality?
[18:49:02 CET] <Ripmind-> the option -crf doesn't exist for me
[18:49:07 CET] <c_14> what codec?
[18:51:13 CET] <Ripmind-> It's the nvenc
[18:51:30 CET] <Ripmind-> i fouznd -vb and set it to 50M, should that be good?
[18:52:29 CET] <c_14> 50M is pretty high, haven't tested at what point nvenc starts producing decent quality though
[18:52:54 CET] <Ripmind-> it need spretty big bitrates from what i heared
[18:53:03 CET] <Ripmind-> Also, how can i select the audio stream?
[18:53:18 CET] <Ripmind-> I want Stream #0:2, not #0:1
[18:53:27 CET] <c_14> use map?
[18:53:34 CET] <Ripmind-> Ok, i'll cresearch that
[18:53:35 CET] <Ripmind-> thanks
[19:01:24 CET] <Ripmind-> [dca @ 0000004d88f4fba0] Overread auxiliary data by 32 bits <- can this be somethign bad?
[19:01:30 CET] <Ripmind-> Error while decoding stream #0:2: Invalid data found when processing input
[19:02:04 CET] <c_14> Either means the input bitstream is invalid or there's a bug somewhere.
[19:07:10 CET] <Ripmind-> it came up 6 times now
[19:28:17 CET] <Prelude_Zzzzz> hey everyone, what is the best filter to smooth edges .. i am using some low bit rates and i see a lot of pixel issues on the edges
[20:16:52 CET] <kepstin> Prelude_Zzzzz: do you want to filter the video before encoding in the hopes of reducing the appearance of issues, or filter after decoding to hide the issues?
[20:17:24 CET] <ffmpegstarter> Hello, I am trying to capture video and audio from a Cam (/dev/video1) and ac:1 and write it to a file output.mp4. Using the command http://pastebin.com/xYRamzMG but the output video plays the video very fast first and then the audio plays in a normal speed. How can I sync both of them and get atleast 25fps currently at ~10
[20:17:39 CET] <jrm> I'm trying to make a screencast using this: http://ftfl.ca/paste/screencast.html.  It's working, but the colour is off.  Everything is quite a bit duller.  I can post screenshots and a short clip if it's helpful.
[20:17:53 CET] <kepstin> the only sort of pre-filtering that would help is a blur to reduce the high-frequency content of the picture.
[20:17:56 CET] <Prelude_Zzzzz> the encoding actually
[20:18:09 CET] <Prelude_Zzzzz> i just see the rough edges on the output
[20:18:12 CET] <Prelude_Zzzzz> another crazy thing is...
[20:19:03 CET] <Prelude_Zzzzz> http://pastebin.com/8Dh2rLX7
[20:19:10 CET] <Prelude_Zzzzz> that is super more important and i have been at it for hours
[22:27:41 CET] <Putti> Hi! Can I have screen capture video to be outputted as raw file with ffmpeg (no h264 encoding etc. happening)? At the moment i'm using the following command to do the capturing: "ffmpeg -video_size 3840x2160 -framerate 30 -f x11grab -i :0.0 -vcodec libx264 -r 30 -qp 0 -preset ultrafast output.mkv". But the CPU usage is high so I'm wondering if the encoding process could be done afterwards..
[22:28:47 CET] <JEEB> yeah, you can use things like ffv1, ffvhuff or utvideo instead. all of which are lossless altogether (so no need for the -qp/q)
[22:31:52 CET] <Putti> JEEB, ok. So they're lossless but does ffmpeg need to do some conversion from it's internal binary representation to output with for example ffv1? Or is ffv1 used internally?
[22:32:24 CET] <JEEB> of course there is some sort of compression done because raw RGB or YCbCr is just a *lot* of data
[22:33:52 CET] <JEEB> you can output raw video to nut I guess if you really want to
[22:34:12 CET] <Putti> Oh, I want to try it ! :D
[22:34:23 CET] <JEEB> (nut is a container I've pretty much only seen used with raw video and audio together with timestamps and the type of raw video it is)
[22:34:24 CET] <Putti> How should I change my command=
[22:34:33 CET] <JEEB> but really, try one of the faster lossless coders first
[22:34:53 CET] <JEEB> if those are still too slow, start checking if it's really the encoding that's slowing you down, or something before that
[22:35:00 CET] <Putti> My command looks like this now: ffmpeg -video_size 3840x2160 -framerate 30 -f x11grab -i :0.0 -vcodec ffv1 -r 30 -preset ultrafast output.mkv . Does it look alright?
[22:35:02 CET] <JEEB> such as the action of screen capture itself
[22:35:27 CET] <JEEB> skip the -r after input unless you want to convert it to something else than the input
[22:35:35 CET] <JEEB> also ffv1 has no presets
[22:35:39 CET] <JEEB> otherwise looks good
[22:35:54 CET] <JEEB> also ffv1 might be one of the slower ones out of those three
[22:36:05 CET] <JEEB> ffvhuff might be the fastest
[22:36:35 CET] <c_14> Last time I checked ffv1 had the best speed/compression ratio.
[22:36:46 CET] <JEEB> yeah, but if speed is the only thing mentioned here
[22:37:05 CET] <JEEB> he has 2160p content there as far as I can tell, so I guess the main idea is to be "fast enough"
[22:37:42 CET] <Putti> yeah
[22:37:45 CET] <JEEB> but if both ffvhuff and ffv1 are slow, then it's just a case of welp, and you will have to check if it's as slow encoding from raw data on a ramdisk or so
[22:37:59 CET] <JEEB> thus, making sure that your capture part isn't making it slow
[22:38:09 CET] <JEEB> rather than whatever is happening afterwards
[22:38:22 CET] <c_14> If you only care about speed, zlib should be the fastest.
[22:38:22 CET] <Putti> ffv1 looks like it's working fast but the fps which it uses is 9
[22:38:35 CET] <Putti> in which file format should the output be=
[22:38:36 CET] <Putti> ?
[22:38:47 CET] <c_14> matroska
[22:39:10 CET] <c_14> I think only ffmpeg will eat that though
[22:39:28 CET] <JEEB> oh right, zlib is around too
[22:39:39 CET] <JEEB> I guess that's exactly what the name implies
[22:39:48 CET] <JEEB> and threading is made with frame threads at the same time
[22:40:53 CET] <Putti> It's not outputting any file: "ffmpeg -video_size 3840x2160 -framerate 30 -f x11grab -i :0.0 -vcodec ffv1 -r 30 -f matroska output" what might be wrong?
[22:41:20 CET] <JEEB> full terminal output please, in a pastebin
[22:41:36 CET] <JEEB> also as I said, don't have -r after -i since you already have -framerate before -i
[22:41:44 CET] <JEEB> you are doing unnecessary possible changes with that
[22:41:51 CET] <JEEB> or well, processing
[22:41:55 CET] <Putti> Oh! It worked on the second time
[22:41:59 CET] <JEEB> in the best case it's a no-op
[22:42:05 CET] <Putti> Okay!
[22:42:08 CET] <JEEB> in the worst case you are getting crappy frame rate conversion there
[22:42:15 CET] <JEEB> so no need for it there
[22:42:16 CET] <JEEB> :P
[22:43:06 CET] <Putti> Looks like the cpu usage is still pretty high with ffv1
[22:44:42 CET] <Putti> I'll try the other ones, or how did I use the nut thing?
[22:45:00 CET] <c_14> -f nut
[22:45:08 CET] <furq> Putti: if you're going to be encoding this anyway you might want to try using x264 non-lossless
[22:45:12 CET] <JEEB> just try ffvhuff , zlib, utvideo first
[22:45:13 CET] <furq> it should be faster than x264 lossless
[22:45:35 CET] <JEEB> I think the idea was to create a proper well-compressed copy afterwards :P
[22:45:39 CET] <JEEB> without the realtime requirement
[22:45:41 CET] <Putti> yes!
[22:46:09 CET] <furq> i'm inferring from "I'm wondering if the encoding process could be done afterwards.."
[22:46:09 CET] <Putti> exactly, I don't have any need to stream it right away to somewhere etc.
[22:47:08 CET] <Putti> So my goal is basically just to have the screen capture working with as low cpu usage as possible and with 30fps
[22:47:33 CET] <JEEB> also you could take a look at the capture speed with `ffmpeg -video_size 3840x2160 -framerate 30 -f x11grab -i :0.0 -f null -`
[22:47:37 CET] <JEEB> that's a benchmark of sorts
[22:48:05 CET] <furq> Putti: my point is that -qp 0 will probably have higher cpu usage than -crf 23 or whatever lossy setting
[22:48:10 CET] <JEEB> "capture stuff and just pass the stuff that would be fed to encoders to the void"
[22:48:24 CET] <Putti> JEEB, that gives exactly 30 fps
[22:48:33 CET] <JEEB> ok
[22:49:06 CET] <JEEB> `ffmpeg -video_size 3840x2160 -framerate 30 -f x11grab -i :0.0 -c:v rawvideo -f nut welp.nut`
[22:49:10 CET] <JEEB> this is the raw video thing
[22:49:34 CET] <JEEB> (this actually does funky things when the input is compressed IIRC)
[22:49:54 CET] <JEEB> (because rawvideo can also mean "input, as-is")
[22:50:16 CET] <Putti> Does it matter that it says 8.7 fps with that raw command?
[22:50:42 CET] <JEEB> most probably IO limited
[22:50:47 CET] <JEEB> iotop time :P
[22:52:08 CET] <JEEB> also you probably want to not compress audio
[22:52:25 CET] <JEEB> although I'm not sure if you have audio with that
[22:52:26 CET] <Putti> Well I don't care whether there is audio or not
[22:53:00 CET] <JEEB> yeah, I guess you would have to have pulse or alsa input in there to have audio
[22:53:31 CET] <furq> Putti: bear in mind that 4k rawvideo is going to be about 350MB/sec
[22:54:50 CET] <JEEB> which is why I noted that it's most probably the IO
[22:54:53 CET] <Putti> iotop shows 300MB disk write
[22:55:15 CET] <Putti> so I guess I need a raid of ssds :P
[22:55:37 CET] <JEEB> try out ffvhuff, zlib as well
[22:55:56 CET] <Putti> I will
[22:55:58 CET] <JEEB> and yeah, this is why you have light lossless compression :P
[22:56:34 CET] <Putti> I think there will be 10GBs of data after few minutes of recording :D
[22:56:50 CET] <furq> there'll be 20GB after one minute
[22:57:58 CET] <Putti> wow! Hey, with ffvhuff what do I set as a file type?
[22:59:40 CET] <furq> mkv
[23:01:59 CET] <Putti> Okay. Is there somewhere documentation about which file types can be used with different encoders? for ffv1 I found but not for ffvhuff
[23:03:27 CET] <JEEB> in general unless a muxer complains that it can't put format X into container Y it shouldn't be an issue
[23:03:56 CET] <JEEB> I would probably recommend nut for raw or some very specific video formats due to the fact that the timestamps are stored better there than in matroska
[23:04:05 CET] <JEEB> although I think for 30fps matroska should be fine, too
[23:04:16 CET] <JEEB> matroska murders 24000/1001 for example
[23:04:42 CET] <JEEB> (due to the imprecision of its timebase capabilities)
[23:06:14 CET] <Putti> ffvhuff did 20 fps for me. But I have seen that it does it for any encoder if I put as an extension .mkv
[23:06:37 CET] <JEEB> container shouldn't matter :P
[23:06:47 CET] <JEEB> unless that muxer is very badly written
[23:07:02 CET] <JEEB> and so far I don't remember any that would be like that
[23:08:03 CET] <Putti> with mp4 and h264 I got that 30 fps but then the cpu usage was so high
[23:08:11 CET] <furq> Putti: i take it you have a good reason for not downscaling
[23:08:59 CET] <Putti> furq, by downscaling you mean lowering the resolution?
[23:09:03 CET] <furq> yes
[23:09:10 CET] <furq> even 1440p should be more than twice as fast
[23:11:38 CET] <Putti> Actually I'm just testing which settings would make the lowest cpu usage. But I want to record 1080p but so that my whole screen would be there.. but when I put the video size as 1920x1080 it didn't capture the whole screen.
[23:12:09 CET] <furq> -video_size 3840x2160 -i :0.0 -vf scale=1920:1080
[23:13:09 CET] <Putti> Ok haha, but now the fps dropped by 10
[23:13:38 CET] <Putti> So that might be useful after recording :)
[23:16:02 CET] <Putti> but I guess I need to forget 4k recording now until I might get an ssd raid :P
[23:16:22 CET] <Putti> and plenty of space on them
[23:19:34 CET] <Putti> Thank you everyone for helping me! :)
[23:48:16 CET] <Putti> Is Intel QuickSync Video acceleration in ffmpeg already? I see in the documentation under -hwaccel that it should be but ./configure doesn't show it as an option.
[23:49:09 CET] <JEEB> I think it uses libmxf as its back-end, so I think ./configure --help might show it as such
[23:49:23 CET] <JEEB> that said, just keep in mind that it will do not so well compressed lossy only
[23:49:37 CET] <JEEB> nvidia has support for lossless 4:2:0 and 4:4:4, funny enough
[23:49:44 CET] <Putti> --list-hwaccels showed it :)
[23:49:57 CET] <Putti> Okay, good to know!
[00:00:00 CET] --- Sun Nov 29 2015



More information about the Ffmpeg-devel-irc mailing list