[Ffmpeg-devel-irc] ffmpeg.log.20140727

burek burek021 at gmail.com
Mon Jul 28 02:05:01 CEST 2014


[00:01] <FrEaKmAn_> I have no idea
[00:28] <LanDi> anyone know how to record my mic on a skype conversation ?
[03:39] <YaMoonSun> It's such a pain when even wording the question is a hard.. How do I make the perfect DVD rip? I've got a 1.3GB .mp4 that's flawless (seemingly) and a 3.4GB .mkv (exact copy) / Should I preserve the mpeg2/ac3, or go with x264/aac? I'm trying to save space without losing quality.
[03:40] <sacarasc> How much time do you want to put into it?
[03:40] <sacarasc> (Both learning and encoding.)
[03:42] <YaMoonSun> I have unlimited of both
[03:42] <YaMoonSun> Like seriously
[03:43] <YaMoonSun> I had to duel-boot Mint to get a terminal so I could actually use ffmpeg - cmd was being a bitch
[03:44] <sacarasc> Ah, because I was going to recommend mostly Windows tools. :D
[03:44] <YaMoonSun> I'm on Windows 7 right now, but unless there's another version of cmd I can ingegrate I may have to swap over, cause I can't scroll up to read all of the command help
[03:49] <sacarasc> The basics, though, ffmpeg -i input.mkv -c:a copy -c:v libx264 -crf 18 -preset:v veryslow output.mkv
[03:49] Action: sacarasc is a little distracted at the moment, sorry.
[03:50] <c_14> https://trac.ffmpeg.org/wiki/Encode/H.264
[03:50] <c_14> I'd personally keep the audio in AC3, but if you want AAC: https://trac.ffmpeg.org/wiki/Encode/AAC
[03:51] <sacarasc> For a perfect rip, I'd not use ffmpeg.
[03:51] <c_14> I think he has a rip and wants to make it smaller.
[03:51] <c_14> If I read the question correctly.
[03:51] <sacarasc> The latter one sounds like it was just a remux.
[03:52] <c_14> Is a remux not a rip?
[03:53] <sacarasc> I suppose so.
[03:56] <YaMoonSun> Esstentially I want to copy the codecs from the .mkv and just reduce the bitrate to make a smaller file size (hopefully without fucking up the quality)
[03:57] <klaxa> i suggest trial and error
[03:57] <YaMoonSun> You've seen a YIFI rip? I want that quality/size from a DVD rip. His Spirited Away rip had like 4 lanaguges and it wasn't even 600mb
[03:58] <klaxa> and reading stuff
[03:58] <Hello71> lel yify
[03:58] <Hello71> 1. you didn't spell it right.
[03:58] <sacarasc> You say perfect, then say them...
[03:58] <Hello71> 2. they encode audio at like aac 80 kb/s
[03:58] <klaxa> i only heard bad things about yify so i avoid them
[03:58] <Hello71> although spelling it like that is what I would expect
[03:59] <Hello71> their rips aren't bad per se, just low quality
[03:59] <klaxa> i guess doom9 and doom10 forums are the right places to look for information on dvd encoding
[03:59] <Hello71> everyone on the public trackers is like v10 a10
[04:00] <sacarasc> And they're banned on most private trackers. \o/
[04:00] <sacarasc> I mean, I don't know.
[04:01] <YaMoonSun> I mean, the .mp4 I produced, I was satisfied with at first. I just feel like I can reduce the video bitrate somehow without losing too much quality, and then swap the aac to ac3 and maybe save a tad bit more room even then. I heard it's better to encode using divx for DVDs as they use mpeg2, but I have no idea if I'll get the same quality as a x264
[04:02] <klaxa> x264 will give the best quality at the lowest filesize for now
[04:03] <c_14> If you _really_ want the smallest file you can, (and you want mp4) encode the audio to AAC at the lowest bitrate you can stand and then try a 2-pass x264 and target the filesize you want.
[04:04] <sacarasc> And use -preset:v veryslow or maybe placebo, to get the last bits of quality you can from it at the bit rate.
[04:05] <c_14> And use recent versions of x264 and ffmpeg (preferably git head or the latest release).
[04:05] <c_14> And libfdk_aac, but all that stuff should be on the wiki pages I linked before.
[04:06] <sacarasc> You'd probably want to compile yourself to get libfdk_aac.
[04:15] <YaMoonSun> Let's say I I'm open to more container options so long as I can keep the audio quality - The original is 224kbps ac3, and my .mp4 is 300+ kbps (nearly twice the size)
[04:16] <c_14> Matroska can handle ac3 so you can copy the audio stream, that'll give you the identical audio quality as in the original file but will not compress it (more than it already is anyway).
[04:16] <klaxa> try opus
[04:16] Action: klaxa ducks
[04:16] <c_14> Opus has admirable quality at low and very low bitrates.
[04:18] <YaMoonSun> I have an .mkv of it too, but the video stream is ridiculous in it... Can I just take the .ac3 codec and use it to replace the .aac codec in the .mp4?
[04:19] <klaxa> yes
[04:19] <c_14> IIRC mp4 does not support AC3 audio.
[04:19] <c_14> klaxa: Does mp4 support ac3?
[04:19] <klaxa> uh... dunno
[04:19] <YaMoonSun> Not much room saved, but a start. Then.. idk.. a mpeg2 being encoded into an mpeg2 to be put into the .mp4 should be smaller than the original presumably, right?
[04:19] <klaxa> wikipedia says yes
[04:20] <klaxa> wh-what?
[04:20] <klaxa> you want to re-encode mpeg2 to mpeg2?
[04:20] <klaxa> you're bound to lose quality
[04:20] <klaxa> also h264 offers a lot more quality for less bitrate
[04:21] <klaxa> mpeg2 is so 1996
[04:21] <YaMoonSun> You've tried this, or read this? I mean, I presume the encoding will take less time, and take up less space, but yeah, may be very well wrong.
[04:22] <c_14> There is a reason that mpeg2 has been superseded as a codec.
[04:22] <klaxa> if you don't give a damn about compatibility and only care about storage place and don't even want to watch the movie, try h265
[04:23] <c_14> H.264 is the current jack-of-all-trades allround decent codec.
[04:23] <klaxa> s/place/space
[04:23] <klaxa> it's late
[04:25] <Hello71> ffmpeg -c:a libmp3lame -f wav mp3.wav
[04:25] <klaxa> wat
[04:25] <YaMoonSun> How do you predetermine the audio quality of a DVD without making an .mkv? Just open in VLC or something?
[04:25] <Hello71> "predetermine the audio quality"
[04:25] <Hello71> ???
[04:25] <klaxa> what do you mean? determine the audio quality?
[04:25] <c_14> Open it in something that can print bitrates. (as much as a bitrate can tell you about audio quality notwithstanding)
[04:26] <YaMoonSun> The kbps and Hz rate
[04:26] <Hello71> Hz rate.
[04:26] <YaMoonSun> inb4 -,-
[04:26] <klaxa> you can use ffprobe for example
[04:26] <Hello71> sure, if that's what you want to call it.
[04:27] <YaMoonSun> Sexy, never heard of it - Looking into it now.
[04:27] <klaxa> but depending on the encode, high bitrate and high sampling rate may not reflect what you want to know
[04:28] <YaMoonSun> Give me an article as to why so you don't have to waste you time explaining it? Sounds like it would take more than a sentence.
[04:28] <klaxa> because maybe the person encoding was incompetent
[04:28] <klaxa> quality is a subjective measurement
[04:28] <klaxa> listen to audio, watch a video
[04:28] <c_14> subjectivity \o/
[04:29] <klaxa> that's how you determine quality
[04:30] <YaMoonSun> I'm giving myself a headache. I had an arguement, but I foresaw your reply, and I'm already in checkmate, so yeah. If I reencode a ac3 to ac3 I will be losing more quality, no? So just use audio copy to get the exact version..
[04:31] <klaxa> basically every non-lossless encode will always lose quality
[04:31] <klaxa> that's why they are called lossy
[04:32] <klaxa> if you want to reduce the filesize re-encoding is fine, but be aware that you will lose quality
[04:32] <klaxa> it may be so little that you can't tell the difference, then that's a good trade-off
[04:33] <YaMoonSun> So if I rip a 320kbps 41kHz .mp3 from a .flac and then keep reencode it to .mp3 again, and make another .mp3 from it's copy, and continue that process, eventually I'll have nothing?
[04:33] <klaxa> you will eventually have noise
[04:34] <c_14> White noise iirc.
[04:35] <YaMoonSun> Ac3 encoding vs ac3 passthrough? The passthrough is lossless? (As lossless as it's going to get)
[04:36] <c_14> Passthrough should be not reencode but just copy. (but it might depend on the program and how they define things)
[04:37] <YaMoonSun> Much appreciated; All of you. Even the sarcasm, lol - I'm going to go try a few things and I'll let you know the outcome. (Cause I'm sure you care ;) )
[04:37] <YaMoonSun> Ttyl, and thanks again.
[05:30] <ac_slater> hey all. Looking through libavformat's sources for mpeg2ts, I cant figure out if it's possible to ADD an arbitrary stream as a separate stream with a different program ID (PID).
[06:45] <onyx> Hey guys, Im running this cron job that records a live stream for 5 mins in the hours of 5am till 7pm
[06:45] <onyx> * 5-19 * * * /usr/local/bin/ffmpeg -i http://serverip/live -acodec copy -vcodec copy -t 5:00 /destination-folder/ -$(date +\%d-\%H).mp4 > /dev/null 2>&1
[06:45] <onyx> is working great
[06:45] <onyx> how do I go about creating thumbnails for those videos?
[06:47] <sacarasc> Add something like (I will probably mess this up, so be prepared to work on it) this after the .mp4: -ss 2:30 -vframes 1 /destination-folder/ -$(date +\%d-\).png
[06:48] <onyx> ok
[06:55] <onyx> shouldnt be -ss 00:02:30.000
[06:55] <onyx> ?
[06:55] <onyx> acording to this https://trac.ffmpeg.org/wiki/Create%20a%20thumbnail%20image%20every%20X%20seconds%20of%20the%20video
[07:04] <sacarasc> Shouldn't your -t be similar, then? ;p
[07:05] <onyx> idk
[07:05] <onyx> LOL
[07:05] <onyx> trying now...
[07:07] <onyx> nope it didnt work
[07:13] <onyx> Unable to find a suitable output format for 'vframes'
[07:13] <onyx> vframes: Invalid argument
[07:13] <onyx> omg... I forgot the "-"
[07:13] <onyx> LOL
[11:22] <FrEaKmAn_> wow.. when cutting the file, the parameters order is important
[11:22] <FrEaKmAn_> can someone explain why?
[11:35] <Mavrik> the parameter order is always important.
[11:44] <FrEaKmAn_> didn't know
[11:44] <FrEaKmAn_> because the different in my situation was that video/audio were out of sync
[12:37] <jnvsor> Do x264 presets do anything if I'm specifying the bitrate manually and not using a crf?
[12:37] <JEEB> yes
[12:37] <JEEB> presets do not affect rate control
[12:37] <JEEB> they just set the speed vs compression
[12:38] <jnvsor> Allrighty, thanks!
[15:04] <jeffreylevesque> i just installed ubuntu 14.04 (was using 11.04).  ffmpeg is no longer available in apt-get.  SHould i get a PPA, what's going on here
[15:07] <JEEB> jeffreylevesque, debian/ubuntu switched to Libav, you can get a similar tool to current FFmpeg with avconv (since FFmpeg merged the command line changes it's similar in usage except for some FFmpeg-only features)
[15:08] <JEEB> if that one doesn't work, you can either grab some static FFmpeg builds or compile it yourself
[15:08] <jeffreylevesque> JEEB, are conversion times the same?  S
[15:10] <jeffreylevesque> sorry got disconnected
[15:10] <JEEB> jeffreylevesque, yes
[15:11] <JEEB> conversion times are mostly controlled by the encoder, and thus it's more dependant on libx264 than FFmpeg/Libav
[15:11] <JEEB> as an example
[15:11] <jeffreylevesque> JEEB, do you recommend ffmpeg, or avconv?
[15:12] <JEEB> there shouldn't be a large difference unless something you need is only in FFmpeg
[15:13] <JEEB> and given that you came from 11.04 I guess you don't at least right now have any needs regarding that
[15:13] <JEEB> you'll have to get used to the new command line stuff that elenril made anyways, and that's in both
[15:14] <JEEB> in case you happen to end up needing an ffmpeg binary, then you can always either grab one of the static builds, or build one yourself
[15:14] <JEEB> (since f.ex. the best AAC encoder right now can't be distributed in binary form as it's not compatible with GPL, and some of the encoder libraries are GPL)
[15:14] <jeffreylevesque> thank you
[15:28] <khali> hi there
[15:28] <sfan5> hello
[15:30] <khali> ffprobe incorrectly reports MPEG Layer 2 audio streams as "mp3"
[15:30] <khali> I think it used to be correct, I don't know when it broke exactly
[15:31] <sfan5> I'd suggest reporting a bug at the bug tracker
[15:33] <khali> sfan5: yes, I'll do that
[15:42] <FrEaKmAn_> I'm trying to concat 2 files (http://pastie.org/private/tuonakgfbsteyqrwvh8rg)
[15:42] <FrEaKmAn_> but the video is totallly distorted
[15:42] <FrEaKmAn_> the only difference I see is video size
[15:42] <FrEaKmAn_> could this be a problem?
[15:43] <khali> FrEaKmAn_: definitely
[15:43] <khali> you just can't concatenate videos with different frame sizes
[15:43] <khali> you'll have to scale one of them first, using -vf scale
[15:45] <FrEaKmAn_> ok
[15:53] <FrEaKmAn_> khali: yup
[15:53] <FrEaKmAn_> works now
[15:54] <FrEaKmAn_> just when I concat the video, scale gets changed
[15:58] <khali> FrEaKmAn_: in which way?
[15:59] <FrEaKmAn_> it's squeezed
[15:59] <FrEaKmAn_> I think one of my videos is strange
[16:24] <khali> FrEaKmAn_: size is one thing, DAR is another
[16:24] <khali> both must match
[16:48] <FrEaKmAn_> I solved it
[16:49] <FrEaKmAn_> but what is DAR?
[17:01] <c_14> Display Aspect Ratio
[17:11] <FrEaKmAn_> ow
[17:12] <FrEaKmAn_> I'm using scale='if(gt(a,16/9),1280,-1)':'if(gt(a,16/9),-1,720)'
[17:12] <FrEaKmAn_> as described here https://trac.ffmpeg.org/wiki/Scaling%20(resizing)%20with%20ffmpeg
[17:12] <FrEaKmAn_> if I define 1280/720 it works
[17:12] <FrEaKmAn_> but if I define 640/360 it doesnt
[17:20] <FrEaKmAn_> ideas?
[17:22] <c_14> Not really, you want to scale the video down to 640x360 while keeping aspect ratio so that you can concat, right?
[17:23] <c_14> You might need to add a pad filter after that scale.
[17:24] <FrEaKmAn_> c_14: yes
[17:24] <FrEaKmAn_> and all videos need to have aspect ratio
[17:27] <c_14> You said that it's not working. What 'it' exactly? The scaling or the concat after the scale?
[17:28] <FrEaKmAn_> the video is gray
[17:28] <c_14> The video resulting from the scale?
[17:28] <FrEaKmAn_> with few color pixels
[17:28] <FrEaKmAn_> concat
[17:28] <c_14> ffprobe the video that was outputted from the scale
[17:28] <c_14> The aspect ratio might be off
[17:29] <FrEaKmAn_> one second
[17:37] <FrEaKmAn_> c_14: sorry.. I guess I was concatenating wrong files
[17:37] <FrEaKmAn_> seems to work now with 640x360
[17:37] <FrEaKmAn_> feeling excited until next problem
[18:08] <FrEaKmAn_> well then I try to scale video with 1280x718 to 640x360 I get Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height
[18:08] <FrEaKmAn_> ideas?
[18:08] <FrEaKmAn_> but to scale to 1280x720 it works great
[18:09] <c_14> You're using x264?
[18:09] <FrEaKmAn_> c_14: yes
[18:10] <c_14> What could be happening is that the scale from 1280x718 to 640x360 is giving you an odd height, H.264 doesn't like that, but paste your command and output like sacarasc said and we can check.
[18:10] <FrEaKmAn_> one second
[18:12] <ersatzbeardr> hey is ffmpeg the right tool to place a series of pngs (with transparency) over various time signatures in a mpeg4 file, should i just produce blank frames for the ones i don't need or what
[18:17] <FrEaKmAn_> c_14: http://pastie.org/9424883
[18:17] <FrEaKmAn_> it's true [libx264 @ 0x33b0120] height not divisible by 2 (640x359)
[18:18] <maslen1> Could anyone point me to a sample MKV file that includes Cues ?
[18:18] <FrEaKmAn_> must I use pad? to upscale video?
[18:19] <c_14> You can either pad to make it even, or add a short round to your scale.
[18:21] <c_14> scale="trunc(iw/2)*2:trunc(ih/2)*2" will make sure both height and width are even numbers
[18:26] <FrEaKmAn_> c_14: but I want to scale it to 640x360
[18:26] <FrEaKmAn_> so I have to do 2 runs or can change my code scale="'if(gt(a,16/9),640,-1)':'if(gt(a,16/9),-1,360)'"
[18:27] <c_14> You can replace iw with (if(gt(a,16/9),620,-1 and analog with ih
[18:27] <c_14> Just set the parenthesis corretly.
[18:28] <FrEaKmAn_> ok
[18:28] <FrEaKmAn_> lets me try
[18:36] <FrEaKmAn_> c_14: we are getting close
[18:36] <FrEaKmAn_> http://pastie.org/9424911
[18:37] <FrEaKmAn_> but the output video has incorrect scale
[18:37] <FrEaKmAn_> 640x718
[18:37] <FrEaKmAn_> 718 did not change
[18:40] <c_14> ah, eh: trunc(-1/2)*2 = 0
[18:40] <c_14> ...
[18:41] <FrEaKmAn_> yes
[18:41] <c_14> New plan
[18:42] <c_14> scale="'if(foobar):if(barfoo)'",scale='trunc(iw/2)*2:trunc(ih/2)*2"
[18:42] <c_14> That should work.
[18:42] <c_14> Hopefully.
[18:42] <FrEaKmAn_> foobar?
[18:42] <c_14> foobar is that whole if(gt(a,..... expression
[18:43] <c_14> I didn't feel like typing it.
[18:43] <FrEaKmAn_> ok
[18:47] <FrEaKmAn_> c_14: it produces 640x358
[18:48] <FrEaKmAn_> I think I need to pad and then scale
[18:48] <c_14> Either pad and then scale or scale and then pad.
[18:48] <FrEaKmAn_> can I put pad in same command?
[18:49] <c_14> ye
[18:50] <FrEaKmAn_> I have this scale="'if(gt(a,16/9),640,-1)':'if(gt(a,16/9),-1,360)',scale='trunc(iw/2)*2':'trunc(ih/2)*2',pad=width=640:height=360:x=0:y=0:color=black"
[18:50] <FrEaKmAn_> any good tricks to center the video?
[18:51] <c_14> x=(ow-iw)/2:y=(oh-ih)/2
[18:52] <c_14> And if you're padding to an even height/width then you can get rid of the second scale.
[18:52] <c_14> Since all that ensures is that it's even.
[18:52] <FrEaKmAn_> ok
[18:55] <FrEaKmAn_> seems ok
[18:55] <FrEaKmAn_> ffprobe reports right scale
[19:12] <onyx> so yesterday cron didnt work
[19:13] <onyx> is there a command to create thumnails for all the files in the folder that dont have thumbnails?
[19:13] <FrEaKmAn_> c_14: thanks for your help!
[19:16] <c_14> np
[19:16] <c_14> onyx: That looks like the job of a bash script and some scaling.
[19:20] <Nitori> does "ffmpegsource" have anything to do with ffmpeg?
[19:20] <ersatzbeardr> actually maybe i was going about this wrong, can i use ffmpeg to add an mpeg as an alpha to another mpeg then composit it with a third mpeg
[19:20] <ersatzbeardr> i'm trying to get one video over another video with the alpha coming from somewhere else
[19:24] <Nitori> (nevermind)
[22:15] <sythe> "Failed to open bitstream filter aac_adtstoasc for stream 0 with codec copy: Not yet implemented in FFmpeg, patches welcome"
[22:15] <sythe> :(
[22:16] <sythe> Hmm
[22:16] <sythe> I'll try combining the mp3 of the file with the video
[22:34] <sythe> Hey rcombs
[22:34] <sythe> I'm trying to append a video to another
[22:35] <sythe> But it has an AAC audio track
[22:35] <sythe> How can I remove the AAC track?  (so I can replace it with an mp3 track)
[22:36] <sfan5> try using -map
[22:36] <sythe> sfan5: Can you elaborate?
[22:37] <Hello71> the unixy way is to do -c:a none - | ffmpeg -i - -i input.mp3
[22:37] <sfan5> use -map to only use the inputs that are not the aac track
[22:37] <sfan5> do you use -f concat?
[22:37] <sythe> Yeah
[22:38] <sfan5> what error message do you get?
[22:39] <sythe> Scroll up
[22:39] <sfan5> ah
[22:39] <sythe> It combines it, but all the audio is gone
[22:39] <sfan5> did you try first removing the aac track of the first video?
[22:40] <sythe> The video doesn't have an AAC track
[22:40] <sythe> The first one, that is
[22:40] <sythe> The second one does
[22:40] <sfan5> did you try first removing the aac track of the second video?
[22:42] <sythe> I don't know how to do that
[22:42] <sythe> " <sythe> How can I remove the AAC track?  "
[22:43] <sythe> sfan5: ^
[22:43] <relaxed> -map the streams you want in the output
[22:43] <sfan5> ^
[22:44] <sfan5> e.g. if there are 3 streams (some video, some audio and aac) you want to do ffmpeg -i input.mp4 -map 0:0 -map 0:1 -c copy output.mp4
[22:44] <relaxed> sythe: https://trac.ffmpeg.org/wiki/How%20to%20use%20-map%20option
[22:45] <trn> In case anyone cares, I was able to fix my problem, but it required a source patch.
[22:46] <relaxed> how can that guide not include an example with multiple inputs :/
[22:46] <sfan5> developers usually don't like to document stuff
[22:47] <trn> I added a -force-ts-discont command which adds AVFMT_TS_DISCONT to .flags in AVInputFormat.
[22:47] <relaxed> reading the docs on the new website makes me want to claw my eyes out.
[22:47] <sfan5> you probably want to send that patch to ffmpeg-dev
[22:48] <trn> sfan5: It's sort of a hack, I'm not sure it's the appropriate solution, but it works in my case.
[22:48] <trn> Also I switched from using NUT internal container format to pass streams around inside the application to using FFM2.
[22:49] <sythe> relaxed: How do I list the streams of a file?
[22:49] <sfan5> sythe: either ffmpeg -i file or ffprobe file
[22:50] <sythe> thanks
[22:50] <relaxed> sythe: read -->  man ffmpeg-all | less +/'   -map'
[22:50] <llogan> relaxed: i would have preferred a white or at least a light background
[22:50] <trn> sfan5: I just noticed this on the mailing list... http://lists.ffmpeg.org/pipermail/ffmpeg-devel/2014-June/158513.html
[22:51] <trn> sfan5: It essentially does the exact same thing in the exact same scenario as what I did, except I added a flag to turn the flag on for whatever format.
[22:52] <sythe> I don't see the AAC stream listed
[22:52] <trn> Because technically that "live_flv" is just an abuse of flv just like my use of FFM/NUT transport in segments is sort of an abuse as well.
[22:52] <sfan5> maybe it's in the other file?
[22:52] <trn> But it doesn't make sense to create a totally new transport container format just for my application.
[22:53] <trn> sfan5: You think I should still send it?
[22:53] <relaxed> llogan: What was the motivation for the change? I thought the old style was fine.
[22:54] <llogan> i don't know. i guess people thought it was too 2004.
[22:55] <sfan5> trn: I don't think it's needed if there is already a patch that does it differently
[22:55] <sythe> Hey
[22:55] <sythe> How do I concatenate and mix two files?
[22:55] <trn> sfan5: That patch only does it for FLV, but I need it for NUT and/or FFM.
[22:55] <sythe> When I add a video file to another
[22:55] <sythe> Both with MP3 streams
[22:56] <trn> sythe: concat filter, etc.
[22:56] <sythe> And both h.264 mp4s
[22:56] <sythe> The audio is lost
[22:56] <sythe> Well, it appears in the stream list
[22:56] <sythe> But it's not there
[22:56] <sfan5> trn: in that case it would make sense to send it
[22:56] <llogan> sythe: show "ffmpeg -i input0 -i input1 -i input2" etc if you're using concat demuxer and also...
[22:57] <sythe> ffmpeg -i "concat:intermediate1.ts|intermediate2.ts" -c copy -bsf:a aac_adtstoasc episode4-upload.mp4
[22:57] <llogan> use the demuxer
[22:57] <sythe> IDK what that is
[22:57] <trn> OK, will do when I get to work on Monday.
[22:57] <sfan5> sythe: https://trac.ffmpeg.org/wiki/How%20to%20concatenate%20(join,%20merge)%20media%20files
[22:57] <llogan> https://trac.ffmpeg.org/wiki/How%20to%20concatenate%20%28join,%20merge%29%20media%20files#demuxer
[22:58] <sythe> llogan: Extract the audio?
[22:59] <llogan> ffmpeg -i input -c:a copy ouput
[23:01] <sythe> I'll use that script
[23:01] <sythe> Looks good
[23:02] <llogan> i don't know what you're trying to do
[23:03] <sythe> Add another video file (with audio) to the end of one
[23:05] <trn> Also do you think the mailing list would want patches to work with older versions of some optional libraries?
[23:06] <trn> They aren't as clean but I can patch autoconf stuff for it if it's needed.
[23:06] <trn> Mainly because RHEL provides older versions with backported security and bug fixes and I wanted ffmpeg to work with the system libraries where it wasn't actually using functionality provided by the newer libraries.
[23:07] <sfan5> just send the patches and you'll notice soon enough if nobody wants/needs them
[23:07] <trn> OK, I don't want to be a PITA or nothing.
[23:09] <sfan5> asking in the -devel channel might also be an option
[23:09] <trn> Ah, will do.
[23:09] <trn> Thanks. :)
[23:28] <sythe> Ok, the script you guys linked...
[23:28] <sythe> Is taking AGES
[23:29] <sythe> Also, does FFMPEG do lossless conversion?
[23:29] <sythe> Since I saw something about FPS
[23:29] <sythe> And I don't want FFMPEG downscaling the FPS to 15
[23:40] <llogan> sythe: the concat demuxer will " Add another video file (with audio) to the end of one".
[23:40] <llogan> ffmpeg supports several lossless encoders
[23:42] <sythe> llogan: I didn't see anything about that on that link
[23:44] <sythe> llogan: Ok
[23:44] <sythe> Nvm
[23:44] <sythe> I see
[23:44] <sythe> I'll try it
[23:55] <sythe> llogan: It worked-ish
[23:55] <sythe> all the audio is there
[23:55] <sythe> The second video is just a gray screen
[23:56] <c_14> The 2 videos have to have the same codec.
[23:57] <sythe> Video: h264 (Constrained Baseline) and Video: h264 ([33][0][0][0] / 0x0021)
[23:57] <sythe> are those not the same, c_14 ?
[23:59] <c_14> I'm not versed in the hex representation of h264 profiles, but they look different to me.
[00:00] --- Mon Jul 28 2014


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