[Ffmpeg-devel-irc] ffmpeg.log.20140303

burek burek021 at gmail.com
Tue Mar 4 02:05:01 CET 2014


[02:04] <bparker> I've been looking at the quicktime file format spec on apple's website for like 30 minutes now, and I still can't figure out which atom the h264 NALU stream is stored in
[06:56] <Zeranoe> I'm trying to optimize x264 encoding for file size and quality. So far I have -crf 25 -preset veryslow -tune film, any suggestions?
[07:16] <bparker> void av_register_all() { static int initialized; if(initialzed) return; initialized = 1; ... }
[07:16] <bparker> uhh isn't that a bug since initialized is ... uninitialized?
[07:35] <Dark-knight> how do i convert .3gp to .mp4?
[07:35] <alteregoa> hi
[07:35] <alteregoa> i always get some spaghetti code when i try to compile ffmpeg with actual x264
[07:35] <alteregoa> bavcodec/libx264.c:616: Nicht definierter Verweis auf `x264_encoder_open_142
[07:38] <alteregoa> http://pastebin.com/8rGEnM1q
[07:42] <Zeranoe> Dark-knight: Pretty straight forward, x264, aac should be your encoders
[07:43] <Dark-knight> alight
[07:43] <Dark-knight> alright*
[08:06] <Dark-knight> the video already has mpeg4 should i go head and change it to x264?
[08:06] <Dark-knight> im not using it for any programs
[08:06] <Dark-knight> just viewing it
[08:06] <Dark-knight> Zeranoe
[08:14] <Zeranoe> Dark-knight: What is your goal? Why are you converting?
[08:14] <Dark-knight> just for my viewing pleasure
[08:15] <Zeranoe> why go from 3gp to mp4?
[08:15] <Dark-knight> because .3gp launches a different program and i can't view it on my tv
[08:16] <Zeranoe> can you ffprobe the 3gp file to find what streams your working with? you might be able to just copy them and remux into mp4. just run ffprobe -i input.3gp
[08:20] <Dark-knight> amr_nb is the audio stream
[08:20] <Dark-knight> video is mpeg4
[08:21] <Dark-knight> what is better for visual quality mpeg4 or x264?
[08:24] <Zeranoe> Well nothing is better than the original stream. Lossless would be to no advantage here. Try remuxing the streams into an avi. -c:v copy -c:a copy out.avi
[08:34] <Dark-knight> so just input.3gp -c copy out.avi
[08:35] <Zeranoe> -c:v copy -c:a copy
[08:40] <Dark-knight> -c copy does the same thing
[08:41] <Dark-knight> if there was more then 1 video or audio stream then i would do -c copy -map 0
[08:41] <llogan> Zeranoe: typical suggestion is to use the highest crf value that still looks good for you and to use the slowest preset you have patience for. some filtering may be useful depending on your content
[08:48] <Dark-knight> what generally has better sound quality, ac3 or aac?
[08:48] <Zeranoe> aac
[08:48] <llogan> you probably couldn't tell the difference with a decent encoder using a decent bitrate
[08:48] <llogan> and generally they are used for different things
[08:49] <Dark-knight> ok i copied the video codec and changed the audio to aac and it made the video 1 second longer
[08:49] <Dark-knight> why did i do wrong and how do i fix it?
[08:49] <Zeranoe> AAC for low bitrate and overall better compression for data
[08:49] <llogan> Dark-knight: according to what player?
[08:50] <Dark-knight> mediainfo
[08:50] <llogan> what does ffmpeg say?
[08:50] <Dark-knight> ill do it again
[08:50] <llogan> no, just do "ffmpeg -i yourfile.foo"
[08:50] <llogan> and then look at the duration
[08:50] <alteregoa> opus is great
[08:51] <Zeranoe> Good point, alteregoa
[08:51] <alteregoa> but unsupported at all by hw devices
[08:51] <Dark-knight> what audio encoder should i use to make it aac?
[08:52] <Zeranoe> Only a matter of time
[08:52] <Zeranoe> fdk-aac, if possiblwe
[08:52] <llogan> https://trac.ffmpeg.org/wiki/AACEncodingGuide
[08:52] <Zeranoe> See: http://trac.ffmpeg.org/wiki/AACEncodingGuide
[08:52] <Zeranoe> hm
[08:52] <Zeranoe> your too fast
[08:52] <llogan> on;y because i was too lazy to type "See:"
[08:52] <Zeranoe> lol
[08:53] <Dark-knight> which aac encoder is the best?
[08:53] <Zeranoe> fdk
[08:53] <Dark-knight> ok
[08:53] <Zeranoe> its not gpl though
[08:53] <Dark-knight> for some reason it says libfaac is not supported
[08:54] <llogan> did you configure with --enable-libfaac?
[08:54] <Zeranoe> it isnt included in the public builds, it is the best but that isnt what you were really asking now is it?
[08:54] <Dark-knight> no
[08:54] <Zeranoe> Best for the public is the internal aac
[08:55] <Dark-knight> what are the downside to using a non-GPL encoder?
[08:55] <alteregoa> Dark-knight, the chinese wall
[08:56] <alteregoa> because some western sofware companies can sue corps
[08:56] <llogan> you can't distribute it if it requires --enable-nonfree
[08:56] <Zeranoe> Well technically is is LGPL. And practically GPL other than the selling part...
[08:56] <llogan> libfdk-aac only requires --enable-nonfree if you include --enable-gpl, IIRC
[08:56] <alteregoa> llogan, you can but only in china
[08:57] <llogan> yes, they do whatever they want
[08:57] <alteregoa> thats good
[08:57] <alteregoa> because software patents sucks
[08:57] <Dark-knight> so then which encoder should i use because i want it to be compatible with everything
[08:57] <llogan> ...such as violating the FFmpeg license
[08:57] <Zeranoe> internal aac
[08:58] <Dark-knight> ok
[08:58] <Zeranoe> and there is nothing that is compatible with "everything"
[08:58] <Dark-knight> so just -c:a aac
[08:58] <llogan> any of them will create a compatible output
[08:58] <Zeranoe> read that AAC page
[08:58] <Dark-knight> i am
[08:59] <alteregoa> instead of using 10bit h264 for 4k resolution they use now some "new" h265 a completly different thing - just to hold the license fees
[08:59] <Zeranoe> "Native FFmpeg AAC encoder"
[08:59] <Zeranoe> There is more to 265 than that
[09:04] <Zeranoe> Debating if I want to downmix a 5.1 to 2 channel....
[09:05] <Dark-knight> ok when i convert it, it just makes a 0 kb file
[09:06] <Dark-knight> it says aac is an experimental codec that is disabled by default
[09:06] <Dark-knight> wtf
[09:07] <Zeranoe> Read the page...
[09:07] Action: andrew_46 read: -strict experimental ....
[09:08] <llogan> hi andrew_46
[09:08] <andrew_46> llogan: hi :)
[09:11] <andrew_46> Some great stuff on that wiki
[09:11] <Dark-knight> now it says incorrect bitrate when trying to use aac
[09:13] <Zeranoe> Does FFmpeg support downmixing from 5.1 to 2 well? I know there are some odd channel balance settings that lots of programs mess up
[09:13] <Dark-knight> no idea
[09:13] <llogan> one user recently reported that LFE was being omitted, but no samples or console output was provided
[09:13] <Zeranoe> Dark-knight: What command did you use?
[09:14] <Dark-knight> ffmpeg -i Scream_Dancing.3gp -c:v copy -strict -2 -c:a aac Scream1.mp4
[09:15] <Zeranoe> ffmpeg -i Scream_Dancing.3gp -c:v copy -strict -2 -c:a aac -b:a 128k Scream1.mp4 (assuming your working with 2 channel, you want 64k per channel)
[09:15] <Dark-knight> ok ya i saw that bit of the page
[09:16] <Dark-knight> but didn't think i had to do it with the native aac encoder
[09:16] <Zeranoe> llogan: Was that fixed?
[09:16] <llogan> i don't know if it is a bug or not, and I haven't attempted to duplicate the issue.
[09:16] <andrew_46> Dark-knight: what is the ausio in the 3gp file?
[09:16] <andrew_46> audio
[09:16] <Dark-knight> amr_nb is the audio stream
[09:19] <llogan> Zeranoe: looks like he just answered his own question regarding LFE http://superuser.com/questions/723731/downmix-drops-low-frequency-channel
[09:19] <Dark-knight> the console gives an this error
[09:19] <Dark-knight> [aac @ 000000000410ebc0] Too many bits per frame requested
[09:19] <Dark-knight> Error while opening encoder for output stream #0:1 - maybe incorrect parameters
[09:19] <Dark-knight> such as bit_rate, rate, width or height
[09:20] <Zeranoe> Woh, how is that a good idea
[09:20] <Dark-knight> ffs I type shit, then delete it and it looks my grammar sucks. I swear my grammar doesn't suck.
[09:21] <Zeranoe> relevant: http://trac.ffmpeg.org/wiki/AudioChannelManipulation
[09:22] <Zeranoe> i dont see 5.1>stereo though
[09:22] <llogan> you can add it if you like. that would be a good addition
[09:24] <Dark-knight> which once should i use for windows?
[09:24] <Dark-knight> http://trac.ffmpeg.org/wiki/CompilationGuide
[09:24] <llogan> just get a windows build from a guy names Zeranoe
[09:24] <llogan> *named
[09:24] <Dark-knight> i have his build already
[09:24] <Dark-knight> it doesn't include the encoders i need
[09:25] <Zeranoe> Dark-knight: You don't need fdk...
[09:25] <Dark-knight> ok
[09:25] <Dark-knight> then why won't it let me use native aac
[09:25] <Dark-knight> ?
[09:25] <Zeranoe> paste your output to pastebin, the full output that has the error
[09:26] <Zeranoe> llogan: There it is: http://www.ffmpeg.org/ffmpeg-filters.html#Mixing-examples
[09:26] <Zeranoe> Why -ac 2 doesn't assume that seems beyond me, but there probably was a rason
[09:26] <Zeranoe> reason*
[09:27] <Dark-knight> http://pastebin.com/gChgsK9N
[09:27] <Dark-knight> lol oops
[09:27] <Dark-knight> wait...
[09:27] <Dark-knight> nvm
[09:27] <Dark-knight> that is the output with the errpor
[09:27] <Dark-knight> error
[09:28] <Zeranoe> You didn't put -b:a 128k
[09:28] <Dark-knight> it gives that same problem
[09:29] <Zeranoe> then -ac 1 because it's mono
[09:29] <Dark-knight> http://pastebin.com/jjLjBiAF
[09:30] <Zeranoe> sorry, -b:a 64k
[09:30] <Zeranoe> that probably wont resolve it...
[09:30] <Dark-knight> nope it didn't
[09:30] <Dark-knight> same error
[09:31] <Dark-knight> same 0 KB file
[09:31] <llogan> lower your bitrate or increase your -ar
[09:31] <Dark-knight> ex?
[09:31] <llogan> -ar 44100
[09:31] <llogan> -b:a 32k
[09:32] <Zeranoe> Dark-knight: Try -b:a 32k
[09:32] <Zeranoe> danget
[09:32] <Dark-knight> just did
[09:32] <llogan> this encoder give this message on occassion
[09:33] <Dark-knight> it worked
[09:33] <Dark-knight> 32k worked
[09:33] <Dark-knight> why?
[09:33] <Zeranoe> Dark-knight: BTW, googling that error gave the solution in the first hit
[09:33] <Dark-knight> thank you for googling for me
[09:38] <Dark-knight> is -strict experimental the same as -strict -2
[09:40] <alteregoa> stil got some spastic errors with compiling it
[09:40] <alteregoa> x_264 encoderopen
[09:40] <llogan> Dark-knight: yes
[09:41] <Dark-knight> thx
[09:47] <Zeranoe> How is -map used for two inputs? I want to take just the video from the first input, the audio from the 2nd input, and mux them into one file
[09:48] <llogan> Zeranoe: -map 0:v -map 1:a
[09:49] <Zeranoe> llogan: Are those arguments position independent for the overall command?
[09:49] <llogan> it will take the video from the first input and the audio from the second input
[09:50] <llogan> i mean it will map the video input(s) from the first input and the audio input(s) from the second input
[09:50] <llogan> if you want the second video stream from the first input: -map 0:v:1 (remember that "0" is "first" in FFmpegese for map).
[09:51] <llogan> or you can simply use -map 0:0 for first input, first stream, but it has the disadvantage of no stream type selection
[09:53] <Zeranoe> It seems to be working, I was just wondering if they needed to be placed before the 2nd input, so something like ffmpeg -i first -map 0:v -i second -map 1:a, but I don't think so
[09:53] <llogan> ffmpeg -i input0 -i input1 -map 0:v -map 1:a output
[09:54] <llogan> since -map is an output option
[09:55] <Zeranoe> thanks,just double checking
[10:52] <amigojapan> Hi, I am trying to concatenate (join) many videos I made into one video, I tried the following ffmpeg command, but the result was a video with no audio, any ideas?
[10:52] <amigojapan> d:\ffmpeg\bin\ffmpeg.exe -i "concat:video_only.avi|output.avi|o2.avi" -c copy output_video.avi
[10:52] <amigojapan> This is the command output on the CLI http://pastebin.com/G5JEgAT6
[11:07] <alteregoa> i installed anything but ffmpeg still doesnt want to compile it
[11:09] <Dark-knight> what better 8000 Hz or 44.1 Hz?
[11:11] <alteregoa> 44.1
[11:11] <Dark-knight> thx
[11:11] <alteregoa> usual is 48KHz for video files
[11:11] <alteregoa> and 44.1 for audio
[11:12] <Dark-knight> ahh thats why the sound was so choppy
[11:12] <Dark-knight> it was at 8000 Hz
[11:12] <Dark-knight> i fixed it
[11:12] <alteregoa> 8KHZ hsa only 4KHz headroom, it sounds like telephone
[11:16] <alteregoa> not its time for a crappucino
[11:16] <Dark-knight> which is better
[11:16] <Dark-knight> English, 96.0 Kbps, 8 000 Hz, 16 bits, AC-3
[11:16] <Dark-knight> or
[11:16] <Dark-knight> English, 32.1 Kbps, 44.1 Hz, 2 channels, AAC (LC)
[11:16] <alteregoa> the 2nd
[11:16] <alteregoa> but...
[11:17] <Dark-knight> but the first has a higher kpbs
[11:17] <alteregoa> but only 8khz sample rate
[11:17] <Dark-knight> both sound the same
[11:18] <alteregoa> use the second anyway
[11:18] <alteregoa> its a bug maybe idk
[11:19] <Dark-knight> its no bug
[11:19] <Dark-knight> the first was made 5 hours ago
[11:19] <Dark-knight> the second was made 7 mins ago
[11:20] <alteregoa> ok
[11:20] <Dark-knight> so should i still use the second one?
[11:21] <alteregoa> if this 8000khz is true yes
[11:23] <amigojapan> is there some front end GUI for ffmpeg, which can help me understand hwo to construct the command I need?
[11:24] <amigojapan> I need to join several video files
[12:20] <alteregoa> darmok and jalad at tanagra
[12:21] <amigojapan> alteregoa: what movie was that? I forgot
[12:21] <amigojapan> star trek?
[12:21] <amigojapan> alteregoa: oh it is the episode with picard and the aliens
[12:24] <alteregoa> that was star trek tng
[12:24] <alteregoa> yeah with the tamarian dude, he couldn't understand any word
[12:25] <alteregoa> so the tamarians captured picard and a tamarian captain
[12:25] <alteregoa> i finaly get it to compile the holy stuff i hope
[12:25] <alteregoa> had to add --extra-libs=-ldl
[12:26] <alteregoa> maybe it means local dynamic library
[12:40] <amigojapan> alteregoa: yeah, I liked that episode a lot, eventhough I coudl no really understand everything.... I guess the universal translator was working for words, but not for that kind of metaphoric way of speaking, that confused me a lot when I saw it
[13:27] <amigojapan> OK, both ways of concatenating videos worked now, the problem was that one of the input videos had not audio track it seems.
[13:30] <Jack64> hey guys, quick question. I want to convert a regular MKV to a web-optimized MP4, keeping video intact (x264) but converting AC3 audio to libfdk_aac. Can anyone give me a good one liner for this? Thanks
[13:31] <Jack64> ahem, by regular, read 720p / 1080p files
[13:31] <JEEB> ffmpeg -i welp.mkv -c:v copy -c:a libfdk_aac -b:a XXXk -movflags +faststart out.mp4
[13:31] <JEEB> something like this :P
[13:32] <JEEB> the movflags option is the one most probably incorrect, since I almost never actually use it
[13:36] <DeadSix27> JEEB: i think it doesnt work anymore or i use it wrong, i tried -movflags with "+" and without.. we both discussed that once already
[13:36] <DeadSix27> but i usually just run qtfaststart manually after ffmpeg
[13:37] <DeadSix27> according to wiki: -movflags faststart Run a second pass moving the index (moov atom) to the beginning of the file. This operation can take a while, and will not work in various situations such as fragmented output, thus it is not enabled by default.
[13:38] <DeadSix27> they didnt use + there.
[13:38] <DeadSix27> i think the "+"  is just to combine multiple flags like in the example beyond it shows: -"movflags isml+frag_keyframe"
[13:39] <JEEB> probably, yeah
[13:39] <JEEB> I really don't use it :P
[13:39] <Jack64> hmm, the process I'm using now is really crappy, I use mkvextract to get the audio track, re-encode that, then remux them back together with MP4Box... there has to be an ffmpeg one liner for that
[13:40] <JEEB> Jack64, did you conveniently just ignore me?
[13:40] <JEEB> thank you very much
[13:40] <DeadSix27> haha
[13:40] <DeadSix27> well afk
[13:40] <Jack64> no I didn't eheh
[13:41] <Jack64> I gotta check that -movflags option then
[13:41] <Jack64> I had tried something like you said but without the movflags
[13:41] <Jack64> no playback in the browser
[13:42] <Jack64> it was actually EXACTLY the same as yours but without the movflags
[13:42] <Jack64> gonna check that out then, thanks
[13:42] <JEEB> that should in theory do the moving of the index to the beginning of the file
[13:42] <JEEB> automagically
[13:43] <Jack64> ok, gonna test it now
[13:43] <JEEB> having it on the back can be a problem for some things, in some cases it tries to cache the whole file, in other cases it tries to read it from the end of the file, and in some it just fails
[13:47] <Jack64> so far so good...
[13:47] <Jack64> no errors..
[13:53] <Jack64> aaaaaand it woooorks :D Thank you so much JEEB
[13:58] <Dark-knight> http://memedepot.com/uploads/0/453_club.jpg
[14:03] <alteregoa> Dark-knight, i prefer horse meat
[14:03] <Dark-knight> lol
[17:23] <Zeranoe> I ran a ivtc to take the source from interlaced 29.58 to 23.98. The audio wasn't stretched for this so they are out of sync when put together. Any way I could correct that?
[17:41] <JEEBsv> Zeranoe: uhh, why would audio have anything to do to it if you just IVTC o_O
[17:41] <JEEBsv> if you did a simple IVTC then the audio should still be 100% in synch
[17:41] <JEEBsv> if it isn't, you either did something in addition to that, or you failed at something
[17:44] <Zeranoe> JEEBsv: Doesnt the duration change after ivtc?
[17:44] <JEEBsv> no
[17:44] <JEEBsv> you remove pictures and change the timestamps
[17:50] <julienb> Hello
[17:51] <julienb> i contact you because i have a problem of global headers:0kB muxing overhead 0.79357 when i try to cut a video without rencoding
[17:53] <julienb> i put the pastbin here http://pastebin.com/MAV0XeVW
[18:11] <relaxed> julienb: what's the problem? your ffmpeg version is pretty old, by the way.
[18:11] <relaxed> also, that's not an error message
[18:23] <julienb> relaxed, i installed the last stable version for gentoo
[18:23] <julienb> there is not a particular problem video is good but there is this message at the end
[18:23] <julienb> video:57294kB audio:6847kB subtitle:0 global headers:0kB muxing overhead 0.759017%
[19:07] <relaxed> julienb: it's just an informative message
[19:09] <relaxed> Gentoo's notion of "stable" is wrong. The ffmpeg devs recommend using a recent build from git or at least the latest release, which is 2.1.4.
[19:35] <julienb> ok thanks relaxed
[22:08] <kg7fu-2> Hello
[22:08] <kg7fu-2> can someone help with %d spec for image sequence please?
[22:11] <sacarasc> Can you be more specific?
[22:12] <kg7fu-2> sure
[22:13] <kg7fu-2> ffmpeg -f image2 -i "r%03d.jpg"  -r 12 foo.av
[22:13] <kg7fu-2> 60+ images in directory. Have tried .png & .jpg's
[22:13] <kg7fu-2> r%03d.jpg: No such file or directory
[22:13] <kg7fu-2> and placing the % in various spots.
[22:14] <kg7fu-2>   Problem is cross-platform as I have it wit
[22:14] <sacarasc> What is the first image called?
[22:14] <kg7fu-2> ubuntu 13.10 ppc (3.11 kernel) and Mint 16 also.
[22:14] <kg7fu-2> r041.jpg to r104.jpg
[22:15] <sacarasc> That won't work then, %d stuff only works for 000 upwards without missing any.
[22:15] <kg7fu-2> so renumber then?
[22:15] <sacarasc> https://trac.ffmpeg.org/wiki/Create%20a%20video%20slideshow%20from%20images Look for the glob pattern part.
[22:16] <kg7fu-2> will try
[22:20] <kg7fu-2> awesome! tyvm I appreciate the help :)
[22:21] <kg7fu-2> now I can shut down the powermac it's like a 1000 watt bulb ;)
[22:21] <kg7fu-2> have a very nice day
[23:00] <llogan> sacarasc: there is the -start_number option for the image2 demuxer
[23:01] <sacarasc> Oooh, I didn't know that.
[23:01] Action: sacarasc tries to remember for next time.
[23:01] <llogan> how could you not remember the hundreds of individual options?
[23:02] <sacarasc> Sorry. :(
[23:02] <sacarasc> I will try better next time.
[23:02] <sacarasc> Please don't beat me again!
[23:28] <rcombs> when using -ss on an input file, can I have an output file use the original file's timestamps?
[23:42] <kingsob__> I have an audio stream, and I am trying to determine if it has a voice in it, is this something ffmpeg can do?
[23:51] <grepwood> Hi everyone
[23:52] <grepwood> I'm writing a game engine that will be using ffmpeg
[23:54] <grepwood> At this stage I'm just using 1 format from libavcodec
[23:55] <grepwood> Before I decide to actually use ffmpeg in its entire form, is it okay if I copy the bit that does this 1 format? As in, copy the source from ffmpeg's source to the engine's source
[00:00] --- Tue Mar  4 2014


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