[Ffmpeg-devel-irc] ffmpeg.log.20130101

burek burek021 at gmail.com
Wed Jan 2 02:05:01 CET 2013


[02:15] <pinkette> i have a video that video/audio is out of sync, how do i sync it permenantly
[02:22] <ubitux> -async option, aresample filter with async option
[05:41] <pinkette> i have a video that video/audio is out of sync: audio is ahead 500ms ;  what is the command to sync this video
[05:49] Last message repeated 1 time(s).
[07:47] <zap0> what have you got so far?
[10:17] <pinkette> i have a video that video/audio is out of sync: audio is ahead 500ms ;  what is the command to sync this video
[10:55] <ubitux> pinkette: 02:22:39 <@ubitux> -async option, aresample filter with async option
[10:55] <ubitux> pinkette: 07:47:49 < zap0> what have you got so far?
[10:55] <ubitux> please read instead of just asking the same question again and again&
[10:58] <pinkette> ffmpeg.exe -i input.mp4 -async 500  output.mp4  is this right?
[11:03] <ubitux> well if you want to shift the audio, maybe just -af asetpts=PTS+0.5/TB might be better
[11:04] <ubitux> also see https://ffmpeg.org/ffmpeg-filters.html#aresample-1
[11:11] <pinkette> ubitux -af ? i thought you said to use -async
[11:12] <ubitux> internally -async is doing a -af aresample=...
[11:16] <pinkette> why is it taking so long
[11:16] <pinkette> all i am doing is shifting
[11:20] <pinkette> why is it reencoding audio/video
[11:20] <pinkette> -af asetpts=PTS-0.5/TB   did sync the video though
[11:28] <ubitux> using filters means re-encoding
[11:28] <pinkette> i cannot accomplish this without reencoding video and audio?
[11:29] <ubitux> it would be nice, but i can't think of something like this right now
[11:29] <divVerent> you MAY accomplish it by remuxing using some tools, but I am not aware of any
[11:29] <divVerent> BTW, you only want to shift pts by that little?
[11:29] <divVerent> a half time base?
[11:29] <pinkette> okay can i accomplish this by reencoding audio only then and not touching the video
[11:30] <divVerent> oh sorry, 0.5 seconds
[11:30] <divVerent> if your output format is Matroska, mkvmerge can do this
[11:30] <ubitux> seems to be mp4
[11:30] <ubitux> maybe mp4box?
[11:30] <pinkette> i don't care if output is mp4
[11:30] <divVerent> it does it "somehow" without reencoding
[11:30] <pinkette> i don't care if output is mkv
[11:30] <divVerent> MP4Box may be able to do it too, see manpage
[11:30] <ubitux> pinkette: -c:v copy to avoid re-encoding the video
[11:31] <divVerent> in mkvmerge, see manpage for the keyword "delay"!
[11:31] <divVerent> sorry, exclamation mark unintended ;)
[11:31] <divVerent> is next to quote
[11:32] <pinkette> i have mkvmerge , where is delay settings
[11:32] <divVerent> option is -y
[11:32] <divVerent> -y trackid:delay
[11:32] <divVerent> track IDs may need guessing, but it'll either be 0 or 1
[11:33] <divVerent> guessing, or running mkvinfo on the mkvmerge'd mp4 :P
[11:33] <divVerent> the delay amount is in milliseconds BTW
[11:34] <ubitux> hey btw
[11:34] <ubitux> why don't you seek into the audio stream?
[11:34] <ubitux> by 500ms
[11:34] <divVerent> because that tends to require reencoding
[11:34] <divVerent> is my guess
[11:35] <divVerent> e.g. in opus, it'd be REALLY evil as opus actually has a sort of rolling keyframe concept
[11:35] <divVerent> basically, you can start decoding anywhere, but you need to decode a certain preroll amount of data to make the output correct
[11:35] <pinkette> wow mkvmerge does have delay option and it works without reencoding
[11:35] <ubitux> pinkette: can you try ffmpeg -i in.mp4 -ss:a 0.500 -c copy out.mp4?
[11:36] <divVerent> ubitux: actually
[11:36] <divVerent> I now see why it won't work :P
[11:36] <divVerent> or rather, shouldn't work
[11:36] <divVerent> it won't make the pts match up
[11:36] <divVerent> but encode so it has 0.5 sec of video before the audio stream starts
[11:36] <ubitux> i'd suggest to try anyway
[11:36] <divVerent> or not?
[11:36] <divVerent> sure, worth trying it is
[11:36] <divVerent> IF it works, it's better than mkvmerge's shifting
[11:37] <ubitux> not sure if -ss:a will seek only the audio thought =)
[11:37] <divVerent> because the video will then not start with 0.5 sec of audio before video comes ;)
[11:38] <pinkette> ffmpeg -i in.mp4 -ss:a 0.500 -c copy out.mp4  did not work
[11:38] <ubitux> ok :(
[11:38] <pinkette> but mkvmerge worked
[11:38] <divVerent> just out of interest
[11:38] <divVerent> is the mkv file bigger or smaller than the mp4?
[11:39] <pinkette> 4M smaller
[11:39] <divVerent> I noticed mkv'ing files save quite a lot of space (near one percent) on AVIs
[11:39] <ubitux> :)
[11:39] <divVerent> no idea how they achieve that
[11:39] <pinkette> mkv has one 2 negative things
[11:39] <pinkette> mkv has 2 negative things though
[11:39] <divVerent> as "binary XML" doesn't sound very promising if you want to conserve space
[11:40] <pinkette> aac with mkv  ,you cannot see bitrate-audio   where aac with mp4 can
[11:40] <divVerent> pinkette: one is EBML, and the other is the (by default) 1ms granularity?
[11:40] <divVerent> that may be a mere issue of the tools, though
[11:40] <divVerent> and the other?
[11:41] <pinkette> in windows-explorer  i cannot see detail video  on mkv  but i can with mp4/avi/wmv
[11:42] <pinkette> such as fps/resolution
[11:43] <pinkette> how does mkvmerge fix  audio shifting  without reencoding
[11:43] <ubitux> well since the ts are stored at container level&
[11:44] <pinkette> so if i do   ffmpeg -i  mkvmergedfixedfile.mkv  output.mp4,   would the output.mp4 go  out of sync ?
[11:44] <ubitux> i don't think so
[11:44] <ubitux> even with -c copy
[11:45] <pinkette> i should try it; just in case
[11:46] <ubitux> can you share the sample btw?
[11:46] <ubitux> also, how come you ended up with shifted audiO?
[11:47] <ubitux> audio*
[11:47] <pinkette> i have no clue
[11:47] <pinkette> okay output.mp4 did NOT go out of sync
[11:47] <pinkette> wow, mkvmerge is powerful
[11:48] <pinkette> i have a video where tint/hue is way off,  can ffmpeg fix this
[11:49] <ubitux> -vf hue
[11:50] <pinkette> that requires reencoding the video. right?
[11:50] <ubitux> of course
[11:51] <pinkette> i wonder what causes to "audio out of sync" and  tint/hue being way off
[11:53] <ubitux> what's your source?
[11:53] <pinkette> camera
[12:10] <retard> true fact: almost all video comes from camera
[12:10] <ubitux> not animes
[12:11] <retard> ubitux: depends
[12:11] <ubitux> not good animes
[12:11] <retard> s/good/new
[12:12] <pinkette> retard exactly
[12:39] <pinkette> ffmpeg -i input.avi -vcodec copy -acodec copy output.mkv   does not work
[12:40] <pinkette> [matroska @ 03439600] Can't write packet with unknown timestamp
[12:40] <pinkette> av_interleaved_write_frame(): Invalid argument
[12:40] <Yulth> Happy new year for everyone!
[12:41] <Yulth> Could anybody help me please with the error returned by this command?  :) http://pastebin.com/UwjXT9JV
[12:57] <ubitux> pinkette: try -fflags +genpts
[12:57] <pinkette> what is that
[13:03] <ubitux> generate presentation timestamps
[13:03] <ubitux> because avi hasn't any afaik
[13:04] <ubitux> (or missing some for b-frame stuff or something)
[13:04] <ubitux> there is an opened trac issue to make it default when necessary
[13:05] <ubitux> Yulth: [libaacplus @ 0x805d41620] libaacplus doesn't support this output format!
[13:05] <ubitux> libaacplus: bad aac setting: br:40000, AACch:65536, AACsr:22050
[13:05] <ubitux> -ab 40k  you sure that is correct?
[13:06] <ubitux> AACch:65536  this is funny :)
[13:16] <Yulth> ubitux: of course, it works using libfdk_aac -profile:a aac_he. So, is not the same for libaacplus?
[13:17] <ubitux> maybe these settings are just not supported
[13:17] <Yulth> mmm, perhaps libaacplus doesn't suport HE-AAC encoding... T_T
[13:18] <Yulth> so, is libfdk_aac the only way to encode HE-AAC?
[13:18] <Mavrik> um.
[13:18] <Mavrik> "AAC+" == "HE-AAC"
[13:18] <Mavrik> what makes you think a library named "AAC+" wouldn't be able to encode that format? :P
[13:19] <Mavrik> the glue code is kinda buggy
[13:19] <Mavrik> try removing channel spec or the profile spec
[13:20] <Yulth> let my try it
[13:20] <Mavrik> since the lib obviously thinks you're trying to set 65535 channels.
[13:21] <Mavrik> FDK-AAC is more stable and provides output for wider range of audio though
[13:22] <Yulth> it doesn't work neither removing -ac nor -profile:a
[14:12] <gxk> i am beginning project which streams live h264 video by mpeg2ts/udp. the streaming with mpeg2ts is what i am missing. i don't have audio, but there is metadata. is ffmpeg the right project to start?
[14:13] <Mavrik> yes, ffmpeg can stream MPEG2-TS/UDP with H.264/AAC in it
[14:17] <gxk> is there demo/example for it? may be not exact but close enough
[14:18] <Mavrik> hmm, not really
[14:18] <Mavrik> ffmpeg -i <file> <h264 encoding parameters> -bsfs h264_mp4toannexb -f mpegts udp://127.0.0.1:5000
[14:18] <Mavrik> that usually does the trick
[14:30] <gxk> is there example how to add ffmpeg for live h264 and from file?
[14:33] <gxk> Mavrik: the option '-bsfs' or '-bsf' or '-vbsf'?
[14:33] <Mavrik> er, yea, sorry
[14:34] <Mavrik> any of -bsf, -vbsf, -bsf:v
[14:34] <Mavrik> depending on your ffmpeg version
[14:37] <gxk> Which encoding parameters to use, if i want to send h264 from file?
[14:42] <Mavrik> um
[14:42] <Mavrik> whichever you want depending on quality and bitrate you have?
[14:44] <BtbN> works great for me without any special parameters except my desired bitrate.
[14:44] <BtbN> and resolution
[14:52] <gxk> is there option to start from beginning of a file when reach end of a file?
[14:54] <sacarasc> There might be a -loop
[14:55] <gxk> sacarasc: nope :(
[15:41] <gxk> are there well known h264 files to test with?
[16:17] <espr3ss0> hi
[16:20] <espr3ss0> anyone here ?
[16:28] <espr3ss0> what's the "--enable-nonfree" option ?, does ffmpeg cost ? o_O
[16:29] <sacarasc> Some licences are not 100% free.
[16:29] <sacarasc> To use the libraries with these licenses, you have to use that option.
[16:29] <espr3ss0> I'm assuming that I'm installing libraries to be able to work with files e.g. audio track 'mp3' i need "Lame" & so on & so forth
[16:33] <espr3ss0> is there a location for DivX Library ?
[16:39] <sacarasc> Depends where you installed it.
[16:39] <espr3ss0> fair enough
[16:41] <espr3ss0> I have a "MacBook 13" White" & have installed "OS X SnowLeopard" ... do i need to set "--arch=x86_64" ?
[16:42] <espr3ss0> I'll set it anyway
[16:42] <klaxa> hmm i guess set --arch=native
[16:42] <klaxa> if that's possible
[16:42] <sacarasc> You shouldn't need to do that at all.
[16:42] <klaxa> unless you want to cross-compile
[16:43] <espr3ss0> noo
[16:43] <espr3ss0> is this missing anything ? ... "./configure --enable-gpl --enable-nonfree --enable-libmp3lame --enable-libx264 --enable-libmp4v2 --disbale-mmx"
[16:43] <espr3ss0> wanting to only setup for common .avi's & mp4's
[16:44] <espr3ss0> or more specifically from ".avi" to ".mp4"
[16:44] <creep> how do guys run their ddr3 1866 with i5 ?
[16:59] <espr3ss0> "unknown option '--enable-libmp4v2'" ? o_O
[16:59] <sacarasc> ffmpeg doesn't need it.
[16:59] <sacarasc> It has its own MP4 writing library.
[17:00] <espr3ss0> oh
[17:00] <espr3ss0> i only assumed because when I tried to "no transcode" an avi to mp4 the mp4 video was very jumpy :-/
[17:03] <espr3ss0> brb, afk
[17:22] <gxk> q
[17:25] <espr3ss0> hmm, once again ... where can i download "libxvid" from ?
[17:25] <espr3ss0> i will paste some info but not yet
[17:27] <gxk> while streaming from h264 file, got in command line status with fps=298. the comand line: ffmpeg -i ./test.h264 -s 1280x720 -b:v 2M -r 30 -bsf h264_mp4toannexb -f mpegts udp://127.0.0.1:5004
[17:55] <Mavrik> gxk, add "-re" at the start of parameters
[17:55] <Mavrik> gxk, this will tell ffmpeg to stream with playback speed
[17:57] <gxk> Mavrik: thanks
[18:31] <gxk> Mavrik: vcl shows statistics, but still no video. it also shows frame rate 60, while i am sending 30. is this a problem?
[18:34] <Mavrik> well, probably.
[18:56] <gxk> Mavrik: it was vlc problem on my Ubuntu. not installed properly.
[18:59] <espr3ss0> if i'm wanting to extract "h.264" video track, do I need the x264 library "libx264" ?
[19:00] <JEEB> no
[19:00] <espr3ss0> also seen a method of extracting to "video.h264", but no idea how to use that after for an input
[19:00] <JEEB> x264 is just for encoding
[19:01] <JEEB> ffmpeg -i input -an -sn -c copy -f h264 out.h264
[19:01] <JEEB> if it's mp4, you will need the mp4-to-annexb filter
[19:01] <JEEB> because mp4 contains the H.264 stream in a diff. way
[19:01] <espr3ss0> oh
[19:02] <JEEB> (and raw H.264 is in a format called Annex B because it's defined there in the specification)
[19:02] <JEEB> http://ffmpeg.org/ffmpeg-bitstream-filters.html#h264_005fmp4toannexb
[19:02] <JEEB> this one
[19:02] <JEEB> you don't need it for other formats
[19:02] <JEEB> just mp4
[19:03] <JEEB> (I don't know exactly why ffmpeg doesn't do this conversion automatically when needed)
[19:04] <espr3ss0> i'm confused
[19:04] <JEEB> ask away
[19:04] <espr3ss0> if i'm wanting to simply copy from the ".avi" container to an ".mp4", how can i achieve this ?
[19:05] <JEEB> oh
[19:05] <JEEB> I thought you wanted to really /extract/ the H.264 track :D
[19:05] <JEEB> which means demuxing from a container to a raw Annex B stream
[19:05] <espr3ss0> well, i do want to be able to demux
[19:05] <JEEB> basically you want to remux the video, what about the audio?
[19:06] <espr3ss0> mainly only common rips
[19:06] <JEEB> ...
[19:06] <espr3ss0> but also some mp4's arn't done in the right way, which causes me some problms
[19:06] <JEEB> I asked what you wanted to do to the audio
[19:06] <espr3ss0> my main aim is no transcoding
[19:06] <JEEB> ok
[19:07] <JEEB> ffmpeg -i input -c:v copy -c:a copy out.mp4 and it should happily copy stuff over in most cases, except when you have a video or audio track that isn't such that can be put into "MP4"
[19:08] <espr3ss0> oh, including both Video & Audio
[19:08] <JEEB> that of course doesn't select all tracks from the input clip, only the "best" video and "best" audio track
[19:08] <espr3ss0> i tried ... ffmpeg -i file -vcodec copy -acodec copy outfile.mp4
[19:09] <JEEB> that should work too I guess
[19:09] <JEEB> (that's the older syntax)
[19:09] <espr3ss0> the video comes out slow n jumpy
[19:09] <espr3ss0> :-/
[19:09] <JEEB> what are you playing it in?
[19:09] <JEEB> also... inb4 PTS values need to be generated if it's H.264 in avi
[19:10] Action: JEEB checks the logs, IIRC there was something about that today
[19:10] <espr3ss0> QuickTime, VLC works fine
[19:11] <JEEB> QuickTime is known to be problematic, but you could try adding -fflags +genpts in case of AVI + H.264
[19:11] <espr3ss0> will be playing the mp4's on iPad (gen 3)
[19:11] <JEEB> the iPad might actually play it better than QuickTime
[19:11] <JEEB> funny enough :P
[19:11] <espr3ss0> strangly does :-)
[19:11] <JEEB> QuickTime is just like that, they've always had more or less problems with H.264 and friends
[19:12] <JEEB> although lately IIRC they did somewhat better after they switched mostly to hardware decoding
[19:12] <JEEB> which of course is limited in some ways
[19:12] <JEEB> but should still be better in other ways
[19:12] <JEEB> (than what QT used to be)
[19:12] <espr3ss0> heh
[19:13] <JEEB> also Apple is known to ignore a lot of the bug reports they get about these issues
[19:13] <JEEB> so meh
[19:13] <espr3ss0> :-/
[19:13] <espr3ss0> erm, quick Q ...
[19:13] <espr3ss0> is this type of error normal ? "libavformat/metadata_compat.c:143: warning: language is deprecated (declared at libavformat/avformat.h:602)"
[19:13] <espr3ss0> when making ffmpeg
[19:13] <JEEB> it's a warning, not an error
[19:14] <espr3ss0> oh, does it matter ?
[19:14] <JEEB> and yes, it's OK -- it just tells you that that file uses something that is declared deprecated in the public API
[19:14] <JEEB> and since it's within ffmpeg itself
[19:14] <JEEB> it will get updated/removed when the deprecated API is removed
[19:15] <espr3ss0> depricated mean ignored /rejected ?
[19:15] <JEEB> no, it means old
[19:15] <espr3ss0> ooooh i c
[19:15] <JEEB> that there (generally) is a new way to do it
[19:15] <JEEB> as the file name says _compat (compatibility)
[19:15] <JEEB> I would guess it contains some old stuff
[19:15] <JEEB> basically with one version you deprecate
[19:15] <espr3ss0> gonna have to be bbs, thanks 4 ur help :-)
[19:15] <JEEB> and then in the next version you remove
[19:15] <JEEB> np
[19:16] <espr3ss0> cool
[19:33] <Sashmo> doese anyone know if there is a way to add the soruce name to the file name output?? http://pastebin.com/D7GXGYSx
[19:35] <Sashmo> I'm assuming theres a bash expression that can do it..... no?
[19:51] <grepper> Sashmo: its unclear what you want - could you give an example of an output name you would want ?
[19:51] <Sashmo> basicly, I want my source file name to be the same as the screenshot file name, but not have to make a bash script to make it work
[19:58] <grepper> no idea what you are talking about without an actual example, as I asked
[19:59] <sacarasc> They want to have the output name have the same basename as the input name.
[19:59] <sacarasc> Without using a whole script, it seems.
[20:00] <Sashmo> here http://pastebin.com/UhqU918c
[20:03] <grepper> Sashmo:   ${source##*/} would be the basename of the file without the path
[20:04] <grepper> "${source##*/}"  (should be quoted in case of spaces in name)
[20:05] <Sashmo> grepper: so like this? http://pastebin.com/84h2b9dA
[20:10] <grepper> source=/home/sashmo/foo.avi ;  ffmpeg -i "$source" ... -y "${source##*/}_%d.jpg"
[20:10] <grepper> or somesuch
[20:10] Action: grepper bbl
[20:10] <Sashmo> grepper: thanks
[20:10] <Sashmo> will try
[20:14] <grepper> if you don't want the extension in the filenames, (ie. just foo_01.jpg instead of foo.avi_01.jpg) you can do: source=${source##*/}; source=${source%.*}  , before feeding the variable to the ffmpeg command line
[20:15] <Sashmo> I was just trying that now.... the problem is that the source is a URL.....
[20:16] <espr3ss0> JEEB: u still there ?
[20:40] <espr3ss0> put an mp4 track (x264) and an aac together with "copy" but audio has 0 channels & should have 2
[20:41] <espr3ss0> h.264 ! 8-/
[20:44] <espr3ss0> still need xvid & divx to work
[20:45] <espr3ss0> ... ping ! ... pong ! ... o_O
[21:46] <espr3ss0> can anyone say if xvid = divx ?
[21:48] <espr3ss0> hmm guess not
[21:48] <espr3ss0> all i can see is enabling "libxvid" & no divx ! :-(
[21:49] <creep> a girl starts to turn into a dragon after 17-th birthday ?
[21:53] <espr3ss0> ffmpeg, after "./configure etc." is it necessary to "make" & install every time ?
[22:23] <octocpp> can ffmpeg use multiple threads to encode with libmp3lame ? I use -threads 0  or threads 8 and it does the same thing, I only see one process in htop?
[22:29] <BtbN> lame is only single threaded.
[22:33] <octocpp> ok, thanks, Im using winff ans a gui, would be cool if it ran a script for every song i was trying to convert, or maybe ran 4 seperate scripts and split the songs up 4 ways. That would nice.
[22:35] <sacarasc> octocpp: Try using dbpoweramp for Windows... It is multithreaded.
[22:36] <octocpp> arg, im in linux right now though.
[22:36] <octocpp> soundKonverter worked really good, but it was not able to get the tags right for some reason.
[22:37] <octocpp> Basically lost them all
[22:40] <espr3ss0> Q: can ffmpeg correct "B Frames" ? ... "[mpeg4 @ 0x101024400] Invalid and inefficient vfw-avi packed B frames detected"
[22:49] <espr3ss0> QuickTime "invalid sample description", fix with ffmpeg ?
[22:49] <espr3ss0> plays fine in VLC
[22:58] <espr3ss0> ".avi mpeg-4 xvid" to "m4v(mpeg-4) .mp4", same thing ? vcodec copy
[22:58] <espr3ss0> this is too complicated ! ;-p
[23:14] <misterno> what is absolute best quality encoding?
[23:15] <sacarasc> Lossless.
[23:16] <misterno> what is absolute best quality encoding for around 800 MB size movie?
[23:17] <sacarasc> Two pass x264?
[23:17] <misterno> there were some movies in MKV container around only 400MB that had amazing quality, how is that possible?
[23:18] <sacarasc> Some codecs are better at compressing than others.
[23:18] <misterno> do you have any idea which codec might be used in those 400 MB MKVs?
[23:18] <sacarasc> Probably H264 encoded by x264.
[23:18] <misterno> i can find that out using media info right?
[23:18] <sacarasc> But if you have the files, you could see.
[23:20] <misterno> i don't want to talk about piracy but i must just touch it because i want to understand quality.... you are saying probably one of best is x264 twopass, how come groups release xvids is it considered good quality or not?
[23:21] <sacarasc> No sane person uses XviD or DivX any more.
[23:21] <Adys> I have an mkv movie with two audio tracks (one french, one english); I want to delete the french one. any idea how?
[23:22] <misterno> ok, are there tools you can recommend to me to use to get this x264 two pass encoding, handbrake?
[23:22] <leoj3n> misterno: x264 is in all the tools, so it 2 pass
[23:22] <sacarasc> Adys: ffmpeg -i blah.mkv -map 0:0 -map x:1 -c copy output.mkv. Replace x with the track number of the English audio.
[23:22] <Adys> i see, thanks :)
[23:22] <misterno> ok, and for container you guys recommend mkv?
[23:23] <misterno> even though it is not supported by standalone dvd players
[23:23] <misterno> mkv is superior because it can contain subtitles and multiple audio tracks right?
[23:25] <JEEB> yes, it's superior for such usage because of its capability of keeping various types of streams within it. Unlike the "MP4" family of containers which is unfortunately quite limited by the fact that not much in the end has been specified for it
[23:26] <misterno> how do you guys go about setting up resolution for dvd movie, and then resolution for lets say bluray
[23:26] <misterno> is it better to have lower res and higher quality or higher res
[23:27] <JEEB> uhh, I just use x264's crf rate control to more or less control the "general level of quality"
[23:27] <JEEB> I don't encode for set file sizes :s
[23:27] <misterno> but do you manually set resolution yourself?
[23:28] <misterno> i haven't encoded yet so im a bit blank on it, although i did try in the past then i realized so many options
[23:28] <JEEB> for DVDs I usually just deal with interlacing if there's any, crop and set aspect ratio, for blu-rays I generally try to see how much actual detail there is in the source
[23:28] <misterno> do you do differently for action movie vs drama?
[23:29] <JEEB> no
[23:29] <misterno> doest it matter if picture is moving fast vs slow
[23:29] <JEEB> no
[23:29] <misterno> hmm i was quite sure that mattered in the past for quality settings
[23:30] <misterno> perhaps with xvid
[23:30] <JEEB> yes, x264's crf will take into notion how "fast" the stuff is going in the scene and somewhat higher quants get used for fast scenes... but uhm... that has NOTHING to do with resolution
[23:31] <misterno> yes but if you look at file size then lower resolution alows more space for quality
[23:31] <misterno> *fixed file size
[23:31] <JEEB> yes, if you are running out of bits (aka have set your file size lower than it'd be appropriate for the content
[23:31] <klaxa> meh, either you speak bitrate or quality
[23:32] <misterno> oh you reminded me, what do you consider ok minimum bitrate?
[23:32] <JEEB> there is no such thing
[23:32] <misterno> you dont have personal preferences?
[23:32] <misterno> i always have personal preferences on anything
[23:32] <JEEB> I stopped throwing numbers at a wall with x264
[23:32] <JEEB> about four years ago
[23:32] <misterno> ok
[23:33] <JEEB> the minimum bitrate for a given source is the bit rate you get with the highest crf value that still looks good to you
[23:33] <JEEB> that is personal, because your eyes are your eyes
[23:33] <JEEB> if you do not have a strict limit you have to abide to, you use crf. Simple as that, and doesn't need a second pass
[23:33] <misterno> yes i understand thats why i asked for your own personal preference :)
[23:33] <misterno> i know you dont want to make claims this is better than that or so
[23:34] <misterno> can i just ask, is there much difference in quality between lets say full blown adobe premiere vs some open source tol?
[23:34] <misterno> *tool
[23:35] <JEEB> well, adobe stuff uses mainconcept
[23:35] <JEEB> and mainconcept came second or so after x264 in MSU's tests
[23:35] <misterno> oh man theres so much info on this for someone new to this it is mind bogling getting grasp of it
[23:36] <JEEB> it's not really that hard nowadays
[23:36] <misterno> so i have to google these MSU tests, this is first time i hear on this
[23:37] <JEEB> grab a thing you want to encode, encode around 5000 frames of it with various crf values after doing your thing (handled interlacing in one way or another, cropped, possibly resized if the source is of lower detail than the source media [f.ex. Japanese animation often is 540p-720p area, not the 1080p that's on the Blu-ray discs f.ex.]), starting from crf 23
[23:37] <JEEB> if it looks good, go up
[23:37] <JEEB> if it looks bad, go down
[23:38] <JEEB> then when you've found the highest crf value that still looks good for you
[23:38] <misterno> jeeb what is the story with interlacing, is that because of TVs? and then we have to deinterlace for pcs?
[23:38] <JEEB> oooh boy
[23:38] <misterno> ok nvm ill just google that
[23:38] <JEEB> nah
[23:40] <JEEB> anyways, let's just keep to progressive content for now
[23:41] <leoj3n> misterno: http://www.youtube.com/watch?v=j29b7B6CSNM
[23:42] <JEEB> 1) you crop the source [overcropping is better than undercropping] 2) you resize the video as you see fit [features that might be reasons to downscale: bad quality of source, lack of detail and so forth and so forth]
[23:43] <misterno> how come movies get nuked when they crop? again im not promoting piracy i just want to understand quality
[23:43] <JEEB> aka you define the settings for these two, these have nothing to do with the actual encoding, this is basically handling the source before feeding it to the encoder
[23:43] <foonix_> sometimes i try to find good resolution (on upscaled sources) by doing eye test: resize original->lower->original a compare how much detail is lost
[23:44] <foonix_> misterno: on things like 960x544 crf 16 is awesome, but final size might not be ok for everyone.. so just test whats ideal for you
[23:45] <JEEB> foonix_, STOP TELLING PEOPLE TO JUST USE A RANDOM NUMBER
[23:45] <JEEB> THAT IS BAD
[23:45] <JEEB> PLEASE
[23:45] <JEEB> FOR THE LOVE OF DERP STOP THAT
[23:45] <misterno> whoa
[23:45] <misterno> no need to get angry jeeb :)
[23:45] <foonix_> i told him some idea, ok it included numbers
[23:45] <misterno> first im complete newb to this, i dont understand half what you guys are saying and will have to google it
[23:45] <JEEB> you gave him a number that might look good from the get go
[23:46] <JEEB> that means he might NEVER TRY HIGHER NUMBERS
[23:46] <JEEB> 23 is better off because it generally should lead to better compression and might not look good from the beginning
[23:46] <misterno> so you prefer to stick to 570p 720p?
[23:46] <foonix_> if its ok for him, i dont have problem with that
[23:46] <JEEB> oh for fuck's sake
[23:46] <misterno> or you talking cfr?
[23:46] <JEEB> we're talking about crf values
[23:47] <misterno> alright
[23:47] <JEEB> misterno, I have no idea the procedures the "scene" has but proper cropping is at max a few pixels over if the area of the black borders changes around
[23:47] <JEEB> and that should be just fine unless you are encoding for some plastic boxes, although I would guess that'd work in most cases as well
[23:47] <JEEB> foonix_, do you not see at all why giving a newbie a too low crf value to start with might be problematic? At all?
[23:48] <JEEB> It's good if the person ends up finding that for a given source X crf 19 is the highest value that still looks good
[23:48] <JEEB> I mean, you can test various crf values with like 2500-5000 frames' worth of content
[23:48] <foonix_> well then dont give him 5k frames sample too
[23:48] <JEEB> also x264 has a default, 23
[23:49] <foonix_> kinda absurd
[23:49] <JEEB> well generally I tell people to cut a few hundred frames' samples from various parts of the source, but I have no idea how you can cut easily with ffmpeg like that
[23:49] <misterno> yes but wait, if i have fixed file size then CRF will adjust to that wont it?
[23:49] <JEEB> so I just tell them to ss to some part of the movie that is generally like the source is
[23:49] <JEEB> no
[23:49] <JEEB> CRF is "constant quality"
[23:49] <JEEB> has no file size limitations set to it at all
[23:49] <JEEB> other than possibly vbv
[23:50] <JEEB> but that's a separate discussion
[23:50] <misterno> so if i use fixed file size then no crf
[23:50] <JEEB> yes, but you seemingly have no idea to what bit rate you want to limit yourself
[23:50] <JEEB> thus I see no reason to keep your to bitrate-based encoding
[23:50] <JEEB> *you to
[23:50] <misterno> i can get that idea by looking at bitrates of movies i see from others
[23:50] <JEEB> ...
[23:51] <JEEB> > copycat'ing scene "rules"
[23:51] <JEEB> let me facepalm here
[23:51] <JEEB> hard
[23:51] <JEEB> unless you have to participate in the "scene"
[23:51] <misterno> dont face palm just because someone is interested in learning more
[23:51] <JEEB> you have no reason to limit yourself to the shit they use
[23:52] <misterno> and i probably wont but i wanna try everything
[23:52] <JEEB> because the most I see of those "scene" folk is being utter retards who have to be limited to not the most crappiest settings because everyone wants to be the first and thus people would encode with the worst settings possible otherwise
[23:52] <misterno> i wanna try both fixed file size and not
[23:53] <misterno> ok can i ask a bit of different question, i would like to encode file best i can for upload to youtube, dont want to waste bandwidth by uploading uncompressed file
[23:53] <misterno> do i still go for x264 two pass?
[23:53] <JEEB> foonix_, also I see your comment about "Giving 5000 frame sample" absurd being weird in itself, you should be able to grasp the general quality that you will be getting from a certain crf value with that. 500 frame parts from various parts of the source would be better, but as I said I have no fucking idea how to do that with ffmpeg
[23:54] <misterno> i have noticed some people make excellent youtube quality videos and some dont
[23:54] <JEEB> misterno, youtube is going to rape your thing anyways so just use the lowest crf that doesn't seem to be ending too big, lossless being the biggest thing. x264's lossless should still be way smaller than uncompressed video.
[23:54] <misterno> alright
[23:54] <JEEB> also audio could be something lossless if you really want to give youtube the best thing to rape
[23:57] <misterno> what do you think of this comparison http://www.tools4movies.com/2012/03/crf/
[23:57] <misterno> and that tool
[23:58] <JEEB> what the flying fuck
[23:58] <JEEB> why the fuck is he saying with "CRF" off
[23:59] <misterno> don't ask me :)
[23:59] <misterno> you're the expert here
[00:00] --- Wed Jan  2 2013


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