[Ffmpeg-devel-irc] ffmpeg.log.20160316

[burek]

[00:00:20 CET] <jookiyaya> yes i do remember reading about TN panels are only 6bit
[00:01:35 CET] <iive> that makes them 18bit
[00:02:15 CET] <J_Darnley> Yep, they could be pretty shit
[00:02:29 CET] <J_Darnley> hence, crt=master race
[00:06:12 CET] <iive> they actually use dithering
[00:07:33 CET] <TD-Linux> even 8bit panels do dithering due to nonlinear correction
[00:09:18 CET] <jookiyaya> why do gamers always talk about "faster fps"  if  film  still to this day still use  23.97 fps
[00:10:56 CET] <pzich> jookiyaya: because you don't need a crazy-fast response time for a film
[00:11:04 CET] <jkqxz> Because smooth playback for viewing and minimise-latency playback to react to are not the same thing at all.
[00:11:48 CET] <drv> also, have you ever seen a fast camera pan in film? it looks awful
[00:12:39 CET] <furq> you can very clearly tell the difference between 60fps and 120fps
[00:12:44 CET] <furq> especially if the only game you play is quakeworld
[00:13:46 CET] <jookiyaya> why is bluray still using 23.97 then
[00:14:34 CET] <furq> because films are shot at 23.97fps
[00:15:25 CET] <jookiyaya> people don't seem to care improve the fps
[00:15:39 CET] <furq> there have been films shot at 48 or 60fps
[00:15:48 CET] <furq> people didn't like it because it made everything look like a mexican soap opera
[00:15:53 CET] <jookiyaya> they seem to care about resolution though, since we are even at 4k now
[00:15:57 CET] <furq> like most fancy TVs with motion compensation do
[00:16:12 CET] <jookiyaya> mexican soap opera?  i don't get it
[00:16:45 CET] <furq> mexican soap operas are shot on video (30fps) because they are cheaply made
[00:17:06 CET] <furq> it applies equally to anything which was shot on video and not film
[00:17:28 CET] <furq> are there any more jokes you'd like me to explain
[00:18:37 CET] <jookiyaya> but i am sure a lot of things are shot at 30fps  not just soap opera
[00:19:32 CET] <jookiyaya> somebody just typed to me this too:   [16:11] <PrincessKnoeki> 60fps looks too much like TV soaps :D
[00:21:03 CET] <jookiyaya> A reader recently commented that he would never buy a 4K LED/LCD television because of the Soap Opera Effect
[00:21:43 CET] <jookiyaya> i just don't understand  why call it "soap opera effect"  . i am sure there many things that use 30 fps
[01:12:49 CET] <kepstin> 30fps progressive content is actually fairly rare
[01:13:21 CET] <kepstin> the thing that most people notice as the "soap opera effect" is up in the 50-60fps range (traditionally, this is interlaced content, so 50-60 fields per second)
[05:21:41 CET] <Dominian> morning all... here's a paste of a command I'm trying.. raw stream to .ts... tired and out of ideas: http://pastebin.com/JVy8h1Rn
[05:21:46 CET] <Dominian> any help would be appreciated
[05:21:50 CET] <Dominian> probably.. something stupid
[05:28:24 CET] <J_Darnley> --disable-muxers and you wonder why ffmpeg doesn't know what .ts is?
[05:29:33 CET] <J_Darnley> hint: [NULL @ 0x2125720] Unable to find a suitable output format for 'testing.ts'
[05:29:56 CET] <J_Darnley> and with that, good night
[05:31:02 CET] <Dominian> Nope.. great answer though
[05:34:02 CET] <furq> oh hey it's that useless suse package again
[05:34:49 CET] <Dominian> So, quick fix or no?
[05:35:02 CET] <furq> http://johnvansickle.com/ffmpeg/
[05:35:29 CET] <furq> iirc the last time this came up someone found a different suse package which didn't have everything even vaguely associated with mpeg-la removed
[05:35:41 CET] <furq> but i'm too lazy to search the logs for it, and those builds will work
[05:36:05 CET] <Dominian> no worires
[05:36:07 CET] <Dominian> probably something in packman
[05:36:09 CET] <Dominian> thanks
[05:52:16 CET] <Dominian> furq: thank you for the link.. much better than the other guys suggestion
[09:32:12 CET] <osense> hello
[09:32:42 CET] <osense> I'm trying to cancat video with the demuxer on ffmpeg 3.0 and I'm getting "Protocol not on whitelist 'none'!"
[09:32:45 CET] <osense> any ideas?
[09:32:51 CET] <osense> concat videos, even
[09:34:33 CET] <osense> http://pastie.org/10762015
[09:36:25 CET] <relaxed> ffmpeg -h demuxer=concat
[09:36:59 CET] <relaxed> -safe 1
[09:37:11 CET] <osense> prepending -safe 0 before -i makes no difference :(
[09:37:15 CET] <relaxed> er, maybe it's -safe 0
[09:37:38 CET] <osense> hmm
[09:37:49 CET] <osense> okay, when I put in -safe 1 I get "Unsafe file name '/srv/http/20160316.mp4'"
[09:38:02 CET] <osense> so it seems like -safe 0 was already being used?
[09:51:51 CET] <relaxed> osense: try -protocol_whitelist file
[09:54:23 CET] <osense> relaxed: this now gives "Protocol not on whitelist 'file'!" (this is different to the original error message)
[09:56:09 CET] <osense> I wonder if this is all because I'm trying to pipe in the filenames instead of using a text file as input
[09:57:33 CET] <osense> yeah, works fine with file asd input
[11:53:02 CET] <Cyber_Akuma> Just have a quick question, does it matter where I use the "-threads" command? Can I use as my first argument before -i for the input file?
[14:28:47 CET] <SixEcho> trying to convert gopro mp4 to webm:vp9/opus ffmpeg -i file.mp4 -vcodec libvpx-vp9 -acodec opus -crf 10 -b:v 0 -b:a 128k file.webm    but it's processing at only 3fps& way too slow.  suggestions?
[14:30:21 CET] <J_Darnley> Get a faster computer.
[14:30:23 CET] <SixEcho> MBP mid-2012 4xi7-2.7ghz& make that 0.3fps
[14:30:28 CET] <J_Darnley> Make sure you are using the latest version
[14:30:58 CET] <SixEcho> J_Darnley: i'm on 3.0 with the latest libvpx as well
[14:32:05 CET] <J_Darnley> Meh.  Its libvpx.  I don't really care.
[14:45:32 CET] <luc4> Hello! I would like to stream data (raw audio and video frames) through the network. I was thinking about RTP. Is there an example on how to stream like this using the C libraries?
[15:22:38 CET] <Raz-X> hi everyone
[15:22:59 CET] <Raz-X> I have some questions about streaming with ffmpeg
[15:23:45 CET] <Raz-X> i have to get a video (unknown format), transcode it in mjpeg, and stream it over http
[15:24:15 CET] <Raz-X> i'm able to do this with the ffmpeg+ffserver combo, but can i achieve this with just ffmpeg?
[15:24:36 CET] <vexii> im trying to create a video file from a series of jpegs, but i get a "Error wile opening encoder", the command im trying to is "ffmpeg -start_number 2216 -i IMG_%03d.jpg -c:v libx264 out.mp4"
[15:24:45 CET] <Raz-X> cuz the problem with ffserver is that it has to be restarted entirely to add a new stream
[15:25:01 CET] <vexii> (the first jpg is named IMG_2216.jpg)
[15:25:14 CET] <Raz-X> any advices?
[15:27:33 CET] <eghdk> If I give ffmpeg a mpeg4 file, is it easy enough to crop the video size down?
[15:27:59 CET] <eghdk> Example: I have an mpeg4 video, but I want it to be a square video.
[15:43:50 CET] <J_Darnley> eghdk: see the crop filter
[15:49:47 CET] <vexii> J_Darnley: sorry, here is the command http://pastebin.com/zxAUMaK7
[15:50:17 CET] <J_Darnley> OMFG!  We want the full output as printed to your terminal!
[15:50:56 CET] Action: J_Darnley notes you already gave us the command
[15:51:17 CET] <vexii> chill dude... http://pastebin.com/iTZCEc2i
[15:51:34 CET] <J_Darnley> Read the error!
[15:51:36 CET] <J_Darnley> [libx264 @ 0x558e2599dba0] width not divisible by 2 (4701x3134)
[15:51:47 CET] <J_Darnley> It should be highlighted in red!
[15:52:01 CET] <vexii> and how do i handle that ?
[15:52:09 CET] <J_Darnley> scale, pad, or crop
[15:52:48 CET] <vexii> why do the file need to have a width divisible by 2? no resizing is going on
[15:53:09 CET] <J_Darnley> How can you have half a chroma sample?
[15:53:18 CET] <vexii> what?
[15:53:39 CET] <J_Darnley> Read about chroma subsampling if you really want to know.
[15:56:22 CET] <vexii> hmm kind of expected that to be encoding dependent, but guss not
[15:56:37 CET] <vexii> so the only way is to resize alle the files`
[15:56:39 CET] <vexii> ?
[15:56:57 CET] <J_Darnley> Yes, or just let ffmpeg do it while encoding
[15:57:09 CET] <J_Darnley> Well, tell ffmpeg to do it.
[15:57:20 CET] <vexii> what flag?
[15:58:01 CET] <J_Darnley> http://ffmpeg.org/ffmpeg-filters.html#crop http://ffmpeg.org/ffmpeg-filters.html#pad-1 http://ffmpeg.org/ffmpeg-filters.html#scale-1
[15:59:21 CET] <vexii> and i can't get it to auto scale it ?
[15:59:43 CET] <J_Darnley> Scale it to what exactly?
[16:00:04 CET] <J_Darnley> there is no "make this work" option
[16:00:11 CET] <vexii> divisible by 2
[16:00:43 CET] <vexii> i pref not having to chrop pad or scale as the picture is the size i need
[16:01:19 CET] <J_Darnley> WTF?  If you can't change the frame size then you can't make the width divisible by 2
[16:04:34 CET] <vexii> prefer is on the same as can't. but this is just going to be a bad edge case
[16:04:45 CET] <vexii> thanks for the time.
[16:22:32 CET] <eghdk> J_Darnley: Thanks. I just wanted to check with a group of people familiar with it until I dumped some time into it
[17:57:34 CET] <Prelude2004c> hey everyone good day.. anyone know what a 406 error means ?
[17:58:01 CET] <Prelude2004c> using vlc i can pull the url but when i try with ffmpeg i get : [http @ 0x2566100] HTTP error 406 Not Acceptable
[17:58:01 CET] <Prelude2004c> [hls,applehttp @ 0x255e240] Failed to open segment of playlist 0
[18:05:33 CET] <jkqxz> Prelude2004c:  406 means the "Accept" header on your HTTP request does not include whatever type the server you are connecting to wanted to send, so it decided to give you an error instead.
[18:06:01 CET] <Prelude2004c> ic.. ok investigating.. thank you
[18:06:13 CET] <jkqxz> (If you want a more ffmpeg-oriented answer than that then you'll need to provide more information, such as a complete log...)
[18:58:02 CET] <llogan> http://ffmpeg.gusari.org/viewtopic.php?f=11&t=2739&p=8224#p8223
[18:58:48 CET] <llogan> poor bastard. he's hopeless.
[19:05:36 CET] <J_Darnley> Apple is still making My First Computers(TM) I see
[19:06:21 CET] <bencoh> more than ever
[19:06:31 CET] <bencoh> but not just apple (and we're not friday yet) :p
[19:08:13 CET] <J_Darnley> Oh yes.
[19:08:35 CET] <J_Darnley> Can't forget Microsoft's two latest offerings.
[19:09:23 CET] <furq> .... Notice the ./ before the ffmpeg: No such file or directory
[19:09:27 CET] <furq> that's the saddest thing i've ever seen
[19:11:29 CET] <llogan> Just need to find a ffgui with one button for these users. it works by analyzing search history and social media engineering.
[19:13:35 CET] <axc1298> hi. i read that with 'ffmpeg -i' i can list some information about a video file, including the resolution. i was wondering if there is a way i can return just the resolution for a list of files, not all the other information that comes with -i
[19:14:49 CET] <llogan> ffprobe -v error -of default=nw=1 -select_streams v:0 -show_entries stream=height,width input.foo
[19:14:49 CET] <J_Darnley> grep?
[19:14:57 CET] <J_Darnley> or ffprobe ^^
[19:15:18 CET] <llogan> another zample: https://trac.ffmpeg.org/wiki/FFprobeTips#WidthxHeight
[19:16:15 CET] <axc1298> thanks, that's cool llogan
[20:07:39 CET] <axc1298> J_Darnley: i want it in the form 123x456 instead of width=320 height=240 so i ended up using both ffprobe and grep lol
[20:10:54 CET] <llogan> axc1298: the example in the link i provided will also provide 123x456
[20:19:04 CET] <axc1298> llogan: nice. i see it there at the bottom now
[20:57:33 CET] <jonah> Is it possible to add subtitles to a video with ffMpeg and ffProbe?
[20:58:36 CET] <J_Darnley> Why would ffprobe play any role?
[20:58:42 CET] <J_Darnley> Otherwise yes.
[21:07:10 CET] <jonah> ok, thanks
[21:08:38 CET] <J_Darnley> That was it?  No "how" or any other followup questions?
[21:19:17 CET] <Mavrik> :))
[21:22:41 CET] <thebombzen> haha
[21:29:23 CET] <axc1298> so i put the recommendations in that link into a script that shows resolution for a video file. i'm really bad at bash though. if i have a bunch of video files, and each one is in its own directory within the same parent directory, is there a way to run this on them? http://paste.debian.net/416090
[21:29:52 CET] <axc1298> i was thinking i could use it with ls somehow
[21:30:34 CET] <furq> for f in */*.avi
[21:30:55 CET] <J_Darnley> find and its -exec option
[21:31:21 CET] <furq> you won't be able to pass that to exec
[21:31:47 CET] <furq> i guess you could do it with xargs but if each file is one directory deep then you might as well use */*
[21:32:03 CET] <axc1298> so for f in */*.avi, run that script?
[21:32:14 CET] <furq> yeah
[21:32:18 CET] <axc1298> cool
[21:32:18 CET] <furq> and change $* to $f
[21:32:45 CET] <J_Darnley> find . -type f -exec bash script.sh {} ';'
[21:33:36 CET] <furq> that's the kind of talk that will get you kicked out of shell script club
[23:09:13 CET] <poprop> hello, does the FFmpeg's header/libs win32 binary distribution have the DXVA2 decoding option compiled in? "avcodec_find_decoder_by_name("h264_dxva2")" fails.
[23:16:50 CET] <J_Darnley> Who's binary?
[23:16:50 CET] <J_Darnley> FFmpeg (the project) doesn't ship any
[23:17:53 CET] <poprop> hello J_Darnley: "https://www.ffmpeg.org/download.html#build-windows" which leads to: "https://ffmpeg.zeranoe.com/builds/"
[23:18:21 CET] <J_Darnley> then yes I think they do have dxva
[23:18:49 CET] <poprop> hum then i must be doing something wrong, thanks for your help it clears things up!
[23:21:30 CET] <jkqxz> poprop:  DXVA2 is a hwaccel, not a standalone decoder.  You want to get the normal ffmpeg decoder ("h264") and then attach the hwaccel to it.
[23:24:33 CET] <poprop> this explains a lot, i will attempt this, thanks. Should I initialize the dxva2 hwaccel using the "ffmpeg_dxva2.c"/"dxva2_init" helper function?
[23:27:14 CET] <poprop> it seems it expects a "DXVA2Context" through the "opaque" field of the AVCodecContext which can be null.
[23:30:04 CET] <jkqxz> You want to do something like ffmpeg_dxva2.c does, yes (that file is basically the example of how to set up the dxva2 hwaccel, for the hwaccel-generic parts you might need to look at ffmpeg.c).
[23:30:50 CET] <poprop> great, thank you very much jkqxz, will do.
[23:31:32 CET] <poprop> bye everyone, thanks for the help.
[23:38:16 CET] <Cyber_Akuma> Does it matter where I use the -threads argument in the command line? Can I use it anywhere within the arguments?
[23:38:30 CET] <J_Darnley> Yes and also yes
[23:39:11 CET] <J_Darnley> It is a codec option so it affects each codec that you use it with.
[23:41:08 CET] <Cyber_Akuma> So, if I use it as my first argument before even -i for the input file, will it apply to everything
[23:41:08 CET] <Cyber_Akuma> ?
[23:41:48 CET] <J_Darnley> ffmpeg -threads 1 -i INPUT OUTPUT is not the same as ffmpeg -i INPUT -threads 1 OUTPUT
[23:42:16 CET] <J_Darnley> To answer your specific question: absolutely not
[23:42:32 CET] <Cyber_Akuma> I see, what is the difference? The first one will only affect the imput codec, not the output one?
[23:42:40 CET] <J_Darnley> yes
[23:43:06 CET] <Cyber_Akuma> So I should use it before my output arguments if I want it to use multithreaded encoding
[23:43:18 CET] <J_Darnley> yes
[23:43:18 CET] <furq> you normally don't need to specify threads at all unless you're trying to free up cores
[23:43:30 CET] <Cyber_Akuma> It seems to default to 1 thread
[23:43:30 CET] <furq> most commonly used encoders will automatically use multithreading
[23:43:33 CET] <J_Darnley> (a good codec will autodetect though)
[23:44:35 CET] <furq> are you by any chance using libvpx
[23:44:48 CET] <Cyber_Akuma> Actually, I am using the ffmpeg that MeGui installed
[23:44:54 CET] <Cyber_Akuma> oh, for input, yes
[23:45:01 CET] <furq> no i mean as an encoder
[23:45:11 CET] <Cyber_Akuma> I am converting some mp4 files to webm for embedding in web pages
[23:46:03 CET] <Cyber_Akuma> "-c:v libvpx"
[23:46:54 CET] <furq> getting multithreading working properly with libvpx is a pain
[23:47:16 CET] <Cyber_Akuma> I see
[23:47:40 CET] <TD-Linux> in particular, the main way to do multithreaded encodes is tiles
[23:47:42 CET] <furq> if it's not one of those sites which only hosts webm then you might as well just use mp4 for the web
[23:48:00 CET] <furq> assuming it's h264/aac
[23:48:02 CET] <TD-Linux> however VP8 doesn't have tiles
[23:48:31 CET] <TD-Linux> the other main way is to split your video and encode sections separately, unfortunately neither libvpx nor ffmpeg will do that for you
[23:48:31 CET] <furq> vp8 has --token-parts
[23:48:32 CET] <Cyber_Akuma> I do use the mp4 in most sites that allow it
[23:48:58 CET] <furq> i'm not sure how that maps to ffmpeg though, i'm just looking at the webm docs
[00:00:00 CET] --- Thu Mar 17 2016