[Ffmpeg-devel-irc] ffmpeg.log.20151115

[burek]

[04:46:24 CET] <lizzi_> howdy
[04:47:03 CET] <lizzi_> question about building ffmpeg
[04:47:55 CET] <lizzi_> is there an actual patch?
[04:48:03 CET] <lizzi_> prepare() {
[04:48:04 CET] <lizzi_> cd ${pkgname%-full}-$pkgver
[04:48:04 CET] <lizzi_> patch -p1 -i ../ffmpeg-2.8.1-libvpxenc-remove-some-unused-ctrl-id-mappings.patch
[04:48:04 CET] <lizzi_> }
[04:48:19 CET] <lizzi_> see this says there is a patch
[04:48:25 CET] <lizzi_> but where is the patch
[04:54:19 CET] <waressearcher2> lizzi_: hallo
[04:54:49 CET] <lizzi_> hallo
[04:55:17 CET] <waressearcher2> lizzi_: wie geht's ?
[04:55:48 CET] <lizzi_> sehr gut
[04:55:53 CET] <lizzi_> something
[04:56:10 CET] <lizzi_> unt sie?
[04:56:20 CET] <waressearcher2> es geht's
[04:56:59 CET] <lizzi_> i was in germany as a soldier in the late 80's and though i am pennsylvania dutch, i dont speak german
[04:57:20 CET] <lizzi_> though my dads older brothers did
[04:58:45 CET] <lizzi_> my aunt margaret was born in germany
[04:59:04 CET] <lizzi_> her brothe ludwig live north of heildelberg
[05:01:02 CET] <lizzi_> Ich spreche kein Deutsch, aber meine Vatis älteren Brüder zu verwende
[05:02:16 CET] <lizzi_> i was stationed in nueremburg at the 98th gen hospital before it closed
[05:04:28 CET] <lizzi_> ==> Starting prepare()&
[05:04:28 CET] <lizzi_> patch: **** Cant open patch file &/ffmpeg-2.8.1-libvpxenc-remove-some-unused-ctrl-id-mappings.patch : No such file or directory
[05:04:28 CET] <lizzi_> ==> ERROR: A failure occurred in prepare().
[05:04:28 CET] <lizzi_> Aborting&
[05:04:28 CET] <lizzi_> ==> ERROR: Makepkg was unable to build ffmpeg-full.
[05:04:29 CET] <lizzi_> ==> Restart building ffmpeg-full ? [y/N]
[05:04:31 CET] <lizzi_> ==> ------------------------------------
[05:04:47 CET] <lizzi_> so is there an actual patch?
[05:35:56 CET] <bencc> anYc: I'll try to reproduce it and share the video. thanks
[05:41:47 CET] <lizzi_> hello
[07:26:25 CET] <koz_> I have a video with two audio tracks, and I only want the second one. What flag(s) do I have to give to ffmpeg to ensure this?
[07:31:35 CET] <furq> -map 0:a:1
[07:32:16 CET] <koz_> furq: Thanks!
[07:33:38 CET] <koz_> ffmpeg doesn't seem to like this very much.
[07:33:46 CET] <koz_> Let me just paste you my whole command.
[07:34:30 CET] <koz_> ffmpeg -i in.avi -map:0:a:1 -codec:a opus -b:a 128k -codec:v vp9 -b:v 1.5M -crf 10 -cpu-used 8 -threads 4 out.mkv
[07:35:04 CET] <furq> -map 0:a:1, not -map:0:a:1
[07:35:15 CET] <furq> you probably also need -map 0:v before that
[07:35:38 CET] <furq> and i expect the video codec should be libvpx-vp9
[07:37:48 CET] <koz_> furq: OK. Why libvpx-vp9 and not just vp9?
[07:38:36 CET] <furq> don't ask me
[07:38:40 CET] <furq> that's just what the encoder's called
[07:38:56 CET] <koz_> OK, cool, thanks. That's working great now. :)
[10:37:22 CET] <AndrewMock> Does anybody know if libavcodec has Atmos support?
[11:04:58 CET] <durandal_1707> what's atmos?
[11:42:12 CET] <AndrewMock> Object-based audio
[11:42:34 CET] <AndrewMock> Dolby brand of it at least. DTS has DTS:x which they may open-source.
[11:43:52 CET] <AndrewMock> Instead of channel-based audio, the raw noises and their locations are recorded. The mix is generated on-the-fly by the decoder.
[11:44:16 CET] <AndrewMock> So what that implies is that the decoder can have a 13.6 channel output in theory.
[11:44:23 CET] <AndrewMock> Anything you want.
[11:45:22 CET] <AndrewMock> Mission Impossible: Rogue Nation [2015] used it a little bit. To add overhead channels.
[11:45:51 CET] <furq> as far as i can tell it supports it as far as being able to discard it from truehd streams
[11:51:07 CET] <AndrewMock> If I wanted to be in the loop on the development for that, how would I do that
[16:01:15 CET] <jasom_> hi guys, is it possible to add exif metatags into video thumbnails generated by ffmpeg? I want to add userComment  into that pictures
[16:04:06 CET] <jasom_> I found shell tools such as"jhead" or "Exiv2" but I would like to add custom tags directly with FFMPEG
[16:05:37 CET] <jasom_> any hint or link to tutorial would be helpfull
[16:53:04 CET] <PhoenixBR> Hi guys, how can I convert uyvy422 to yuv422p?
[16:53:21 CET] <PhoenixBR> ffmpeg -f rawvideo -vcodec rawvideo -s 720x576 -r 25 -pix_fmt uyvy422 -i src6_ref__625.yuv -s 720x576 -vcodec rawvideo -pix_fmt yuv420p out.yuv
[16:53:26 CET] <PhoenixBR> Is this correct?
[16:53:45 CET] <c_14> should be fine
[16:54:18 CET] <PhoenixBR> any lost in this corvesion?
[16:54:42 CET] <PhoenixBR> -vcodec rawvideo -> -vcodec rawvideo
[16:55:13 CET] <klaxa> you are doing uyvy422 to yuv420p, you'll lose some information i think
[16:59:43 CET] <c_14> h
[16:59:46 CET] <c_14> Oh, right
[16:59:53 CET] <c_14> You wanted yuv422p, use -pix_fmt yuv422p
[17:16:20 CET] <PhoenixBR> and for uyvy422 -> yuv422p conversion, any lost information?
[19:33:43 CET] <yumbox> Why does ffmpeg write the date as UTC 1904-01-01 00:00:00 ?
[19:35:50 CET] <JEEB> I think the original idea was to generate bit-exact files and not leave traces for possible privacy concerns
[19:36:16 CET] <yumbox> ah, interesting.
[19:38:03 CET] <Fyr> guys, does ffmpeg support .WV for input?
[19:38:09 CET] <yumbox> how can I turn it back on again?
[19:38:21 CET] <Fyr> I'm trying to convert it into WAV or FLAC. =(
[19:38:31 CET] <JEEB> Fyr: have you tried? :P
[19:38:49 CET] <Fyr> *.wv: Invalid data found when processing input
[19:38:50 CET] <JEEB> if ffmpeg -i input returns something meaningful there's a nice chance of it working
[19:38:53 CET] <JEEB> uhh
[19:38:59 CET] <JEEB> a single file
[19:39:00 CET] <JEEB> :P
[19:39:10 CET] <JEEB> no different from any other use case with FFmpeg
[19:39:13 CET] <Fyr> the file starts with MZP.
[19:39:35 CET] <JEEB> or was the * you hiding the actual file name?
[19:39:44 CET] <JEEB> and you're not giving ffmpeg *.wv
[19:39:57 CET] <Fyr> .\1.wv: Invalid data found when processing input
[19:40:09 CET] <Fyr> ffmpeg version N-76347-gdd36749
[19:40:17 CET] <JEEB> just pastebin the full command line and terminal output and link it here
[19:40:35 CET] <Fyr> I was hiding the fact I'm using PowerShell. =)
[19:40:51 CET] <JEEB> doesn't matter
[19:41:00 CET] <JEEB> as long as you can show the exact command line and the terminal output
[19:41:09 CET] <JEEB> pastebin it and link here
[19:41:25 CET] <JEEB> shouldn't be hard to do because powershell is less retarded than cmd.exe
[19:41:48 CET] <Fyr> JEEB, http://pastebin.com/w1YKGTCb
[19:42:14 CET] <JEEB> and this file plays in something else?
[19:42:15 CET] <Fyr> but it's more retarded than bash.
[19:42:31 CET] <Fyr> it is being played right now with AIMP3.
[19:42:48 CET] <JEEB> feel free to create a bug report with a sample on the trac
[19:43:11 CET] <Fyr> the sample is of 300 Mb.
[19:43:25 CET] <JEEB> try cutting it and see that it still plays elsewhere and see if you can replicate
[19:43:33 CET] <Fyr> how do I cut it?
[19:43:38 CET] <Fyr> ffmpeg doesn't read it!
[19:43:52 CET] <JEEB> there's plenty of dd binaries for windows
[19:44:21 CET] <JEEB> try with about 10MB at first
[19:45:03 CET] <ChocolateArmpits> you could do it with powershell and .net
[19:49:33 CET] <furq> you should probably run ffmpeg directly on the file and make sure it's not powershell
[19:49:49 CET] <furq> on account of it's probably powershell
[19:50:10 CET] <ChocolateArmpits> powershell should have no effect on it
[19:50:27 CET] <furq> "should"
[20:29:37 CET] <Soni> can I make apngs with ffmpeg?
[20:34:09 CET] <c_14> yes
[20:35:03 CET] <Soni> can firefox display 1080p apngs?
[20:36:07 CET] <JEEB> why don't you try?
[20:36:55 CET] <durandal_1707> Nope, maybe Firefox have apng plugin?
[20:38:14 CET] <durandal_1707> 1080p is slow and big with apng
[20:38:27 CET] <c_14> It works on my system.
[20:41:42 CET] <Soni> I mean like, without crashing
[20:43:32 CET] <Soni> nah it crashes >.<
[20:43:40 CET] <c_14> Doesn't here
[20:44:26 CET] <Soni> I'm on firefox nightly on linux
[20:44:56 CET] <Soni> also this is a 1080p 24fps video we're talking about
[20:47:21 CET] <Soni> ok so how do I downscale an APNG?
[20:47:31 CET] <Soni> a 1080p 24fps APNG...
[20:47:35 CET] <JEEB> use -vf scale
[20:47:43 CET] <JEEB> see ffmpeg-all.html for details/documentation
[21:18:39 CET] <Soni> what should I use to downscale 1350x1080 into 90x72?
[21:19:00 CET] <Mavrik> Downscale what? :)
[21:19:12 CET] <Soni> mp4 into apng
[21:19:20 CET] <fritsch> lol
[21:19:30 CET] <fritsch> one frame I suppose?
[21:19:36 CET] <fritsch> sws_fast_bilinear
[21:19:39 CET] <Mavrik> Ah, sorry, mixed up channels :)
[21:19:55 CET] <Soni> it's basically 90x72 upscaled to 1350x1080
[21:20:02 CET] <Soni> and I need to downscale it back
[21:20:10 CET] <Soni> but I can't get it quite right
[21:20:13 CET] <JEEB> same thing, vf scale
[21:20:46 CET] <Soni> I'm trying ffmpeg -i junior-senior_move-your-feet_1080p.mp4 -vf scale -s 90x72 -sws_flags <already tried all algos> js-myf-tiny.apng
[21:21:20 CET] <JEEB> uhh, that won't work of course
[21:21:40 CET] <JEEB> https://www.ffmpeg.org/ffmpeg-all.html#Examples-97
[21:21:59 CET] <JEEB> scale=w=90:h=72 is the simplest for a specific size :P
[21:22:28 CET] <JEEB> and -s is a shorthand to -vf scale but with less possibilities so you shouldn't use it any more
[21:23:02 CET] <Soni> still has wrong colors
[21:23:12 CET] <JEEB> also if  your ffmpeg is built with the zimg library you can use the zscale filter, which is better
[21:24:47 CET] <Soni> how do I check that?
[21:25:30 CET] <JEEB> it outputs the configuration line at the top when you run ffmpeg, right?
[21:25:50 CET] <JEEB> if it's got --enable-zimg or --enable-zscale it should be enabled and linked in
[21:26:27 CET] <Soni> it doesn't
[21:26:49 CET] <Soni> meh why's it off...
[21:27:17 CET] <Soni> I think I'll manually scale the 1080p apng >.<
[21:27:45 CET] <Soni> (well not quite manually... more like write a program to do it for me)
[21:28:07 CET] <Soni> if I can't get it to work at least
[21:28:36 CET] <Soni> how do I set the scaling method?
[21:29:18 CET] <JEEB> as far as I can see sws_flags is the correct option for swscale, zscale has its own option as it has nothing to do with swscale
[21:29:30 CET] <JEEB> although you're setting it on the output side
[21:29:36 CET] <JEEB> while I think it's an input option
[21:29:45 CET] <JEEB> oh, available for both
[21:42:58 CET] <PhoenixBR> Hi there guys!
[21:43:07 CET] <waressearcher2> PhoenixBR: hallo
[21:43:39 CET] <waressearcher2> PhoenixBR: wie geht's ?
[21:44:50 CET] <PhoenixBR> waressearcher2: gut! But I don't speak Deutsch unfortunately
[21:44:59 CET] <PhoenixBR> waressearcher2: xD
[21:45:12 CET] <PhoenixBR> Well, here I am with other question. So, take a sit and follow me.
[21:45:55 CET] <PhoenixBR> after raw YUV uyvy422 -> raw YUV yuv422p conversion, I would like to know the color space of the frames
[21:47:11 CET] <JEEB> wat
[21:47:23 CET] <JEEB> both are the same raw 4:2:2 YCbCr
[21:47:43 CET] <JEEB> one is mixed planar and packed
[21:47:47 CET] <JEEB> the other is pure planar
[21:47:53 CET] <PhoenixBR> but I converted uyvy422 to yuv420
[21:48:00 CET] <PhoenixBR> ah sorry, I typed wrong
[21:48:18 CET] <PhoenixBR> uyvy422 -> yuv420p
[21:48:54 CET] <PhoenixBR> then I opened the YUV yuv420p file in matlab using this code: http://pastebin.com/A1R4jiu1
[21:49:13 CET] <PhoenixBR> that gives me Y, U and V matrix
[21:49:20 CET] <JEEB> ok, so you changed the type the data is packaged and made it 4:2:0 (so instead of having chroma for every second (luma) sample on every line, you now have one chroma sample for 2x2 area of luma samples
[21:50:40 CET] <PhoenixBR> but can I accept these YUV matrix are YCbCr ?
[21:51:25 CET] <JEEB> yes, but unless you know the original colorimetry that's all you know
[21:51:52 CET] <JEEB> I mean, all "YUV" data in digital video is YCbCr, it's just an old colloquialism that it's called "YUV"
[21:52:13 CET] <JEEB> YUV was limited to analog space, this is digital
[21:52:44 CET] <PhoenixBR> hum, get it
[21:53:14 CET] <PhoenixBR> well, in description of the data base, says: "Each line is in multiplexed 4:2:2 component video format as follows:    Cb Y Cr Y ...    720 Y bytes per line    360 Cb bytes per line    360 Cr bytes per line "
[21:53:43 CET] <JEEB> yeah, but that says nothing about the colorimetry (BT.601 or BT.709 or whatever else)
[21:53:55 CET] <JEEB> usually SD stuff you can kind of expect to be around BT.601
[21:54:06 CET] <PhoenixBR> hum
[21:54:09 CET] <JEEB> but that's an assumption, and this is why modern video formats have metadata
[21:54:23 CET] <JEEB> so you can write down the colorimetry values
[21:54:33 CET] <JEEB> of course, colorimetry only matters when you are converting that YCbCr to something
[21:54:37 CET] <JEEB> (not YCbCr)
[21:54:49 CET] <JEEB> (or to another YCbCr colorimetry, yes)
[21:54:55 CET] <JEEB> (which usually means an RGB step in the middle)
[21:55:17 CET] <PhoenixBR> So, so it's reasonable trust on this assumption and consider this YUV matrix my YCbCr matrix
[21:55:27 CET] <JEEB> yes
[21:55:36 CET] <PhoenixBR> nice
[21:55:53 CET] <JEEB> what kind of YCbCr is what you don't know, but as long as you don't try to convert the data you should be fine
[21:56:12 CET] <PhoenixBR> ok
[21:56:47 CET] <PhoenixBR> I just want to run a SSIM (image quality) algorithm on the frames
[21:57:05 CET] <PhoenixBR> and it uses the y cb cr values
[21:57:43 CET] <JEEB> if you just pass it through video encoders and compare or whatever, that's OK since all your data should be in the same colorspace/-metry and you shouldn't have to convert it to anything
[21:57:47 CET] <JEEB> just note that SSIM is not quality
[21:57:53 CET] <JEEB> it's just a metric
[21:58:10 CET] <PhoenixBR> exacly :)
[21:58:23 CET] <PhoenixBR> that measures quality
[21:58:41 CET] <fritsch> not really
[21:58:54 CET] <fritsch> but you can use it to "measure" quality
[21:59:04 CET] <fritsch> if you compute the distance to a groundtruth file or something
[21:59:09 CET] <Mavrik> JEEB, what do the colormetry triplets actually do/
[21:59:10 CET] <fritsch> but it does not say "it's better"
[21:59:11 CET] <Mavrik> ?
[21:59:15 CET] <PhoenixBR> yeah
[21:59:57 CET] <JEEB> Mavrik: they control the parameters that are then used in conversion of the content to various other colorspaces
[22:00:00 CET] <PhoenixBR> nice guys! You helped me a lot!
[22:00:15 CET] <JEEB> zimg/zscale handles those rather well
[22:00:18 CET] <Mavrik> JEEB, so e.g. conversion to RGB for display on a panel?
[22:00:21 CET] <JEEB> yes
[22:00:38 CET] <JEEB> with HEVC you get even more metadata available (the parameters of the mastering screen)
[22:00:41 CET] <Mavrik> I usually didn't notice much difference if those were omitted on SD/HD content
[22:00:49 CET] <Mavrik> Are the players actually listening to them?
[22:00:55 CET] <JEEB> many are by now
[22:01:10 CET] <JEEB> but usually SD is BT.601'ish and HD is BT.709'ish
[22:01:21 CET] <JEEB> so the random guess goes right if they are omitted
[22:01:34 CET] <JEEB> usually thankfully I've seen the values be filled in the content I've seen
[22:02:01 CET] <Mavrik> I've mostly seen them too, still not sure why there are necessary.
[22:02:14 CET] <Mavrik> I guess because there are different matrices of how to do the YCbCr convertion?
[22:02:18 CET] <JEEB> yes
[22:02:21 CET] <fritsch> yes
[22:02:29 CET] <JEEB> also f.ex. in Japanese DTV SD is BT.709 as well
[22:02:37 CET] <JEEB> if you go by guessing you *will* get that wrong
[22:03:05 CET] <JEEB> (also UHDTV is limited to BT.2020)
[22:03:31 CET] <Mavrik> Ah, blah.
[22:03:38 CET] <Mavrik> Why the change in HD content?
[22:03:50 CET] <Mavrik> Meaning, why not use BT601 everywhere?
[22:03:59 CET] <JEEB> BT.601 was not based on sRGB, BT.709 is
[22:05:02 CET] <Mavrik> Also, if you miss the autodetect (e.g. display BT.601 when the content is 709), is there a visual check you can do? Noticable color shift?
[22:05:33 CET] <JEEB> in case of BT.601/BT.709 the change is not big but I think there was a shift in greens etc
[22:05:38 CET] <Mavrik> (Sorry for dumb questions, documentation on that is rather... scarce and not really evening reading material.)
[22:05:57 CET] <JEEB> BT.2020 is on the other hand a widening of the gamut etc so that will be much bigger
[22:19:15 CET] <Soni> can I make ffmpeg use a palette?
[22:21:29 CET] <c_14> Check the paletteuse filter
[22:24:53 CET] <Soni> how do I use a 16 color palette?
[22:26:18 CET] <c_14> Create a 16x16px image and put a color on every row?
[00:00:00 CET] --- Mon Nov 16 2015