[Ffmpeg-devel-irc] ffmpeg.log.20190717

[burek]

[00:26:19 CEST] <nine_milli> blb
[02:18:11 CEST] <gschanuel9> night!
[02:18:11 CEST] <gschanuel9> i'm trying to join 15 mp4 videos into a matrix 3x5. I've found some command lines to do a 2x2
[02:18:44 CEST] <furq> gschanuel: https://ffmpeg.org/ffmpeg-filters.html#xstack
[02:20:44 CEST] <gschanuel> very informative indeed. think I got it :)
[02:42:15 CEST] <gschanuel> actually, i thought i'd got it, but didn't
[02:42:19 CEST] <gschanuel> ffmpeg -i 09JtDCQ5.mp4 -i 9IDNRtPP.mp4 -i bO_HGIwN.mp4 -i c2LRRnjO.mp4 -i CfK13HXE.mp4 -i EOTAq9L9.mp4 -i Fa+IueML.mp4 -i lPK8LXKp.mp4 -i MLChV65X.mp4 -i O0xIVcFM.mp4 -i PPiVss5k.mp4 -i SRLpxv7x.mp4 -i tXI6sMKq.mp4 -i zC1a+ig6.mp4 -i zzultimo2.mp4 -i zzultimo.mp4 -filter_complex "xstack=inputs=15:layout=w0_h0|1_0|2_0|0_1|1_1|2_1|0_2|1_2|2_2|0_3|1_3
[02:42:19 CEST] <gschanuel> |2_3|0_4|1_4|2_4"
[02:42:55 CEST] <gschanuel> it failed with [Parsed_xstack_0 @ 0x5586369c2500] Failed to configure output pad on Parsed_xstack_0
[02:43:07 CEST] <gschanuel> Error while processing the decoded data for stream #14:0
[02:43:25 CEST] <gschanuel> does that mean my #14th video was corrupted?
[02:57:28 CEST] <kepstin> gschanuel: please pastebin the *complete* output (preferably with -v verbose to debug filterchain stuff)
[03:19:15 CEST] <gschanuel> https://gist.github.com/a46723508259bf6a75916633f763e86e
[03:20:43 CEST] <gschanuel> https://gist.github.com/f5679ab7671ec3adcef88053e4e50515
[03:23:15 CEST] <gschanuel> sorry.. damn.. i'm bit high already, cold night ask some alcool XD
[03:25:03 CEST] <gschanuel> wanna make a meme for a friend
[03:25:38 CEST] <klaxa> SRLpxv7x.mp4 seems to be b0rked?
[03:25:59 CEST] <klaxa> what does ffprobe show for it? (pastebin again)
[03:26:52 CEST] <gschanuel> https://gist.github.com/7282458e9f28dfc06debe8b7b4595ce8
[03:27:03 CEST] <gschanuel> ha! i was faster now huh!
[03:29:19 CEST] <gschanuel> i believe this is the first time I really mean lol
[03:33:33 CEST] <gschanuel> forget it.. i'm not even reading the outputs .. not able to rationalize much atm..
[03:38:56 CEST] <DHE> I feel like this is a common enough thing that there should be a "ystack" filter or something that just takes width, height, and auto-assigns streams left-to-right, then top-to-bottom.
[03:40:20 CEST] <klaxa> i can't find anything obviously wrong...
[03:47:29 CEST] <MikeJoel> is there a way to rotate the video - took some mp4 videos off my phone and for some reason they are all on their sides :/
[03:51:03 CEST] <nine_milli> blb
[03:55:00 CEST] <MikeJoel> sorry lost power
[03:55:14 CEST] <MikeJoel> I had asked about rotating video
[03:55:25 CEST] <furq> is there some way i'm missing of getting a color source in rgb without having to convert it afterwards
[03:56:20 CEST] <furq> the least stupid way i can think of is color=white,format=rgb24,drawbox
[03:56:23 CEST] <furq> which seems pretty stupid
[04:07:00 CEST] <klaxa> have something (`yes`?) write raw octets and use -f rawvideo -pix_fmt rgb24 ?
[04:07:17 CEST] <klaxa> and -s and -r obv.
[04:07:29 CEST] <furq> funnily enough i am already doing that for the palette in this script
[04:07:38 CEST] <furq> so that would work
[04:07:58 CEST] <klaxa> sounds like the next most reasonable thing to do
[04:08:01 CEST] <furq> well
[04:08:08 CEST] <furq> except for the fact that stdin is already occupied
[04:08:24 CEST] <klaxa> named pipes? :>
[04:08:45 CEST] <furq> that's less than ideal
[04:09:53 CEST] <furq> i'm surprised this hasn't come up before honestly
[04:30:07 CEST] <MikeJoel> Is there a way to rotate a video while converting?
[05:18:10 CEST] <furq> doh
[05:18:18 CEST] <furq> so apparently the issue i was having was an entirely different part of the command
[05:18:33 CEST] <furq> apparently yuvj444p to gray fucks up the range
[05:19:50 CEST] <furq> MikeJoel: if it's mp4 then you probably won't need to reencode
[05:19:55 CEST] <furq> mp4 has rotation metadata you can set
[05:20:21 CEST] <furq> or which you can delete because if these are off a phone then that metadata might already be set wrong
[05:20:48 CEST] <furq> you can check with ffprobe and then set it with -metadata:s:v:0 rotate=90
[05:29:50 CEST] <kepstin> DHE: i have part of the prototyping done for a filter that does that. (take n inputs and an output video size, scale+tile the inputs into a grid). i should finish that some time...
[05:44:52 CEST] <MikeJoel> furq: thanks
[06:49:54 CEST] <kepstin> https://www.kepstin.ca/dump/Screenshot%20from%202019-07-17%2000-45-43.png still needs work, it doesn't actually generate output frames yet :)
[09:10:01 CEST] <MoziM> why are there fps values that are floating numbers?
[09:28:01 CEST] <MoziM> https://code.likeagirl.io/finding-out-im-autistic-at-30-e5754ce9462a?source=collection_home---4------0-----------------------
[09:55:36 CEST] <durandal_1707> gschanuel: did you managed to do xstack into 3x5 matrix?
[10:31:50 CEST] <MoziM> woops wrong channel sorry
[12:26:13 CEST] <suryajagtap> how to stream a local file using ffmpeg
[13:44:46 CEST] <lain98> i'm trying to transcode a video to change pix_fmt from yuv420p to nv12. the command runs fine but the output file still reports yuv420p. I used ffmpeg -i input -pix_fmt nv12 output. ffmpeg -i output still reports yuv420p
[13:46:39 CEST] <Mavrik> lain98: what are you transcoding to?
[13:46:44 CEST] <Mavrik> Most video formats don't support nv12
[13:46:58 CEST] <Mavrik> or, more accurately, most encoders.
[13:49:01 CEST] <lain98> x264
[13:49:12 CEST] <lain98> Mavrik,
[13:49:21 CEST] <lain98> x264 mp4
[13:51:30 CEST] <BtbN> h264 does not have a pixel format
[13:51:43 CEST] <BtbN> It's the decoder that decides what pixel format to put the decoded data in
[13:52:05 CEST] <JEEB> hardware decoders usually utilize nv12, while sw decoders historically use the fully planar formats (yuv420p etc)
[13:52:28 CEST] <Mavrik> Hmm, good point.
[13:52:35 CEST] <JEEB> esp. true with H.264. so when you decode with swdec H.264 you will get yuv420p. which has the same data as nv12
[13:52:51 CEST] <Mavrik> I may have explained that wrong: H.264 has it's own way of storing data and "NV12" doesn't make sense in that world
[13:53:03 CEST] <JEEB> nv12 just is half-packed, (luma is same as yuv420p, chroma interleaved) while yuv420p has all planes separate :P
[13:53:07 CEST] <lain98> could i use mkv
[13:53:13 CEST] <JEEB> the container really doesn't matter
[13:53:39 CEST] <JEEB> lain98: H.264 codes 4:2:0 content and if you get nv12 or yuv420p out of a decoder depends 100% on what the decoder does; the actaul content is the same
[13:54:01 CEST] <JEEB> lain98: if you need nv12 for some part of the process that you're doing then you can always do a conversion process in the middle if needed
[13:54:04 CEST] <lain98> okay
[13:54:06 CEST] <lain98> thanks
[13:54:07 CEST] <JEEB> after all, it's just the location of the data
[13:54:42 CEST] <JEEB> NV12 has it [luma] [CrCbCrCbCr...] while yuv420p is [luma] [CrCrCr...] [CbCbCb...]
[13:54:45 CEST] <JEEB> :P
[13:54:56 CEST] <JEEB> GPU based things seem to like the former
[13:55:55 CEST] <JEEB> (also I think the order is actually YCbCr, but details~)
[14:24:45 CEST] <pomaranc> is there any way to use frame metadata from ocr to create a text subtitle track?
[14:30:06 CEST] <DHE> from ffmpeg-all I rather doubt it without doing a custom application
[14:30:48 CEST] <pomaranc> yeah, that's what I thought too after reading it
[14:34:28 CEST] <JEEB> yea, you'd need the AVSubtitle (image) -> AVFrame (tesseract) -> AVSubtitle (text) stuff to be around
[14:35:36 CEST] <JEEB> the first part is already there in the sub2video logic in ffmpeg.c
[14:35:46 CEST] <JEEB> which plasters the AVSubtitleRectangles onto a canvas
[14:35:54 CEST] <JEEB> so you can then feed them to a video filter chain
[14:35:55 CEST] <JEEB> buut
[14:36:15 CEST] <JEEB> then you need something to read the results of that and convert them to text based AVSubtitles based on the metadata
[14:39:50 CEST] <durandal_1707> asked numerous times and answered in myriad variations by JEEB
[14:41:08 CEST] <kurosu> oh wow imm5, what a weird beast
[14:42:01 CEST] <kurosu> durandal_1707: does the "thing" effectively allows to switch between h264 and h265 on a frame basis? is it intra-only or ?
[14:42:19 CEST] <durandal_1707> it is not intra only
[14:42:30 CEST] <kurosu> otherwise, I have no idea how the codec cannot be constant (but why signal it on the frame header?) through a gop ?
[14:43:04 CEST] <kurosu> err, wrong window |-[
[14:53:14 CEST] <pomaranc> JEEB: thank you
[14:53:22 CEST] <pomaranc> that's useful info
[16:45:04 CEST] <dodgepong`work> Hi all. Does anyone know anything about hardware decoding of webm files that have an alpha channel?
[16:45:58 CEST] <nine_milli> blb
[16:46:36 CEST] <durandal_1707> webm is dead
[16:47:01 CEST] <dodgepong`work> What should people be using instead for video with alpha transparency that is easy to work with?
[16:47:11 CEST] <dodgepong`work> And supports hardware decoding
[16:47:32 CEST] <DHE> webm is just a container. I assume you mean vp9 (the codec)
[16:48:09 CEST] <dodgepong`work> Well, unfortunately VP9 by itself doesnt support alpha, so Chrome decided to support alpha transparency in the webm container by adding a mono alpha stream
[16:48:18 CEST] <dodgepong`work> alongside the VP9 stream
[16:48:28 CEST] <DHE> oh that's funky...
[16:48:33 CEST] <dodgepong`work> Indeed
[16:48:37 CEST] <dodgepong`work> And yet, its still widely used
[16:48:38 CEST] <MoziM> how can a video have a bitrate of 0?
[16:49:05 CEST] <DHE> probably means the bitrate isn't measured
[16:49:17 CEST] <MoziM> why?
[16:49:41 CEST] <dodgepong`work> @durandal_1707 Why do you say webm is dead, and what do you suggest as an alternative?
[16:49:44 CEST] <DHE> because video is almost always VBR and hence difficult to measure without actually reading the whole file and calculating
[16:51:58 CEST] <MoziM> oh...
[16:52:37 CEST] <durandal_1707> dodgepong`work: webm is google product iiuc
[16:52:40 CEST] <MoziM> i guess my video player caches the bit rate when it encounters a new video
[16:52:49 CEST] <MoziM> so new videos would read 0
[17:13:46 CEST] <durandal_1707> dodgepong`work: for local stuff, i use nut container
[17:23:27 CEST] <dodgepong`work> @durandal_1707 does nut work with common editors and creation programs like After Effects
[17:24:53 CEST] <durandal_1707> deetwelve: i do not use such products, sorry
[17:25:01 CEST] <durandal_1707> dodgepong`work: ^
[17:25:20 CEST] <dodgepong`work> I see
[17:25:30 CEST] <dodgepong`work> Thanks for the info, I had never heard of nut before
[18:36:13 CEST] <sine0> hey guys, is it possible to record a radio stream in ffmpeg, like from stream.pls from the uk bbc that works in vlc network stream
[18:37:39 CEST] <durandal_1707> yes
[18:38:38 CEST] <sine0> I have tried ffpmeg -y -i bbc.co.uk/blah/stream.pls output.mp3
[18:38:49 CEST] <sine0> as a blog post mentioned, could you advance on that (it didnt work)
[18:39:01 CEST] <sine0> perhaps they work with headers or something...
[18:39:44 CEST] <durandal_1707> sine0: if you want help, pastebin actuall ffmpeg full output
[18:42:07 CEST] <sine0> https://pastebin.com/Q5XNix3U
[18:47:01 CEST] <durandal_1707> sine0: ffmpeg does not support playlist format yet (pls) so you need to download manually and extract http stream
[18:47:34 CEST] <durandal_1707> extract steam from pls file
[18:48:08 CEST] <c_14> sine0: if you open the pls file in a text editor there should be a url there, give that to ffmpeg
[18:49:19 CEST] <sine0> ok thanks
[18:49:43 CEST] <durandal_1707> or use mpv for playback, it can capture stream too
[18:49:57 CEST] <nine_milli> blb
[18:54:07 CEST] <CoreX> download the pls open in texteditor take link and paste into youtube-dl and let it save for you
[19:22:32 CEST] <Classsic> hi, somebody have this issue: when push rtsp to rtmp local server, the speed is greater than 1, and fps input it´s ok. but when push to public server, get the half speed on fps.
[19:22:53 CEST] <Classsic> this only happen on windows static build, on linux, work perfectly.
[19:24:20 CEST] <Classsic> is like windows throttle the bandwidht when push rtmp to public address.
[20:21:27 CEST] <sine0> Does anyone know if its possible to rip from netflix
[20:21:50 CEST] <sine0> i know it wouldnt be a popular thing to post on the internet as they are probably aggressive but is it possible
[20:21:58 CEST] <sine0> other than just a screen recorder
[20:22:11 CEST] <BtbN> It's copy protected. You can't screen record it.
[20:23:46 CEST] <durandal_1707> why are you asking here for ways to break laws?
[20:23:55 CEST] <sine0> good point it was just a thought
[20:24:01 CEST] <JEEB> sine0: technically it seems like it's possible since I see stream rips pop up on the internet, but don't ask me about the solutions :)
[20:24:12 CEST] <sine0> JEEB: thats what im saying fella
[20:24:26 CEST] <JEEB> keywords would probably be "widevine" and something else :P
[20:24:29 CEST] <BtbN> People usually use HDCP strippers and a capture card for that.
[20:24:36 CEST] <BtbN> Which is also very much not legal.
[20:24:51 CEST] <JEEB> I think you only need that for the 4K stuff that has a "secure path only" license
[20:25:04 CEST] <JEEB> the rest should not be that high security level? not that I know since I don't use netflix :)
[20:25:15 CEST] <BtbN> Anything higher than 720p is
[20:25:42 CEST] <JEEB> also this reminds me that some old old samsung TVs actually used widevine with libavformat :P
[20:25:51 CEST] <JEEB> there's still a source dump of theirs in a repo
[20:26:09 CEST] <JEEB> of course it has nothing to do with current widevine EME
[20:26:16 CEST] <JEEB> and mostly a fun factoid :)
[20:26:38 CEST] <JEEB> but at this point with EME I'd probably just have the EME thing decrypt it for me if I was looking into that stuff :P
[20:27:35 CEST] <durandal_1707> ways to break law are strictly prohibited here, last warning, next step is ban :)
[20:33:19 CEST] <esaym153> so I need to downmix a 5.1 movie to 2 channel. I know about the "-ac 2" flag. But that grabs the first audio stream (which is 5.1 but not english). I need to grab the second audio stream.
[20:33:33 CEST] <esaym153> I've tried all combos of stuff like "-ac:a:1" but that doesn't work
[20:33:47 CEST] <JEEB> stream selection by default is automagic and it picks stuff according to some rules
[20:33:59 CEST] <JEEB> see the mapping options (-map) in ffmpeg-all.html
[20:34:16 CEST] <JEEB> that lets you define which exact streams you want from your input (all automagic gets disabled)
[20:39:05 CEST] <esaym153> ok, I think -map 0:2  -ac 2 did it
[20:39:06 CEST] <esaym153> thanks
[20:41:37 CEST] <JEEB> np
[20:43:36 CEST] <JEEB> esaym153: also many 5.1 mixes when mixed down to stereo can be really low in volume. check -af "aformat=channel_layouts=stereo,loudnorm=I=-24,aresample=sample_rate=48000"
[20:43:45 CEST] <JEEB> instead of just -ac 2
[20:44:14 CEST] <esaym153> JEEB: yea, I've got a formula. I do this all the time, just never had the issue of two 5.1 streams in the same file
[20:44:24 CEST] <JEEB> alright
[20:45:54 CEST] <kepstin> esaym153: yeah, if you don't explicitly specify any -map options, then ffmpeg by default will pick one video stream + one audio stream from the file (whichever stream is marked as default, or the first one otherwise, i think)
[20:46:31 CEST] <JEEB> it has some "pick best" logic, so it does look at bit rates and channel counts etc
[21:36:22 CEST] <sine0> hey you GUYZ
[21:36:38 CEST] <sine0> the pls file contents still didnt work https://bpaste.net/show/VfKU
[21:40:35 CEST] <nine_milli> blb
[21:42:15 CEST] <durandal_1707> sine0: you are supposed to extract http links from it
[21:43:36 CEST] <durandal_1707> or as already mentioned download mpv, from https://mpv.io ....
[21:44:57 CEST] <furq> https://clbin.com/ryxAg
[21:44:58 CEST] <furq> works fine here
[21:55:53 CEST] <sine0> durandal_1707: yea there are 2 http links in it, I assume they are the streams
[21:56:22 CEST] <sine0> furq: do you think the quotes matter
[21:56:25 CEST] <sine0> around the rul
[21:56:26 CEST] <furq> i know the quotes matter
[21:56:31 CEST] <sine0> you knowz it mate
[00:00:00 CEST] --- Thu Jul 18 2019