[Ffmpeg-devel-irc] ffmpeg.log.20181023

[burek]

[01:07:50 CEST] <dualz> Does anyone know where I can find a good write-up or tutorial on zmq and azmq?
[01:17:03 CEST] <KombuchaKip> Hey everyone. The ffmpeg pastebin subdomain isn't working for me, so I posted my question on migrating from an older libav API to ffmpeg 4 here: https://pastebin.com/Ezp8sNVE
[02:19:39 CEST] <Zexaron> Hello
[02:20:21 CEST] <Zexaron> some guys at linuc claim "ffmpeg uses libav" and pretty much act stupid when I wanted clarification if libav/ffmpeg can be used interchangibly, which I doubt
[02:21:07 CEST] <Zexaron> ffmpeg's release, DLLs, headers, API, exes probably aren't compatible to libav, I couldn't use a libav headers with ffmpeg's DLLs in a program right ?
[02:21:32 CEST] <Zexaron> Jut to confirm since Im clearing old code from a project which uses it interchangibly, but clearly using only ffmpeg
[02:23:24 CEST] <Zexaron> Or the idiot is confusing the libav project with libav source code names
[02:23:42 CEST] <furq> it's almost certainly the last thing you said
[02:24:32 CEST] <furq> and yeah the APIs have diverged a lot
[02:25:19 CEST] <furq> you might be able to swap the libs for some very simple program
[02:25:24 CEST] <furq> but generally no
[02:26:00 CEST] <Zexaron> Indeed, the split happened quite some time ago, like pre 2010 if im not mistaken ?
[02:26:06 CEST] <furq> 2011
[02:26:20 CEST] <Zexaron> ah close
[02:28:08 CEST] <Zexaron> Another thing ...
[02:28:24 CEST] <Zexaron> went asking in #cmake but nobody was around
[02:28:32 CEST] <Zexaron> c/p -ed
[02:29:01 CEST] <Zexaron>  1. so the Win64 platform switched over to shared DLLs and has it's own code to check if FFmpeg DLLs are present
[02:29:16 CEST] <Zexaron>  2. but I came across some cmake code that sets "HAVE_FFMPEG" bit but i'm not sure what to do, I want to split away Win32/64 away from this linux/osx stuff
[02:29:30 CEST] <Zexaron>  3. Here's one of the CmakeLists files https://pastebin.com/X9atYeMZ
[02:29:51 CEST] <Zexaron>  4. for win32 entry the path was renamed from "Externals/ffmpeg" to Externals/ffmpeg-win64, since it does not contain any custom prebuilt .lib files anymore, those .lib just point to delay loaded DLLs
[02:30:12 CEST] <Zexaron>  5. Would that Win32 entry still be relevant, it does have to point to libs which then point to DLLs for cmake too?
[02:31:13 CEST] <Zexaron>  - end - i might not have to do much other than to rename HAVE_FFMPEG into HAVE_FFMPEG_NONWIN32 is my currenty observation
[09:19:09 CEST] <KombuchaKip> Hey everyone. The ffmpeg pastebin subdomain isn't working for me, so I posted my question on migrating from an older libav API to ffmpeg 4 here: https://pastebin.com/Ezp8sNVE
[10:13:40 CEST] <darsain> I'm trying to convert 320kbps mp3 to vbr 1 using ffmpeg, but comparing the same encode with foobar2000 ffmpeg takes more than twice the time (8-10 seconds vs 4 seconds) than foobar2000 to do that
[10:13:46 CEST] <darsain> is there some flag I'm not enabling? here are my arguments:
[10:13:52 CEST] <darsain> -i file.mp3 -q:a 1 -c:v copy -id3v2_version 3 -f mp3 -y file2.mp3
[12:37:35 CEST] <SortaCore> fellas
[12:37:42 CEST] <SortaCore> how do I escape a double-quote in metadata
[12:37:53 CEST] <SortaCore> -metadata title="\"thing\"" no work
[12:39:13 CEST] <SortaCore> *blows raspberry* no it was missing parts in output filepath
[12:39:29 CEST] <SortaCore> missing folder, even tho I told it to create the directory first
[12:39:53 CEST] <SortaCore> you may resume normal programming
[13:28:22 CEST] <relaxed> darsain: maybe libmp3lame wasn't compiled with nasm
[13:29:38 CEST] <darsain> relaxed: I'm using the all in one ffmpeg.exe windows binary. is this a known issue with it?
[13:38:54 CEST] <pdm91> video metadata is not copied to the output file. Here is my command "ffmpeg -i in.mp4 -b:v 4000k -minrate 3000k -maxrate 6000k -s 1920x1080 -r 30 -vcodec h264 -acodec aac -map_metadata 0 -metadata:s:v:0 -strict -2 -y out.mp4"
[15:06:48 CEST] <zivanovicb> Error: Command failed: ffprobe -v 0 -of csv=p=0 -select_streams 0 -show_entries stream=r_frame_rate, width, height /files/efab270e2f13754e0d4f9458f279799b
[15:07:06 CEST] <zivanovicb> Any ideas what could be wrong with this command?
[16:11:46 CEST] <dualz> My issue has come up a few times that I can find on google with no good answer
[16:12:11 CEST] <dualz> I want to be able to change my inputs on the fly
[16:12:25 CEST] <dualz> for a live streaming app I'm working on
[16:13:16 CEST] <dualz> What I'm thinking of doing is using libzmq and setting up all my inputs in a movie/amovie filter
[16:18:53 CEST] <dualz> then use zmqsend to movie at input_a filename rtmp://new/stream/here
[16:19:20 CEST] <dualz> then somehow I'd have to reinit
[16:24:17 CEST] <furq> dualz: use the streamselect filter
[16:24:46 CEST] <JEEB> lavfi in general is really static though, so it won't handle the dynamic switching though if you go and come back
[16:24:57 CEST] <JEEB> I've been wondering of using upipe for that
[16:25:11 CEST] <JEEB> (since most of my inputs are broadcast anyways)
[16:25:31 CEST] <dualz> hmm
[16:25:43 CEST] <dualz> let me check out streamselect
[16:25:53 CEST] <furq> yeah if you need to continue through dropouts then ffmpeg alone is no use to you
[16:26:35 CEST] <dualz> dropouts I can listen to on my end
[16:26:50 CEST] <dualz> and send a msg via libzmq
[16:27:11 CEST] <dualz> was the intentions
[17:58:42 CEST] <Dudemanguy> Hi, I have some questions about the metadata API and example on the website here: https://libav.org/documentation/doxygen/master/metadata_8c-example.html
[17:59:03 CEST] <Dudemanguy> More specifically, I would like to be able to extract metadata from audio files
[17:59:26 CEST] <Dudemanguy> From the code there, I would expect the printed output to be all of the metadata contained in file, but this isn't the case
[17:59:46 CEST] <Dudemanguy> I'm only able to return the encoder tag for some reason
[18:00:00 CEST] <durandal_1707> Dudemanguy: libav.org != ffmpeg.org
[18:00:22 CEST] <Dudemanguy> ah wrong channel then?
[18:00:45 CEST] <Dudemanguy> apologies
[18:07:20 CEST] <Dudemanguy> Oops, I got my libav and ffmpeg links mixed up earlier; but the same example is up on ffmpeg actually: https://www.ffmpeg.org/doxygen/2.7/metadata_8c-example.html
[18:08:02 CEST] <Dudemanguy> Anyways just to repeat if neccesary: when I run this code, I'm only able to get the encoder tag from an audio and not any other metadata
[18:08:23 CEST] <Dudemanguy> I'm probably just missing something here, but any help on this appreciated
[18:09:30 CEST] <durandal_1707> Dudemanguy: and what other metadata you want?
[18:09:48 CEST] <Dudemanguy> Anything: ARTIST, ALBUM, etc.
[18:10:16 CEST] <durandal_1707> Dudemanguy: does ffprobe show such metadata for same input file?
[18:10:32 CEST] <Dudemanguy> yes which is why I'm confused
[18:10:55 CEST] <furq> wouldn't stream metadata be in the AVStream
[18:14:19 CEST] <Dudemanguy> ah that could be it
[18:20:41 CEST] <Dudemanguy> furq: perfect, that did the trick
[18:21:05 CEST] <Dudemanguy> just changed fmt_ctx->metadata to fmt_ctx->streams[0]->metadata and I got what I expected
[18:21:12 CEST] <Dudemanguy> thanks a ton
[19:01:41 CEST] <raytiley> is it possible for ffmpeg to receive an rtmp stream standalone... Like say I an encoder that can send a stream to an rtmp url, can ffmpeg be the receiver?
[19:01:48 CEST] <raytiley> or do I need something like nginix-rtmp
[19:02:05 CEST] <JEEB> pretty sure the lavf rtmp support is for reading from a server or pushing to a server
[19:02:11 CEST] <JEEB> not being a server itself
[19:06:19 CEST] <raytiley> kinda what I figured...
[19:09:23 CEST] <raytiley> basically I have an RTP  / MPEG-TS receiver implementation that is naive and doesn't drop audio if packets are lost... I'm trying to bandaid it by having ffmpeg capture the incoming stream and align it before restreaming it via rtp. Was going to try ingesting rtmp since it's TCP... but since that is not possible, is there a command that will do what I want?
[19:10:02 CEST] <furq> iirc you can listen for rtsp but not rtmp
[19:10:28 CEST] <furq> if you're just sending it off to another server then that might work
[19:11:09 CEST] <raytiley> ffmpeg -i rtp://127.0.0.1:1234 -c:v copy -c:a copy -f mpegts rtp://127.0.0.1:3456
[19:11:13 CEST] <furq> actually i guess rtmp has -listen 1 now so maybe that works
[19:11:39 CEST] <furq> neither of them are actually usable as servers but it might work for just restreaming
[19:12:13 CEST] <raytiley> furq:  thanks, I'll look closer at that option
[20:11:16 CEST] <KombuchaKip> furq: The ffmpeg pastebin subdomain isn't working for me, so I posted my question on migrating from an older libav API to ffmpeg 4 here: https://pastebin.com/Ezp8sNVE
[20:12:54 CEST] <JEEB> KombuchaKip: personally I just used the libavfilter audio resampling. that way you can just feed the AVFrames from the decoder to it
[20:13:11 CEST] <JEEB> although I think swresample should now have an AVFrame based API as well
[20:13:53 CEST] <durandal_1707> yes it have avframe api, but perhaps they do not use AVFrames at all
[20:14:14 CEST] <JEEB> well the top comment says they decode audio from "any format" which does hint at lavf+lavc
[20:14:18 CEST] <JEEB> which would have AVFrames
[20:33:03 CEST] <KombuchaKip> JEEB: What would you recommend?
[20:40:41 CEST] <JEEB> KombuchaKip: depending on various factors if you're using libavcodec for decoding (And thus receive AVFrames of audio), I'd use the AVFrame API for swresample, or just the avfilter stuff which wraps it
[20:41:11 CEST] <KombuchaKip> I am using libav's decoder which I believe is libavcodec.
[20:41:26 CEST] <JEEB> yup
[20:41:37 CEST] <JEEB> so https://www.ffmpeg.org/doxygen/trunk/group__lavc__encdec.html (or the older version)
[20:41:44 CEST] <JEEB> which returns AVFrames
[20:41:58 CEST] <JEEB> so it would make sense for you to use AVFrame-based APIs
[20:42:56 CEST] <KombuchaKip> JEEB: Which I believe is what I'm doing already?
[00:00:00 CEST] --- Wed Oct 24 2018