[Ffmpeg-devel-irc] ffmpeg.log.20180408

[burek]

[03:45:20 CEST] <FishPencil> Is there a command to see all the pixel formats supported for a given encoder?
[03:51:07 CEST] <furq> FishPencil: -h encoder=name
[05:53:22 CEST] <mvmv> Hi. Is is possible to use image2pipe to take a series of images and output them to an rtmp stream?
[06:48:01 CEST] <mvmv> I was disconnected briefly after asking my question, so I am reasking it. Apologies for the repetition or if there was a response while I was disconnected. --- Is ffmpeg capable of using image2pipe to take a series of images and output them to an rtmp stream? I'd like to understand whether this functionality is even supported prior to troubleshooting further or to asking more detailed questions.
[06:56:36 CEST] <furq> mvmv: it should work the same as anything else
[07:05:54 CEST] <mvmv> furq: Good, thank you, that helps to know.
[08:09:01 CEST] <Vasu> Hi! Is this channel active?
[08:11:20 CEST] <nfobot> Vasu: Available functions: muxer demuxer encoder decoder filter source sink indev outdev protocol bsf
[08:14:02 CEST] <Vasu> Guess this channel isn't very active :(
[08:19:50 CEST] <Vasu> hi sibyakin
[09:00:37 CEST] <Vasu> is anyone here?
[09:00:50 CEST] <Vasu> I have a question about using ffmpeg with named pipes
[09:24:10 CEST] <Vasu> is anyone here?
[09:24:21 CEST] <Vasu> I wonder if I'm muted
[10:15:12 CEST] <Hades_> hi there!
[10:15:25 CEST] <Hades_> doesn't look like you're muted
[14:33:52 CEST] <killown> is there some optimized way to add logos in videos that is faster to process?
[14:39:52 CEST] <furq> faster than what
[15:59:19 CEST] <Li> what ffmpeg command on linux to turn /dev/video0 to form possible to embed within html src of a video tag?
[16:00:20 CEST] <Li> viewer of the page will over ethernet will be looking through a video camera connected to another machine served over http
[17:24:18 CEST] <frankyboy_> hello :) struggeling while trying to capure audio stream with ffmpeg from sound card. tried all cards from arecord -L output, but sound didn't caputred. what is correct command to capture audio with ffmpeg
[17:26:14 CEST] <c_14> sound from a microphone or sound playing from a different sound source on your pc?
[17:27:30 CEST] <frankyboy_> c_14, no, not microphone, i am trying to record screen, and also need for sound in video of a game
[17:28:16 CEST] <c_14> https://trac.ffmpeg.org/wiki/Capture/ALSA#Recordaudiofromanapplication
[17:28:40 CEST] <c_14> or are you using pulse?
[17:29:33 CEST] <frankyboy_> c_14, nope, with pulse there wasn't any problem to record. thanks i'll give a try snd_aloop :D
[17:31:04 CEST] <debianuser> frankyboy_: Maybe your card supports hardware what-you-hear? Can you show more details about your card? You can use alsa-info script: https://wiki.ubuntu.com/Audio/AlsaInfo it should automatically suggest you to upload your data and give you a link to it (you can run it as a regular user, it doesn't need root).
[17:35:51 CEST] <frankyboy_> debianuser, http://ix.io/17ja
[17:51:51 CEST] <frankyboy_> https://stackoverflow.com/questions/48405541/recording-system-audio-with-alsa that helped to start capturing audio :D
[17:58:00 CEST] <debianuser> frankyboy_: Yes, that'd work, however I'd suggested you a dmix-based config like this: http://pastebin.com/B7iEKBwH (replace "RealCardName" in lines 5 and 25 with "PCH" - that's the name of your card) Without dmix only one app can play to the soundcard at a time.
[17:59:37 CEST] <debianuser> Ah, add one more line to that config:
[17:59:40 CEST] <debianuser>   pcm.nowplaying "plug:\"dsnoop:Loopback,1\""
[17:59:44 CEST] <debianuser> That's a shortcut. Then you can capture with `ffmpeg -f alsa -i nowplaying ...`
[18:00:10 CEST] <debianuser> As for the hardware-based what-you-hear feature...
[18:01:05 CEST] <debianuser> frankyboy_: In your codec the audio output (node 0x02) goes to mixer node 0x26 that has no routes back to audio-in nodes. So, no standard way to route output back to input... But there's a "non-standard" one: you can route speakers (node 0x14) back to audio input through the 0x23 mixer. If you want to try that:
[18:01:07 CEST] <debianuser>   sudo hda-verb /dev/snd/hwC0D0 0x14 SET_PIN_WIDGET_CONTROL 0x60 # set 0x14 as OUT+IN
[18:01:09 CEST] <debianuser>   sudo hda-verb /dev/snd/hwC0D0 0x23 SET_AMP_GAIN_MUTE 0x5400 # unmute route from 0x14 left
[18:01:11 CEST] <debianuser>   sudo hda-verb /dev/snd/hwC0D0 0x23 SET_AMP_GAIN_MUTE 0x6400 # unmute route from 0x14 right
[18:01:16 CEST] <debianuser> Those are direct codec configuration commands. They'd work right away and should let you capture both your mic (if you have a mic plugged in) and your speakers from a regular alsa input. Also that's a runtime change, it won't persist on reboot. (i.e. if anything goes wrong you can always reboot to get back to normal)
[18:02:01 CEST] <frankyboy_> debianuser, thanks, your cfg working like a charm
[18:02:04 CEST] <debianuser> Pick whichever you like. :) And feel free to ask any questions!
[18:32:17 CEST] <kevinnnn> Hi all, as a general rule I know I am not supposed to ask if I am allowed to ask a question. But is it okay to ask a question slightly unrelated to ffmpeg here?
[18:35:14 CEST] <atomnuker> yeah
[18:38:30 CEST] <kevinnnn> atomnuker: thank you so much! I've been on the xorg-devel chat and I haven't gotten anyone to reply... Anyways I have an xlib application I wrote and it is freezing (not crashing, freezing). It is basically a while true loop that is calling XShmGetImage over and over again. I got the stacktrace of my program here as well and i can't for the life of me decipher what is going on: https://pastebin.com/bNE4fzmf
[18:38:58 CEST] <kevinnnn> If you could take a look that would be so great!
[18:42:51 CEST] <debianuser> kevinnnn: Looks like it's just waiting for events from X11 socket and not receiving any. x11trace would be more useful here - you'd see what was the last request it asked for.
[18:43:31 CEST] <debianuser> (to keep things on topic) kevinnnn: you can also compare that to x11trace of ffmpeg or ssr capturing the screen to see what's the difference. :)
[18:44:08 CEST] <kevinnnn> debianuser: okay let me try x11trace real quick and I'll let you know what I find! Thank you for always being so helpful :)
[18:45:18 CEST] <kevinnnn> debianuser: you mean xtrace?
[18:50:48 CEST] <debianuser> kevinnnn: Yes, xtrace (it's `x11trace` in some distros, and `xtrace` in others)
[18:52:16 CEST] <debianuser> ( https://www.x.org/wiki/guide/debugging/ also suggests `xscope`, `xmon` and `x11vis` but I've never used those )
[19:06:30 CEST] <kevinnnn> debianuser: https://pastebin.com/vYdgT3vR
[19:06:45 CEST] <kevinnnn> There is the last 100 lines of output from xtrace
[19:06:51 CEST] <kevinnnn> before it crashes
[19:07:03 CEST] <kevinnnn> or freezes, sorry not crashes
[19:13:26 CEST] <debianuser> kevinnnn: I see no obvious reasons to freeze. Does the output of xtrace stop too? Or do you still see events in the xtrace log when you move your mouse over your app window?
[19:32:10 CEST] <kevinnnn> debianuser: Yes the output stops too
[19:50:22 CEST] <kevinnnn> debianuser: I suspected that the window manager had something to do with the problem so I added it to the xtrace as well
[19:50:33 CEST] <kevinnnn> debianuser: here is the output from that: https://pastebin.com/4k3BWgeh
[19:50:39 CEST] <kevinnnn> It is once again freezing there
[19:52:23 CEST] <kevinnnn> debianuser: it might be worth noting that XShmGetImage is where my program freezes
[19:52:31 CEST] <kevinnnn> thanks again for the help
[20:09:47 CEST] <Li> what ffmpeg command on linux to turn /dev/video0 to form possible to embed within html src of a video tag?
[20:09:54 CEST] <Li> viewer of the page will over ethernet will be looking through a video camera connected to another machine served over http
[20:12:10 CEST] <debianuser> Li: /dev/video0 is a streaming, and <video> tag can only handle files, it can't handle streaming on its own, can it?
[20:14:05 CEST] <furq> you probably want hls or something
[20:15:40 CEST] <debianuser> yeah, it's just I mean you can't embed hls into a <video>, you need some javascript helper, or adobe flesh helper, or some server-side helper (e.g. ffserver), you can't watch streaming with bare <video>, can you?
[20:15:58 CEST] <debianuser> *adobe flash helper
[20:18:26 CEST] <furq> adobe flesh
[20:18:47 CEST] <furq> and yeah you need hls.js or something
[20:18:59 CEST] <furq> that's the least painful method of doing it though
[20:20:26 CEST] <Mavrik> well, <video> will work fine for Safari and mobile browsers, it just won't work on most desktop browsers without JS helpers :)
[20:26:06 CEST] <debianuser> furq, Li: https://gist.github.com/riledhel/4e76868c496e11e773094b70fa566e0b ?
[20:29:10 CEST] <furq> something along those lines, yeah
[20:59:24 CEST] <TikityTik> I'm losing a lot of audio quality when encoding from aiff to libvorbis with -q:a 10
[20:59:27 CEST] <TikityTik> why is this?
[21:00:24 CEST] <TikityTik> original is pcm_s16be
[21:03:01 CEST] <TikityTik> and there is a big pop
[21:03:12 CEST] <iive> does ffplay replay the aiff correctly?
[21:03:58 CEST] <TikityTik> yes
[21:06:07 CEST] <TikityTik> I'm using a windows updated build with the command: .\ffmpeg.exe -i .\snap.aiff -c:v libopus -q:a 10 -speed 0 -threads 8 -y snap.ogg
[21:06:08 CEST] Action: debianuser tested the html sample from that gist and it works! Maybe someone can add it to https://trac.ffmpeg.org/wiki/StreamingGuide or https://trac.ffmpeg.org/wiki/Capture/Webcam ?
[21:07:10 CEST] <TikityTik> and i am trying to conver this: https://freesound.org/people/SoundCollectah/sounds/109399/
[21:07:24 CEST] <furq> TikityTik: that's opus, not vorbis
[21:07:30 CEST] <furq> use -b with opus
[21:07:45 CEST] <TikityTik> i'm sorry, i tested first with libvorbis then libopus
[21:07:48 CEST] <TikityTik> same problem in both
[21:08:00 CEST] <TikityTik> the audio is vastly different
[21:09:53 CEST] <TikityTik> actually i trimmed it down to 0.64 seconds and it does that problem, but not with the original file
[21:11:16 CEST] <TikityTik> yeah when i do -t 0.64, it adds a big *pop* sound at the start
[21:13:23 CEST] <TikityTik> ah....i'm sorry actually this is problem with VLC
[21:40:40 CEST] <tmatth> TikityTik: do you want to open a ticket at trac.videolan.org?
[21:41:04 CEST] <TikityTik> it's problem a setting problem anyhow
[00:00:00 CEST] --- Mon Apr  9 2018