[Ffmpeg-devel-irc] ffmpeg.log.20160907

Thu Sep 8 03:05:01 EEST 2016

[00:00:54 CEST] <haagch> jkqxz: well, that doesn't work: https://gist.github.com/ChristophHaag/a6b69563109a559b1e07d03a02e2ec9a
[00:01:11 CEST] <haagch> should probably make a bug report for that mesa change
[00:03:05 CEST] <jkqxz> I've looked at this further and I'm just writing a mail to mesa-dev.  The change to the behaviour of vaSyncSurface() is I think wrong in general.
[00:04:30 CEST] <haagch> cool, thanks
[00:19:10 CEST] <jkqxz> haagch:  https://lists.freedesktop.org/archives/mesa-dev/2016-September/128076.html
[05:57:47 CEST] <ricemuffinball> what is better? sonicare or oralb  eletronic tooth brush?
[12:01:31 CEST] <ricemuffinball> 5
[14:25:17 CEST] <archibald__> hi guys, im trying to understand why ffmpeg skips the first keyframe when i specify output -ss option to point precisely at a keyframe. Even when i do `ffmpeg -i in.mkv -ss 0 -c copy out.mkv` it skips the very first keyframe. It helps to specify timestamp just before that keyframe or, of course, enabling transcoding. Can anyone answer why it works like this?
[14:27:34 CEST] <friki> Hi. Is HDS demux still not supported for ffmpeg, right?
[14:50:05 CEST] <cuba_> hi
[14:50:30 CEST] <cuba_> how does ffmpeg handle a slight change in incoming FPS when encoding a video?
[14:50:49 CEST] <cuba_> or if it receives a few frames too much in contrast to the set fps rate when starting the process?
[14:52:00 CEST] <JEEB> ffmpeg in general doesn't handle frame rates, it handles timestamps
[14:52:03 CEST] <DHE> internally each frame has a presentation timestamp (pts) indicating the time it's meant to be shown.
[14:52:12 CEST] <JEEB> so if your input contains timestamps everything's OK
[14:55:16 CEST] <cuba_> at the moment I use image2pipe
[14:55:38 CEST] <cuba_> http://codepad.org/MbkNHghk
[14:55:59 CEST] <cuba_> ffmpeg will calculate the required pts on the read from the pipe I assume right?
[14:56:37 CEST] <DHE> what you want to do is set the framerate on the input, so that the timestamps are in a known state before hitting the encoder
[14:58:14 CEST] <cuba_> so -f image2pipe -framerate 10 instead of the -r 10 before the encoder?
[15:01:08 CEST] <DHE> items placed before the [-i inputsource] option affects the input in question. items placed before the [videooutputpath] affects the output
[15:01:35 CEST] <DHE> so you want to set the framerate first. ffmpeg will treat it like an MP4 with the requested framerate while reading your PNGs
[15:02:10 CEST] <cuba_> ok
[15:02:56 CEST] <cuba_> and when say my video input changes a bit in FPS, so i send 11 frames per second to the pipe it would lead to a slight error in the resulting video file right
[15:03:35 CEST] <cuba_> ffmpeg would add a non existing 0.1s to the h264 video
[15:04:08 CEST] <kepstin> cuba_: ffmpeg cli is designed primarily as a non-realtime (batch) tool. it doesn't matter how fast or slow you give it frames, if you use "-framerate 10" then it will treat the input frames as exactly 10fps.
[15:04:26 CEST] <cuba_> yes just wanted to confirm it
[15:04:37 CEST] <cuba_> Ive problems getting a good realtime encoding done
[15:06:00 CEST] <kepstin> if ffmpeg is encoding at slower than realtime or is blocked on something, it will actually block the application that's trying to feed it frames via pipe
[15:06:32 CEST] <kepstin> since it doesn't want to drop frames, and it assumes that the source isn't realtime.
[15:06:48 CEST] <cuba_> yes makes sense
[16:36:49 CEST] <meego> Hey, I'm looking with someone with good knowledge of static builds. Paid work, for a client of mine. We're trying to build highly optimized static builds for AWS Lambda. Anyone qualified & interested ?
[17:06:13 CEST] <DHE> meego: static builds are actually pretty easy if you just strip down the list of dependencies, like taking out x11grab and the like. disabling hwaccels, indevs and outdevs may be a good place to start
[17:08:03 CEST] <meego> DHE: yeah we've disabled-all and then white listed only the very few things we need
[17:08:38 CEST] <DHE> then adding --extra-ldflags=-static should be sufficient to get static builds (system libraries permitting)
[17:10:38 CEST] <meego> DHE: yeah, we did that too (see our configure flags https://gist.github.com/guillaumekh/8b1e9390448ae02b4dfaadfe7d17ad1a)
[17:12:44 CEST] <meego> DHE: ldd still gives the following libs are still dynamically linked : linux-vdso.so.1 libebur128.so.1 libm.so.6 libpthread.so.0 libc.so.6 libspeexdsp.so.1
[17:16:03 CEST] <meego> DHE: at this point we're ready to contract someone who can commit him/herself to help us out. Would you be interested ?
[17:16:27 CEST] <DHE> meego: no you didn't
[17:16:40 CEST] <DHE> line 7 becomes: --extra-ldflags="-L$HOME/ffmpeg_build/lib -static" \
[17:17:53 CEST] <meego> DHE: mmmmmc damn. Testing.
[17:18:32 CEST] <DHE> errors during testing may occur because the linker will want, for example, libXXX.a instead of libXXX.so
[17:26:05 CEST] <DHE> working out?
[17:45:03 CEST] <meego> DHE: problem solved. Thanks a lot!
[18:12:30 CEST] <DHE> meego: insert joke about getting money here. :)
[18:16:08 CEST] <meego> DHE: i was thinking it over, can you provide an invoice & bank account for transfer if i send a bit of money for the help ? :)
[18:18:31 CEST] <DHE> I'm good thanks
[18:27:35 CEST] <TwinTailed> What causes "Invalid data found when processing input" AVERROR to occur when doing avformat_write_header()????
[18:29:44 CEST] <meego> DHE: well ok, thx again for the helpful assistance!
[18:30:04 CEST] <TwinTailed> here is my code: http://pastebin.com/uXnHm52C
[18:36:29 CEST] <TwinTailed> Can anyone please help me?? The mailing list didn't answer this question...
[18:45:49 CEST] <DHE> TwinTailed: may be information logged. there are several possible reasons. perhaps you forgot to set the timestamps properly?
[18:46:06 CEST] <TwinTailed> DHE: how do i do that?
[18:46:23 CEST] <TwinTailed> The code is in pastebin i put the link above
[18:47:26 CEST] <DHE> when you run it, does it print anything to the error console?
[18:47:34 CEST] <TwinTailed> yes
[18:47:42 CEST] <DHE> I mean the av_log() interface
[18:47:42 CEST] <TwinTailed> i will give you the output, 1 sec
[18:48:19 CEST] <TwinTailed> DHE: http://pastebin.com/Bz1DcsC0
[18:48:58 CEST] <DHE> Tag avc1/0x31637661 incompatible with output codec id '28'   # this would be your main issue
[18:49:32 CEST] <TwinTailed> what does it mean
[18:49:33 CEST] <TwinTailed> ?
[18:50:50 CEST] <DHE> that the tag "avc1" isn't accepted to identify the H264 content, I guess... which is kinda odd...
[18:50:57 CEST] <DHE> but now outside my area of expertise
[18:53:14 CEST] <TwinTailed> DHE: what's a avc1 tag?
[18:54:56 CEST] <earthworm> What commands should I use to convert an entire .mp4 file to .webm without messing up the video/audio/codec? Is this a good command: ffmpeg -i input.mp4 -c:v libvpx -b:v 1M -c:a libvorbis output.webm
[19:01:47 CEST] <spreeuw> earthworm that would transcode it I think
[19:02:32 CEST] <spreeuw> earthworm: the most hip modern is vp9 with opus
[19:03:41 CEST] <spreeuw> http://wiki.webmproject.org/ffmpeg/vp9-encoding-guide
[19:03:59 CEST] <spreeuw> it wont play on slightly older android
[19:04:26 CEST] <spreeuw> and certain windows browsers
[19:05:35 CEST] <spreeuw> earthworm: what is inside the mp4?
[19:05:54 CEST] <spreeuw> if your words mean you just wnat to copy the streams into a webmcontainer
[19:06:01 CEST] <spreeuw> that is done differently I think
[19:06:44 CEST] <spreeuw> -vcodec copy -acodec copy
[19:07:06 CEST] <furq> that's probably not going to work
[19:19:01 CEST] <earthworm>  spreeuw: what do you mean whats inside the mp4? i downloaded it from youtube and now i want to convert it to webm format and have the same resolution as the mp4 without messing with the audio/video/codec or oversizing it
[19:20:15 CEST] <mvardan> Hi all, I am trying to use ffmpeg to encode video using HW accel (h264_qsv), I have compiled latest sources with enabled libmfx
[19:20:15 CEST] <mvardan> but when I'm trying to use I'm getting "Error initializing an internal MFX session"
[19:21:51 CEST] <spreeuw> Oh I misread your example , you were copying
[19:22:03 CEST] <spreeuw> just try it out
[19:58:45 CEST] <llogan> relaxed: would qemu work instead of actual hardware to provide ARM builds?
[19:59:10 CEST] <JEEB> you don't need an ARM thing to provide ARM builds
[19:59:17 CEST] <furq> yeah you can just cross compile
[19:59:24 CEST] <furq> qemu would be useful for testing that the builds actually work
[19:59:27 CEST] <JEEB> yes
[19:59:41 CEST] <JEEB> although they're not 100% like all the broken hardware, of course
[20:00:05 CEST] <llogan> i was "responding" to "People have expressed interest in ARM static builds, but I lack the hardware to make it happen. If someone donates the hardware I will provide regular static builds for that device."
[20:00:18 CEST] <furq> i was just looking at that about half an hour ago
[20:00:29 CEST] <JEEB> (´4@)
[20:01:29 CEST] <transhuman> hi http://paste.debian.net/813110/  <,--- error trying to compile mplayer... I was suggested to install ffmpeg to solve but it didnt...any ideas?
[20:01:44 CEST] <JEEB> sounds like mplayer support issue
[20:01:47 CEST] <JEEB> goto #mplayer
[20:02:23 CEST] <transhuman> sigh ok back there again...not sure if its either one
[20:02:34 CEST] <transhuman> thaks
[20:02:50 CEST] <JEEB> or you try mpv out and see if that builds more easily
[20:03:06 CEST] <llogan> doesn't mplayer include some sort of ffmpeg source?
[20:03:12 CEST] <furq> i'm guessing you're trying to build mplayer with cuvid support
[20:03:21 CEST] <furq> in which case you need libavcodec built with cuvid
[20:22:32 CEST] <TwinTailed> What causes "Tag avc1/0x31637661 incompatible with output codec id '28'"?
[20:23:25 CEST] <TwinTailed> Here is my code: http://pastebin.com/uXnHm52C
[20:23:56 CEST] <TwinTailed> Please help
[20:26:07 CEST] <llogan> you should probably ask libav-user mailing list
[20:26:29 CEST] <TwinTailed> llogan: tried, they didn't reply
[20:26:37 CEST] <TwinTailed> its been 3 days
[20:36:51 CEST] <relaxed> llogan: qemu is too slow, and I want to be able to test builds on the hardware.
[20:37:17 CEST] <llogan> i see. just curious.
[21:05:36 CEST] <transhuman> thanks furq llogan JEEB
[21:23:48 CEST] <DarrenPaul> Hello. Is any one free about a question on ffmpeg?
[21:25:23 CEST] <DarrenPaul> Maybe some one can help. Is there a protocol that is most stable to use at the source with ffmpeg, is udp or http more stable for uptime with ffmpeg. Thank you.
[21:31:51 CEST] <DHE> UDP is nice since it's connectionless. you can simply arrange to prevent ffmpeg from receiving errors from the receiver by blocking ICMP unreachables at either endpoint
[21:31:57 CEST] <DHE> or if it's multicast based, that doesn't even happen
[21:42:50 CEST] <DarrenPaul> @dhe was you talking to me?
[22:07:23 CEST] <DHE> i'm not an op... but yes I was talking to you
[22:09:08 CEST] <DarrenPaul> Ok thank you for the advice. Basicly i stream from the souce to middle ware then it usues http output. so the best for the input you think is UDP?
[23:02:14 CEST] <transhuman> furq how do i not build mplayer with cuvid support ...I dont need it...using these directions https://help.ubuntu.com/community/Compiling%20MPlayer
[23:03:00 CEST] <furq> no idea, i've never used mplayer
[23:03:19 CEST] <furq> you should probably use mpv these days
[23:05:04 CEST] <agrathwohl1> +1 for mpv
[23:09:25 CEST] <durandal_170> transhuman: mplayer development practically stoped
[23:22:42 CEST] <transhuman> so it seems
[23:22:56 CEST] <transhuman> I got it working on my other system. ...whats the alternative
[23:27:41 CEST] <DHE> <agrathwohl1> +1 for mpv    // and another +1 from me
[00:00:00 CEST] --- Thu Sep  8 2016