[Ffmpeg-devel-irc] ffmpeg.log.20161109

[burek]

[00:08:05 CET] <Min> okey I got it working, thanks for helping guys
[00:17:54 CET] <Phi> hm
[00:18:01 CET] <Phi> it doesn't seem to use libmfx properly
[00:18:23 CET] <Phi> it's expecting headers in "mfx/xxx", but the newest libmfx files are just in "include/xxx"
[00:22:16 CET] <llogan> furq: not sure why he didn't say what he did to "get it working". probably remuxing as you suggested.
[00:28:31 CET] <furq> i vaguely remember there being some longstanding bug report about this
[00:35:37 CET] <furq> huh
[00:35:52 CET] <furq> this only happens with libx264
[00:36:23 CET] <furq> in any container, with any audio codec
[00:38:31 CET] <furq> http://vpaste.net/aBg8H
[07:24:07 CET] <kepstin> furq: I assume it has to do with x264's encoder delay, you can stuff hundreds of frames into it before getting stuff out depending on settings, threads, etc.
[07:25:13 CET] <kepstin> so if you're calculating shortest based on the x264 encoder's output, and stop giving it input when you hit the desired length, you still have a good chunk of frames to flush out of the encoder, i guess?
[08:53:30 CET] <Chloe> does ffmpeg have anything to attempt to fix PNGs?
[08:53:40 CET] <Chloe> from the CRC32
[08:54:26 CET] <Chloe> or a way I can extract the raw data of a chunk and the CRC
[08:55:57 CET] <kerio> how do you fix a png from a crc32
[09:07:11 CET] <Chloe> change bits until the crc32 is correct
[09:08:45 CET] <kerio> lmao
[09:09:01 CET] <kerio> how big is a chunk?
[09:09:52 CET] <kerio> like
[09:09:56 CET] <kerio> how much data is checksummed?
[09:18:23 CET] <Chloe> large
[09:19:01 CET] <Chloe> but it's ok, I'll try it anyway >.< I just need to be able to extract the chunk data mainly
[11:56:21 CET] <deadbeefy> Hi, I'm having trouble when recording the screen, only a few frames are captured and then it starts dropping all frames. The number of frames captured seem to be constant when not changing parameters but vary depending on the capture resolution. I'm on ubuntu/xenial and using ffmpeg 3.2.1 from ppa jonathonf/ffmpeg-3.
[11:56:40 CET] <deadbeefy> here's the command I'm using: ffmpeg -video_size 64x64 -framerate 25 -f x11grab -i $DISPLAY -y output.mp4
[12:42:59 CET] <n4zarh> hello there, I might have a question about ffmpeg in c/c++ and memory-based crashes
[12:46:03 CET] <n4zarh> I use C functions of ffmpeg in a native library for my android app. I use threads for every single encoder/decoder (for example one thread per audio and video decode). Each thread inits decoder once, proceeds with decoding, and after being interrupted it uninits decoder.
[12:47:11 CET] <n4zarh> While it worked perfectly on sample application, on main app (where I want to use that library) uniniting decoders tends to crash whole app
[12:49:08 CET] <n4zarh> it happens on closing/freeing codec, freeing frames and sometimes on single non-ffmpeg function which clears some memory as well. I doubt it's ffmpeg fault (because of last instance), but I want to make sure: is it possible that it's ffmpeg fault at those crashes?
[12:50:48 CET] <bencoh> don't you have a demux (avformat) as well?
[12:51:30 CET] <n4zarh> nope
[12:51:32 CET] <bencoh> where does it live, and how do you init/close it?
[12:51:32 CET] <bencoh> ah
[12:52:17 CET] <n4zarh> only on closing
[12:52:25 CET] <bencoh> ?
[12:52:52 CET] <n4zarh> avcodec_close(c) or av_free(c) (where c == codec context)
[12:53:21 CET] <n4zarh> the thing is, it happens quite randomly, that's why I doubt it is ffmpeg fault, but I need to make sure
[12:54:16 CET] <bencoh> well you could try running a unit-test of your native library through valgrind
[12:54:41 CET] <bencoh> (with just a few samples / small frames as an input)
[12:59:20 CET] <nonex86> using ffmpeg in my multithreaded application without any problem
[12:59:43 CET] <nonex86> btw its 24/7 software
[12:59:43 CET] <bencoh> me too (at least did so in the past) so ...
[13:01:58 CET] <ritsuka> bencoh: check av_lockmgr_register()
[13:02:03 CET] <relaxed> deadbeefy: try using -framerate 60 for the input and lower the framerate for the output with -r
[13:02:18 CET] <nonex86> n4zarh: and, btw, your scaler code you post before contains a bug, thats why you did not get your frame properly
[13:02:43 CET] <ritsuka> opps I meant n4zarh
[13:04:15 CET] <nonex86> n4zarh: agree with ritsuka, you can provide to ffmpeg lock manager or just use critical sections/mutex/futex yourself to guard some ffmpeg calls
[13:04:31 CET] <nonex86> n4zarh: usually thats stated clearly in documentation/header files
[13:04:48 CET] <n4zarh> I see
[13:43:19 CET] <deadbeefy> relaxed: 60 fps didn't help, but 80 fps seems to do the trick
[13:43:33 CET] <deadbeefy> relaxed: any idea as to why this is necessary?
[13:51:09 CET] <deadbeefy> hmm, actually it doesn't work :(
[13:53:23 CET] <ciawal> I still have a problem with ffmpeg not seeing the first frame in a video I'm working with
[13:53:23 CET] <ciawal> when I dump all the frames its not there, and when I perform a filter into another video file its not included
[13:53:23 CET] <ciawal> can anyone suggest anything?
[13:54:57 CET] <jkqxz> "-vsync 0"
[13:56:17 CET] <jkqxz> (If the frame is actually in the file and gets decoded, then the only way you should normally be able to lose it after that is by timestamp issues.  That should turn off ffmpeg doing anything funny there.)
[14:07:38 CET] <deadbeefy> to clarify my problem, this captures 5 frames, then it just drops every frame: ffmpeg -f x11grab -i $DISPLAY output.nut
[14:08:07 CET] <deadbeefy> while the same ffplay command works fine: ffplay -f x11grab -i $DISPLAY
[14:13:15 CET] <jkqxz> deadbeefy:  Is your setup the same as <http://ffmpeg.org/pipermail/ffmpeg-user/2016-November/034260.html>?
[14:32:03 CET] <deadbeefy> jkqxz: yes!
[14:36:00 CET] <relaxed> deadbeefy: you can try my static build, https://www.johnvansickle.com/ffmpeg/
[14:36:01 CET] <jkqxz> See <http://ffmpeg.org/pipermail/ffmpeg-user/2016-November/034286.html> and reply for some investigation.
[14:36:04 CET] <jkqxz> Does it work if you build your own ffmpeg without the 9001 configure options?
[14:37:46 CET] <deadbeefy> relaxed: sure, one moment!
[14:38:59 CET] <deadbeefy> works like a charm
[14:42:45 CET] <ciawal> jkqxz: I'm running this: ffmpeg -vsync 0 -i input.mp4 -f image2 thumb%02d.jpg
[14:42:45 CET] <ciawal> but the frame is still missing :(
[14:44:37 CET] <ciawal> I believe the first frame is identical to the last one, I wondered if there might be some special feature being used which references it
[14:44:37 CET] <ciawal> it doesnt show in vlc either
[14:45:14 CET] <relaxed> vlc uses ffmpeg's libs
[14:47:18 CET] <jkqxz> You could remux the video stream to something else without moving the metadata and see if the frame is there or not.
[14:47:27 CET] <deadbeefy> relaxed: thanks for the help, much obliged!
[14:49:09 CET] <relaxed> deadbeefy: You're welcome. You should file a bug report on debian's ffmpeg (or add to an existing bug report)
[14:53:00 CET] <relaxed> ciawal: have you tried remuxing the input into mkv first?
[14:54:20 CET] <ciawal> I'd tried avi previously, just tried mkv but same result
[14:54:39 CET] <ciawal> the frame number is wrong if I use ffprobe also
[14:54:44 CET] <ciawal> 68 when 69 is expected
[15:21:44 CET] <brontosaurusrex> an easy cli way to get duration of video file in hh:mm:ss:ff (ff=frames)?
[15:31:42 CET] <brontosaurusrex> or should i make some math like frames=round(miliseconds/fps)?
[15:33:52 CET] <nonex86> fps can be variable...
[15:37:57 CET] <brontosaurusrex> hm, yeah, whats the math in that case?
[15:38:35 CET] <brontosaurusrex> i guess none, doesnt make sense
[16:06:26 CET] <termos> Is there an easy way to get access to a parent this pointer in the function I set as av_log_set_callback? I have problems using std::bind because of the va_list argument
[16:06:59 CET] <termos> std::bind(&Class::NonStaticMember, this) was my attempt
[16:57:01 CET] <brontosaurusrex> another q: if i assume 25 fps, what is that called? 25fps base?
[17:39:21 CET] <brontosaurusrex> got some bash working https://raw.githubusercontent.com/brontosaurusrex/singularity/master/bin/durtc
[17:39:39 CET] <brontosaurusrex> not very fast, but does the trick.
[18:34:49 CET] <Croepha> Hi, trying to get to use ffmpeg api to play video and I seem to get the first frame of the video, but each frame after seems to be the same thing as the first video frame... any newb mistake I might be making?
[18:52:10 CET] <Croepha> this is my code btw: http://dpaste.com/25050T2
[19:50:45 CET] <kaipee> hey gus, I'm getting an error : "Could not write header for output file #0 (incorrect codec parameters ?): Invalid data found when processing input"
[19:51:08 CET] <kaipee> prior to that is : "[matroska @ 0x80a84a000] Invalid chapter start (6154481000000) or end (6131965000000)."
[19:51:32 CET] <kaipee> does anybody have an idea as to what the problem is?
[19:51:45 CET] <kaipee> (more importantly, how to resolve it?)
[19:53:32 CET] <furq> pastebin the full command and output
[19:53:46 CET] <furq> based on that it looks like you have a chapter which ends before it starts
[19:55:11 CET] <kaipee> ah OK
[19:55:19 CET] <kaipee> any way to edit (or ignore) that?
[19:57:52 CET] <Phi> on a unrelated note, anyone know how to get Intel QSV working on a Windoze environment?
[19:58:59 CET] <Phi> the example uses libav, but is that even for Windows?
[20:03:44 CET] <kaipee> furq: how do I output to a log file? (BSD commandline)
[20:05:35 CET] <kaipee> furq: pastebin > http://pastebin.com/kCqymjQm
[20:06:20 CET] <furq> Chapter #0:19: start 6154.481000, end 6131.965000
[20:06:24 CET] <furq> yeah that's no good
[20:06:31 CET] <furq> you can disable chapters with -map_chapters -1
[20:07:00 CET] <furq> if you want to keep them you'll have to fix them in the source with mkvtoolnix or something
[20:07:55 CET] <DHE> start is after the end...
[20:08:16 CET] <furq> the chapter before that has the same end time,
[20:08:25 CET] <furq> so i'm guessing those times are just swapped for whatever reason
[20:32:05 CET] <Phi> any idea for my scenario folks?
[20:36:16 CET] <Phi> Intel QSV on Windows
[20:36:37 CET] <Phi> the QSV example uses libva, which looks like a Linux-style only
[20:38:26 CET] <furq> don't you need libmfx on windows
[20:43:18 CET] <kaipee> ok cool, thanks furq
[20:43:45 CET] <kaipee> would disabling chapters prevent skipping? or what side-effect would it have ?
[20:48:19 CET] <furq> it would prevent seeking to chapter markers
[20:48:27 CET] <furq> it won't prevent seeking in general
[20:48:39 CET] <Phi> I have libmfx linked up
[20:48:59 CET] <Phi> in the configure I've got --enable-libmfx, and the enable-encoder/decoder/etc for h264_qsv
[20:49:09 CET] <Phi> that all turned out find, I got it all linked
[20:49:26 CET] <Phi> ... as in, configured, maked, linked to my VS project
[20:49:39 CET] <shincodex> tell me why -Wl,-rpath,./ does not load the stupid shared library from ,.
[20:49:40 CET] <shincodex> ./
[20:49:51 CET] <shincodex> and ldd says library is being looked for in ../
[20:50:24 CET] <furq> kaipee: you probably just want to edit the chapters in mkvtoolnix
[20:50:59 CET] <kaipee> ok ta
[20:51:01 CET] <furq> either with the gui or with mkvpropedit
[20:51:09 CET] <BtbN> you don't ever want to have . in your rpath
[20:51:13 CET] <BtbN> that's as bad as security can get.
[20:51:15 CET] <furq> probably the former because the latter looks like it requires hand-editing xml
[20:51:20 CET] <BtbN> most loaders block it now
[20:51:29 CET] <kaipee> great, thanks
[20:56:11 CET] <gentwo> ffprobe ffprobe -v error -select_streams v:0 -show_entries stream=avg_frame_rate -of default=nw=1:nk=1 -show_entries name=filename SampleVideo_720x480_1mb.mp4
[20:56:35 CET] <gentwo> ^ how do i get just the filename with show_intries ?
[20:59:37 CET] <furq> -show_entries format=filename
[21:00:33 CET] <shincodex> yeah
[21:00:36 CET] <shincodex> well
[21:00:47 CET] <gentwo> ffprobe -v error -select_streams v:0 -show_entries stream=avg_frame_rate,format=filename, -of default=nw=1:nk=1 SampleVideo_720x480_1mb.mp4
[21:00:50 CET] <shincodex> ./sofolder/
[21:01:08 CET] <gentwo> furq: still no filename outputs
[21:01:29 CET] <furq> replace the first , with :
[21:01:33 CET] <furq> and get rid of the second one
[21:01:52 CET] <furq> it seems like you already have the filename though
[21:02:40 CET] <gentwo> furq: thanks, that does it
[21:07:16 CET] <gentwo> now my results are getting on two lines, is there a way to get this in one single line? may be printformat?
[21:13:16 CET] <shincodex> pretty certain ld is just broken
[21:13:29 CET] <shincodex> and . is broken
[21:23:12 CET] <ffnoob> hello everyone, im looking for a media streaming server and wondered if ffmpeg can be used for this purpose. this is to serve rtsp streams from an encoder to end users. thanks
[21:25:59 CET] <Mavrik> nope
[21:26:10 CET] <Mavrik> ffmpeg is the encoder :)
[21:26:29 CET] <DHE> ffmpeg can feed something like an RTSP server which will do the distribution
[21:26:48 CET] <DHE> or is it RTMP... I get those confused
[21:27:08 CET] <Mavrik> both are protocols :)
[21:27:40 CET] <ffnoob> I understand ffmpeg can be used as an encoder..but wanted to know if it can be used as a server
[21:28:19 CET] <Mavrik> And the answer for that is "nope" :)
[21:28:21 CET] <ffnoob> so to distribute it I will need a media server like wowza?
[21:29:06 CET] <Croepha> anyone know why when I call avcodec_decode_video2 with new packets I dont get new frames?
[21:30:37 CET] <Phi> you'd need a key frame in there first
[21:57:39 CET] <DHE> can bitstream filters be chained?
[22:00:02 CET] <BtbN> isn't there even a meta bsf to do just that?
[23:12:19 CET] <DHE> BtbN: turns out the -help does in fact say "A comma-separated list of bitstream filters", so that's what I get for not checking first...
[23:19:11 CET] <Croepha> where can I look for options to make ffmpeg/ffplay look ahead more when streaming in content... specifically I am trying to play an hls stream, but there is a hangup when it tries to load in chunks
[23:44:27 CET] <bens218> hi
[00:00:00 CET] --- Thu Nov 10 2016