[Ffmpeg-devel-irc] ffmpeg.log.20150409

burek burek021 at gmail.com
Fri Apr 10 02:05:01 CEST 2015


[00:03:40 CEST] <justinX> is it possible to get a lists of how many byte is consumed per each say 10 seconds for a film? to make a nice little diagram :-)
[00:05:32 CEST] <DelphiWorld> c_14:  DES... ass                  ASS (Advanced SSA) subtitle
[00:05:39 CEST] <DelphiWorld> that mean i have ass
[00:06:01 CEST] <c_14> That means you can encode and decode ass subtitles.
[00:06:08 CEST] <DelphiWorld> ffmpeg -i resalah.mp4 -i resalah.ass -codec copy -map 0 -map 1 out.mp4 say codec not found for stream 1...
[00:06:57 CEST] <c_14> Are you sure resalah.ass is a valid ass file?
[00:07:23 CEST] <DelphiWorld> ffprobe confirm so
[00:07:27 CEST] <DelphiWorld> i didnt build it by hand
[00:07:51 CEST] <c_14> Can you pastebin the complete output + command for the one that's failing?
[00:08:08 CEST] <DelphiWorld> c_14: again how to capture the output please?
[00:08:31 CEST] <c_14> |& curl -F 'sprunge=<-' http://sprunge.us
[00:09:09 CEST] <llogan> mp4 and ass don't mix
[00:09:20 CEST] <llogan> like oil and ass.
[00:09:22 CEST] <c_14> Oh yeah, that too.
[00:09:22 CEST] <llogan> i mean water
[00:10:01 CEST] <DelphiWorld> llogan: what you recomand so!
[00:10:13 CEST] <llogan> output to mkv
[00:10:59 CEST] <DelphiWorld> c_14: http://sprunge.us/UiPL
[00:11:11 CEST] <DelphiWorld> llogan: if i want to do a mp4 file what should i output to
[00:11:54 CEST] <llogan> you could try -c:s mov_text if you want softsubs, but playback support may not work
[00:12:03 CEST] <llogan> otherwise you will have to use hardsubs
[00:12:13 CEST] <DelphiWorld> even hardsub didnt fucking work...
[00:12:41 CEST] <DelphiWorld> any good way to upload to youtube from shell?
[00:13:00 CEST] <sedulous> How do I get a WebM / libvpx file as close as possible to the desired target bitrate, using 2-pass of course?
[00:13:10 CEST] <llogan> DelphiWorld: i don't see a pasebin link to your hardsub attempt
[00:13:12 CEST] <sedulous> my results are always below -b:v ${foo}K
[00:13:52 CEST] <DelphiWorld> llogan: this is the cmd: ffmpeg -i input.mkv -vf ass=subtitles.ass output.mp4
[00:14:39 CEST] <llogan> yes, i saw that already
[00:17:16 CEST] <DelphiWorld> llogan: i want to run it now
[00:17:28 CEST] <DelphiWorld> llogan: give me a small video size please
[00:17:37 CEST] <llogan> I'm waiting for the console output
[00:17:39 CEST] <DelphiWorld> like 4... X ...?
[00:18:24 CEST] <DelphiWorld> got me llogan ?
[00:18:50 CEST] <DustyTrails> Whoop! Hello.
[00:20:12 CEST] <DustyTrails> Dunno if anybody's around, but wanted to ask a few questions about getting audio to work while streaming to Hitbox/Twitch.
[00:24:14 CEST] <ffmpeg_user> what is the highest quality preset for nvenc, to output best looking videos ? Is it "hq", or "bd" ?
[00:26:07 CEST] <DustyTrails> Oh, I think I've found my solution actually, forgot pavucontrol. Nevermind.
[00:27:31 CEST] Action: justinX kills all traces of pulseaudio with fire....
[00:27:36 CEST] <DelphiWorld> llogan: http://sprunge.us/jERi
[00:47:51 CEST] <Baked_Cake> is it ok to ask a question about moov atms and m4a files here
[00:49:53 CEST] <justinX> Baked_Cake: there is only one way to find out. if someone knows - then someone knows.
[00:50:19 CEST] <Baked_Cake> i got a file that i suspct got mega truncated
[00:51:23 CEST] <Baked_Cake> keeps saying moov atom is missing
[00:51:38 CEST] <Baked_Cake> .m4a file
[01:43:07 CEST] <justinX> I cant say I know anything about that one.
[01:51:24 CEST] <AndroUser> hi
[02:36:07 CEST] <c_14> Baked_Cake: https://github.com/ponchio/untrunc
[02:36:27 CEST] <c_14> Might not work for you, might not.
[02:36:35 CEST] <c_14> *Might work, might not.
[04:11:45 CEST] <zhaoyulong> what AV_GET_BUFFER_FLAG_REF means, does it means when libavcodec is the only referener of the chunk, then it will believe the outer user has released the chunk and can may use it freely, like a memory pool to avoid a malloc things?
[06:15:31 CEST] <Prelude2004c> [00:12] <Prelude2004c> hi everyone.. anyone know if there is an ffmpeg encoding limit of 120fps ?
[06:15:31 CEST] <Prelude2004c> [00:12] <Prelude2004c> i can't seem to encode anything above 120fps on a multi output stream
[06:15:31 CEST] <Prelude2004c> [00:13] <Prelude2004c> if i run the ffmpeg individually like ( 60fps ) each stream * 5 streams, it works fine
[06:15:31 CEST] <Prelude2004c> [00:13] <Prelude2004c> anyone have any clues..
[06:15:31 CEST] <Prelude2004c> [00:13] <Prelude2004c> when i run ffmpeg once with Multi out it is not fine
[08:13:16 CEST] <gopi> Hey, I am trying to capture the video using Blackmagic Deckling Mini Recorder.
[08:14:39 CEST] <gopi> I have successfully compiled the Blackmagic SDK with ffmpeg..
[08:15:04 CEST] <gopi> It also capture, but i get black screen for video..
[08:15:32 CEST] <gopi> I get this message " Frame received (#1) - No input signal detected - Frames dropped 1"
[08:24:20 CEST] <gopi> http://pastebin.com/qcSjxC6B
[08:24:36 CEST] <gopi> has anyone come across this issue?
[10:38:48 CEST] <dAnjou> hi, i have a video here that has incorrect dimensions in its metadata. it displays correctly in ffplay though. is there any decent way to get the actual dimensions?
[10:39:27 CEST] <dAnjou> ffprobe only shows the metadata apparently
[12:03:19 CEST] <debianuser> dAnjou: It's probably due to aspect ratio. When playing such file by mplayer you'd see something like "704x576 => 1024x576". You can see SAR and DAR in ffprobe output (though I'm not sure how to translate it into a final resolution).
[12:16:11 CEST] <brum> while building my application on solaris i get an error " avcodec_free_context was not declared in this scope ", Any idea where the problem could be?
[12:16:23 CEST] <brum> same build works on windows just fine
[12:32:35 CEST] <z3bra> Hi!
[12:33:15 CEST] <z3bra> I'm trying to record my desktop directly into webm, using the following command: ffmpeg -f x11grab -s 1440x900 -framerate 25 -i :0.0 -y -vcodec libvpx -f webm -b:v 1M file.webm
[12:33:34 CEST] <z3bra> but it creates a video which plays extremely fast
[12:34:18 CEST] <z3bra> or a video that drops many frames, so which isn't smooth
[12:34:54 CEST] <z3bra> I pasted the wrong command, here is the command that creates accelerated videos
[12:34:58 CEST] <z3bra> ffmpeg -f x11grab -s 1440x900 -c:v libvpx -an -r 16 -loglevel quiet ->i :0.0 -b:v 5M -y file.webm
[12:35:10 CEST] <z3bra> the more I increase the -r param, the faster it gets
[12:36:08 CEST] <z3bra> it's like ffmpeg isn't able to record webms at 25 FPS, and so, drops a few frames, and make it 25fps afterwards
[12:39:29 CEST] <z3bra> If I replace file.webm by file.mp4, it works great
[13:11:57 CEST] <debianuser> z3bra: Maybe libvpx is too slow to encode in realtime? To test that grab it in mp4+x264 first: `ffmpeg -f x11grab -s 1440x900 -r 25 -i :0.0 -vcodec libx264 -preset ultrafast file.mp4` and then check how fast it can reencode that to webm+libvpx with your command: `ffmpeg -i file.mp4 -c:v libvpx -b:v 5M file.webm`
[13:17:01 CEST] <brotherBox> z3bra: it might be related to your player actually, do you play it with mplayer?
[13:17:05 CEST] <z3bra> I tried with mkv
[13:17:08 CEST] <z3bra> and yeah it's slow
[13:17:19 CEST] <z3bra> brotherBox, yeah with mplayer
[13:17:26 CEST] <z3bra> but it's not only on my side
[13:17:44 CEST] <brotherBox> z3bra: try to play the webm with vlc. i had the same situation and vlc would play it flawlessly
[13:17:54 CEST] <debianuser> If file.mp4 -> file.webm encoding would be like 15fps then you've got the explanation why it was slow with x11grab :)
[13:18:31 CEST] <debianuser> maybe there're some options for libvpx to make encoding faster?
[13:34:17 CEST] <z3bra> brotherBox, could you try for me please?
[13:36:48 CEST] <z3bra> http://raw.z3bra.org/vid/linux/launcher.webm
[13:37:02 CEST] <z3bra> ^ this is an example vid I recorded with the command I gave
[13:39:11 CEST] <brotherBox> z3bra: it says in the bottom right it only records 8fps
[13:39:52 CEST] <z3bra> yeah I know
[13:39:55 CEST] <z3bra> that's my problem
[13:39:56 CEST] <brotherBox> I mean left
[13:40:03 CEST] <z3bra> I can't make it record at 25 FPS
[13:40:35 CEST] <brotherBox> my point is: its not related to the player
[13:40:48 CEST] <z3bra> yeah
[13:48:22 CEST] <debianuser> z3bra: It seems there's a "realtime" switch for libvpx. Try it with files first: `ffmpeg -i file.mp4 -c:v libvpx -crf 10 -quality realtime file.webm` and check if it would work faster for you
[13:48:55 CEST] <z3bra> lets find out :)
[13:49:35 CEST] <z3bra> ...
[13:49:37 CEST] <z3bra> It works :D
[13:50:40 CEST] <z3bra> the -crf 10 actually doesn't matter it seems
[13:51:14 CEST] <debianuser> https://trac.ffmpeg.org/wiki/Encode/VP8 says it should matter, but maybe -quality switch has a higher priority.
[13:53:11 CEST] <debianuser> For libx264 "-crf" switch is like a "constant quality". "-crf 0" is lossless but large size, "-crf 51" is small size but very poor quality. I guess it's similar for libvpx
[13:53:27 CEST] <z3bra> thanks for the info
[13:54:08 CEST] <z3bra> it seems that libvps can't handle -crf 0
[13:54:15 CEST] <z3bra> it throws an error
[13:55:56 CEST] <z3bra> anyway, thanks a lot for your help :)
[13:56:33 CEST] <z3bra> I finally have the ultimate screencast command ;)
[13:56:34 CEST] <z3bra> alias rec='ffmpeg -f x11grab -s 1440x900 -an -i :0.0 -c:v libvpx -b:v 5M -crf 10 -quality realtime -y'
[13:56:47 CEST] <debianuser> :)
[13:57:11 CEST] <debianuser> You're welcome. I'm glad I could help
[14:12:11 CEST] <t4nk640> hello
[14:13:16 CEST] <t4nk640> can anyone please provide a ffmpeg compiled library code that supports Android Api 8+ to now(lollipop)
[14:15:33 CEST] <DelphiWorld> c_14: be happy, burning subtitle worked
[14:18:40 CEST] <dAnjou> debianuser: thanks
[14:18:50 CEST] <z3bra> I'm off,
[14:18:59 CEST] <z3bra> bye, and thanks again for your help :)
[14:24:15 CEST] <debianuser> dAnjou: It seems to work like this: get, "width", "height" and "dar" from ffprobe; if width/height<dar then final resolution is "height*dar" x "height" else final resolution is "width" x "width/dar"
[14:44:57 CEST] <DelphiWorld> ffmpeg -re -i http://live.noorlive.com:1935/wesal/wesal1/playlist.m3u8 -vn -acodec copy icecast://[source[:pass]@]localhost:8000/wesal
[14:45:07 CEST] <DelphiWorld> is this correct to be  able to broadcast to icecast?
[14:47:31 CEST] <dAnjou> DelphiWorld: did you run it with *this* icecast URL?
[14:48:08 CEST] <dAnjou> the URL contains placeholders
[14:49:18 CEST] <DelphiWorld> ffmpeg -re -i http://live.noorlive.com:1935/wesal/wesal1/playlist.m3u8 -vn -acodec copy icecast://[source:pass@localhost:8000/wesal
[14:49:22 CEST] <DelphiWorld> so its correct?
[14:52:31 CEST] <dAnjou> no
[14:52:48 CEST] <dAnjou> don't guess. understand, then do.
[14:53:24 CEST] <DelphiWorld> the issue is that icecast:// is not supported
[14:53:29 CEST] <DelphiWorld> but yes, this should be correct: ffmpeg -re -i http://live.noorlive.com:1935/wesal/wesal1/playlist.m3u8 -vn -acodec copy icecast://source:pass@localhost:8000/wesal
[14:59:59 CEST] <DelphiWorld> ffmpeg -re -i http://live.noorlive.com:1935/wesal/wesal1/playlist.m3u8 -vn -acodec copy icecast://source:pass@localhost:8000/wesal
[15:00:06 CEST] <DelphiWorld> still saying icecast:// not knowne
[15:03:19 CEST] <seshan> Hi all
[15:04:34 CEST] <seshan> I have a situation where we want to generate a low res video as a preview video for the high res video uploaded
[15:04:53 CEST] <seshan> possible uploaded formats mov mpeg or mp4
[15:05:32 CEST] <Mavrik> yay? :)
[15:05:39 CEST] <seshan> output preferrably in webm or any browser playable format (firefox)
[15:07:40 CEST] <dAnjou> *thumbsup*
[15:08:26 CEST] <Mavrik> seshan, sooooo... what's your question? :)
[15:08:28 CEST] <dAnjou> seshan: have fun
[15:09:12 CEST] <dAnjou> Mavrik: aww, i thought you'd let him wait a little longer :P
[15:09:23 CEST] <seshan> @Mavrik Trying out various ways to get the lowest possible sized video
[15:09:33 CEST] <seshan> Trying out now ffmpeg -i a.mp4 -vf scale=iw/2:- a.webm
[15:10:09 CEST] <seshan> @dAnjou Already one day with ffmpeg and fun :) What more I need
[15:10:22 CEST] <Mavrik> I suggest you read the wiki first
[15:10:38 CEST] <Mavrik> https://trac.ffmpeg.org/wiki/Encode/VP8
[15:13:01 CEST] <dAnjou> seshan: do you need audio? if not -an
[15:17:18 CEST] <seshan> audio yes !
[15:29:19 CEST] <DelphiWorld> dAnjou: LOL. switched to rtmp
[15:30:58 CEST] <dAnjou> ROFL
[16:35:44 CEST] <iPito> Hello! Is there a way to capture a frame from video (screenshot) from for example the middle of the video? I have an working command that captures a still at x seconds from the beginning and I'd like to modify it in a way i said before
[16:56:30 CEST] <hydalgo> hi I'm trying to use pnacl ffmpeg port to encode a video from camera stream and storing using pp:FileSystem apis, but don't know how to pass the handle to the file to ffmpeg. the method avcodec_open2 receives a file path so it fails.
[17:08:00 CEST] <Mavrik> hydalgo, you'll probably have to define your own AVIOContext
[17:17:15 CEST] <hydalgo> @Mavrik thank you for the hint, going to research in that address
[17:17:33 CEST] <Mavrik> hydalgo, AVIOContext is the structure that points to methods that read/write to files
[17:17:50 CEST] <Mavrik> so you basically implement a read function that will read from your source
[17:20:10 CEST] <hydalgo> @Mavrik oh I see! that makes a lot of sense I was afraid of complications due to that google-chrome nacl requires the IO happens in another thread but I suppose that I can encapsulate threading in the method. hope it would be more tutorials on this topic on the net :)
[17:20:43 CEST] <Mavrik> hmm
[17:20:47 CEST] <Mavrik> I'm afraid there's nothing much
[17:21:43 CEST] <hydalgo> yes, for ffmpeg c++ is very hard to found updated material.. not to mention sub-topics like ffmpeg+pnacl
[17:22:06 CEST] <Mavrik> of course, because noone used it yet
[17:22:17 CEST] <Mavrik> first of all, you probably thought avformat_open_input not avcodec_open2
[17:23:24 CEST] <hydalgo> there are some google-chrome extensions that actually use that, I have to implement one on my own..
[17:23:28 CEST] <Mavrik> and to use custom input you need to set AVFormatContext->pb to your custom AVIOContext (you get it by calling avio_alloc_context with proper function pointers)
[17:24:03 CEST] <hydalgo> thank you again, you are providing me more useful information that many hours of googling :)
[17:29:14 CEST] <juzzlin_> Hi, does anyone know why my encoding of jpgs to x265 fail when I'm using multiple files like this -i %04d.jpg even if there's only one image? Everything works if I hard-code the path of the image and the command is otherwise the same.
[17:29:29 CEST] <juzzlin_> [mjpeg @ 0x41786b80] mjpeg: unsupported coding type (cf)
[17:29:40 CEST] <juzzlin_> [mjpeg @ 0x41786b80] mjpeg: unsupported coding type (c8)
[17:29:58 CEST] <juzzlin_> wtf..
[17:30:37 CEST] <juzzlin_> -i 0001.jpg works just fine
[17:48:44 CEST] <c_14> juzzlin_: are you sure the input is a jpg?
[18:04:05 CEST] <iPito> Hello! I'm having problems with cropping a screenshot from video that has been scaled down to 142x80. I'd like to have a 80x80 image from that 142x80 image, but something's wrong with my code and i get cops of full resolution image. Any suggestions? Here's the code: http://pastebin.com/pK96zQpr
[18:33:31 CEST] <c_14> The scale isn't applying to the pictures you're cropping.
[18:34:15 CEST] <c_14> Change the second filter:v to "scale=142:-1,crop=80:80:71:40"
[18:41:27 CEST] <iPito> Made these changes and now everything works as i expected :) Thanks.
[18:43:22 CEST] <iPito> I forgot to ask: is there a way to bymp the quality of these .jpg's a little, because i can see some blocking in my images.
[18:43:27 CEST] <iPito> *bump
[18:43:33 CEST] <c_14> -q:v 0-4
[18:43:36 CEST] <c_14> lower is better
[18:43:44 CEST] <c_14> I think it's 0-4 anyway.
[18:43:46 CEST] <c_14> 0-x
[18:44:27 CEST] <iPito> and that needs to go after the -ss?
[18:45:27 CEST] <c_14> Eh, between 1-31. And after the last -i before each jpg outpet
[18:45:30 CEST] <c_14> *output
[18:51:09 CEST] <iPito> Ok, everything works. Thanks for help.
[20:27:28 CEST] <selsta> are there examples that use a custom AVIOContext and the write_packet() function? I can open an input from memory, but cant open an output to memory.
[21:43:04 CEST] <DragonsLord> Hi guys, could some explain what does "Warning: data is not aligned! This can lead to a speedloss" mean?
[21:51:57 CEST] <iive> if you use ffmpeg, you can ignore it
[21:52:27 CEST] <iive> it basically means that the image passed to swscale start from address that is not multiple of 8.
[21:52:52 CEST] <iive> SSE have instruction that can load faster memory when data is aligned to 8 bytes.
[21:53:15 CEST] <iive> load memory faster/
[21:53:18 CEST] <DragonsLord> iive, thank you for your reply but it's not my case
[21:53:28 CEST] <DragonsLord> I used scale=w=640:h=480
[21:53:38 CEST] <DragonsLord> they are both multiple of 8
[21:54:13 CEST] <iive> yes. unless you use libavswscale directly as C library, there is nothing you can do.
[21:54:25 CEST] <iive> ignore it, the slowdown is small.
[21:54:44 CEST] <iive> worst case, it would be using mmx.
[21:56:06 CEST] <DragonsLord> with slowdown you mean when the conversion process is running
[21:56:20 CEST] <DragonsLord> or when I will play the resulting file?
[22:00:29 CEST] <DragonsLord> iive, are you still there?
[22:02:20 CEST] <iive> convertion
[22:02:30 CEST] <iive> specifically, when resizing.
[22:02:58 CEST] <iive> you can ignore it.
[22:03:06 CEST] <DragonsLord> OK but, just to understand
[22:03:35 CEST] <DragonsLord> is it a bug, since my scaled w/h are multiple of 8 and 16?
[22:04:10 CEST] <DragonsLord> and, futhermore, the resulting file will be perfectly fine?
[22:12:48 CEST] <iive> yes it would be fine
[22:13:01 CEST] <iive> it is not about width/height.
[22:13:16 CEST] <iive> it is about the start of the image buffer. you have no control over it.
[22:13:56 CEST] <DragonsLord> But is it a bug that needs to be fixed?
[22:14:00 CEST] <iive> no
[22:14:19 CEST] <DragonsLord> hi llogan
[22:14:35 CEST] <DragonsLord> so, sorry iive  but I did not understand
[22:14:51 CEST] <iive> sometimes the start could be changed by e.g. crop filter, that avoid copying the whole image.
[22:14:51 CEST] <DragonsLord> Has my source file some trouble?
[22:14:56 CEST] <iive> NO
[22:15:04 CEST] <llogan> DragonsLord: greetings and salutations
[22:15:33 CEST] <DragonsLord> OK, fine
[22:15:48 CEST] <DragonsLord> and my ffmpeg instructions are also fine, right?
[22:15:54 CEST] <iive> sure
[22:16:10 CEST] <DragonsLord> then, the resulting file too
[22:16:32 CEST] <DragonsLord> so, jumping (finally) to the conclusion ... it's an unusefull warning
[22:17:13 CEST] <iive> yes
[22:17:27 CEST] <DragonsLord> Excellent, very good
[22:17:45 CEST] <DragonsLord> I was suspecting one error by me
[22:17:56 CEST] <DragonsLord> Happy to know this is not the case
[22:17:57 CEST] <DragonsLord> :)
[22:52:10 CEST] <sg90> Hi, I'm having some issues using -timecode, the segment muxer and using reset_timestamps. I segment a live stream every 30 seconds and can inject a custom timecode for the first segment. By default, the second segment has 30 seconds of blank video, then the clip starts at the correct timecode. However I require all segments to be playable from the start of each segment. Using reset_timestamps 1 fixes this but resets the timecode to my f
[22:53:17 CEST] <sg90> Is there another way to trim the segments to the correct start point while they are being created?
[23:49:44 CEST] <DragonsLord> iive, can the Warning before bring FFmpeg to cause cropping problems?
[23:56:46 CEST] <iive> no
[23:57:12 CEST] <iive> i mentioned it, because there is a trick used for cropping, that doesn't actually move the data.
[23:57:42 CEST] <iive> e.g. if you crop by 4 pixels, it just moves the buffer start by 4 bytes, and lowers the width.
[23:58:00 CEST] <iive> this way you can end up with unaligned buffer.
[00:00:00 CEST] --- Fri Apr 10 2015


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