[Ffmpeg-devel-irc] ffmpeg.log.20190819

[burek]

[05:06:49 CEST] <Henry151> hiya
[05:07:07 CEST] <Henry151> I'm trying to use https://termbin.com/od69 this to burn some subtitles from an mkv into an mp4
[05:07:56 CEST] <Henry151> did a lot of my collection already (got all the bitmap subtitle stuff done) but now I forget how to do .srt subtitles. Do I have to pull them out into a .srt file first or is there some way to copy an text-based subtitle stream straight out of an mkv and burn it into an outputted mp4?
[05:08:20 CEST] <Henry151> because that attempt seems to not work as it is.
[05:10:27 CEST] <Henry151> https://bpaste.net/show/U0ML here's the full paste showing exactly the problems I'm having and what i'm attempting
[05:10:35 CEST] <Henry151> any guidance much appreciated :)
[05:16:37 CEST] <Henry151> "THUNDERBIRD," Blondie thundered.
[05:16:44 CEST] <Henry151> wrong room, oops.
[06:24:05 CEST] <pk08> hi
[06:24:28 CEST] <pk08> in showvolume filter, volume graph is too fast
[06:25:07 CEST] <pk08> and volume values (level) is too low so i am getting small audiobars
[06:25:36 CEST] <pk08> is there any way to make slow auidobar speed and higher audio level's value?
[06:26:11 CEST] <pk08> filter=: showvolume=w=1080:h=45:o=1:f=1:r=25:dm=1.0:dmc=yellow:v=0
[06:50:12 CEST] <pk08> can we get cc error, sync byte and sync loss error log in ffmepg? of mpegts
[06:51:15 CEST] <pk08> durandal_1707?
[06:51:19 CEST] <pk08> JEEB?
[07:54:38 CEST] <foobar2018> hi
[07:58:38 CEST] <foobar2018> I'm trying to take the output of my webcam to stdout, I'm making "ffmpeg -f video4linux2 -input_format mjpeg -s 640x480 -i /dev/video0 aaa.ogv" and I can get the output to a file
[07:59:14 CEST] <foobar2018> but if I make "ffmpeg -f video4linux2 -input_format mjpeg -s 640x480 -i /dev/video0 -" or "ffmpeg -f video4linux2 -input_format mjpeg -s 640x480 -i /dev/video0 pipe:0" it says "Unable to find a suitable output format for 'pipe:'"
[07:59:22 CEST] <foobar2018> What am I doing wrong?
[08:00:05 CEST] <TheAMM> You're not specifying a container
[08:00:23 CEST] <TheAMM> Use -f <something> as an output option
[08:00:44 CEST] <TheAMM> Depends on what container you actually want
[08:02:15 CEST] <foobar2018> TheAMM: " ffmpeg -f video4linux2 -input_format mjpeg -s 640x480 -i /dev/video0 -f theora - " won't even work.
[08:02:39 CEST] <TheAMM> Theora is not an output format
[08:02:43 CEST] <TheAMM> ffmpeg -formats
[08:02:53 CEST] <foobar2018> (sorry I'm not very good at this)
[08:02:59 CEST] <TheAMM> Where are you piping the data into?
[08:03:08 CEST] <foobar2018> I want to pipe to netcat
[08:03:16 CEST] <TheAMM> And netcat pipes it to?
[08:04:14 CEST] <foobar2018> to a socket, I think. I want to reply what he does in this video: https://www.youtube.com/watch?v=n4Ul_A0VBVI
[08:04:27 CEST] <TheAMM> I meant what is going to consume the data in the end
[08:04:48 CEST] <foobar2018> in the other side, vlc
[08:05:46 CEST] <TheAMM> He has -f vob in there, look closely
[08:06:23 CEST] <TheAMM> mpegts or matroska or maybe nut can work too
[08:08:31 CEST] <foobar2018> OK
[08:15:24 CEST] <foobar2018> It finally worked, but I seems I cannot open it with vlc
[08:17:24 CEST] <foobar2018> nevermind, I missed the "tcp://" at the beginning. Thank you very much.
[08:36:36 CEST] <durandal_1707> pk08: lower frame rate and use logarithmic scale?
[08:42:15 CEST] <pk08> durandal_1707: ds=1 or ds=log>
[08:42:18 CEST] <pk08> ?
[08:43:24 CEST] <durandal_1707> log
[08:44:22 CEST] <pk08> ok, thanks
[09:00:27 CEST] <Fyr> guys, why is all the porn encoded in H264?
[09:00:38 CEST] <Fyr> why does nobody use HEVC?
[09:01:34 CEST] <Fyr> how about AV1, VP9?
[09:02:11 CEST] <Fyr> why are porn producers still in the beginning of 00s?
[09:04:24 CEST] <furq> nobody is releasing stuff in av1 and nobody but youtube is releasing stuff in vp9
[09:04:57 CEST] <furq> and nobody wants to release stuff in hevc because of the horrible licensing
[09:05:19 CEST] <furq> so you pretty much universally only see it for 4k
[09:05:26 CEST] <Fyr> oh
[09:05:40 CEST] <furq> it's not vastly better than x264 at 1080p anyway
[09:06:57 CEST] <Fyr> wikipedia says that AV1 specification was released a year ago.
[09:07:07 CEST] <furq> it sure was
[09:14:41 CEST] <another> for the record: netflix is also streaming vp9
[10:48:11 CEST] <snooky> hi all
[13:12:01 CEST] <mlok> What is the best way to transcode an Origin RTMP stream that sometimes drops and results in a broken pipe with FFMPEG?
[13:15:06 CEST] <BtbN> run ffmpeg in a loop?
[13:15:34 CEST] <mlok> Tried that in a while true loop yet when I check on the stream it hangs with no message, seems to work well only with RTSP streams
[13:16:16 CEST] <BtbN> "check on the stream"?
[13:16:40 CEST] <mlok> I was thinking of perhaps generating a blank continous RTMP stream which would input the RTMP stream when available and when not it would revert to blank again until the stream is restarted, however I am not sure if that is a good way
[13:16:47 CEST] <mlok> The script is running in scree
[13:16:49 CEST] <mlok> *screen
[13:17:09 CEST] <BtbN> You will have to write custom software for that. ffmpeg.c can't do that.
[13:17:35 CEST] <mlok> Yeah...
[13:17:43 CEST] <mlok> Is it a good idea to run transcoding in screen?
[13:17:52 CEST] <JEEB> no. use services or something
[13:18:47 CEST] <mlok> Thanks, what about increasing the timeout? I did that with a RTSP stream and it worked when in a while true loop
[13:47:11 CEST] <rrva> can I enforce a certain fourcc in a output mp4 file? I want to set the fourcc dvh1 (hevc with dolby vision)
[13:49:27 CEST] <BtbN> Does mp4 even use fourcc?
[13:52:20 CEST] <rrva> or .mov files
[13:52:35 CEST] <BtbN> mp4 and mov is the same thing.
[13:52:52 CEST] <rrva> the -tag:v option
[14:03:06 CEST] <shroomM> hey
[14:04:14 CEST] <shroomM> i'm using ffmpeg to generate a hls output. single file ts, generating the master and the variant playlist
[14:04:28 CEST] <shroomM> I want to process everything via pipes. is that doable?
[14:05:25 CEST] <pk08> can I get cc errors in ffmpeg log?
[14:08:33 CEST] <shroomM> basically 3 files are output - master playlist, variant playlist and the ts file...
[15:03:58 CEST] <andrybak> hello, I'm trying to both crop and speed up a very long video. What would be faster? "setpts=0.03125*PTS , crop=717:402:0:0" or "crop=717:402:0:0, setpts=0.03125*PTS"? Or can ffmpeg choose the fastest way automatically?
[15:06:52 CEST] <DHE> they're effectively identical
[15:06:55 CEST] <Mavrik> andrybak: those two will be equivalent in performance
[15:07:15 CEST] <andrybak> Mavrik, DHE thanks
[15:07:32 CEST] <DHE> also when you say "speed up", you mean just crank the framerate right?
[15:08:32 CEST] <andrybak> I'm going by https://trac.ffmpeg.org/wiki/How%20to%20speed%20up%20/%20slow%20down%20a%20video
[15:08:44 CEST] <andrybak> and dropping frames is fine for my case
[15:15:05 CEST] <andrybak> and I'm not sure what you mean by "just crank the framerate"
[15:15:52 CEST] <Mavrik> Your code is just increasing the fps of the video by a lot
[15:24:03 CEST] <andrybak> Mavrik, sounds like that's not what I want. I want to just drop a lot of frames, and play the leftovers at ~same fps.
[15:25:01 CEST] <pagerage> Hello, I'm trying to capture both the video and audio of my desktop with ffmpeg using the command featured in the pastebin, the video works perfectly but the sound is not audible. https://pastebin.com/02vNW9jk
[16:16:36 CEST] <Henry151> can one of y'all ffmpeg wizards help me get these subtitles to be hard-coded/burnt into the outputting mp4? https://bpaste.net/show/U0ML
[16:30:08 CEST] <saml> Henry151, you need to specify subtitle
[16:31:19 CEST] <saml> ffmpeg -i a.mkv -filter_complex "subtitles=a.srt" -c:v libx264 -c:a aac a.mp4
[19:23:12 CEST] <Thomas_J> .
[19:30:00 CEST] <Thomas_J> I am having trouble getting an audio stream input going. Ive tried all sorts of things unsuccessfully. When I use "-f alsa -i hw:CARD=2,DEV=0" ffmpeg successfully launches but no audio is being input to the stream. I recompiled enabling pulse audio and with "-f pulse -i <tried every device name I could think of> but with this I get "pulse: Input/output error"
[19:31:39 CEST] <Thomas_J> The device in question is a USB audio adaptor.
[20:33:37 CEST] <rocktop> is there a way to convert video with ffmpeg to have at the end the file size is less than 64Mb ?
[20:36:04 CEST] <relaxed> rocktop: look at 2 pass, https://trac.ffmpeg.org/wiki/Encode/H.264
[20:44:39 CEST] <Foaly> hi
[20:45:03 CEST] <Foaly> i want to reduce the framerate of a video by blending multiple frames into one
[20:45:25 CEST] <Foaly> i've tried tmix followed by framestep, but that is very slow
[20:45:54 CEST] <Foaly> multiple tblend,framestep pairs are faster, but is there a better way?
[20:47:22 CEST] <BtbN> Are you sure that's a good idea? Usually that looks horrible.
[20:48:01 CEST] <BtbN> But nevertheless, putting frames together like that is a very computationally intensive operation, so it's gonna be slow.
[20:48:51 CEST] <Foaly> i have rendered an image sequence at 960 fps
[20:49:03 CEST] <Foaly> i want to merge 16 frames into one to create motion blur
[20:49:48 CEST] <pink_mist> I would expect that to look horrible
[20:50:11 CEST] <pink_mist> probably saner to just pick one of the frames and display it for 16 times as long
[20:50:45 CEST] <Foaly> it is called sampled motion blur
[20:51:24 CEST] <pink_mist> whatever you want to call it, I would expect for it to look awful
[20:51:38 CEST] <Foaly> it's how motion blur is made
[20:53:13 CEST] <BtbN> But your original question: It's crunching a lot of numbers. Not gonna be fast, ever.
[20:53:34 CEST] <Foaly> yes, but the way i do it, it's basically doing too much work
[20:53:53 CEST] <Foaly> with the framestep filter, it's just throwing away every second frame
[20:55:00 CEST] <Foaly> anyway, it finished encoding, so i guess this doesn't matter anymore
[21:00:02 CEST] <Thomas_J> I am having trouble getting an audio stream input going. Ive tried all sorts of things unsuccessfully. When I use "-f alsa -i hw:CARD=2,DEV=0" ffmpeg successfully launches but no audio is being input to the stream. I recompiled enabling pulse audio and with "-f pulse -i <tried every device name I could think of> but with this I get "pulse: Input/output error". The device in question is a USB audio adaptor.
[21:12:22 CEST] <rocktop> how to merge and put video logo on other video  with ffmpeg .?
[21:18:45 CEST] <rocktop> I used this one : ffmpeg -i video3.mp -i title.mov -filter_complex "overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2" -codec:a copy output.mp4
[21:24:31 CEST] <rocktop> how can I loop title.mov to the length of the video3.mp4 ?
[21:26:59 CEST] <rocktop> anyidea ?
[21:30:48 CEST] <BtbN> combination of -loop and -shortest
[23:46:00 CEST] <rocktop> anyidea ?
[23:47:08 CEST] <cehoyos> For what?
[23:49:15 CEST] <rocktop> I would like to place the title.mov on the video3.mp4 and loop it to the length of it
[23:49:34 CEST] <rocktop> can'tfind a good solution to acheive that
[23:52:16 CEST] <rocktop> cehoyos: ^
[23:52:17 CEST] <cehoyos> What did you try? (Command line including complete, uncut console output please.)
[23:54:18 CEST] <rocktop> I have a video3.mp4 and I have an alpha video title.mov , I would like to place and repeat title.mov  on video3.mp4
[23:54:48 CEST] <rocktop> like watermark
[23:55:18 CEST] <Aerroon> there's a loop flag
[23:56:13 CEST] <rocktop> I used this ffmpeg -i video3.mp4 -i title.mov -filter_complex "overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2" -codec:a copy output.mp4
[23:56:46 CEST] <Aerroon> here's how i did it
[23:57:04 CEST] <rocktop> this place the title.mov one time I would like to use an option to make it repeating to the length of the video3.mp4
[23:57:26 CEST] <Aerroon> i had a podcast i wanted to upload to youtube
[23:57:32 CEST] <Aerroon> so i took the podcast logo and made it into an mp4 file
[23:57:52 CEST] <Aerroon> and to quickly create the video file from just the audio file and the logo video i did this
[23:58:18 CEST] <Aerroon> ffmpeg -stream_loop -1 -i "logo.mp4" -i "audio.mp3" -shortest -c copy -r 1 "output.mkv"
[23:58:27 CEST] <Aerroon> -r 1 is framerate of 1, so you might not want that one
[23:58:39 CEST] <Aerroon> -stream_loop -1 makes it loop an infinite amount of times (that's why -shortest is needed)
[23:58:54 CEST] <rocktop> Aerroon: so with this I need to dump the audio file from video first ?
[23:59:03 CEST] <Aerroon> ???? no
[23:59:09 CEST] <Aerroon> i'm just giving an example of a related problem i had
[23:59:13 CEST] <Aerroon> you can probably do something similar
[23:59:17 CEST] <Aerroon> probably something like
[23:59:21 CEST] <rocktop> hmm
[23:59:37 CEST] <rocktop> I will try this now
[23:59:47 CEST] <Aerroon> ffmpeg -stream_loop -1 -i "logo.mp4" -i "video2.mp4" -shortest -c copy "output.mkv"
[23:59:53 CEST] <Aerroon> but i am not sure
[00:00:00 CEST] --- Tue Aug 20 2019