[Ffmpeg-devel-irc] ffmpeg.log.20150616

burek burek021 at gmail.com
Wed Jun 17 02:05:01 CEST 2015


[00:05:43 CEST] <podman> so what happened to ffmpeg.org?
[00:12:24 CEST] <Nolski> Hey all, I'm a bit new to ffmpeg and I'm trying to skip or cut out sections of a clip (like play 0-30 and 45-end but not 30-45)
[00:14:00 CEST] <Nolski> I found an example of a command which seems to demonstrate it by using trim and concat but it seems to trim in two spots and I was wondering if someone could help break it down for me. http://fpaste.org/232361/40640214/
[00:14:58 CEST] <techtopia> your better off cutting before hand with another app then encoding a solid file with ffmpeg
[00:15:15 CEST] <techtopia> but you can use -ss to mark the start point of the encode
[00:15:24 CEST] <techtopia> and -t to specify a duration
[00:18:59 CEST] <Nolski> techtopia: Unfortunatly the entire file has to be processed with ffmpeg. The application I'm writing is using ffmpeg to encode video edits from a web editor into a flat video file
[00:21:03 CEST] <Nolski> From the snippet it looks like it seeks to 30 seconds (trim=duration=30) skips to 40 seconds (trim=start=40) but I'm not really sure what STARTPTS is for
[00:21:08 CEST] <pzich> is that trim and concat command not working, or you're just trying to understand it?
[00:21:22 CEST] <Nolski> pzich: I'm just trying to understand it
[00:21:41 CEST] <Nolski> (it works)
[00:22:33 CEST] <Nolski> Oh also, I'm not sure if anyone here is hosting ffmpeg.org but it seems that the website is down (connecting from California in the US)
[00:22:52 CEST] <pzich> and how familiar are you with the details of video encoding? the PTS is a technical thing that you don't necessarily need to understand
[00:23:04 CEST] <pzich> yeah, I think there are ongoing issues with the site ATM
[00:24:11 CEST] <Nolski> pzich: just the basics.
[00:25:30 CEST] <pzich> it's probably not worth getting into the details, but basically in this case you need it when you're not starting at the start, e.g. seeking with a start time in trim
[00:27:10 CEST] <Nolski> Ahhh I see.
[00:29:06 CEST] <Nolski> pzich: so on line 2, it says trim=duration=30 but it looks like it only cuts out 10 seconds (starting at the 30 second mark). Is that line just seeking to the 30 second mark?
[00:31:57 CEST] <pzich> it's trimming from 0 to 30 seconds (and keeping it)
[00:32:11 CEST] <pzich> it's cutting out 10 seconds because the next trim starts at 40 and 40 - 30 = 10
[00:34:20 CEST] <Nolski> Ooooh! I get it!
[00:34:35 CEST] <Nolski> drawing this stuff out on paper helps. Thanks pzich!
[00:35:14 CEST] <pzich> no problem
[01:00:30 CEST] <Zeranoe> Has anyone experimented with livestreaming HTML5 video with FFmpeg?
[01:48:15 CEST] <Jekar> Evening all! So, I am completely new to using ffmpeg and so far it's been fairly straightforward. I was just looking for some advice to reduce lag/frame drop when grabbing audio/video from games. I'm using the following command:
[01:48:39 CEST] <Jekar> ffmpeg -f alsa -ac 2 -i pulse -f x11grab -r 30 -s 1024x768 -i :0.0 -acodec pcm_s16le -vcodec libx264 -preset ultrafast -crf 0 -threads 0 (my-output).mkv
[02:36:56 CEST] <voip_> hello guys
[02:37:51 CEST] <voip_> did you try use ffmpeg on Rasbery pi board as live stream transcoder h264?
[03:23:42 CEST] <zachary> What is the difference between `-r` and `-framerate`?
[03:23:54 CEST] <zachary> I cannot find information on the official site.
[03:38:08 CEST] <roboman2444> i think one of them is related to input fps
[03:39:24 CEST] <c_14> Both are/can be. -r is the general option to override input fps detection, -framerate is an option specific to several demuxers that sets the fps
[03:42:21 CEST] <zachary> ambiguous
[03:42:36 CEST] <zachary> why the official site don't give a explanation
[03:42:44 CEST] <c_14> Use -framerate for the demuxers that support it, otherwise use -r
[03:44:09 CEST] <c_14> >As an input option, ignore any timestamps stored in the file and instead generate timestamps assuming constant frame rate fps.  This is not the same as the -framerate option used for some input formats like image2 or v4l2 (it used to be the same in older versions of FFmpeg).  If in doubt use -framerate instead of the input option -r
[03:44:32 CEST] <kyleogrg> hello
[03:45:00 CEST] <kyleogrg> I have a question, probably simple, about an interlaced/IVTC DVD.
[03:45:11 CEST] <kyleogrg> It's a PAL-region DVD.
[03:45:46 CEST] <kyleogrg> I frame-stepped through a small portion in VLC and came up with this pattern (1 = looks interlaced, 0 = doesn't):
[03:45:50 CEST] <kyleogrg> 10000000000000011111111111100000000000001111111111110
[03:46:20 CEST] <Kuukunen> zachary: ffmpeg -h full  gives you something
[03:46:25 CEST] <kyleogrg> What is this pattern?
[03:48:51 CEST] <zachary> Kuukunen: so for input device, use -framerate is a secure option
[03:49:21 CEST] <Kuukunen> zachary: for the demuxers that have it
[03:49:24 CEST] <Kuukunen> I guess
[03:50:50 CEST] <kyleogrg> Could this pattern be a 2:2 pulldown?
[03:52:19 CEST] <kepstin> kyleogrg, looks like a 25:24 pulldown to me
[03:52:29 CEST] <kepstin> a 2:2 pulldown looks like constant progressive video
[03:52:55 CEST] <kyleogrg> Yes.  I have several PAL DVDs, and they look progressive, except this one.
[03:53:12 CEST] <kepstin> this looks like they tried to change the video to 50 fields per second at the same speed, rather than speed up from 24 to 25fps like most films.
[03:53:13 CEST] <kyleogrg> You're saying maybe this was converted from 25 to 24?
[03:53:21 CEST] <kepstin> from 24 to 25
[03:53:38 CEST] <kyleogrg> hmm.  this is a double-sided dvd -- the other side is ntsc
[03:54:20 CEST] <kyleogrg> i know you can IVTC with NTSC
[03:54:24 CEST] <kepstin> then rip the ntsc one, it might be easier. probably a standard 3:2 pulldown
[03:54:40 CEST] <kepstin> (use the 'pullup' or 'filmdint' filters with default options to reverse that)
[03:55:02 CEST] <kyleogrg> can the 25:24 pulldown be undone?
[03:55:31 CEST] <kepstin> sure, but you'll have to play around with the detelecining filters to convince them to do it.
[03:55:39 CEST] <kyleogrg> sure
[03:55:55 CEST] <kepstin> and it's not something i've done before, living in north america as i do ;)
[03:56:07 CEST] <kyleogrg> haha so do i
[03:58:44 CEST] <kyleogrg> what's the format for specifying a custom detelecine pattern (in handbrake, for example)?
[04:38:56 CEST] <zachary> Cannot grab x11 Desktop: http://pastebin.com/4gXu48L6
[04:39:08 CEST] <zachary> which part should I modify my screen
[04:39:26 CEST] <zachary> which parameters should I modify
[04:50:05 CEST] <Quixxx> Is a lower crf higher quality?
[04:55:12 CEST] <Devrim> yes
[05:04:21 CEST] <chungy> zachary: check your audio input
[05:04:35 CEST] <zachary> my audio input is OK.
[05:04:54 CEST] <chungy> ffmpeg isn't finding it ok
[05:05:25 CEST] <chungy> double-check "ffmpeg -sinks" to see what you have. looks like you have wrong options there.
[05:05:31 CEST] <zachary> chungy: when I remove the `scale=w=iw/2:h=ih/2` part, it works now.
[05:06:05 CEST] <zachary> chungy: what -sinks does?
[05:06:15 CEST] <chungy> list the sinks on your system
[05:06:28 CEST] <Quixxx> I don't have any sinks, my PC is air cooled
[05:06:34 CEST] <Quixxx> c:
[05:07:01 CEST] <chungy> also 1362x766 sounds like you're working around an ffmpeg bug with x11grab :P
[05:07:27 CEST] <zachary> chungy: what does it mean? My screen resolution is 1366*768
[05:07:48 CEST] <zachary> chungy: so i specify the video_size to 1362*766
[05:08:23 CEST] <zachary> chungy: the small reduction is that x11grab cannot find position 0,0 on screen.
[05:08:29 CEST] <chungy> Right; the tip of the release/2.6 branch has a fix for that.
[05:09:16 CEST] <zachary> chungy: you are right. If I change 1362*768 to 1280*720, it also works.
[07:27:06 CEST] <apaul> I am using ffmpeg commandline to extract pts_time and save them in log.txt file.I want to know how can I append current system time in front of each pts_time value.
[07:27:36 CEST] <apaul> here is command:  ffmpeg -i rtsp://192.168.0.127 -vstats_file vstats.log -map 0:0 -map 0:1 -s 640x360 -vcodec libx264 -g 60 -vb 500000 -filter:v "showinfo" -strict experimental -an -y -f segment -segment_time 20 "part-%03d.ts"   2>&1  | grep pts_time | awk '{print $8}'| tee log.txt | grep pts_time
[07:57:25 CEST] <apaul> Anoia: I am using ffmpeg commandline to extract pts_time and save them in log.txt file.I want to know how can I append current system time in front of each pts_time value.
[07:57:26 CEST] <apaul> <apaul> here is command:  ffmpeg -i rtsp://192.168.0.127 -vstats_file vstats.log -map 0:0 -map 0:1 -s 640x360 -vcodec libx264 -g 60 -vb 500000 -filter:v "showinfo" -strict experimental -an -y -f segment -segment_time 20 "part-%03d.ts"   2>&1  | grep pts_time | awk '{print $8}'| tee log.txt | grep pts_time
[08:17:52 CEST] <roboman2444> im using libavcodec, and the only input format it will allow me to do is YUV420P
[08:18:12 CEST] <roboman2444> can i use BGRA or other as an input pixel format when encoding with h264 or mpeg1video?
[09:10:21 CEST] <durandal_1707> for rgba use libx264rgb encoder
[09:47:41 CEST] <termos> is sample size the same as AVCodecContext::frame_size in libffmpeg?
[09:54:46 CEST] <termos> oh, it's of course specified by the sample format
[09:55:42 CEST] <baadf00d> Hello. I'm trying to sync multiple video streams from different rtsp servers by the wallclock time. I'm using libVLC to play the video, and it doesn't support reading creation_time metadata. Is there any way to save the start time of the video in some other place
[09:55:54 CEST] <baadf00d> filename for example
[09:56:33 CEST] <baadf00d> I found this https://ffmpeg.org/pipermail/ffmpeg-user/2014-March/020393.html But it didnt' seem to work
[10:01:22 CEST] <baadf00d> One thing i'm wondering, how can i verify that my file has the correct value in start_time_realtime? http://ffmpeg.org/doxygen/trunk/structAVFormatContext.html#aa5ddb5cee1df28f21739133f2e37f1c5
[10:01:41 CEST] <baadf00d> I didn't find a way to see if ffprobe gave it somehow
[10:06:24 CEST] <Anoia> apaul: your question is unrelated to ffmpeg, you just need to append the time int he awk string, but they'll all have the time you run the command
[10:09:14 CEST] <ac_slater_> curious, what happens if I give a mux (output) context a stream with a weird timebase? Or, rather, what if I have a container like MPEGTS and I have a stream with 25/1 and another with 72/1 ?
[10:33:37 CEST] <anshul_> I am using yuv file in input, ffmpeg gives warning Past duration 0.639992 too large
[10:34:32 CEST] <anshul_> I suppose there are no timestamp in my yuv file, then what is  sense of pastduration warning
[10:46:39 CEST] <anshul_> this warning come when i give x264opts level=4.0
[10:49:14 CEST] <anshul_> sry i was wrong those warning are when I give -r 25
[13:50:51 CEST] <feliwir> hey, i asked this a couple days ago already, but does someone here still have libvp62 on his pc by any chance?
[13:58:17 CEST] <xtemp09> guys, I've posted a bug (something incredibly simple). when should I expect it be fixed? I looked through open bugs and lost my courage. =(
[14:07:02 CEST] <apaul> how to get output filename from OutputFile structure in ffmpeg.c code
[14:07:49 CEST] <apaul> I am using OutputFile *file ; file->ctx->filename ;
[14:41:54 CEST] <anshul_> apaul: what is it you trying to do
[14:46:11 CEST] <anshul_> in ffmpeg if i use ultrafast h264 preset then in H264 sps it says that profile is Main
[14:47:47 CEST] <anshul_> since in utlrafast dct8x8 is not selected and in h264 while making sps it check for dct8x8 or i_cqm_preset
[14:48:12 CEST] <BtbN> x264 ultrafast should result in contstrained baseline
[15:25:36 CEST] <anshul_> BtbN: thanks
[15:29:22 CEST] <anshul_> BtbN: is it ok to use level 4.1 and constrained baseline if my target device where video would play is ios
[15:29:56 CEST] <anshul_> since they say that u should use High profile with level 4.1
[15:30:57 CEST] <BtbN> Is that combination even legal?
[15:32:50 CEST] <anshul_> till now I was using profile high and level 4.1 with preset ultrafast, but in sps of output profile was not high.
[15:33:06 CEST] <anshul_> Even I have the same question is that combination legal
[15:33:15 CEST] <BtbN> ultrafast implies contrained baseline, as you turn off requires features for high and main
[15:33:21 CEST] <BtbN> *d
[15:34:10 CEST] <anshul_> do I need get rid of utlrafast if I have to make high and level4.1
[15:34:38 CEST] <BtbN> There's no point in that combination
[15:36:07 CEST] <anshul_> BtbN: can u elaborate? should I get rid of high profile or ultrafast
[15:36:18 CEST] <BtbN> Whatever you want
[15:38:18 CEST] <anshul_> i choose high profile since I selected 4.1 level, and apple peoples say we support 4.1 with high profile, ultrafast I chose since I want to encode videos faster
[15:38:51 CEST] <BtbN> ultrafast disabled most features, to be fast
[15:38:58 CEST] <BtbN> so it ends up at constrained baseline
[15:39:02 CEST] <BtbN> and basicaly mpeg2 quality
[15:39:25 CEST] <anshul_> Would there be any problem on ios player with level 4.1 and constrained baseline
[15:39:32 CEST] <BtbN> ...
[15:40:16 CEST] <anshul_> I dont have access to all kind of decoders given by ios
[15:40:32 CEST] <anshul_> to test, so just want to be on safe side
[15:40:51 CEST] <BtbN> I just told you that i don't think that it even is a valid combination.
[15:57:01 CEST] <anshul_> BtbN: thanks again
[16:28:27 CEST] <Fyr> guys, is it possible to process audio multithreadedly? I have a large FLAC (~1 Gb) that I want to recompress. I have 12-cored Xeon cluster, but ffmepg uses only 100% of the cluster. ='(
[16:32:07 CEST] <Fyr> I've converted into WAV and now I am trying to convert into FLAC back with turned all the compress options on.
[16:34:04 CEST] <c_14> Fyr: according to the help output, the flac encoder doesn't thread
[16:34:17 CEST] <Fyr> ='(
[16:34:49 CEST] <Fyr> is it feasible to have it multithreaded?
[16:34:57 CEST] <Fyr> is libflac support multiple threads?
[16:35:08 CEST] <Fyr> *does
[16:35:30 CEST] <c_14> According to the libflac api docs it does not thread either.
[16:35:42 CEST] <Fyr> it's too sad.
[16:36:00 CEST] <c_14> There was apparently a proof of concept on the Flac-dev ml
[16:38:39 CEST] <c_14> The patches 404 of course.
[16:40:52 CEST] <spectromas> what does ffmpeg do if I don't specify a -crf value? I can't find any info about what level is used instead, the default 23?
[16:41:33 CEST] <c_14> libx264 defaults to a crf of 23, yes
[16:41:53 CEST] <spectromas> ok thank you
[16:42:08 CEST] <Fyr> I hope Xiph will buy a multicored computer to their employees.
[16:42:17 CEST] <c_14> Fyr: I found copies of the patches that don't 404 along with the relevant blog post. http://www.akalin.cx/parallelizing-flac-encoding if you're interested. Probably a lot of work to get it working 100% though.
[16:42:54 CEST] <Fyr> oh
[16:43:09 CEST] <Fyr> too old libFLAC =(
[17:13:08 CEST] <Netek> is there anyway I can run ffmpeg in background on ubuntu?
[17:14:15 CEST] <Fyr> screen/tmux
[17:14:23 CEST] <Fyr> use tmux, Netek.
[17:15:00 CEST] <hardikj> hi, I am using 'ffmpeg -framerate 8  -f gdigrab -vcodec libx264 -crf 0  -preset ultrafast output.mkv' to capture my screen, is there any way to reduce the cpu usage
[17:15:17 CEST] <hardikj> does the output format like ".mkv" affect the cpu usage?
[17:15:20 CEST] <Fyr> hw encoding?
[17:15:52 CEST] <Fyr> hardikj, have you tried to recomile it with dxva2 enabled? or nvenc?
[17:16:59 CEST] <hardikj> Fyr, thanks for quick response, by recompling you mean running again on same output
[17:17:20 CEST] <Fyr> no, I meant recompilation.
[17:17:43 CEST] <Fyr> http://its.ffmpeg.org/wiki/CompilationGuide
[17:18:07 CEST] <hardikj> ah, nice
[17:18:17 CEST] <hardikj> let me try that :)
[17:18:56 CEST] <damnlie> hi, may i have a question, im running ffmpeg N-72812 on debian 8.1 now im coming a cros with a problem  Unknown encoder 'libx264'
[17:19:25 CEST] <Fyr> if I were you, I would use something more convenient than ffmpeg, for example - OBS.
[17:19:32 CEST] <Fyr> hardikj
[17:20:22 CEST] <Fyr> damnlie, have downloaded ffmpeg from the website or compiled it on your own?
[17:20:33 CEST] <damnlie> from git
[17:20:47 CEST] <Fyr> did you compile it with libx264?
[17:21:40 CEST] <hardikj> Fyr, I am looking for a tool that will be used to record selenium test running on 1000 windows/mac box. For Mac box ffmpeg works out of the box
[17:21:49 CEST] <trosh> ( ./configure ... --enable-libx264 ... )
[17:22:04 CEST] <hardikj> but some window box have 1 core and 2 gb ram
[17:22:11 CEST] <Fyr> hardikj, OBS is the right choice.
[17:22:27 CEST] <hardikj> Fyr, ok will look into it
[17:22:30 CEST] <hardikj> thanks for help
[17:32:17 CEST] <durandal_1707> Fur: ffmpeg does multithreaded decoding
[17:32:55 CEST] <durandal_1707> Fyr ^
[17:33:17 CEST] <Fyr> cool
[17:33:33 CEST] <Fyr> how to use it when converting into FLAC?
[17:33:53 CEST] <durandal_1707> encoding could be simple to add it too
[17:35:05 CEST] <Fyr> great! how do I send a feature request to Xiph?
[17:35:08 CEST] <durandal_1707> I mean multithreaded encoding for audio is not done but should be simple to implement
[17:35:50 CEST] <durandal_1707> I m talking about ffmpeg and not about xiph
[17:36:10 CEST] <Fyr> but does ffmpeg use libflac?
[17:39:05 CEST] <durandal_1707> nope
[17:41:54 CEST] <wk-work> is there any way to make ffmpeg read from disk faster? i'm trying to seek into a 74gb file and it seems to be taking a while
[17:47:31 CEST] <durandal_1707> Faster disk?
[17:51:08 CEST] <Netek> wk-work get a ssd hard drive :)
[17:51:39 CEST] <wk-work> it's not the disk
[17:51:42 CEST] <Netek> its like you are asking can you make a ford fiesta faster :D
[17:51:52 CEST] <Netek> when you want speeds of a ferrari ;)
[17:52:08 CEST] <wk-work> the disk reads as fast as up to 60 mb / s and it's only using 20
[17:52:23 CEST] <Netek> check cpu and ram processes
[17:53:08 CEST] <wk-work> only usiong 20% of one core, ram not an issue
[17:53:09 CEST] <wk-work> i already checked this
[17:53:55 CEST] <Netek> no idea
[17:58:20 CEST] <Nolski> wk-work: are you -ss before -i?
[17:58:34 CEST] <wk-work> Nolski: nope
[17:59:23 CEST] <Nolski> wk-work: you should probably do that. If you seek after -i it is more accurate but much slower
[18:00:52 CEST] <Nolski> wk-work: the first answer here explains it a bit better http://superuser.com/questions/138331/using-ffmpeg-to-cut-up-video
[18:00:53 CEST] <wk-work> Nolski: didn't think about that, thanks, it was *instant* now
[18:01:48 CEST] <Nolski> ;) no problem wk-work
[18:04:48 CEST] <sfan5> wk-work: iirc -ss <where you want to seek> -i input file -ss 0 will seek to the exact time but way faster
[18:06:02 CEST] <c_14> You don't need that second -ss 0
[18:06:12 CEST] <c_14> -ss before -i is accurate by default (in relatively modern versions of ffmpe)
[18:06:14 CEST] <c_14> +g
[18:16:03 CEST] <Netek> ffmpeg -re -i "rtmp://127.0.0.1/itv_effectivestreaming/live live=1" -hls_time 10 -hls_wrap 7 -hls_list_size 3 -f hls itv.m3u8s  when using this command could somebody give me a better understanding what this error means
[18:16:27 CEST] <Netek> Past duration 0.619987 too largeN/A time=00:00:03.04 bitrate=N/A dup=46 drop=0
[18:19:02 CEST] <hardikj> Fyr, you around?
[18:19:13 CEST] <hardikj> seems like OBS use ffmpeg in background?
[18:19:29 CEST] <hardikj> ain't it better to use ffmpeg directly?
[18:21:14 CEST] <Netek> hardikj?
[18:22:24 CEST] <hardikj> Netek, Fyr recommended me to use OBS instead of ffmpeg, since I am using ffmpeg for screen recording of selenium tests using this command 'ffmpeg -framerate 8  -f gdigrab -vcodec libx264 -crf 0  -preset ultrafast output.mkv'
[18:22:33 CEST] <Netek> ahh ok
[18:22:34 CEST] <hardikj> but, this is taking lot of cpu
[18:22:46 CEST] <hardikj> I wanted to reduce the cpu consumption
[18:22:56 CEST] <hardikj> do you have any suggestions?
[18:23:41 CEST] <Netek> hardikj no I am sorry, I am learning ffmpeg myself
[18:23:49 CEST] <hardikj> np
[18:40:40 CEST] <Fyr> hardikj, OBS can use hardware perks.
[18:41:12 CEST] <Fyr> for example, it uses NVENC when grabbing.
[18:41:32 CEST] <Fyr> maybe, it will use ATI's hardware tools to grab.
[18:42:03 CEST] <Fyr> it requires 0% of CPU workload on my computer.
[18:42:11 CEST] <Fyr> it all goes through the videocard.
[18:43:04 CEST] <hardikj> Fyr, notice the tool would be running on virtual machines so no videocard
[18:43:15 CEST] <hardikj> that's why I selected ffmpeg
[18:43:34 CEST] <Fyr> VMs have graphic card too.
[18:45:15 CEST] <Nolski> Hey, I'm trying to split a video using this command http://fpaste.org/232678/43447301/ but I'm getting the error "No such filter: ''"
[18:45:33 CEST] <Nolski> Am I just formatting the filter wrong? It looks okay to me
[18:47:42 CEST] <durandal_1707> pb! Nolski
[18:48:58 CEST] <Nolski> durandal_1707: I did use pastebin?
[18:49:24 CEST] <durandal_1707> but not full output
[18:49:56 CEST] <Nolski> Ah, right
[18:49:58 CEST] <Nolski> http://fpaste.org/232682/47338014/
[18:50:00 CEST] <Nolski> durandal_1707: ^
[18:54:01 CEST] <durandal_1707> hmm, try removing last ;
[18:54:23 CEST] <Nolski> lol wow
[18:54:26 CEST] <Nolski> durandal_1707__
[18:54:29 CEST] <Nolski> durandal_1707++
[18:54:33 CEST] <Nolski> yup
[18:54:36 CEST] <Nolski> good catch
[18:57:34 CEST] <hardikj> Fyr,I just confirmed unfortunately our VM dont :(
[18:57:48 CEST] <hardikj> so i guess only option is to recompile ffmpeg
[18:57:53 CEST] <Fyr> ok
[19:10:13 CEST] <Nolski> Has anyone had issues with running ffmpeg commands through the python subprocess module?
[19:11:21 CEST] <Nolski> I'm getting an error for a command that works when manually run in bash but not python subprocess.call()
[19:11:22 CEST] <Nolski> http://fpaste.org/232690/47420414/
[19:25:39 CEST] <jcay> Nolski escape ' with \' maybe?
[19:28:00 CEST] <chungy> don't have the ' in Python's subprocess call at all
[19:28:06 CEST] <chungy> you don't need to do shell escaping in it
[19:33:16 CEST] <Bombo> i got a video.mp4 with metadata 90 (it's rotated) so i recoded it with -vf rotate=90 but the result looks like 45°...
[19:33:26 CEST] <Bombo> and the metadata ist still there...
[19:34:14 CEST] <Nolski> ahh that's right
[19:34:15 CEST] <pzich> use transpose instead?
[19:34:22 CEST] <Nolski> thanks chungy and jcay
[19:35:32 CEST] <pzich> you may also need to strip the rotation metadata off after actually rotating it with something like -metadata:s:v:0 rotate=0
[19:39:29 CEST] <Bombo> pzich: ok that worked, thx :)
[19:39:39 CEST] <Bombo> but, the creation_time is stripped too
[19:40:02 CEST] <Bombo> can i keep that?
[19:44:21 CEST] <hardikj> Fyr, sorry for the ping, but is there any other way instead of hardware accelaration to improve cpu usage?
[19:46:05 CEST] <Fyr> recompilation with optimization options, required for your CPU.
[19:46:27 CEST] <pzich> Bombo: not sure, you may be able to set it with the metadata flag, but I think it's intentionally set to the time you created the encode
[19:47:23 CEST] <Bombo> got it: metadata:s:v:0 rotate=0 -map_metadata 0:s:0
[19:47:24 CEST] <Bombo> ;)
[19:50:08 CEST] <Fyr> hardikj, if there is no option available, you can try other converters. for example, Handbrake.
[19:50:25 CEST] <Fyr> maybe, it will use the hardware acceleration you need.
[19:50:53 CEST] <hardikj> Fyr, ok, thanks once again :)
[19:51:43 CEST] <Bombo> hmmm now it would be cool if i could say 'just rotate or transpose video if there is a rotate tag in metadata'
[19:52:16 CEST] <Bombo> i guess i'll have to find that out before encoding, with bash magic
[19:57:45 CEST] <c_14> Bombo: git ffmpeg should do that automagically
[20:04:05 CEST] <Bombo> c_14: hmmm it keeps the Metadata: rotate          : 90 and adds Side data:displaymatrix: rotation of -90.00 degrees
[20:04:43 CEST] <Bombo> keeps the "Metadata: rotate          : 90" adds "Side data:displaymatrix: rotation of -90.00 degrees"
[20:05:11 CEST] <Bombo> old mplayer doesn't seem to read the side data
[20:05:18 CEST] <Bombo> mpv does
[20:05:49 CEST] <Bombo> vlc does too
[20:06:50 CEST] <Bombo> so ffmpeg doesn't 'unrotate' but it sets just another tag for players to unrotate at display
[20:07:41 CEST] <c_14> What build did you try?
[20:07:54 CEST] <c_14> (From when)?
[20:08:34 CEST] <c_14> According to a1acae0409700e1abe62cbc900321fcffc9d971d at least, the metadata should be removed when autorotated.
[20:09:27 CEST] <Bombo> ffmpeg version git-2015-04-06-f79cd98
[20:10:07 CEST] <c_14> That's too old.
[20:10:25 CEST] <Bombo> ok ;)
[20:32:57 CEST] <Nolski> Hey all, sorry for asking so many questions. I'm trying to render some text over a video but only during a specific time. I figured if I seek to that spot and then render the text it would work fine but it looks like this command (http://fpaste.org/232725/47940214/) still just renders the text over the whole video
[20:33:19 CEST] <c_14> just use the enable option to the drawtext filter
[20:36:24 CEST] <c_14> If it's not listed in the docs with the filter, it's somewhere at the bottom because it's a general option that applies for several filters.
[20:39:21 CEST] <Nolski> I don't see any enable option listed on the page (even not under drawtext). There are 66 occurances of the word "enable" though so I might just be missing it...
[20:40:00 CEST] <Nolski> found it
[20:40:23 CEST] <Nolski> is there docs on how the option works?
[20:40:34 CEST] <Nolski> s/is/are/
[20:41:06 CEST] <c_14> https://ffmpeg.org/ffmpeg-filters.html#Timeline-editing
[20:41:09 CEST] <c_14> That was it.
[20:41:35 CEST] <c_14> All the ifs/gts etc are documented in ffmpeg-utils
[20:45:08 CEST] <Nolski> awesome
[20:45:24 CEST] <Nolski> Thanks c_14
[20:51:46 CEST] <Bombo> c_14: ack, ffmpeg version git-2015-06-16-20657e0 ;)
[20:52:24 CEST] <Bombo> it simply autorotates it, with no parameters... and metadata is gone
[20:53:36 CEST] <c_14> just like magic
[20:53:44 CEST] <Bombo> (and with just -map_metadata 0:s:0 the creation_time survives too)
[21:09:48 CEST] <spectromas> can anyone tell me what the problem is here? https://bpaste.net/show/fe7df1b84aa7
[21:26:36 CEST] <Bombo> spectromas: what version of ffmpeg do you use? (update it!) ;)
[21:28:22 CEST] <spectromas> Bombo: I have 2.7, that's the current version isn't it?
[21:28:43 CEST] <spectromas> maybe I'm missing a useflag?
[21:28:57 CEST] <podman> if i include yadif=0:-1:0 as a filter, will it always try to deinterlace or will it detect if the source is interlaced and only deinterlace if it is?
[21:31:21 CEST] <Bombo> spectromas: quite so, i just compiled the git version...
[21:36:01 CEST] <spectromas> oh oops I think I was trying to save somewhere without permission
[21:36:10 CEST] <spectromas> what a fool
[21:38:49 CEST] <Bombo> hehe shit happens, and a bad error message
[21:39:34 CEST] <Bombo> i found my xgrab script: ffmpeg -f x11grab -s ${size} -r 30 -i :0.0${area} -sameq -crf 0 -profile:v ultrafast -f alsa -i pulse -acodec pcm_s16le output.mkv
[21:39:47 CEST] <Bombo> worked with a old version
[21:40:09 CEST] <Bombo> -profile:v doesnt...
[21:40:16 CEST] <Bombo> Option profile:v (set profile) cannot be applied to input file pulse -- you are trying to apply an input option to an output file or vice versa. Move this option before the file it belongs to.
[21:41:40 CEST] <spectromas> that looks handy. I do this so seldom that I forget every time
[21:43:28 CEST] <Bombo> Option profile:v (set profile) cannot be applied to input file pulse
[21:43:37 CEST] <Bombo> crap orders
[21:49:18 CEST] <Bombo> ffmpeg -y -f x11grab -i :0.0${area} -f alsa -i pulse -c:v libx264 -crf 0 -profile:v ultrafast -r 30 -vf scale=${size} -c:a pcm_s16le out.mkv
[21:49:23 CEST] <Bombo> almost got it ;)
[21:49:35 CEST] <Bombo> Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height
[21:56:04 CEST] <voip_> hello guys
[21:56:58 CEST] <voip_> may i use rasberi pi board for h264 live stream transcodig ?
[21:58:36 CEST] <luckcolors> hello
[21:58:42 CEST] <Fyr> hey
[21:58:57 CEST] <luckcolors> can someone help me?
[21:59:39 CEST] <Fyr> it depends..
[22:00:33 CEST] <luckcolors> i'm using ffmpeg to download and save an m3u8 playlist
[22:00:57 CEST] <luckcolors> but ffmpeg save the download in a mp4 file
[22:01:27 CEST] <luckcolors> is it possible to just download the single .ts files of the playlist?
[22:01:48 CEST] <luckcolors> and not join them in a mp4 file
[22:02:27 CEST] <Fyr> that m3u8 file on pastebin + the command you are using.
[22:02:41 CEST] <luckcolors> a sec
[22:03:05 CEST] <Bombo> spectromas: http://bombo.jpe.gs/xgrab.sh ;)
[22:04:51 CEST] <Bombo> does work now with git version, just one minor issue 'Guessed Channel Layout for  Input Stream #1.0 : stereo' although i included '-ac 2' ...
[22:05:45 CEST] <Bombo> voip_: it's probably too slow, as encoding is done in cpu, maybe Pi2 or a mod with faster cpu
[22:07:24 CEST] <voip_> Bombo, yes i menat Pi2 model with faster CPU, so did you tryffmpeg on rasbery ?
[22:07:48 CEST] <spectromas> thanks a lot Bombo :)
[22:08:35 CEST] <luckcolors> fyr here's the truncated version of the file http://pastebin.com/uuuiBpmR
[22:09:19 CEST] <luckcolors> i don't know the command with i start ffmpeg because i'm using youtube-dl
[22:09:36 CEST] <Bombo> voip_: no i got Pi1, definitely too slow i didn't even try ;)
[22:09:50 CEST] <Fyr> youtube-dl automatically uses ffmpeg to compund the files.
[22:09:55 CEST] <voip_> Bombo, :)
[22:10:06 CEST] <Bombo> spectromas: np
[22:10:08 CEST] <Fyr> luckcolors, what command do you use with youtube-dl?
[22:10:43 CEST] <luckcolors> youtube-dl http://www.twitch.tv/twitch
[22:10:51 CEST] <luckcolors> no wait
[22:11:56 CEST] <luckcolors> youtube-dl http://www.twitch.tv/twitch/v/6244102
[22:12:03 CEST] <luckcolors> this is the command i use
[22:12:10 CEST] <Bombo> yes let's dl the internet ;)
[22:12:57 CEST] <luckcolors> yeah :)
[22:13:05 CEST] <Fyr> luckcolors, youtube-dl is downloading mp4 file.
[22:13:22 CEST] <Bombo> isn't twitch live streaming?
[22:13:23 CEST] <Fyr> it's the problem of youtube-dl and its parameters, not ffmpeg.
[22:14:09 CEST] <luckcolors> youtube-dl just gets the stream metadata (output file name + m3u8 url) and the passes the execution to ffmpeg
[22:15:09 CEST] <luckcolors> infact i cannot even download without ffmpeg
[22:16:17 CEST] <luckcolors> fyr which parameters i can  give to ffmpeg so it cdan download just the .ts files?
[22:16:34 CEST] <Bombo> luckcolors: but yt-dl sets parameters for ffmpeg
[22:17:05 CEST] <Fyr> luckcolors, http://pastebin.com/TubuZe4z
[22:17:26 CEST] <Fyr> youtube-dl offers only m4a.
[22:18:57 CEST] <Bombo> maybe twitch does only offer m4a
[22:19:03 CEST] <luckcolors> http://vod.ak.hls.ttvnw.net/v1/AUTH_system/vods_e869/twitch_14883844112_257836691/chunked/index-0000000014-dikz.ts?start_offset=0&end_offset=963311
[22:19:16 CEST] <Fyr> I see.
[22:19:28 CEST] <Fyr> but youtube-dl can see only mp4 files.
[22:19:35 CEST] <Fyr> ask, #youtube-dl
[22:19:54 CEST] <luckcolors> ok
[22:22:41 CEST] <luckcolors> can someone remove the twitch link that i posted from the logs? :P
[22:23:02 CEST] <Fyr> easily
[22:23:10 CEST] <Fyr> call KGB, they will do the trick.
[22:23:15 CEST] <luckcolors> thanks
[22:30:16 CEST] <luckcolors> thanks fyr for your help bye
[22:30:21 CEST] <Fyr> ok
[23:22:05 CEST] <dine909> hi there - i'm looking for some advice, i need to make a video (of undetermined length) crossfade into itself over 5 seconds at the end (for looped playback), i've been trying with -filter_complex using an example of something similar i found, but i'm under pressure and the syntax is making me sick, is there an easier way to achieve the same result?
[23:24:04 CEST] <durandal_1707> what filters you used
[23:26:16 CEST] <dine909> http://hastebin.com/xinulesaxa.sh so far
[23:27:02 CEST] <dine909> but thats totally wrong
[23:28:01 CEST] <dine909> i just changed an example i found to use the same file in 2 streams, i know it can work i just cant find the right brain door to set the correct length and fade points relatively using PTS
[23:30:46 CEST] <dine909> for reference, that example came from http://superuser.com/questions/778762/crossfade-between-2-videos-using-ffmpeg
[23:34:26 CEST] <dine909> what does fade=t=out mean ? what is t?
[23:35:08 CEST] <Nolski> dine909: normally when I see t it means to specifiy the input in seconds
[23:35:17 CEST] <Nolski> (I may be wrong though)
[23:35:48 CEST] <Nolski> dine909: https://ffmpeg.org/ffmpeg-filters.html#fade
[23:35:55 CEST] <Nolski> It means type
[23:36:24 CEST] <dine909> ah i see, thanks
[23:36:33 CEST] <Nolski> np
[23:37:12 CEST] <dine909> so fade=t=out:st=4:d=1:alpha=1
[23:37:25 CEST] <dine909> is a fadeout at 4s lasting 1s?
[23:37:58 CEST] <Nolski> dine909: yup, I think so
[23:38:18 CEST] <Nolski> It'd fade to black
[23:39:38 CEST] <dine909> now, how could i set st to be length-5s
[23:39:54 CEST] <Nolski> dine909: you want the duration of the fade to be 5 seconds?
[23:40:00 CEST] <Nolski> you just set d=5
[23:40:18 CEST] <dine909> yes, but 5s before the end of the clip
[23:40:25 CEST] <dine909> given i don't know how long that might be
[23:40:42 CEST] <Nolski> dine909: you find out how long the clip is and then you subtract 5 seconds from that
[23:40:46 CEST] <dine909> ie, fade any input to black at the end
[23:40:47 CEST] <dine909> yes
[23:41:02 CEST] <Nolski> It'd be a step separate from the fade
[23:41:09 CEST] <dine909> thats  my question is ENDPTS a thing?
[23:42:15 CEST] <Nolski> not sure
[23:47:43 CEST] <Nolski> Is it possible to loop a section of a video?
[00:00:00 CEST] --- Wed Jun 17 2015


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