[Ffmpeg-devel-irc] ffmpeg.log.20171230

burek burek021 at gmail.com
Sun Dec 31 03:05:01 EET 2017


[00:19:43 CET] <Afdal> guh, can someone tell me all the ffmpeg hotkeys
[00:19:52 CET] <Afdal> I bumped something and froze a 4-hour encode in the middle
[00:19:56 CET] <Afdal> How do I start this up again
[00:20:14 CET] <Afdal> continue, rather
[00:20:20 CET] <Afdal> seems like the encode is paused
[00:20:32 CET] <c_14> froze?
[00:20:40 CET] <c_14> ^Z or ^S by any chance?
[00:21:28 CET] <Afdal> no it wasn't the BASH process halt ctrl+Z thingy
[00:21:42 CET] <Afdal> the process is still running, it just isn't doing anything :/
[00:21:52 CET] <c_14> is it still using cpu?
[00:22:09 CET] <Afdal> mmm
[00:22:10 CET] <Afdal> yes
[00:22:22 CET] <Afdal> 80% CPU, apparently
[00:22:38 CET] <Afdal> oh perhaps I just turns off the output???
[00:22:45 CET] <Afdal> How do I turn that back on
[00:22:50 CET] <c_14> press +
[00:23:07 CET] <c_14> + and - control the verbosity levels
[00:23:12 CET] <c_14> if you press - once the status stops updating
[00:23:26 CET] <Afdal> mmhmm
[00:23:31 CET] <Afdal> well that's probably what I did
[00:23:39 CET] <Afdal> unfortunately, something else seems to be wrong as well now
[00:23:47 CET] <c_14> "something else"?
[00:23:53 CET] <furq> Afdal: http://vpaste.net/mE2Gf
[00:23:55 CET] <Afdal> Press + or = or anything else just inputs characters
[00:24:06 CET] <furq> you need to hit enter as well
[00:24:13 CET] <c_14> maybe you hit c/C?
[00:25:21 CET] <furq> at least on windows you need to hit enter
[00:25:35 CET] <Afdal> https://gyazo.com/fd2ef05fe4f098f30cd0f2be900be77b
[00:25:37 CET] <Afdal> nooooo
[00:25:41 CET] <Afdal> now it stopped completely
[00:25:52 CET] <Afdal> Gotta start this whole encode over again ;_;
[00:26:08 CET] <furq> crf 1 isn't lossless
[00:26:32 CET] <furq> also preset placebo is exactly as much of a waste of time as the name implies
[00:26:41 CET] <Afdal> hehe
[00:26:59 CET] <Afdal> oh crap you're right
[00:27:04 CET] <Afdal> crf 0 is the lossless one
[00:27:10 CET] <Afdal> Can't believe I forgot that
[00:27:14 CET] <c_14> you want -qp 0 in any case
[00:27:16 CET] <furq> good job you cancelled that encode then
[00:27:21 CET] <Afdal> lol
[00:27:30 CET] <Afdal> sheesh
[00:27:31 CET] <furq> but yeah don't use placebo
[00:27:36 CET] <Afdal> I like using placebo
[00:27:36 CET] <furq> veryslow is fine
[00:27:43 CET] <Afdal> for archiving
[00:28:02 CET] <Afdal> I've done some comparisons before and it saves a smidge of filesize compared to ultraslow
[00:28:12 CET] <Afdal> especially with low-color 2D animation
[00:28:14 CET] <furq> it's really not worth the cpu time for the half a percent you'll save
[00:28:27 CET] <therage3> For archiving I just use the original source material, honestly
[00:28:50 CET] <furq> well i assume the input is rawvideo and this is a lossless copy so that's all fine
[00:28:51 CET] <Afdal> original source is ffv1 4 times as large or raw AVI like 10 times larger
[00:28:55 CET] <Afdal> I need muh space
[00:29:13 CET] <therage3> O.O
[00:29:40 CET] <furq> i'm guessing this isn't ikaruga the overrated dreamcast shooting game then
[00:30:33 CET] <Afdal> uh
[00:30:35 CET] <Afdal> lol
[00:30:37 CET] <Afdal> it is actually
[00:30:50 CET] <Afdal> placebo wouldn't have helped me all that much with this since it's a 3D game
[00:30:53 CET] <furq> i'm surprised x264 does that much better than ffv1
[00:30:57 CET] <Afdal> but I like doing it anyway :)
[00:31:10 CET] <Afdal> Yeah x264 lossless is hugely better than ffv1 for archiving
[00:31:37 CET] <Afdal> The main use for ffv1 that I can see is low cpu usage for streaming from another source when cpu usage is really imporant to you
[00:31:49 CET] <Afdal> but there's always raw video for that too
[00:31:55 CET] <furq> nah ffv1 is pretty good
[00:32:03 CET] <furq> and it's slower than x264 ultrafast in my experience
[00:32:18 CET] <Afdal> What is it "pretty good" for @_@
[00:32:18 CET] <furq> if you want low cpu usage then huffyuv/ffvhuff/utvideo are much better
[00:33:00 CET] <Afdal> I've been trying to understand the niche for ffv1 for a while now and I just don't get it
[00:33:02 CET] <furq> ffv1 compresses pretty well
[00:33:25 CET] <furq> certainly not as well as an inter codec for animation though
[00:33:37 CET] <furq> but i've seen it do about as well as x264 medium
[00:33:45 CET] <Afdal> I've done some tests with lossless vp8/vp9 and x264/x265 and they all do way better than ffv1
[00:33:58 CET] <furq> ffv1 is intra-only so it depends a lot on the source
[00:33:59 CET] <Afdal> a third the file size of ffv1 or better
[00:34:05 CET] <Afdal> hmm
[00:34:08 CET] <Afdal> I see
[00:34:17 CET] <furq> it's much better than any other intra-only codec i've seen though
[00:34:28 CET] <Afdal> So it might be better for film archival than the other codecs then?
[00:34:39 CET] <furq> potentially
[00:34:47 CET] <Afdal> Also yeah Ikaruga is pretty overrated
[00:35:07 CET] <Afdal> I finally single-credit cleared it so I can articulate just what I don't like about it now :)
[00:35:15 CET] <furq> i mean it's fine but it's no garegga
[00:35:28 CET] <furq> but then what is
[00:35:29 CET] <Afdal> tru dat
[00:35:33 CET] <Afdal> and Garegga is no Batrider
[00:35:40 CET] <furq> batrider is pretty great
[00:36:13 CET] <Afdal> Am I speaking to a Raizing fan
[00:36:17 CET] <furq> you sure are
[00:36:20 CET] <Afdal> oh boy
[00:36:23 CET] <Afdal> you got taste fam
[00:36:30 CET] <Afdal> Dimahoo > Ikaruga
[00:36:43 CET] <furq> dimahoo is a confusing mess and i love it
[00:39:11 CET] <therage3> "and i love it"
[00:39:20 CET] <therage3> not what usually follows after "is a confusing mess"
[00:39:41 CET] <furq> it's good in spite of that really
[00:39:57 CET] <Afdal> Honestly my only main complaint with Dimahoo is the really obtuse method for displaying your treasure listings
[00:40:19 CET] <Afdal> I'd say fumbling with that has probably resulted in about a third of my deaths
[00:40:54 CET] <furq> i tended to just ignore the treasure completely whenever i played it
[00:41:01 CET] <Afdal> oh man
[00:41:03 CET] <furq> memorising all of that is not my idea of fun
[00:41:08 CET] <Afdal> I wish I could do that
[00:41:09 CET] <Afdal> I really do
[00:41:16 CET] <Afdal> I'd have beaten Dimahoo a long time ago
[00:41:16 CET] <furq> i never got into it that much really
[00:41:29 CET] <Afdal> but I find it impossible to ignoring treasure collecting anymore
[00:41:37 CET] <furq> but at the end of the stage it says "GREAT BONUS" and that alone makes it a good game
[00:41:44 CET] <Afdal> I'm so close to collecting them all in a single playthrough
[00:42:06 CET] <furq> i should really get back into shooting games
[00:42:36 CET] <Afdal> Still... I did a small experiment encoding Ikaruga earlier and compared file sizes of x264 to ffv1 and was getting 1/4 the file size
[00:42:49 CET] <Afdal> however that was with crf 1 when I forgot that wasn't lossless
[00:43:10 CET] <furq> yeah 0 will be quite a bit bigger iirc
[00:43:42 CET] <Afdal> that's a 3D game with lots of perspective and shading, so it doesn't benefit from inter-frame compression in quite the same way that 2D game videos do
[00:44:50 CET] <Afdal> real glad I popped in here, it took me all day just to dump the raw source for this
[00:44:57 CET] <Afdal> was going to delete it once I had it compressed
[00:45:01 CET] <Afdal> thinking it was lossless -_-
[00:46:30 CET] <Afdal> okay I'm at 1min30sec and this is already 500MB
[00:46:40 CET] <Afdal> maybe this isn't worth archiving in x264
[00:52:03 CET] <spiderkeys> I'm having a bit of an issue muxing elementary h264 to mp4 using the newer releases (3.2+). Many of the fields and methods for working with AVStreams and the codec contexts are now deprecated and I can't really find any examples or guidance for how to properly copy codec context information from an input stream to an output stream. I'm using a custom UDP based input stream, so I create a custom avio context for the input, probe it
[00:53:45 CET] <spiderkeys> Then my next step is to create the output format context (mp4), and add a new stream which copies the codec and picture information from the input stream. However, avcodec_copy_context is now deprecated and says to use avcodec_parameters_from/to_context, but I am not sure how exactly to use them with relation to an existing input stream. Anyone have some guidance they can share?
[00:54:04 CET] <spiderkeys> I can share my code if it helps.
[03:31:53 CET] <Afdal> Woo finished.  ffv1 size: 20.6 GB, x264 lossless size: 12.7 GB
[03:32:08 CET] <Afdal> okay lol, was expecting something much smaller than that
[03:32:31 CET] <Afdal> I ain't archiving no 12.7 GB video file
[04:13:12 CET] <meriipu> ffmpeg -i in.mkv -r 5 -filter_complex "split[out0][out1]" -map "[out0]" out0.mkv -map "[out1]" out1.mkv # why does out0.mkv have a framerate of 5fps while out1.mkv retains the original input file framerate?
[04:15:19 CET] <DHE> because "-r 5" is part of the output0.mkv options while -filter_complex is not specific to anything and is a global option
[04:15:34 CET] <DHE> also note that you can specify "-map 0:v" on each output instead and not use the split filter
[04:16:18 CET] <meriipu> I was planning to use a different filter on each file afterwards though.  But if the -r is part of the first output then it makes a lot more sense
[04:16:25 CET] <meriipu> thanks
[04:16:56 CET] <meriipu> or well on each stream
[04:17:02 CET] <DHE> unless you need to do some pre-processing on the input that's shared, I might just do:  ffmpeg -i in.mkv -vf filterchain1 -map 0:v out0.mkv -vf filterchain2 -map 0:v out1.mkv
[04:20:02 CET] <meriipu> that does look quiet a bit cleaner
[04:39:10 CET] <Afdal> What are all the container formats that ffmpeg can pipe from nicely?
[04:39:23 CET] <Afdal>  (since some containers like to stick important info at the end of the file)
[04:43:34 CET] <klaxa> mkv can be streamed
[04:43:41 CET] <klaxa> i would think nut is good as well
[04:44:25 CET] <Afdal> AVI has worked in my experience, despite people claiming that AVI leaves its junk at the end of the file
[04:44:32 CET] <spiderkeys> do most media players support fragmented mp4 these days?
[04:45:10 CET] <spiderkeys> that would support streaming as well
[04:45:52 CET] <klaxa> yes, but for piping it into ffmpeg you need some flags
[04:50:41 CET] <DHE> I think the video being piped in needs to be prep'd accordingly
[04:51:00 CET] <DHE> mpegts is broadcast standard streamable
[04:52:48 CET] <Afdal> yeah transport streams are the obvious choice
[04:52:51 CET] <Afdal> when you have the choice
[07:15:32 CET] <M6HZ> Hello, is there a way to control ffplay [While playing] shortcuts in `man ffplay` via the stdin of a term instead of a X11 window ?
[07:24:01 CET] <buu> nope!
[07:24:12 CET] <buu> I just checked =[
[07:57:15 CET] <M6HZ> buu, Ok thank you. That's sade, it means that we need a window even to play audio files ...
[07:58:58 CET] <buu> yeah =[
[08:00:27 CET] <M6HZ> Also, is there a way to reduce the lag between two `ts` segments of a `m3u8` stream using ffplay?
[08:01:47 CET] <buu> how much lag is there?
[08:04:50 CET] <M6HZ> Not that much, maybe less than 2sec at worst, but it's not as 'smooth' as what mpv can do.
[08:09:43 CET] <buu> hmm
[08:09:45 CET] <buu> I wonder what's going on
[08:09:50 CET] <buu> maybe restablishing the connection
[09:03:32 CET] <binaryTr1> I'm trying to save filename as epochtime.mp4 but it's getting saved as %s.mp4. What's the issue ? ffmpeg  -video_size 1920x1080 -framerate 25 -f x11grab -i :0.0+0,0 -f pulse -ac 2 -i default  -strftime 1 "%s.mp4"
[09:16:53 CET] <buu> I'm guessing %s isn't a valid escape
[17:18:17 CET] <pos> so, i've got these rtsp sources which, when using ffmpeg with -vcodec copy, end up with funky files. let's say i've captured 15 seconds of video, i get a video file sized about 5MB but all players think it's 50 minutes long
[17:18:25 CET] <pos> mplayer/mpv complain about invalid timestamps, vlc crashes
[17:18:31 CET] <pos> i've tried -fflags +gentps and -vsync drop to no avail
[17:19:09 CET] <pos> just streaming work in either player ofc
[20:15:03 CET] <Johnjay> mplayer huh
[20:15:16 CET] <Johnjay> do you think mplayer would have the ability to resume playback of a playlist after closing?
[20:15:24 CET] <Johnjay> vlc apparently does not
[21:44:50 CET] <Kuroonehalf> Hi. I would like some help in composing this command please. My goal is to take a set of frames in PNG and turn them into a video with a watermark. I am able to do each step separately, with "ffmpeg -y -r 1 -i to_use/%01d.png -vf scale=-1:800 video.mp4" and then "ffmpeg -y -i video.mp4 -i watermark.png -filter_complex 'overlay=x=main_w-84:y=main_h-18' video_watermarked.mp4", but I am trying to optimize this all into a
[21:44:50 CET] <Kuroonehalf> single command, and having trouble figuring out how to do that
[21:48:09 CET] <sfan5> ffmpeg -y -r 1 -i to_use/%01d.png -filter_complex 'scale=-1:800 [a]; movie=watermark.png [b]; [a][b] overlay=x=main_w-84:y=main_h-18' video_watermarked.mp4
[21:48:14 CET] <Johnjay> furq is the vlc codebase clean enough to contribute to?
[21:48:33 CET] <Johnjay> i'm thinking of submitting a patch that automatically resumes a playlist at user request
[21:57:18 CET] <Kuroonehalf> @sfan5 thank you, that works great!
[23:58:41 CET] <bray90820_> OFF TOPIC: to have something be 1080p with a different aspect ratio would you make the hight 1080?
[00:00:00 CET] --- Sun Dec 31 2017


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