[Ffmpeg-devel-irc] ffmpeg.log.20170818

burek burek021 at gmail.com
Sat Aug 19 03:05:01 EEST 2017


[01:25:32 CEST] <jonascj> I have an mp4 file which originally plays in the expected orientation (people appear upright on computer monitor), but when transcoded to ts the video appears flipped or rotated 180deg. Anyone experienced something similar and have suggestions for a workaround/fix?
[01:33:48 CEST] <iive> jonascj: i've heard that mp4 has some matrix that allow manipulation of the decoded image. e.g. having additional cropping
[01:34:26 CEST] <iive> it might also allow rotation.
[01:35:09 CEST] <iive> so my first guess is that the source video is flipped and has data to correct the flip. but ffmpeg losses that info.
[01:36:06 CEST] <iive> i'm actually sure there is a filter that could flip the image, or rotate it on 90 degree intervals.
[01:50:40 CEST] <voip_> Hello guys
[01:51:02 CEST] <voip_> I have segmentation fault error with qsv codec
[01:51:04 CEST] <voip_> https://pastebin.com/P7gnqdBT
[01:51:56 CEST] <c_14> You either didn't build it correctly or didn't link it correctly
[01:54:22 CEST] <c_14> Or didn't patch your kernel
[01:55:12 CEST] <voip_> c_14, i didnt get any error during build . kernel 3.10.0-327.el7
[01:55:25 CEST] <voip_> ok thank you i will try again
[01:55:58 CEST] <c_14> did you use the media codec patches to build the kernel?
[01:56:08 CEST] <c_14> Are you using the media codec patched versions of the libraries?
[01:57:32 CEST] <voip_> as i know last version od IntelSDK doesnt require patches
[01:58:38 CEST] <c_14> last time I built it it needed them
[01:58:45 CEST] <c_14> was march/april afair
[02:03:48 CEST] <voip_> FFmpeg
[02:03:48 CEST] <voip_> -
[02:03:48 CEST] <voip_> y
[02:03:48 CEST] <voip_> 
[02:03:48 CEST] <voip_> i test.mp4
[02:03:49 CEST] <voip_> -
[02:03:53 CEST] <voip_> vcodec h264 _ qsv
[02:03:55 CEST] <voip_> -
[02:03:57 CEST] <voip_> acodec copy
[02:03:59 CEST] <voip_> -
[02:04:01 CEST] <voip_> b:v 8000K out.mp4 passing
[02:39:11 CEST] <sh4rm4^bnc> how do i specify to reencode to stereo rather than 5.1 ?
[02:39:32 CEST] <relaxed> -ac 2
[02:42:03 CEST] <sh4rm4^bnc> thanks!
[03:30:10 CEST] <Aerroon> question: if i have a video file that i run in a video player like VLC
[03:30:22 CEST] <Aerroon> if i then run the same video file again will i see identical frames?
[03:30:56 CEST] <Aerroon> or are they "close enough"?
[03:34:18 CEST] <relaxed> you mean playing it back a second time?
[03:35:03 CEST] <relaxed> after transcoding it?
[05:16:26 CEST] <Aerroon> relaxed, no, if i play it back on two separate occasions
[05:16:30 CEST] <Aerroon> will i get the exact same frames
[05:51:39 CEST] <Videogamer555> Need some help with muxer RTP_MPEGTS
[05:55:16 CEST] <Videogamer555_> Can anybody here see my posts?
[05:55:34 CEST] <Videogamer555_> Just curious because the last time I posted it didn't appear on my own screen.
[10:56:06 CEST] <Ingvix> just checking that if I had accidently run a bad command resulting an empty file which overwrote the original, there's no way to get the original back?
[10:57:30 CEST] <klaxa> maybe with file recovery tools
[10:57:59 CEST] <klaxa> data is usually not immediatly overwritten with 0s
[10:58:07 CEST] <klaxa> if overwritten or deleted
[11:10:23 CEST] <kerio> Aerroon: most codecs have a deterministic output
[11:10:52 CEST] <kerio> and even if they didn't, i'd expect the same player to play the same video file in the same way all the times
[11:18:05 CEST] <Aerroon> kerio, thank you
[12:55:06 CEST] <paveldimow> Hi, how can I preserve metadata from video stream in mp4? For example, I have https://pastebin.com/ck6J0Jtq the problem is that since ffmpeg does not support amf0 I want to remove it since because of that I don't get the right duration of video: Duration: 93:13:29.07, start: 0.000000, bitrate: 0 kb/s
[14:03:37 CEST] <berz3rk> hello guys
[14:04:19 CEST] <berz3rk> I have a bunch of 3d movies in mkv format and have different needs to convert them all in a big loop to mp4 files with only using first audio stream, limiting audio bitrate to 320 kb/s and using audio codec aac. Can you help me how to achieve this? thanks
[14:04:48 CEST] <berz3rk> something like this :/ ffmpeg -i *.mp4 -c:v copy -c:a aac -b:a 320k MyMovieNameXX_3dff_sbs.mp4
[14:16:59 CEST] <redrabbit> today i got why HEVC is far from beeing widely used
[14:17:27 CEST] <redrabbit> on my cellphone cpu usage was near maxed out with not even extravagant bitrates
[14:17:31 CEST] <redrabbit> battery killer
[14:17:55 CEST] <redrabbit> AVC on the other hand have super low ressource use
[14:18:05 CEST] <redrabbit> hw decoders working
[14:18:19 CEST] <ketas> need hw for hevc
[14:18:22 CEST] <ketas> :P
[14:18:31 CEST] <redrabbit> maybe the phone have hw decoders for hevc but the software dont know how to use it
[14:18:41 CEST] <redrabbit> or maybe its because its an old phone ^^
[14:20:01 CEST] <redrabbit> (vlc)
[14:21:54 CEST] <redrabbit> phone is over 5 years old
[14:22:01 CEST] <redrabbit> still working solid imo
[14:22:48 CEST] <redrabbit> Qualcomm MSM8260A Snapdragon S4 Plus
[14:23:44 CEST] <redrabbit> http://www.gsmarena.com/acer_cloudmobile_s500-4542.php
[14:42:26 CEST] <Mavrik> Yeah, 5 year phone won't have a HEVC decoder
[15:25:18 CEST] <redrabbit> that would be a sort of good reason to upgrade
[15:28:42 CEST] <klaxa> eeh, there isn't that much hevc content available yet
[15:53:16 CEST] <redrabbit> yeah
[15:53:36 CEST] <redrabbit> i can use the hardware encoders of my nvidia card to stream HEVC though
[15:54:51 CEST] <redrabbit> i have setup an IPTV service so i can access terrestrial / satellite tv when i'm not home
[16:23:18 CEST] <alexpigment> redrabbit: do you have a cablecard-type setup, or do you use a capture card?
[16:23:35 CEST] <alexpigment> or hdhomerun
[16:26:06 CEST] <redrabbit> two usb tuners for the terrestrial (dvb-t2) and pci-E card with two dvb-s2 tuners
[16:26:14 CEST] <redrabbit> + dvbviewer for software
[16:26:39 CEST] <alexpigment> ah gotcha
[16:26:47 CEST] <redrabbit> works neat
[16:27:03 CEST] <alexpigment> i've got two tuners for OTA, but here all the cable is encrypted
[16:27:04 CEST] <redrabbit> i spent about 2 days neatpicking my transcoding presets
[16:27:15 CEST] <alexpigment> does HEVC really help that much?
[16:27:24 CEST] <redrabbit> oh yeah, cable is impossible to to break without the keys
[16:27:29 CEST] <redrabbit> you need a card
[16:27:51 CEST] <redrabbit> i heard it was possible for virgin somewhere
[16:27:52 CEST] <alexpigment> yeah, i've got Hauppauge capture cards, but I haven't figured out how to get the channels to change remotely yet
[16:28:01 CEST] <redrabbit> im dont use that isp though
[16:28:12 CEST] <redrabbit> i get all my stuff from the satellite
[16:28:17 CEST] <alexpigment> america is full of cable monopolies
[16:28:25 CEST] <alexpigment> and I can't get satellite due to condo rules
[16:28:27 CEST] <redrabbit> got like 7000 channels with my motorized dish
[16:28:43 CEST] <alexpigment> would love to get satellite just for the picture quality
[16:28:54 CEST] <alexpigment> time warner / spectrum cable is not even *trying* on picture quality
[16:28:59 CEST] <redrabbit> meh
[16:29:07 CEST] <redrabbit> yeah there is some nice hd stuff
[16:29:09 CEST] <alexpigment> granted, I think all cable companies are inherently limited in what they can do with quality
[16:29:17 CEST] <redrabbit> lots of stuff is still sd  / mpeg 2
[16:29:21 CEST] <redrabbit> unwatchable
[16:29:31 CEST] <alexpigment> the HD stuff is what I find most unwatchable
[16:29:52 CEST] <redrabbit> well my cable compagny use H.264 and AAC
[16:30:09 CEST] <redrabbit> they broadcast dvb-C and dvb-t2 in the cable
[16:30:17 CEST] <redrabbit> i use the dvb-t2, most of the fta is there
[16:30:19 CEST] <alexpigment> mine uses MPEG-2, but they cram 3-4 channels (or more) into a single 38mbps channel allotment
[16:30:23 CEST] <redrabbit> and quality is similar to sattelite
[16:30:27 CEST] <redrabbit> its great
[16:30:33 CEST] <redrabbit> really depends on encoders
[16:30:35 CEST] <alexpigment> yeah, dvb-t2 should be awesome
[16:30:40 CEST] <redrabbit> dvb-c same
[16:30:50 CEST] <redrabbit> its just a mean of transport
[16:30:59 CEST] <redrabbit> they use shitty codec settings
[16:31:27 CEST] <redrabbit> its like they are doing a contest for dumbest encoder settings
[16:31:29 CEST] <redrabbit> on tv stuff
[16:31:31 CEST] <alexpigment> haha
[16:31:41 CEST] <alexpigment> i promise, whatever dumb settings they use, cable is worse
[16:31:56 CEST] <alexpigment> i wouldn't be surprised if some of the HD channels are under 6mbps MPEG-2
[16:31:59 CEST] <redrabbit> from the moment you see MPEG-2 it can only suck
[16:32:09 CEST] <redrabbit> full hd or 720
[16:32:10 CEST] <alexpigment> not if you use all the bandwidth you're allowed
[16:32:29 CEST] <redrabbit> yeah it needs a ton of bw to look remotely good
[16:32:32 CEST] <alexpigment> if you used one HD channel per 38mbps stream, it would look amazing
[16:32:38 CEST] <redrabbit> 16:27 < alexpigmen> does HEVC really help that much?
[16:32:49 CEST] <redrabbit> if you have the right hardware to decode yeah
[16:32:56 CEST] <kerio> surely you can just get a capture card with a CAM interface
[16:32:59 CEST] <kerio> for pay tv
[16:33:01 CEST] <redrabbit> you get a better picture
[16:33:05 CEST] <kerio> right? D:
[16:33:06 CEST] <alexpigment> CAM interface?
[16:33:22 CEST] <furq> redrabbit: is this the thing you're screen capturing for
[16:33:22 CEST] <redrabbit> especially for low bandwith setups when you have to fit as much as you can in a little package
[16:33:32 CEST] <iive> content access management
[16:33:32 CEST] <furq> i take it you can't just grab the stream with ffmpeg and transcode it
[16:33:36 CEST] <redrabbit> furq: nope, i tried obs just for the luls
[16:33:41 CEST] <furq> oh ok
[16:33:43 CEST] <redrabbit> streamed some gta to youtube
[16:33:49 CEST] <redrabbit> just to see how it would look
[16:33:54 CEST] <alexpigment> kerio: not sure exactly what you're implying, but the source of the content in my area is the problem, not the capturing
[16:34:00 CEST] <redrabbit> its a bit crappy i only have 5mpbs upload
[16:34:05 CEST] <redrabbit> could be worse i guess
[16:34:13 CEST] <furq> that's more than most services will let you stream anyway
[16:34:26 CEST] <kerio> youtube lets you stream as high as you want i think
[16:34:29 CEST] <redrabbit> i dont look at streaming from games much
[16:34:35 CEST] <devinheitmueller> kerio: here in the US we have the CableCard standard, which is basically the US equivalent to CAMs.  However because of DRM you cannot access the decrypted video unless the downstream equipment is protected as well.
[16:34:37 CEST] <alexpigment> redrabbit: i suppose if you're comparing HEVC to H264 via hardware alone, then yes, i'm sure it helps. but I think x264 is more efficient than nvenc HEVC fwiw
[16:34:40 CEST] <redrabbit> i have no reference point for quality
[16:34:42 CEST] <furq> doesn't youtube boot you if your stream bandwidth is too high
[16:34:52 CEST] <furq> i've never tried it but i remember people in here complaining about that
[16:34:59 CEST] <redrabbit> alexpigment: yeah agreed
[16:35:03 CEST] <furq> alexpigment: it is much more efficient
[16:35:09 CEST] <furq> but obviously not so much if you have realtime constraints
[16:35:16 CEST] <kerio> furq: they recommend 20-51mbps for 2160p60 streams
[16:35:22 CEST] <furq> fun
[16:35:25 CEST] <furq> maybe i'm thinking of twitch
[16:35:31 CEST] <kerio> yea twitch boots you if you go over 6mbps
[16:35:34 CEST] <alexpigment> twitch is really low
[16:35:39 CEST] <alexpigment> i think it's like 3-4mbps max
[16:35:45 CEST] <redrabbit> you can get comparable perfs with highest settings on x265 vs the "loose" settings on nvenc
[16:35:46 CEST] <alexpigment> which sucks, but hey, they're not google
[16:35:50 CEST] <furq> it's a good job that video game footage is extremely easy to compress
[16:35:52 CEST] <redrabbit> its real time and cpu free though
[16:35:55 CEST] <furq> especially first-person games
[16:36:09 CEST] <kerio> alexpigment: yea they're not google, they're amazon
[16:36:10 CEST] <kerio> >:(
[16:36:11 CEST] <alexpigment> furq: not always true in my experience
[16:36:21 CEST] <furq> that was some of that classic furq sarcasm
[16:36:29 CEST] <redrabbit> furq: i sent you a link to my stream test
[16:36:31 CEST] <furq> that we all love so much
[16:36:36 CEST] <kerio> alexpigment: i think they relaxed it to 6
[16:36:38 CEST] <redrabbit> just to have an external pov on the quality
[16:36:40 CEST] <alexpigment> kerio: true. i was really talking about the rules that have been in place since before amazon
[16:36:41 CEST] <redrabbit> if you have a minute
[16:36:41 CEST] <kerio> so people can stream 1080p60 kinda decently
[16:37:08 CEST] <redrabbit> i streamed 1440p
[16:37:17 CEST] <redrabbit> figured yt would give more bw
[16:37:46 CEST] <alexpigment> redrabbit: have you ever watched a youtube stream? ;)
[16:37:59 CEST] <redrabbit> not much
[16:38:01 CEST] <alexpigment> "i'll take my low-quality video with a side of macroblocking, please"
[16:38:02 CEST] <redrabbit> it looks bad right?
[16:38:05 CEST] <alexpigment> of course
[16:38:07 CEST] <furq> yeah this looks about standard for youtube
[16:38:23 CEST] <redrabbit> alexpigment: sent you the link as well if you wanna check
[16:38:26 CEST] <alexpigment> k
[16:38:30 CEST] <furq> this will have been reencoded fyi
[16:38:34 CEST] <redrabbit> furq: ok, good to know
[16:38:43 CEST] <redrabbit> it looked crappy to me
[16:38:44 CEST] <furq> live streams get reencoded for archival
[16:38:51 CEST] <furq> so the actual live stream might have looked fine
[16:38:59 CEST] <redrabbit> was similar
[16:39:03 CEST] <redrabbit> kinda
[16:39:07 CEST] <redrabbit> i don't know ^^
[16:39:18 CEST] <alexpigment> actually, this is kinda low for youtube
[16:39:28 CEST] <alexpigment> what bitrate was being sent to them?
[16:39:33 CEST] <redrabbit> 5Mpbs
[16:39:33 CEST] <furq> i tried the 1440p60 stream and it still looks mediocr
[16:39:34 CEST] <furq> e
[16:39:41 CEST] <furq> yeah 5mbps is really low for 1440p60
[16:39:44 CEST] <redrabbit> i guess i should go back to 1080p
[16:39:45 CEST] <alexpigment> 5Mbps is too low imho
[16:39:50 CEST] <furq> youtube uses like 20mbps for 1440p
[16:40:00 CEST] <redrabbit> yeah makes sense
[16:40:07 CEST] <alexpigment> furq: are you sure about that?
[16:40:15 CEST] <furq> pretty sure
[16:40:18 CEST] <alexpigment> i've got some 2160p clips somewhere around here
[16:40:21 CEST] <alexpigment> lemme see what they use
[16:40:22 CEST] <furq> it's significantly higher than 1080p60
[16:40:31 CEST] <furq> maybe 15 for 1440p and 20 for 2160p
[16:40:33 CEST] <furq> i've not checked in a while though
[16:40:50 CEST] <redrabbit> is there better than youtube quality wise
[16:40:54 CEST] <alexpigment> yes
[16:40:58 CEST] <alexpigment> vimeo has always been better
[16:41:06 CEST] <redrabbit> do they reencode your stream when you live stream ?
[16:41:09 CEST] <alexpigment> although they don't have a livestream platform if that's what you're asking about
[16:41:12 CEST] <furq> redrabbit: no
[16:41:14 CEST] <furq> only for archival
[16:41:18 CEST] <redrabbit> ok, good to know
[16:41:20 CEST] <furq> 264          mp4        2560x1440  DASH video 12166k , avc1.640032, 30fps, video only, 273.52MiB
[16:41:26 CEST] <furq> that was the first match for "4k"
[16:41:33 CEST] <furq> hopef someone has a 1440p60 stream around
[16:41:40 CEST] <redrabbit> what would be the best settings on OBS for 5mbps ?
[16:41:41 CEST] <furq> s/stream/video/
[16:41:48 CEST] <furq> i'd probably go with 720p60 at 5mbit
[16:41:52 CEST] <redrabbit> thanks
[16:42:09 CEST] <alexpigment> i agree - 720p60 is a safer bet. that's what most people on twitch use for similar reasons
[16:42:27 CEST] <alexpigment> allows you to have good quality HD with smooth motion, and most people can stream it at reasonable bitrates
[16:42:34 CEST] <redrabbit> yeah my stream looks super blocky
[16:42:36 CEST] <alexpigment> also no hardware acceleration issues on older devices
[16:42:37 CEST] <furq> yeah and youtube gives a decent bump to 60fps stuff
[16:42:50 CEST] <furq> it usually looks nicer in addition to being smoother
[16:43:07 CEST] <alexpigment> there was a while where 720p in general looked better than 1080p on youtube
[16:43:18 CEST] <alexpigment> i'm not sure if that is still true, but it wouldn't surprise me
[16:43:26 CEST] <furq> mine defaults to 720p anyway
[16:43:47 CEST] <redrabbit> i picky highest quality available usually
[16:43:59 CEST] <redrabbit> for that case looks like im gonna switch to 720p
[16:44:05 CEST] <furq> i have also noticed that vp9 generally does better at every resolution
[16:44:21 CEST] <redrabbit> no hw encoders th o
[16:44:24 CEST] <furq> much better in some cases
[16:44:34 CEST] <furq> and yeah i didn't mean uploading vp9
[16:44:52 CEST] <furq> i've seen a few youtube videos that were rate starved all to hell before the vp9 version finished processing
[16:45:04 CEST] <furq> and then the vp9 version looks absolutely fine
[16:45:25 CEST] <furq> usually pathological stuff like old arcade games when the screen gets super busy
[16:48:48 CEST] <alexpigment> for what it's worth, i just found a fairly high motion video on youtube, and here's what I'm seeing for the bitrates (in case this is helpful for anyone)
[16:49:04 CEST] <alexpigment> 720p = 2239Kbps
[16:49:22 CEST] <alexpigment> 1080p = 4271Kpbs
[16:49:34 CEST] <alexpigment> 1440p = 10.1Mbps
[16:49:47 CEST] <alexpigment> 2160p = 22.3Mbps
[16:49:51 CEST] <furq> are those all vp9
[16:49:58 CEST] <furq> also is that 60fps
[16:50:00 CEST] <alexpigment> nope, all H.264
[16:50:02 CEST] <alexpigment> nope
[16:50:06 CEST] <alexpigment> 30fps
[16:50:12 CEST] <alexpigment> just throwing that out there
[16:50:49 CEST] <alexpigment> still, it's good to know they're going up to 22Mbps for 2160p
[16:51:00 CEST] <alexpigment> should be adequate for decent H.264
[16:51:29 CEST] <furq> http://vpaste.net/pazl1
[16:51:33 CEST] <furq> that's pretty typical
[16:52:55 CEST] <alexpigment> so it looks like they only do webm for 60fps?
[16:53:40 CEST] <alexpigment> well, i guess Dash as well... i don't really understand what dash is. i need to read up on that
[16:56:13 CEST] <furq> "DASH video" is h264
[16:56:21 CEST] <alexpigment> yeah, i was just thinking that
[16:56:29 CEST] <furq> i'm pretty sure they do webm over dash as well, so idk why youtube-dl calls it that
[16:56:31 CEST] <alexpigment> do the dash videos all dynamically switch between each other?
[16:56:43 CEST] <furq> yeah it's much the same as hls
[16:56:45 CEST] <alexpigment> or does each dash stream contain lower resolutions.
[16:56:48 CEST] <alexpigment> ?
[16:57:17 CEST] <furq> it'll dynamically switch quality based on bandwidth etc
[16:58:05 CEST] <furq> and also it conveniently provides a degraded experience on iOS
[16:58:10 CEST] <alexpigment> right, but does it jump from 1080p dash to 720p dash dynamically, or does the 1080p have a 360p stream build in that it degrades to
[16:58:12 CEST] <furq> because those guys are stuck using the http streams which cap at 720p
[16:58:37 CEST] <alexpigment> i guess the former seems more logical
[16:58:38 CEST] <furq> it's the same as hls, you get a bunch of playlist files with segments and it'll switch between playlists
[16:58:43 CEST] <alexpigment> gotcha
[16:58:45 CEST] <alexpigment> ok, thanks
[16:58:57 CEST] <alexpigment> i see the word a lot but i've never really looked into it for whatever reason
[16:59:12 CEST] <furq> it's very similar to hls but it's got "MPEG" in the name and also it's not made by apple
[16:59:19 CEST] <alexpigment> ah
[16:59:43 CEST] <dystopia_> hls is anoying
[16:59:55 CEST] <c_14> and uses xml because reasons
[17:00:06 CEST] <furq> but yeah you need to use a thirdparty app for anything over 720p on iOS
[17:00:20 CEST] <furq> because they refuse to support mpeg-dash (unless you're on netflix.com)
[17:00:33 CEST] <furq> you'd think apple would love anything with mpeg in the name
[17:06:03 CEST] <alexpigment> apple often actively blocks technologies that they don't financially benefit from
[17:06:14 CEST] <alexpigment> which is why quicktime won't play MPEG-4 files with MP3 audio
[17:06:22 CEST] <alexpigment> (unless you rename to F4V, curiously)
[17:06:57 CEST] <furq> well they're pretty much the only ones going all in with hevc and ignoring av1
[17:06:59 CEST] <kerio> quicktime player on macos doesn't support hevc :c
[17:07:06 CEST] <furq> lol really
[17:07:14 CEST] <furq> that'll have to change quick
[17:07:53 CEST] <furq> iOS 11 is going full-on hevc for everything afaik
[17:07:56 CEST] <furq> including for images
[17:08:49 CEST] <furq> which is good because there are no other new lossy image formats that are just starting to gain widespread support
[17:09:01 CEST] <furq> certainly not any made by google
[17:11:10 CEST] <kerio> :^)
[17:12:08 CEST] <kerio> well i can't open the x265 example mp4 on safari ios either
[17:12:53 CEST] <kerio> so whaddayaknow
[17:19:02 CEST] <furq> nice
[17:25:36 CEST] <ritsuka> kerio: it's supported in 10.13 and iOS 11, that will be out next month
[17:25:42 CEST] <kerio> ;o
[17:25:47 CEST] <kerio> yay
[17:25:49 CEST] <kerio> do i get hwaccel tho
[17:25:58 CEST] <kerio> iphone 7 and oldish mbp
[17:26:06 CEST] <ritsuka> but only hvc1 fourcc, so probably files from ffmpeg won't work
[17:26:09 CEST] <ritsuka> yes if you have a recent intel cpu or iphone 7 and later
[17:46:22 CEST] <dan3wik> Does -video_size change input resolution and -s changes output?
[17:47:25 CEST] <BtbN> how would you change input resolution?
[17:57:42 CEST] <kepstin> many webcams have selectable resolution, for example
[17:58:35 CEST] <kepstin> dan3wik: on input devices with selectable resolution, the '-video-size' input avoption can be used to select which resolution to use
[17:59:03 CEST] <kepstin> while the -s output option adds a scale filter on the output to rescale everything to your desired resolution
[17:59:12 CEST] <dan3wik> Oh yeah, Its for a webcam. So I can use that?
[17:59:24 CEST] <dan3wik> Cool, ok. thanks
[17:59:39 CEST] <kepstin> er, -video_size
[17:59:45 CEST] <kepstin> underscore, not dash :/
[18:00:31 CEST] <dan3wik> Ok, thanks. The man page on pi just says "Changes the desired frame size"
[18:00:38 CEST] <dan3wik> for both of them
[18:01:17 CEST] <kepstin> I *think* that if you use -s as an input option, the ffmpeg cli tool maps it to the -video_size option for you, but I haven't confirmed that
[18:06:45 CEST] <dan3wik> Ok. I was just checking because I script I am looking at uses -video_size as a fixed value and allows -s to be adjusted with arguments.
[18:07:39 CEST] <dan3wik> The coded in -video_size is 320x240 and the default -s is 1080x1920
[18:07:48 CEST] <dan3wik> I thought it was a little odd
[18:27:24 CEST] <niklob> Hello guys, why do I get the "[dvbsub @ 00000000025eb520] [IMGUTILS @ 00000000079ef680] Picture size 0x0 is invalid" and how to fix this?? https://pastebin.com/6fL5KmEc
[18:32:11 CEST] <dystopia_> i don't think it can handle that subtitle format
[18:33:46 CEST] <dystopia_> hmm if it's .srt just mux them in with mkvmerge
[18:34:51 CEST] <niklob> my recorder can't handle srt
[18:34:56 CEST] <niklob> only dvb
[19:32:45 CEST] <niklob> so ffmpeg can't covnert .srt to dvb?
[19:33:59 CEST] <JEEB> it could, but it doesn't
[19:34:11 CEST] <JEEB> because you would have to first render the subtitle with libass
[19:34:23 CEST] <JEEB> then convert it to an image format that the DVB subtitle encoder likes
[19:35:16 CEST] <JEEB> basically, it doesn't just work decode->encode
[19:45:16 CEST] <kerio> lib ass 🤤
[20:30:11 CEST] <niklob> how do i render with libAss?
[20:30:58 CEST] <JEEB> there's a filter for that already which takes in ASS files, so you'd have to extend that one to take subtitle AVFrames :P
[20:31:17 CEST] <JEEB> or you write similar logic on the client side (libass returns RGB pictures back)
[21:25:02 CEST] <paveldimow> Hi, anyone can explain why each mpeg packet in mpegts has different PTS? I would expect that every packet that is part of one picture/frame has the same PTS, or I am wrong?
[21:25:26 CEST] <JEEB> at the point where you are getting packets they are no longer MPEG-TS packets
[21:25:32 CEST] <JEEB> they are packets of those streams
[21:26:28 CEST] <paveldimow> JEEB: hmmm, then what does ffprobe -show_packets -select_streams v sample.mp4 shows?
[21:27:01 CEST] <paveldimow> it shows mpeg packets or not?
[21:28:04 CEST] <JEEB> paveldimow: it shows packets that are gotten for different streams from the demuxer
[21:28:10 CEST] <JEEB> it is not mpeg-ts packets
[21:28:24 CEST] <JEEB> libavformat abstracts the mpeg-ts away from you
[21:35:38 CEST] <paveldimow> JEEB: but in mpegts then all packets in the same frame have same PTS?
[21:37:03 CEST] <JEEB> no idea, haven't looked at the packets that much recently :P
[21:37:12 CEST] <paveldimow> :D
[21:42:53 CEST] <peloverde> Has anyone had luck building ffmpeg with mingw-w64 clang?
[21:44:07 CEST] <durandal_1707> what, theres error?
[21:44:34 CEST] <peloverde> multiple definitions of various GUIDs
[21:44:59 CEST] <peloverde> e.g. C:\msys64\mingw64\x86_64-w64-mingw32\lib/libstrmiids.a(lib64_libstrmiids_a-strmiids.o):strmiids.c:(.rdata$IID_ICodeInstall[IID_ICodeInstall]+0x0): multiple definition of `IID_ICodeInstall'
[21:44:59 CEST] <peloverde> libavcodec/libavcodec.a(dxva2.o):D:/dev/ffmpeg/ffmpeg/libavcodec/dxva2.c:639: first defined here
[21:49:25 CEST] <JEEB> peloverde: I remember someone bringing that up, but not sure if it was a mingw-w64 thing or an FFmpeg thing.
[21:49:33 CEST] <JEEB> is that with current FFmpeg?
[21:50:44 CEST] <peloverde> yes, it's with current master ffmpeg and current msys2 mingw-w64 clang
[21:52:43 CEST] <JEEB> ah yes
[21:52:46 CEST] <JEEB> seems like a mingw-w64 thing
[21:52:47 CEST] <JEEB> https://sourceforge.net/p/mingw-w64/mailman/mingw-w64-public/thread/cd50f3c1-d686-9fc2-b473-4b83fddf51fd%40126.com/
[21:53:07 CEST] <paveldimow> Is this channel the right place to ask/offer job for ffmpeg developer?
[21:53:09 CEST] <JEEB> at least this is GUID declaration fixing
[21:53:41 CEST] <JEEB> paveldimow: do you need someone to work on the insides of FFmpeg or creating an API client that utilizes FFmpeg's libraries?
[21:54:29 CEST] <paveldimow> I need someone to add the support for amf0 in ffmpeg
[21:54:35 CEST] <JEEB> right
[21:54:45 CEST] <JEEB> I recommend poking the ffmpeg-devel mailing list or so
[21:54:59 CEST] <paveldimow> JEEB: Tnx!
[21:55:07 CEST] <JEEB> wait
[21:55:10 CEST] <JEEB> actionscript?
[21:55:17 CEST] <durandal_1707> amf0 is what?
[21:55:27 CEST] <JEEB> durandal_1707: http://wwwimages.adobe.com/content/dam/Adobe/en/devnet/amf/pdf/amf0-file-format-specification.pdf
[21:55:35 CEST] <JEEB> it seems like flash stuff o_O
[21:55:58 CEST] <durandal_1707> new adobe bullshit?
[21:56:10 CEST] <JEEB> old
[21:56:24 CEST] <paveldimow> old "D
[21:56:25 CEST] <JEEB> > AMF 0 was introduced ... 2001.
[21:57:49 CEST] <paveldimow> It's not my fault for sure :) the thing is that Wowza media server write metadata information in amf0 (those are the timestamps) and I need support for this in ffmpeg
[21:58:41 CEST] <JEEB> seems to be utilized in RTMP or so
[21:58:54 CEST] <paveldimow> that's correct
[21:59:07 CEST] <JEEB> lol, rtmp parser in lisp https://github.com/sile/rtmp
[22:00:08 CEST] <paveldimow> with chinese doc.. not tnx :)
[22:00:20 CEST] <JEEB> Japanese but yea
[22:09:41 CEST] <peloverde> the gcc build works fine for me with the same mingw headers/libs :(
[22:09:59 CEST] <JEEB> uh-oh. sounds like that fix I linked might have not worked with clang then
[22:10:38 CEST] <peloverde> I guess we'll see what happens when clang-5 rolls out in the next few weeks
[22:47:03 CEST] <paveldimow> Does anyone can recommend an audio filter that can hmmmm fade? the difference between audio, when combining multiple video clips?
[22:48:15 CEST] <c3-Win> You mean Normalize the audio?
[22:48:42 CEST] <paveldimow> well something like that
[22:49:39 CEST] <paveldimow> for example to cut off some spikes
[22:52:21 CEST] <c3-Win> paveldimow: Lower spikes is either using a limiter or compressor.
[22:55:01 CEST] <paveldimow> c3-Win: One more question can I use audio or video filter only on certain part of audio/video? For example use audio compressor from 00:10:34 to 00:10:36 ?
[22:55:25 CEST] <c3-Win> paveldimow: I can't say,s orry.
[23:29:00 CEST] <dystopia_> [Parsed_setsar_3 @ 000000000412ed80] num:den syntax is deprecated, please use num/den or named options instead
[23:29:11 CEST] <dystopia_> i get this error, when scaling like this "scale=1280:-4,setsar=1:1"
[23:29:26 CEST] <dystopia_> how should i be entering ir?
[23:29:31 CEST] <dystopia_> it*
[23:32:29 CEST] <BtbN> weird, it's interpreting it as a single value
[23:33:33 CEST] <relaxed> the examples say setsar=sar=1/1
[23:37:48 CEST] <dystopia_> will give that a shot relaxed
[23:47:24 CEST] <SpLiC3> when repeating a .ts stream to pipe:1 i can get multiple vlc users on but when kodi users connect the stream buffer cache goes apeshit
[23:48:21 CEST] <SpLiC3> is there any buf/cache options that would help with that, current line is...
[23:51:11 CEST] <SpLiC3> -re -fflags igndts -vsync 1 -i cache:http://someiptv:port/blah.ts -sn -tune zerolatency -map 0 -bufsize 10000k -bsf null -muxrate 10M
[23:53:41 CEST] <SpLiC3>  -re -fflags igndts -vsync 1 -i cache:http://someiptv:port/blah.ts -sn -tune zerolatency -map 0 -bufsize 10000k -bsf null -muxrate 10M -f mpegts
[23:53:46 CEST] <SpLiC3> sorry missed teh -f
[00:00:00 CEST] --- Sat Aug 19 2017


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