[Ffmpeg-devel-irc] ffmpeg.log.20170723

[burek]

[01:30:54 CEST] <wondiws> how do I stream my webcam? I start ffserver, but when I connect to it, the "Connection is reset by peer" after half a second
[01:31:41 CEST] <wondiws> and connection refused before that
[09:59:40 CEST] <Blubberbub> When one uses avutil/common.h and Python.h in the same .c file one gets warning about some macros being redefined.
[13:56:24 CEST] <faLUCE>  I'm noting that the h264 decoder which I use (gstreamer's avdec_h264) wants that each NALUs starts with a "0, 0, 2, 9, 240, 0, 0, 0"  header... In fact, it uses the output of a h264 parser, which  takes a normal header (0, 0, 0, 1) as input and outputs the other header. What is that? Is it possible to obtain it while encoding with ffmpeg/x264?
[17:01:09 CEST] <momomo> does ffmpeg support h265  ?
[17:03:13 CEST] <Threads> momomo if compiled with it yes
[17:04:00 CEST] <Threads> momomo https://trac.ffmpeg.org/wiki/Encode/H.265
[20:02:24 CEST] <dystopia_> what sort of tool would i need to blur some sensitive information in a video
[20:02:40 CEST] <dystopia_> like i want to hide an address that is visable for a few seconds
[20:05:57 CEST] <thebombzen> dystopia_: your best bet is probably just an NLE. But something you could do is during the sensitive part, chain use crop, blur, and overlay.
[20:06:49 CEST] <thebombzen> during the sensitive part you can split the video into two streams, crop the second on to just the address, pad it with transparency so it's the same position as before, blur it, and then overlay it atop the first stream from the split
[20:06:59 CEST] <thebombzen> this is all complicated, and you probably just want to use a nonlinear editor
[20:19:35 CEST] <furq> dystopia_: drawbox with enable
[20:20:42 CEST] <furq> drawbox=123:456:78:90:enable=between(t\,100\,105)
[20:21:36 CEST] <furq> delogo will do the same thing if you want something less jarring
[20:58:57 CEST] <yegortimoshenko> where can i see the list of album cover art mime types that ffplay supports by default?
[21:34:42 CEST] <dystopia_> thanks for the ideas thebombzen and furq, will do some testing
[22:16:01 CEST] <thebombzen> yegortimoshenko: you can use ffmpeg -decoders and ffmpeg -demuxers to see what is supported
[22:16:42 CEST] <thebombzen> embedded album art should be supported as long as it's on that list. given that usually it's some fairly standard image format (e.g. jpg) you shouldn't have to worry
[22:17:02 CEST] <yegortimoshenko> thebombzen: no, i'm interested in more exotic formats which is why i'm asking. thanks!
[22:17:27 CEST] <thebombzen> well then you can use ffmpeg -decoders and ffmpeg -demuxers to see what's supported
[22:17:52 CEST] <thebombzen> it doesn't list MIME types because ffmpeg doesn't care what MIME type something is
[22:17:58 CEST] <thebombzen> you'll have to do that part yourself
[22:18:28 CEST] <yegortimoshenko> i'm ok with just formats themselves, it's just when you embed an artwork into a flac file, you have to specify a mime type
[22:19:04 CEST] <thebombzen> well that's the job of the person embedding it. FFmpeg doesn't care what MIME type it is, it cares what codec or format it is
[22:19:48 CEST] <thebombzen> if the flac file format uses MIME as its identifier, then the flac demuxer will abstract that away from you so you don't need to worry about it
[22:20:28 CEST] <yegortimoshenko> flac metadata uses mime type as a format identifier
[22:20:35 CEST] <yegortimoshenko> got it
[22:51:25 CEST] <thisIsJustARando> hello, anyone online who knows something alittle more advanced than usually?
[22:51:43 CEST] <JEEB> it's probably worth it just asking
[22:51:50 CEST] <JEEB> and waiting around if someone can respond
[22:52:58 CEST] <thisIsJustARando> well, I was just wondering, is it possible to use ffmpeg to convert files on chunks, like, first convert first 30seconds of video, then from 30seconds to 1minute, then 1minute to 2minute etc
[22:53:16 CEST] <thisIsJustARando> I have not readed anything yet about ffmpeg
[22:53:28 CEST] <thisIsJustARando> figured I would ask before starting to read anything
[22:54:24 CEST] <JEEB> basically, ffmpeg.c won't do such threading but X companies have based their stuff on using the FFmpeg libraries either straight or through wrappers
[22:59:42 CEST] <thisIsJustARando> would also be acceptable if it was possible to convert from x seconds to y seconds, or even better yet, frames
[23:00:46 CEST] <JEEB> there's a seek and "process this long"/"process this many frames" parameters in ffmpeg.c, the libraries themselves let you do even more
[23:01:02 CEST] <JEEB> when I talk of ffmpeg.c, it's the command line tool that comes with FFmpeg
[23:01:24 CEST] <thisIsJustARando> yes, I wouldn't use any other than cli tool
[23:02:20 CEST] <JEEB> ok, then I will warn you that since ffmpeg.c doesn't index the file before starting work, any seeks could in theory be non-exact
[23:02:29 CEST] <JEEB> although for many formats they are
[23:02:49 CEST] <JEEB> basically, if there's an index, it most likely is exact
[23:03:45 CEST] <JEEB> (although I think ffmpeg.c can't do mixed seeks - where it first seeks to the closest random access point and then decodes to hit the picture with your required timestamp)
[23:04:06 CEST] <JEEB> it has a parameter for each type of seeking though
[23:04:15 CEST] <JEEB> or well, the latter one isn't seeking
[23:04:26 CEST] <JEEB> it's just "decode until timestamp X"
[23:05:05 CEST] <JEEB> there's a library available that wraps around the FFmpeg libraries to index files and that generally provides 100% frame accuracy unless the thing's somehow completely retarded
[23:09:52 CEST] <thisIsJustARando> well, I will read about ffmpeg later this night or tomorrow
[23:11:32 CEST] <JEEB> basically as far as the general "reads, demuxes, decodes, encodes, muxes" thing goes, almost everything uses FFmpeg's libraries in the background. depending on the use case the command line app can either work or not
[00:00:00 CEST] --- Mon Jul 24 2017