[Ffmpeg-devel-irc] ffmpeg.log.20190503

[burek]

[02:16:49 CEST] <another> is a rgb24 -> bgr0 conversion lossless?
[02:38:55 CEST] <c_14> should be, they're both 8bit rgb encodings
[02:41:54 CEST] <c_14> I just tested, and rgb24 -> bgr0 -> rgb24 was lossless with ffmpeg
[02:57:19 CEST] <another> right, i could have simply used the hash muxer and try it myself
[02:57:21 CEST] <another> thank c_14
[04:22:59 CEST] <kepstin> another: the only differences between rgb24 and bgr0 are that the pixels are padded with an extra 0 byte so each pixel is on 32bit boundaries, and the order that colours are stored is switched.
[04:43:40 CEST] <another> i figured that by now
[04:43:57 CEST] <another> but the amount of pixel formats is insane
[04:52:12 CEST] <another> btw: i noticed something: i encoded some png's to ffvhuff
[04:52:32 CEST] <another> output indicated rgb24 -> rgb24
[04:54:43 CEST] <another> however ffprobe on the resulting file show bgr0
[04:55:21 CEST] <another> which isn't even listed as a supported pixel format for ffvhuff
[04:57:31 CEST] <another> even forcing rgb24 with -pix_fmt produces bgr0
[05:01:35 CEST] <furq> bgr0 is just little endian rgb24
[05:01:47 CEST] <furq> so i assume it stores that internally for some good reason
[05:01:57 CEST] <furq> not sure why it wouldn't be an accepted input format though
[05:29:17 CEST] <kepstin> could just be that the encoder and decoder were written differently, so the input from/output to different rgb formats
[05:29:26 CEST] <kepstin> since the formats are otherwise equivalent
[13:57:43 CEST] <kandinski> -window close
[15:06:57 CEST] <GuiToris> hey, is there a list somewhere with the official standard vorbis (flac/ogg) tags?
[15:08:14 CEST] <BtbN> I don't think such a thing exists
[15:08:38 CEST] <GuiToris> how should I refer to the original author?
[15:08:45 CEST] <BtbN> What do you mean?
[15:09:31 CEST] <GuiToris> if I see an mp3 file with mediainfo I see a line : Original/Performer
[15:09:48 CEST] <BtbN> mp3 uses id3 mostly
[15:10:19 CEST] <GuiToris> but I assume there's also a similar line in flac/ogg files
[15:10:40 CEST] <GuiToris> I could set all of them but this one
[15:45:27 CEST] <kepstin> GuiToris: the only "official" vorbis tag names are the one shown here: https://xiph.org/vorbis/doc/v-comment.html
[15:45:45 CEST] <kepstin> GuiToris: in musicbrainz, we use this expanded list: https://picard.musicbrainz.org/docs/mappings/
[15:47:14 CEST] <GuiToris> thanks kepstin
[15:48:13 CEST] <GuiToris> do you happen to know how to add cover art to ogg vorbis? the manual says 'METADATA_BLOCK_PICTURE' but what is this? A command line option?
[15:48:46 CEST] <GuiToris> I've tried it and it said: WARNING: maximum bitrate "ETADATA_BLOCK_PICTURE=./image.jpg" not recognized
[15:50:10 CEST] <kepstin> i'm not sure whether ffmpeg actually supports it?
[15:50:46 CEST] <kepstin> cover art in ogg vorbis stuff is a hack - iirc it takes a flac cover art frame, then base64 encodes it, then throws it in a text comment
[15:59:28 CEST] <GuiToris> ahh, you must be right
[15:59:59 CEST] <GuiToris> shoot, this seems to be difficult
[17:19:16 CEST] <fleabeard> hello friends, using this command https://hastebin.com/roqegamaxo.nginx in the CLI on a video that is mkv, 10-bit h265 with subtitles.The problem I'm having is once it's done, the subtitles aren't there anymore and I thought they should be since I'm not using the -sn switch. Any ideas how I can get subtitles working?
[17:22:06 CEST] <kepstin> fleabeard: ... and the console log output from the ffmpeg command?
[17:23:23 CEST] <fleabeard> kepstin, actually I think I may have solved my issue just now. The -map removes embedded subtitle streams I just learned so I'm gonna try it without the use of -map :)
[17:24:21 CEST] <kepstin> if you use -map it disables the default mapping, and instead only includes streams you explicitly specify
[17:26:27 CEST] <fleabeard> good to know! I've only been using ffmpeg for 2 days hehe, got lots to learn.
[17:43:58 CEST] <ptx0> if i have two videos (A, B) and want to interleave the frames so it goes ABABABAB.. how do i go about this?
[17:45:14 CEST] <ptx0> do i have to make folders full of frames and manage the filenames with a script or something
[18:06:26 CEST] <pink_mist> oh hey ptx0, ltns
[18:30:14 CEST] <durandal_1707> ptx0: there is special filter just for that
[18:41:18 CEST] <ptx0> any more info?
[18:42:49 CEST] <DHE> need to give it a shot, but I'm guessing either mix or tmix
[18:46:10 CEST] <durandal_1707> DHE: nope, you are wrong
[18:58:09 CEST] <durandal_1707> ptx0: -lavfi interleave,settb=1/48,setpts=N  where 48 = 2 * FPS
[18:59:07 CEST] <durandal_1707> question is do you need to double FPS? or make everything 2x slower?
[18:59:27 CEST] <ptx0> 2x slower is fine, it's just combining two halves of a timelapse
[19:02:01 CEST] <durandal_1707> interleave,settb=1/24,setpts=N  where 24 is original FPS of A/B
[19:02:48 CEST] <ptx0> thanks
[19:11:42 CEST] <Visitorer> How can I get ffmpeg to show me all the options for h264?
[19:12:42 CEST] <durandal_1707> for encoder?
[19:12:47 CEST] <Visitorer> Yes
[19:14:56 CEST] <another> ffmpeg -h encoder=h264 shows *some* options but not all
[19:15:22 CEST] <another> i think it just shows the encoder specific options
[19:15:56 CEST] <another> you can check the manpage too
[19:16:23 CEST] <Visitorer> Thank you that's what I needed
[19:18:08 CEST] <another> e.g. https://www.ffmpeg.org/ffmpeg-codecs.html#libx264_002c-libx264rgb
[20:04:09 CEST] <cehoyos> Visitorer: In case you have asked about x264 (as opposed to "h264"), FFmpeg cannot show you all options, as there is "-x264-params" which passes options to libx264 that are unknown to FFmpeg.
[20:04:29 CEST] <Visitorer> I see. Thank you
[22:47:57 CEST] <GuiToris> hello.... shoot this is terrible, I'm unable to add coverart to my ogg files. I've even tried using vorbiscomment but it seems I'm out of luck
[22:48:13 CEST] <GuiToris> does anyone have some experience on this field?
[00:00:00 CEST] --- Sat May  4 2019