[Ffmpeg-devel-irc] ffmpeg.log.20191006

[burek]

[00:10:42 CEST] <la_mettrie> i have 1.3 G large and 20 minutes long avi-file. trying to figure out how to make it considerably smaller mkv file
[00:11:25 CEST] <la_mettrie> (reducing the size may mean reducing the quality, then i want to reduce quality which has the least visible effect)
[00:38:41 CEST] <DHE> well what's it like now? pastebin the output of ffprobe on it
[00:38:51 CEST] <DHE> get an idea of what we're dealing with
[00:39:55 CEST] <la_mettrie> okay, i haven't been dealing a lot with videos and thought that it's excessively big but now i heard that maybe it isn't
[00:40:15 CEST] <DHE> could be. depends what it is. that's why I ask for ffprobe output
[00:40:47 CEST] <DHE> might be as simple as the audio is uncompressed and turning it into AAC is a huge win in a matter of 30 seconds of compression
[00:42:21 CEST] <la_mettrie> well, here's the output  https://pastebin.com/raw/z4iUdk7X
[00:42:48 CEST] <DHE> mpeg4 classic... well that's old.
[00:43:11 CEST] <DHE> also vorbis in an AVI...
[00:43:46 CEST] <DHE> but for 480p yeah that's pretty big...
[00:44:41 CEST] <DHE> try this: ffmpeg -i videofile.avi -c:a copy -c:v libx264 -qp 23 output.mkv # this may take 3-10 minutes depending on CPU power
[00:45:15 CEST] <la_mettrie> danke
[00:57:02 CEST] <la_mettrie> ok, the resulting file has sound broken
[01:19:34 CEST] <DHE> la_mettrie: darn.. okay. but was the image quality ok?
[01:19:38 CEST] <DHE> plus file size and all that
[01:34:49 CEST] <Atlenohen> Hey, so ffmpeg support two versions of FFV1, didn't know that. Since when?
[01:35:20 CEST] <Atlenohen> I'd like to read somewhere what the benefits of version 3 are (level)
[01:35:36 CEST] <Atlenohen> Avisynth can't decode it tho
[02:47:15 CEST] <trfl> I'm trying to use ffmpeg to verify mkv files for errors; currently I have the following command: ffmpeg -y -hide_banner -nostdin -v info -err_detect +crccheck+bitstream+buffer+careful+compliant+aggressive+explode -xerror -i "$fn" -codec copy -f null -
[02:48:09 CEST] <trfl> I am expecting this to return non-zero for most/all errors, however certain conditions print a warning yet return 0, for example:  [matroska,webm] Element at 0x8888888 ending at 0x9999999 exceeds containing master element ending at 0x9494949
[02:48:55 CEST] <trfl> am I expected to check the stderr for anything that's colorcoded red? is there anything I have misunderstood so far, for example how to set the err_detect flags?
[09:04:09 CEST] <la_mettrie> when trying to play avi-file with VLC, it complains that file's index is missing or broken.  then VLC let's generate index or to play file without it.  when playing without index, there's glitch on the screen now and then.
[09:04:24 CEST] <la_mettrie> now should something be done for this while before uploading to youtube and other places?
[09:04:36 CEST] <la_mettrie> *lets
[09:04:57 CEST] <la_mettrie> *while -> file
[09:10:36 CEST] <la_mettrie> okay, mplayer seems not to play that file all
[09:23:16 CEST] <la_mettrie> probably ffmpeg could somehow generate that index so that it would be always there
[09:45:01 CEST] <la_mettrie> okay, now it's possible that i fixed the problem by using a different command to impose the sound on the video
[09:52:40 CEST] <la_mettrie> cannot believe how fastly ffmpeg inserted that 20 min long OGG to a mkv file (of the same duration)
[00:00:00 CEST] --- Mon Oct  7 2019