[Ffmpeg-devel-irc] ffmpeg.log.20191228

[burek]

[07:46:52 CET] <AiNA_TE> how do i set "Average quantizer" value in ffmpeg?
[07:47:59 CET] <AiNA_TE> and is it known by some other name?, i don't see it in the documentation
[09:37:41 CET] <celebrate> hey everyone
[09:37:55 CET] <celebrate> How can i make the scaling option respect aspect ratio of the video?
[09:37:56 CET] <celebrate> .outputOptions(['-s 480:600','-c:a copy', '-c:v libx264', '-preset:v medium'])
[09:38:06 CET] <celebrate> i tried 480:-1 for example but that didn't work
[09:38:08 CET] <celebrate> here's full my cmd
[09:38:13 CET] <celebrate> ffmpeg()        .input(tempFilePath)        .input(watermarkFilePath)        .outputOptions(['-s 480:600','-c:a copy', '-c:v libx264', '-preset:v medium'])        .complexFilter([            "[0:v][1:v]overlay=W-w-20:H-h-20"        ])        .format('mp4')        .output(targetTempFilePath)
[09:39:16 CET] <celebrate> It gave me an error when i tried: Invalid frame size: 480:-1.
[09:39:28 CET] <celebrate> The top example works but doesnt respect aspect ratio
[12:23:11 CET] <sopparus> hello
[12:24:31 CET] <sopparus> a few years ago I used some ffmpeg or possibly mkvtools to find mkvs that kodi couldnt jump to positions in, to fix it I just remade the mkv. Anyone knows how you can figure this out with cli?
[13:55:21 CET] <LFSVeteran> ffmpeg -f alsa -acodec pcm_s32le -ac 2 -ar 192k -i hw:1,0 -strict -2 -c:a vorbis -content_type audio/ogg -f ogg icecast://user:pass@127.0.0.1:8000/stream
[13:55:29 CET] <LFSVeteran> how can I add buffering to this?
[13:55:42 CET] <LFSVeteran> the stream is working, but faltering
[14:58:49 CET] <relaxed> LFSVeteran: you probably want '-c:a libvorbis', ffmpeg has a native encoder called 'vorbis' and it sucks.
[15:15:15 CET] <scramblez> Hi All, I have an mp4 with a mono aac audio stream in it. How could I map it to individual channels at a time? e.g. how could I map it to come out only on FR, or only on LFE?
[15:16:36 CET] <scramblez> while the other channels stay silent/empty?
[15:17:24 CET] <scramblez> Also, convert it to ac3 at the same time?
[15:19:29 CET] <scramblez> Ahh ... 'channelmap' may be what I need ...
[15:22:33 CET] <relaxed> scramblez: look at the channelmap filter
[15:22:39 CET] <relaxed> oh, nm :)
[15:23:11 CET] <scramblez> relaxed: thanks, I'm reading up on it now.  :-)
[15:24:25 CET] <scramblez> Hmm ... struggling with this.
[15:24:51 CET] <scramblez> I have a single mono aac audio. How do I direct it with channelmap?
[15:25:05 CET] <scramblez> Say to only play out of FR?
[15:25:31 CET] <scramblez> What should the channelmap input be for a mono?
[15:26:11 CET] <scramblez> Maybe I need to map the audio stream 0:1?
[15:26:37 CET] Action: scramblez back in a while ...
[15:35:14 CET] <vlt> Hello. Is there a filter for shearing video? Im looking for a quick way to move just the lower left corner of a video up by a few pixels. Any idea?
[15:38:35 CET] <Hello71> don't think so. if you're just editing one video it's probably easier to just load some graphical video editor
[15:40:31 CET] <vlt> I found "perspective" which almost does what I need.
[15:41:23 CET] <vlt> Any idea how to fill missing parts with black background instead of repeating the pixels of the last line?
[15:51:20 CET] <LFSVeteran> relaxed: ah that explains why libvorbis isn't working...it says unknown encoder
[15:51:47 CET] <LFSVeteran> checking configure how to enable the system one...
[15:53:55 CET] <durandal_1707> vlt: you can add fillborders filter
[16:00:45 CET] <LFSVeteran> rebuilding ffmpeg with correct vorbis support
[16:24:42 CET] <vlt> durandal_1707: Trying that, thanks.
[16:43:10 CET] <sopparus> anyone know how to detect missing or bad index in a mkv file using ffmpeg or mkvtools?
[18:35:33 CET] <LFSVeteran> hmm libvorbis won't allow 192kHz sample rate
[18:35:48 CET] <LFSVeteran> while I can do with vorbis
[18:36:18 CET] <BtbN> Why would you even need that high of a samplerate?
[18:36:26 CET] <BtbN> Doesn't that mess with players which most likely don't support it?
[18:37:15 CET] <LFSVeteran> forgot to mention it isn't just audio what I want to stream...
[18:37:59 CET] <BtbN> That makes that sample rate even more questionable
[18:38:12 CET] <LFSVeteran> so for normal audio, correct, 44kHz would be sufficient
[18:38:35 CET] <LFSVeteran> the max freq is about 60kHz
[18:38:59 CET] <LFSVeteran> which is possible with alsa and the soundcard
[18:39:28 CET] <BtbN> But not with the vast majority of speakers, headphones and ears.
[18:40:18 CET] <LFSVeteran> no indeed, you'll need some filtering there....that's what happens, audio gets separated from the rest
[18:41:12 CET] <LFSVeteran> maybe just plain pcm_s32le?
[18:49:59 CET] <furq> applying audio compression to non-audio data is generally a bad idea
[18:51:00 CET] <furq> lossy compression is much more likely to lose stuff you care about and lossless compression probably won't compress it very well
[18:52:56 CET] <LFSVeteran> options for non compressed codecs/formats?
[00:00:00 CET] --- Sun Dec 29 2019