Re: [gentoo-user] Re: ffmpeg video+audio capture question
On Tue, 24 Sep 2019 at 04:56, Ian Zimmerman wrote: > > On 2019-09-23 16:22, Walter Dnes wrote: > > > There appear to be "media-sound/jack" and "media-sound/jack2" ebuilds. > > Both of them are tagged "~amd64". There's also > > media-sound/jack-audio-connection-kit Which one(s) do I use? > > It's the last one, I'm pretty sure. media-sound/jack is an old CD ripping application, so this is not what you want. media-sound/jack2 is the C++ coded jack daemon for multi-processor PCs. media-sound/jack-audio-connection-kit is (I think) the jack1 daemon coded in C. For Jack1 Vs Jack2 features have a look here: https://github.com/jackaudio/jackaudio.github.com/wiki/Q_difference_jack1_jack2 > > Youtube is a bad example to use. There are various other HTML5 > > streaming websites, which don't work with youtube-dl. Plus I also want > > to be able to record video games and any other desktop app in general. > > What I want is to "tee" the audio output so that I can record while > > monitoring it. > > Long ago, I digitized my vinyl and audio tape collection this way, with > the input coming over good old analog audio cable. I did it with pure > ALSA, no jack was needed. I _think_ there was a knob either in > alsamixer or in arecord to do the "tee", but I don't really remember. For streaming websites which do not offer a download button, you can launch the browser developer tab, select Network/Media and keep an eye on the traffic as you click on the website to start streaming the video. The developer tab will list the actual path of the video file. Open another tab in the browser and paste the full URL to download it, or you could try curl/wget et al. tee-ing the audio output of desktop applications/windows may be doable with dmix and asoundrc syntax, but I wouldn't know what this looks like today with any certainty - last time I used dmix was in the mid 00s. Anyway, you tried this and it didn't work. Jackd was created for the very purpose of plumbing I/O audio into various configurations, so tweaking it to do the recording you require should be eminently doable and using one of the various Gtk/Qt front ends makes it even easier/quicker. -- Regards, Mick
Re: [gentoo-user] Re: ffmpeg video+audio capture question
> > > Youtube is a bad example to use. There are various other HTML5 > > streaming websites, which don't work with youtube-dl. Plus I also want > > to be able to record video games and any other desktop app in general. > > What I want is to "tee" the audio output so that I can record while > > monitoring it. > > Long ago, I digitized my vinyl and audio tape collection this way, with > the input coming over good old analog audio cable. I did it with pure > ALSA, no jack was needed. I _think_ there was a knob either in > alsamixer or in arecord to do the "tee", but I don't really remember. > When you're digitising audio you can just connect the tape/LP output to a line in input. AFAICT the "tee" is only needed for capturing digital output that's coming from the PC itself. Also, for LPs, if you don't run the LP output into an amplifier phono input, it will miss out on the EQ reversal that occurs there. The physical characteristics of vinyl media mean that some frequencies are harder to encode in a vinyl groove than others (cant remember if its high or low freqs) so as part of the manufacturing process they put the signal through a filter before its written to vinyl, then the phono input on the amp reverses that filter to restore the signal. I'd imagine you could use a digital EQ to restore the signal if you don't have an amp with phono input handy.
[gentoo-user] Re: ffmpeg video+audio capture question
On 2019-09-23 16:22, Walter Dnes wrote: > There appear to be "media-sound/jack" and "media-sound/jack2" ebuilds. > Both of them are tagged "~amd64". There's also > media-sound/jack-audio-connection-kit Which one(s) do I use? It's the last one, I'm pretty sure. > Youtube is a bad example to use. There are various other HTML5 > streaming websites, which don't work with youtube-dl. Plus I also want > to be able to record video games and any other desktop app in general. > What I want is to "tee" the audio output so that I can record while > monitoring it. Long ago, I digitized my vinyl and audio tape collection this way, with the input coming over good old analog audio cable. I did it with pure ALSA, no jack was needed. I _think_ there was a knob either in alsamixer or in arecord to do the "tee", but I don't really remember. -- Please don't Cc: me privately on mailing lists and Usenet, if you also post the followup to the list or newsgroup. To reply privately _only_ on Usenet and on broken lists which rewrite From, fetch the TXT record for no-use.mooo.com.
