Gentoo Archives: gentoo-user

From: Adam Carter <adamcarter3@×××××.com>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] [OT] ffmpeg video+audio capture question
Date: Thu, 19 Sep 2019 02:46:18
Message-Id: CAC=wYCEeNtpT7znDN8nhhQ8kOe7ac+83s-T23Y+=pOKS0SfG7g@mail.gmail.com
In Reply to: Re: [gentoo-user] [OT] ffmpeg video+audio capture question by Walter Dnes
1 On Thu, Sep 19, 2019 at 9:58 AM Walter Dnes <waltdnes@××××××××.org> wrote:
2
3 > On Wed, Sep 18, 2019 at 09:14:44PM +0100, Mick wrote
4 >
5 > > Yes, you only have one card 0. The first device (default) is the
6 > analogue.
7 > >
8 > > What does 'arecord -l' show?
9 >
10 > **** List of CAPTURE Hardware Devices ****
11 > card 0: PCH [HDA Intel PCH], device 0: CX20641 Analog [CX20641 Analog]
12 > Subdevices: 1/1
13 > Subdevice #0: subdevice #0
14 > card 0: PCH [HDA Intel PCH], device 2: CX20641 Alt Analog [CX20641 Alt
15 > Analog]
16 > Subdevices: 1/1
17 > Subdevice #0: subdevice #0
18 > I don't run "desktop environments"; I run useful applications
19 >
20 >
21 I think for what you are trying to do, the capture devices/mic are not
22 relevant - there will be no signal on them. The playback device have the
23 signal, and ffmpeg needs to capture of those signals.
24
25 > -i hw:0,1
26 >
27 > or
28 >
29 > -i hw:0,0,1
30
31 Both fail with No such file or directory.
32
33 FWIW audacity has a drop down list of the output devices, and on my system
34 they're all shown as hw:X,Y. There's no hw:X or hw:X,Y,Z. I also notice
35 that the same hw:X,Y is used for both an playback and capture device, so i
36 guess that means that '-i hw:0.1' is using the hw:0,1 capture device, which
37 for you has no signal, and therefore ffmpeg doesnt capture anything.
38
39 Hopefully there's some way to capture the output digitally, but if not, a
40 cable connecting the analogue out to the analogue in should work.

Replies

Subject Author
Re: [gentoo-user] [OT] ffmpeg video+audio capture question Mick <michaelkintzios@×××××.com>