Question / Help Unable to record audio

[balanga]

I started a thread in the Windows section about being unable to record Video, which apparently is because my capture device is not compatible with OBS on Windows, however I can record Audio.

After installing Ubuntu and OBS I find that capturing Video is straightforward, but Audio is not getting recorded. I assume this is because I haven't yet figured out how to record it...

My aim is simply to digitise some VHS tapes. Can anyone suggest how to set things up for capturing Audio?

 

[balanga]

Just thought I'd document what I do when trying to digitise a tape...

Switch on VCR
Connect capture device to laptop - two phono plugs to VCR (white and yellow), USB to laptop
Start up OBS
Add Video Capture Device (V4L2) to sources
Device identified as EM2860/SAA711X Reference Design (usb-0000:00:1d.0-1.5)
Change Input from S-Video to Composite
OK
Display frame appears
Add Audio Capture Device (ALSA) to sources
Change Device from Default USB Device 0xeb1a:0x2861, USB Audio
Audio Capture Device (ALSA) entry appears in Mixer window
Press Play on VCR
Video image appears
No movement in mixer window

I guess some settings need to be modified but can't figure out which...

 

[balanga]

Log file:-

12:30:51.558: CPU Name: Intel(R) Core(TM) i3-3120M CPU @ 2.50GHz
12:30:51.558: CPU Speed: 2362.292MHz
12:30:51.558: Physical Cores: 2, Logical Cores: 4
12:30:51.558: Physical Memory: 3645MB Total, 832MB Free
12:30:51.558: Kernel Version: Linux 4.18.0-21-generic
12:30:51.558: Distribution: "Ubuntu" "18.04"
12:30:51.559: Window System: X11.0, Vendor: The X.Org Foundation, Version: 1.20.1
12:30:51.559: Portable mode: false
12:30:51.620: OBS 23.1.0 (linux)
12:30:51.620: ---------------------------------
12:30:51.656: ---------------------------------
12:30:51.657: audio settings reset:
12:30:51.657:     samples per sec: 44100
12:30:51.657:     speakers:        1
12:30:51.677: ---------------------------------
12:30:51.677: Initializing OpenGL...
12:30:51.711: Loading up OpenGL on adapter Intel Open Source Technology Center Mesa DRI Intel(R) Ivybridge Mobile
12:30:51.711: OpenGL loaded successfully, version 4.2 (Core Profile) Mesa 18.2.2, shading language 4.20
12:30:51.752: ---------------------------------
12:30:51.752: video settings reset:
12:30:51.752:     base resolution:   1366x768
12:30:51.752:     output resolution: 908x512
12:30:51.752:     downscale filter:  Bicubic
12:30:51.752:     fps:               30/1
12:30:51.752:     format:            NV12
12:30:51.752:     YUV mode:          601/Partial
12:30:51.753: NV12 texture support not available
12:30:51.758: Audio monitoring device:
12:30:51.758:     name: Default
12:30:51.758:     id: default
12:30:51.758: ---------------------------------
12:30:51.760: Failed to load 'en-US' text for module: 'decklink-ouput-ui.so'
12:30:51.895: No blackmagic support
12:30:51.934: os_dlopen(libnvidia-encode.so.1->libnvidia-encode.so.1): libnvidia-encode.so.1: cannot open shared object file: No such file or directory
12:30:51.934:
12:30:51.934: FFMPEG VAAPI supported
12:30:51.950: VLC found, VLC video source enabled
12:30:51.951: ---------------------------------
12:30:51.951:   Loaded Modules:
12:30:51.951:     vlc-video.so
12:30:51.951:     text-freetype2.so
12:30:51.951:     rtmp-services.so
12:30:51.951:     obs-x264.so
12:30:51.951:     obs-transitions.so
12:30:51.951:     obs-outputs.so
12:30:51.951:     obs-libfdk.so
12:30:51.951:     obs-filters.so
12:30:51.951:     obs-ffmpeg.so
12:30:51.951:     linux-v4l2.so
12:30:51.951:     linux-pulseaudio.so
12:30:51.951:     linux-jack.so
12:30:51.951:     linux-decklink.so
12:30:51.951:     linux-capture.so
12:30:51.951:     linux-alsa.so
12:30:51.951:     image-source.so
12:30:51.951:     frontend-tools.so
12:30:51.951:     decklink-ouput-ui.so
12:30:51.951: ---------------------------------
12:30:51.951: ==== Startup complete ===============================================
12:30:51.951: Service '' not found
12:30:51.953: All scene data cleared
12:30:51.953: ------------------------------------------------
12:30:51.956: pulse-input: Server name: 'pulseaudio 11.1'
12:30:51.957: pulse-input: Audio format: s16le, 44100 Hz, 2 channels
12:30:51.957: pulse-input: Started recording from 'alsa_output.pci-0000_00_1b.0.analog-stereo.monitor'
12:30:51.958: pulse-input: Server name: 'pulseaudio 11.1'
12:30:51.959: pulse-input: Audio format: s16le, 44100 Hz, 2 channels
12:30:51.959: pulse-input: Started recording from 'alsa_input.usb-eb1a_2861-01.analog-stereo'
12:30:51.969: alsa-input: Failed to open 'front:CARD=U0xeb1a0x2861,DEV=0': Device or resource busy
12:30:51.970: v4l2-input: Start capture from /dev/video0
12:30:52.466: adding 23 milliseconds of audio buffering, total audio buffering is now 23 milliseconds (source: Desktop Audio)
12:30:52.466:
12:30:52.853: v4l2-input: Input: 1
12:30:52.970: alsa-input: Failed to open 'front:CARD=U0xeb1a0x2861,DEV=0': Device or resource busy
12:30:53.165: v4l2-input: Resolution: 720x576
12:30:53.165: v4l2-input: Pixelformat: VYUY
12:30:53.166: v4l2-input: Linesize: 1440 Bytes
12:30:53.166: v4l2-input: Framerate: 25,00 fps
12:30:53.167: Switched to scene 'Scene'
12:30:53.168: ------------------------------------------------
12:30:53.168: Loaded scenes:
12:30:53.168: - scene 'Scene':
12:30:53.168:     - source: 'Video Capture Device (V4L2)' (v4l2_input)
12:30:53.168:     - source: 'Audio Capture Device (ALSA)' (alsa_input_capture)
12:30:53.168: ------------------------------------------------
12:30:53.579: adding 23 milliseconds of audio buffering, total audio buffering is now 46 milliseconds (source: Mic/Aux)
12:30:53.579:
12:30:54.948: adding 23 milliseconds of audio buffering, total audio buffering is now 69 milliseconds (source: Mic/Aux)
12:30:54.948:
12:30:54.972: alsa-input: Failed to open 'front:CARD=U0xeb1a0x2861,DEV=0': Device or resource busy
12:30:56.526: adding 23 milliseconds of audio buffering, total audio buffering is now 92 milliseconds (source: Mic/Aux)
12:30:56.526:
12:30:57.973: alsa-input: Failed to open 'front:CARD=U0xeb1a0x2861,DEV=0': Device or resource busy
12:31:01.974: alsa-input: Failed to open 'front:CARD=U0xeb1a0x2861,DEV=0': Device or resource busy

Don't know why the Audio Capture Card is 'busy'......

Any suggestions?

 

[Narcogen]

Device drivers are often exclusive. "busy" would indicate another application is using it.

In Windows, audio devices can be set to be non-exclusive. Not sure about ALSA devices; for my Linux setup and my capture device, all 3 versions have pretty much worked the same way-- audio and video from the same capture device over USB. Getting other audio sources in was the problem in Linux.

 

[obsbxf4]

I was getting the device busy message too and it seems Pulseaudio was the culprit. 'pactl exit' caused the busy messages to cease. This was on Debian linux.