[Cin] offtopic: Digitize and record Video with A/D USB adapters

[Dominique Michel]

Le Mon, 11 Oct 2021 18:41:35 +0200,
"Terje J. Hanssen via Cin" <cin at lists.cinelerra-gg.org> a écrit :

> Mat and all
> 
> I take a follow-up included below:
> 
> Den 25.09.2021 20:47, skrev mnieuw--- via Cin:
> > Hi Terje,
> > I have used a cheap chinese USB video grabber to digitise VHS. But I
> > cannot remember the type.
> > I used VLC, which worked fine, but OBS should also work. I had
> > loaned the grabber, and have not tested if Cinelerra-GG could use
> > it directly. I cannot remember if video and audio showed up as two
> > different devices or not. If the audio is not a separate device,
> > then I doubt Audacity can record with it.

Hi,
On linux, you can use mencoder to grab audio + video and specify
any video input and output file and format you want to use. It is much
more easier to use than ffmpeg. Something like:

DSVID="/dev/video0"
NORM="PAL-BG"
SVID="2" # the input on the video device
ALSA_SVID="hw.1" # the ALSA card
RATE="48000" # [Hz] same than the sound card for best quality
WIDTH="634" # must be divisible by 16
HEIGHT="472" # must be divisible by 16
VRATE="4500" # [kbits] between 4 (small file) and 16000 (big file)
CROPED_WIDTH="628" # must be divisible by 16 or 4
CROPED_HEIGHT="448" # must be divisible by 16 or 4
CROPED_X="6"
CROPED_Y="16"
F_SV_REC="/home/dom/movie.avi"

mencoder tv:// -tv
driver=v4l2:device=$DSVID:norm=$NORM:input=$SVID:alsa:adevice=$ALSA_SVID:audiorate=$RATE:width=$WIDTH:height=$HEIGHT
-mc 0 -noskip -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=$VRATE -vf
crop=$CROPED_WIDTH:$CROPED_HEIGHT:$CROPED_X:$CROPED_Y,pp=lb -oac
mp3lame -lameopts cbr:br=64 -o $F_SV_REC"

For the video quality of VHS, if the player or the video camera have a
s-video output, and the video card a s-video input, the final record will
be better than with "standard" VHS quality. 

Cheers,
Dominique