Simple shell script to configure alsa the record from capture card

rec_vhs.sh

#!/bin/bash

function set_alsa {
    #Unmute Line
    amixer sset Line 100 -q
    amixer sset Line unmute -q

    #Mute PCM record
    amixer sset PCM Capture 0 -q
    
    #Set capture for Analog Mix
    amixer sset 'Analog Mix' CAPTURE 100 -q

    #Set analog mix to 100
    amixer sset 'Analog Mix' 100 -q
    
    echo "Alsa is set and ready for the hard work..."
}

if [ -z $1 ]; then
    echo "Usage: rec_vhs.mpg filename.mpg"
    exit
elif [[ $1 != *.mpg ]]; then
    echo "Must be an mpg file!"
    exit
fi

set_alsa

mencoder -tv norm=NTSC:driver=v4l2:width=704:height=480:input=1:amode=1 tv:// -oac lavc -ovc lavc -of mpeg \
-mpegopts format=dvd -vf pp=lb/ha/va/dr,hqdn3d,harddup \
-srate 48000 -af lavcresample=48000 -lavcopts vcodec=mpeg2video:vrc_buf_size=1500:vrc_maxrate=8000:vbitrate=7000:keyint=15:acodec=mp2:abitrate=192:aspect=4/3 \
-quiet -o $1


echo "Done recording" $1