Updated capture card script to have very small delay

remedios/capturecard

@@ -5,42 +5,32 @@
 # -- Siina, 2020.11.09
 #
 # Requirements:
-# - alsa-utils
 # - libv4l (brought in by USE=v4l)
 # - mpv
-#
-# Tools I used to figure this shit out
-# - arecord, aplay
-# - ffmpeg
-# - lspci
-# - Lots of searching through ancient fragments of the 'net
-#
-# TODO:
-# - Capture the exact PIDs of the launched mpv / alsaloop to prevent 
-#   shutting down any other loops / mpv that happen to be open
 
+## 0 - Find input and output sources with pactl
+input="alsa_input.usb-AVerMedia_AVerMedia_USB_Device_52030300003520-02.iec958-stereo"
+output="alsa_output.pci-0000_0b_00.4.analog-stereo"
+
+## 1 - Configure video
 # Set our device to 1080p otherwise it defaults to 480p
 v4l2-ctl --set-fmt-video=width=1920,height=1080
 
+## 2 - Launch viewer
 # Connect to capture card and display captured images immediately
 # Send to background so we can initiate the loop below
 mpv --title="Capture Card"  av://v4l2:/dev/video0 --profile=low-latency --untimed &
 
-# Run a loop for the capture card digital audio to be sent to my desktop audio
-while :
-do
-	alsaloop -C hw:2,0 -P hw:1,0 &
-	if [[ $(pgrep -f alsaloop) -gt 0 ]]; then
-		break
-	fi
-done
+## 3 - Connect audio, send to background for loop
+pacat -r --latency-msec=1 -d $input | pacat -p --latency-msec=1 -d $output &
 
+## 4 - Cleanup
 # Watch for mpv to exit
 while pgrep -f mpv >/dev/null; do
 	sleep 3
 	continue
 done
 
-# Kill the alsaloop when mpv exits, then terminate this script
-kill -9 $(pgrep -f alsaloop)
+# Kill pacat since it's not needed
+kill -9 $(pgrep -f pacat)
 exit