#!/bin/sh

set -e

AINPUT=hw:0
VINPUT=/dev/fw1
LOGO=../../content/icon_small.png

HOST=${1:-morla}
if [ "$HOST" = "$(hostname --short)" ]; then
	IP=127.0.0.1
else
	IP=$(host "$HOST" | grep -Po 'address \K\S+')
fi

FIRSTPORT=${2:-5002} # even number - next 3 ports used too

ACHANNELS=2
AFRAMERATE=48000
ABITRATE=32000

HEIGHT=360
VBITRATE=256000

# based on http://www.webmproject.org/docs/encoder-parameters/#real-time-cbr-encoding-and-streaming
# + scale+watermark trick based on http://stackoverflow.com/a/10937357
# + Add 1s latency (deadline)
# + Use same RTP payload types as GStreamer
ffmpeg -hide_banner -threads auto -re \
 -f alsa -sample_rate "$AFRAMERATE" -channels "$ACHANNELS" -thread_queue_size 1024 -i "$AINPUT" \
 -f libdc1394 -video_size 640x480 -framerate 15 -thread_queue_size 256 -i "$VINPUT" \
 -i "$LOGO" \
 -filter_complex \
 "[1:v]scale=-1:$HEIGHT[bg];
  [bg][2:v]overlay=main_w-overlay_w-20:main_h-overlay_h-20[v]" \
 -map '0:a' \
 -codec:a libopus -ac "$ACHANNELS" -ar "$AFRAMERATE" -b:a "$ABITRATE" \
 -f rtp -payload_type 111 "rtp://$IP:$FIRSTPORT?pkt_size=1200" \
 -map '[v]' \
 -pix_fmt yuv420p \
 -codec:v vp8 -quality realtime -deadline 1000000 -cpu-used 15 \
 -b:v "$VBITRATE" -minrate "$VBITRATE" -maxrate "$VBITRATE" \
 -undershoot-pct 95 -bufsize $((6000*VBITRATE/1000)) -rc_init_occupancy $((4000*VBITRATE/1000)) \
 -max-intra-rate 0 \
 -qmin 4 -qmax 56 \
 -f rtp -payload_type 100 "rtp://$IP:$((FIRSTPORT+2))?pkt_size=1200"