#!/bin/sh

# Send RTP video and audio streams

set -e
RECIP=${RECIP:-$1} # destination host - default: use multicast group
VDEVICES=${2:-$(find /dev -maxdepth 1 -type c -name 'video*' | sort)}
#ADEVICES=${3:-$(arecord -L | grep -Po '^hw:\S+')}
#ADEVICES=${3:-$(arecord -L | grep -Pom1 '^hw:\S+')}
ADEVICES=${3:-} # FIXME: Detect/blacklist and skip faulty devices
VFORMAT=${VFORMAT:-$4} # H264 VP8 RAW - default: RAW
AFORMAT=${AFORMAT:-$5} # AMR OPUS RAW - default: RAW
set -u

# set multicast groups (also for recorder host) if camera host is wildcard
[ -n "$RECIP" ] || RECMIP=239.255.0.1
[ -n "$RECIP" ] || CAMMIP=239.255.0.2
RECHOST="${RECIP:+host=$RECIP}${RECMIP:+host=$RECMIP auto-multicast=true}"
CAMHOST="${CAMMIP:+address=$CAMMIP auto-multicast=true}"

HEIGHT=240
FRAMERATE=25
AUDIORATE=48000

VCAPS=video/x-raw,height="$HEIGHT"
ACAPS=audio/x-raw,rate="$AUDIORATE",channels=2,depth=16

# * http://stackoverflow.com/a/42237307
ABUFFERS=20000

# * force threads using queues - see http://stackoverflow.com/a/30738533
# * generous queue sizes inspired by https://wiki.xiph.org/GST_cookbook
QUEUE=" queue max-size-bytes=100000000 max-size-time=0"

case "$VFORMAT" in
 H264)
  # * let x264 use low-latency sliced-threads (i.e. don't disable treads)
  VENC="x264enc speed-preset=ultrafast tune=zerolatency bitrate=800 byte-stream=true key-int-max=15 intra-refresh=true option-string=\"slice-max-size=8192:vbv-maxrate=80:vbv-bufsize=10\" ! video/x-h264,profile=baseline ! $QUEUE ! rtph264pay"
  ;;
 VP8)
  VENC="vp8enc cpu-used=10 threads=2 deadline=10000 ! video/x-vp8 ! $QUEUE ! rtpvp8pay"
  ;;
 RAW|'')
  VENC="rtpvrawpay"
  ;;
 *)
  echo "ERROR: Unsupported video format: \"$VFORMAT\""
  exit 1
  ;;
esac

case "$AFORMAT" in
 AMR)
  AENC="amrnbenc ! $QUEUE ! rtpamrpay"
  ;;
 OPUS)
  AENC="opusenc ! $QUEUE ! rtpopuspay"
  ;;
 RAW|'')
  AENC="rtpL16pay"
  ;;
 *)
  echo "ERROR: Unsupported audio format: \"$AFORMAT\""
  exit 1
  ;;
esac

stream() {
 ID=$1
 SRC=$2
 echo \
 $SRC \
  ! "rtpbin.send_rtp_sink_$ID" \
 rtpbin."send_rtp_src_$ID" ! queue \
  ! udpsink name="rtp_sink_$ID" port=$((5000+ID-1)) $RECHOST \
 rtpbin.send_rtcp_src_$ID \
  ! udpsink name="rtcp_sink_$ID" port=$((5010+ID-1)) $RECHOST sync=false async=false \
 udpsrc name="rtp_src_$ID" port=$((5020+ID-1)) $CAMHOST \
  ! rtpbin."recv_rtcp_sink_$ID"
}

gst-launch-1.0 -v \
 rtpbin name=rtpbin \
 $(n=0;\
  for dev in $VDEVICES; do n=$((n+1)); stream "$n" "v4l2src device=$dev ! $QUEUE ! videoconvert ! $VCAPS ! $QUEUE ! $VENC ! $QUEUE"; done;\
  for dev in $ADEVICES; do n=$((n+1)); stream "$n" "alsasrc device=$dev buffer-time=$ABUFFERS ! $QUEUE ! audioconvert ! $QUEUE ! $AENC ! $QUEUE"; done;\
 )

set -e