pub_multi_track

#!/bin/bash
set -euo pipefail

# Change directory to the root of the project
cd "$(dirname "$0")/.."

# Download the Big Buck Bunny video if it doesn't exist
if [ ! -f dev/bbb.fmp4 ]; then
	if [ ! -f dev/bbb.mp4 ]; then
		echo "Downloading ya boye Big Buck Bunny..."
		wget http://commondatastorage.googleapis.com/gtv-videos-bucket/sample/BigBuckBunny.mp4 -O dev/bbb.mp4
	fi

	echo "Converting to a (properly) fragmented MP4..."
	ffmpeg -i dev/bbb.mp4 \
		-c copy \
		-f mp4 -movflags cmaf+separate_moof+delay_moov+skip_trailer+frag_every_frame \
		dev/bbb.fmp4
fi

# Use debug logging by default
export RUST_LOG="${RUST_LOG:-debug}"

# Connect to localhost by default.
HOST="${HOST:-localhost}"
PORT="${PORT:-4443}"
ADDR="${ADDR:-$HOST:$PORT}"
SCHEME="${SCHEME:-https}"

# Use the name "bbb" for the broadcast.
NAME="${NAME:-bbb}"

# Combine the host into a URL.
URL="${URL:-"$SCHEME://$ADDR"}"

# Default to a source video
INPUT="${INPUT:-dev/bbb.fmp4}"

# Print out the watch URL
echo "Watch URL: https://quic.video/watch/$NAME?server=$ADDR"

# ==== Commence of building config paramters for mutlitrack FFmpeg CLI ====

# Regex pattern for the video related arg: "<resolution>:<bitrate>:<fps>"
pattern="^[0-9]+x[0-9]+:[0-9]+K:[0-9]+$"

#Default values for video resolutions and bitrates, defaults to be used , if no arguments are passed
default_res1_bitrate1_fps1="1920x1080:6000K:60"
default_res2_bitrate2_fps2="1280x720:5000K:30"
default_res3_bitrate3_fps3="640x480:4000K:25"

# To be passed to cargo
additional_args=""

# check if first arguments are for video
check_arg_format() {
	[[ $1 =~ $pattern ]]
}

if [ "$#" -gt 0 ]; then
	for i in {1..3}; do
		if [ "$#" -gt 0 ] && check_arg_format "$1"; then
			case $i in
				1) default_res1_bitrate1_fps1="$1" ;;
				2) default_res2_bitrate2_fps2="$1" ;;
				3) default_res3_bitrate3_fps3="$1" ;;
			esac
			shift
		else
			additional_args="$@"
			break
		fi
	done
	[ "$#" -gt 0 ] && additional_args="$@"
fi

#Common param
videofps=25
gopduration=1

# Extract resolution and bitrate from the first argument and calculate other related parameters
video_res1="${default_res1_bitrate1_fps1%%:*}"		# Extracts the resolution
temp="${default_res1_bitrate1_fps1#*:}"			# Removes resolution to extract bitrate & fps
video_bitrate1="${temp%:*}"				# Extracts the bitrate by removing FPS
video_fps1="${temp##*:}"				# Extracts the FPS
keyframeinterval1=$((gopduration * video_fps1))	# GOP duration times video fps
maxrate1=$(( ${video_bitrate1%K} + (${video_bitrate1%K} / 10) ))K	# 10% higher than video bitrate
minrate1=$(( ${video_bitrate1%K} - (${video_bitrate1%K} / 10) ))K	# 10% lower than video bitrate
bufsize1=$((2 * ${video_bitrate1%K}))K			# 2 times video bitrate
gopsize1=$((gopduration * video_fps1))			# GOP duration times video fps

# Extract resolution and bitrate from the second argument and calculate other related parameters
video_res2="${default_res2_bitrate2_fps2%%:*}"
temp="${default_res2_bitrate2_fps2#*:}"
video_bitrate2="${temp%:*}"
video_fps2="${temp##*:}"
keyframeinterval2=$((gopduration * video_fps2))
maxrate2=$(( ${video_bitrate2%K} + (${video_bitrate2%K} / 10) ))K
minrate2=$(( ${video_bitrate2%K} - (${video_bitrate2%K} / 10) ))K
bufsize2=$((2 * ${video_bitrate2%K}))K
gopsize2=$((gopduration * video_fps2))

# Extract resolution and bitrate from the third argument and calculate other related parameters
video_res3="${default_res3_bitrate3_fps3%%:*}"
temp="${default_res3_bitrate3_fps3#*:}"
video_bitrate3="${temp%:*}"
video_fps3="${temp##*:}"
keyframeinterval3=$((gopduration * video_fps3))
maxrate3=$(( ${video_bitrate3%K} + (${video_bitrate3%K} / 10) ))K
minrate3=$(( ${video_bitrate3%K} - (${video_bitrate3%K} / 10) ))K
bufsize3=$((2 * ${video_bitrate3%K}))K
gopsize3=$((gopduration * video_fps3))
		
#Watermark the video resolution and bitrate for ease of identification of the track
res1_text=$(echo "$video_res1" | sed 's/x.*//')p
res2_text=$(echo "$video_res2" | sed 's/x.*//')p
res3_text=$(echo "$video_res3" | sed 's/x.*//')p

#Watermark/overlay display settings
drawtext_base="fontsize=30:box=1:boxcolor=black@0.75:fontcolor=white"
drawtext_time="${drawtext_base}:text='%{localtime}.%{eif\\:1M*t-1K*trunc(t*1K)\\:d}'"

# Define common video filter settings
common_settings="settb=AVTB,setpts='trunc(PTS/1K)*1K+st(1,trunc(RTCTIME/1K))-1K*trunc(ld(1)/1K)'"

# Build the filter complex for each video stream

scaling_alg=bicubic

filter_v0="
	[v0]fps=${video_fps1},
	${common_settings},
	drawtext=${drawtext_time},
	drawtext=text='${res1_text}-${video_bitrate1}':x=w-tw:y=h-th:${drawtext_base},
	scale=${video_res1}:flags=${scaling_alg}[v0final]"

filter_v1="
	[v1]fps=${video_fps2},
	${common_settings},
	drawtext=${drawtext_time},
	drawtext=text='${res2_text}-${video_bitrate2}':x=w-tw:y=h-th:${drawtext_base},
	scale=${video_res2}:flags=${scaling_alg}[v1final]"

filter_v2="
	[v2]fps=${video_fps3},
	${common_settings},
	drawtext=${drawtext_time},
	drawtext=text='${res3_text}-${video_bitrate3}':x=w-tw:y=h-th:${drawtext_base},
	scale=${video_res3}:flags=${scaling_alg}[v2final]"

filter_complex="${filter_v0}; ${filter_v1}; ${filter_v2}"

# Build the codec settings for each video stream

COMMON_X264_PARAMS="libx264 -profile:v high -preset veryfast -tune zerolatency"

codec_v0="-c:v:0 $COMMON_X264_PARAMS \
	-b:v ${video_bitrate1} \
	-maxrate ${maxrate1} \
	-minrate ${minrate1} \
	-bufsize ${bufsize1} \
	-keyint_min ${keyframeinterval1} \
	-g ${gopsize1} \
	-x264-params \"keyint=${keyframeinterval1}:scenecut=0:bframes=0\""

codec_v1="-c:v:1 $COMMON_X264_PARAMS \
	-b:v ${video_bitrate2} \
	-maxrate ${maxrate2} \
	-minrate ${minrate2} \
	-bufsize ${bufsize2} \
	-keyint_min ${keyframeinterval2} \
	-g ${gopsize2} \
	-x264-params \"keyint=${keyframeinterval2}:scenecut=0:bframes=0\""

codec_v2="-c:v:2 $COMMON_X264_PARAMS \
	-b:v ${video_bitrate3} \
	-maxrate ${maxrate3} \
	-minrate ${minrate3} \
	-bufsize ${bufsize3} \
	-keyint_min ${keyframeinterval3} \
	-g ${gopsize3} \
	-x264-params \"keyint=${keyframeinterval3}:scenecut=0:bframes=0\""

# ==== Done building config paramters for mutlitrack FFmpeg CLI ====

# Run ffmpeg and pipe the output to moq-pub

#Creates 3 video tracks simulating realtime live stream and an audio track with server clock
#overlayed at top left corner and video resolution-bitrate overlayed at bottom right corner

ffmpeg -hide_banner -v quiet \
	-stream_loop -1 -re \
	-i "$INPUT" -r ${videofps} \
	-filter_complex "[0:v]split=3[v0][v1][v2]; ${filter_complex}" \
	-map "[v0final]" -map "[v1final]" -map "[v2final]" -map 0:a \
	$codec_v0 \
	$codec_v1 \
	$codec_v2 \
	-c:a copy \
	-f mp4 -movflags cmaf+separate_moof+delay_moov+skip_trailer+frag_every_frame \
	- | cargo run --bin moq-pub -- --name "$NAME" "$URL" $additional_args