#!/bin/sh # FIXME: Handle audio track in main input # TODO: Handle audio as secondary input set -e ## ## defaults ## INPUT=../src/omni/show0/earth.mp4 LOGO=../../content/icon_small.png RATIO=4:3 ## ## generic functions ## # shellcheck disable=SC2048,SC2059 echo_n() { printf -- "$*" } HOST=${1:-morla} if [ "$HOST" = "$(hostname --short)" ]; then IP=127.0.0.1 else IP=$(host "$HOST" | grep -Po 'address \K\S+') fi FIRSTPORT=${2:-5002} # even number - next 3 ports used too ITERATIONS=${3-0} # endless by default HEIGHT=384 videosize() { height=$1; width_or_ratio=$2; case $width_or_ratio in *:*) num=${width_or_ratio%:*}; den=${width_or_ratio#*:}; width=$((height*num/den));; *) width=$width_or_ratio;; esac echo_n $((height*width)) } BITS=$(videosize "$HEIGHT" "$RATIO") # * bitrates and bits in parens based on https://developer.apple.com/library/content/documentation/General/Reference/HLSAuthoringSpec/Requirements.html # + bits rounded up to include nearby modulo 16 formats # + best (i.e. high-modulo) 16:9 heights: 216 288 360 432 576 720 # + best (i.e. high-modulo) 4:3 heights: 288 312 384 480 624 816 # * speeds tuned to just below 100% cpu usage for each combination on a multi-core computer # TODO: Externalize speeds to site-specific configfile if [ $BITS -le 110592 ]; then # 234p → 97344 VBITRATE=145000 SPEED_VP8=2 elif [ $BITS -le 150528 ]; then # 270p → 129600 VBITRATE=365000 SPEED_VP8=2 elif [ $BITS -le 196608 ]; then # 360p → 172800 VBITRATE=730000 SPEED_VP8=3 elif [ $BITS -le 331776 ]; then # 432p → 331776 VBITRATE=1100000 SPEED_VP8=4 elif [ $BITS -le 589824 ]; then # 540p → 518400 VBITRATE=2000000 SPEED_VP8=5 elif [ $BITS -le 921600 ]; then # 720p → 921600 VBITRATE=3000000 SPEED_VP8=15 fi encode_vp8() { bitrate=$1; speed=$2; echo_n "-codec:v vp8 -quality realtime -deadline 1000000 -cpu-used $speed \ -b:v $bitrate -minrate $bitrate -maxrate $bitrate \ -undershoot-pct 95 -bufsize $((6000*bitrate/1000)) -rc_init_occupancy $((4000*bitrate/1000)) \ -max-intra-rate 0 \ -qmin 4 -qmax 56" } # based on http://www.webmproject.org/docs/encoder-parameters/#real-time-cbr-encoding-and-streaming # + loop-in-filter trick based on http://video.stackexchange.com/a/16933 # + scale+watermark trick based on http://stackoverflow.com/a/10937357 # + scale to square pixels as needed # + Add 1s latency (deadline) # + Use same RTP payload types as GStreamer ffmpeg -hide_banner -threads auto -re \ -f lavfi -i "movie=filename=$INPUT:loop=$ITERATIONS, setpts=N/(FRAME_RATE*TB)" \ -i "$LOGO" \ -filter_complex \ "[0:v]format=pix_fmts=yuv420p,scale=iw*sar*$HEIGHT/ih:$HEIGHT,setsar=1[bg]; [bg][1:v]overlay=main_w-overlay_w-20:main_h-overlay_h-20[v]" \ -map '[v]' \ $(encode_vp8 "$VBITRATE" "$SPEED_VP8") \ -f rtp -payload_type 100 "rtp://$IP:$((FIRSTPORT+2))?pkt_size=1200"