Livestreaming Script

chika.sh

#!/bin/sh

# Usage: $ sh chika.sh -v TARGET_PATH [-i] [-t START_TIME] [-e EPISODE_NO] [-a AUDIO_TRACK] [-s SUBTITLE_TRACK] [-f]
# -v TARGET_PATH: Direct path to target file or directory to stream from.
# -i: Provide info about the file.
# -d: Run in debug mode, which prevents the stream from running and the playlist from being deleted.
# -t START_TIME: Start from specified time (as HH:MM:SS.MS).
# -e EPISODE_NO: Start from an episode number when a directory is provided.
# -a AUDIO_TRACK: Specify an audio track to use.
# -s SUBTITLE_TRACK: Use subs embedded in the video file. Optionally specify which subtitle track to use.
# -f: Force subtitle style.
#
# If TARGET_PATH is a directory, all files in the directory will be played.
#
# Note: Using -t and -s together will not work.
#       The video will start at the specified time, but the subs will always burn in at 0 and will be offset.

# Specify streaming settings.
AUDIO_BITRATE=320k
VIDEO_BITRATE=3000k
KEYFRAME_INTERVAL=2
B_FRAMES=3
URL="rtmp://<stream url goes here>"

# Specify optional arguments defaults and set them if they're provided via command line.
TARGET_PATH=null
DEBUG_MODE=false
START_TIME="00:00:00.0"
EPISODE_NO=1
AUDIO_TRACK=0
USE_SUBTITLE_TRACK=false
SUBTITLE_TRACK=0
FORCE_SUBTITLE_STYLE=false
while :; do
    case $1 in
        -v) TARGET_PATH="$2"; shift;;
        -i) if [ -f $TARGET_PATH ]; then ffmpeg -i $TARGET_PATH -hide_banner; exit; else echo "Specified path was not a file."; exit; fi;;
        -d) DEBUG_MODE=true;;
        -t) START_TIME=$2; shift;;
        -e) EPISODE_NO=$2; shift;;
        -a) AUDIO_TRACK=$2; shift;;
        -s) USE_SUBTITLE_TRACK=true;
            if [ $2 ] && [[ "$2" != \-* ]]; then SUBTITLE_TRACK=$2; shift; fi;;
        -f) FORCE_SUBTITLE_STYLE=true;;
        --) shift; break;;
        -?*) printf 'Unknown option (ignored): %s\n' "$1" >&2;;
        *) break
    esac
    shift
done

# Create a playlist based on if a file or directory was provided, and starts on the provided starting episode.
find "$TARGET_PATH" -type f \( -iname \*.mp4 -o -iname \*.mkv \) | sort > chaika_playlist_temp.txt
if [[ $EPISODE_NO -gt 1 ]]; then
    tail -n +$EPISODE_NO chaika_playlist_temp.txt > chaika_playlist.txt
    rm chaika_playlist_temp.txt
else
    mv chaika_playlist_temp.txt chaika_playlist.txt
fi

# Process each file on the playlist in sequence.
while read VIDEO_FILE; do
    # Specify the subtitle video filter.
    VIDEO_FILTER=null
    if [ $USE_SUBTITLE_TRACK == true ]; then VIDEO_FILTER="subtitles='$VIDEO_FILE':si=$SUBTITLE_TRACK"; fi
    if [ $FORCE_SUBTITLE_STYLE == true ]; then VIDEO_FILTER="$VIDEO_FILTER:force_style='Fontsize=24,PrimaryColour=&Hffffff&'"; fi

    # Get the framerate and keyframerate from the video file.
    VIDEO_FILE_NAME=`basename "$VIDEO_FILE"`
    FRAMERATE=`ffmpeg -i "$VIDEO_FILE" 2>&1 | sed -n "s/.*, \(.*\) tbr.*/\1/p"`
    KEYFRAMERATE=`bc <<< "$FRAMERATE * $KEYFRAME_INTERVAL"`

    # Provide info about the stream that's about to start.
    echo ""
    echo "Streaming $VIDEO_FILE_NAME."
    ffmpeg -i "$VIDEO_FILE" 2>&1 | grep "Duration"
    if [ $START_TIME != "00:00:00.0" ]; then echo "  Playing from $START_TIME."; fi
    if [ $AUDIO_TRACK != 0 ]; then echo "  Using audio track #$AUDIO_TRACK."; fi
    if [ $USE_SUBTITLE_TRACK == true ]; then echo "  Using subtitle track #$SUBTITLE_TRACK from video file."; fi
    echo ""

    # Start the stream.
    if [ $DEBUG_MODE = false ]; then
        ffmpeg \
            -hide_banner \
            -loglevel error \
            -stats \
            -nostdin \
            -re \
            -ss $START_TIME \
            -i "$VIDEO_FILE" \
            -c:v h264_nvenc \
            -pix_fmt yuv420p \
            -vf "$VIDEO_FILTER" \
            -preset default \
            -profile:v high \
            -threads:v 2 \
            -threads:a 8 \
            -filter_threads 2 \
            -f alsa \
            -bsf:a aac_adtstoasc \
            -c:a aac \
            -ac 2 \
            -b:a $AUDIO_BITRATE \
            -b:v $VIDEO_BITRATE \
            -minrate:v $VIDEO_BITRATE \
            -maxrate:v $VIDEO_BITRATE \
            -bufsize:v $VIDEO_BITRATE \
            -qp:v 19 \
            -rc:v cbr_ld_hq \
            -level:v auto \
            -r:v $FRAMERATE \
            -g:v $KEYFRAMERATE \
            -bf:v $B_FRAMES \
            -map 0:v \
            -map 0:a:$AUDIO_TRACK \
            -f flv $URL
    fi
done < chaika_playlist.txt

# Delete the playlist.
if [ $DEBUG_MODE = false ]; then rm chaika_playlist.txt; fi