Using ffmpeg to split video files by size

#!/bin/bash
# Short script to split videos by filesize using ffmpeg by LukeLR
 
if [ $# -ne 3 ]; then
    echo 'Illegal number of parameters. Needs 3 parameters:'
    echo 'Usage:'
    echo './split-video.sh FILE SIZELIMIT "FFMPEG_ARGS'
    echo 
    echo 'Parameters:'
    echo '    - FILE:        Name of the video file to split'
    echo '    - SIZELIMIT:   Maximum file size of each part (in bytes)'
    echo '    - FFMPEG_ARGS: Additional arguments to pass to each ffmpeg-call'
    echo '                   (video format and quality options etc.)'
    exit 1
fi
 
FILE="$1"
SIZELIMIT="$2"
FFMPEG_ARGS="$3"
 
# Duration of the source video
DURATION=$(ffprobe -i "$FILE" -show_entries format=duration -v quiet -of default=noprint_wrappers=1:nokey=1|cut -d. -f1)
 
# Duration that has been encoded so far
CUR_DURATION=0
 
# Filename of the source video (without extension)
BASENAME="${FILE%.*}"
 
# Extension for the video parts
#EXTENSION="${FILE##*.}"
EXTENSION="mp4"
 
# Number of the current video part
i=1
 
# Filename of the next video part
NEXTFILENAME="$BASENAME-$i.$EXTENSION"
 
echo "Duration of source video: $DURATION"
 
# Until the duration of all partial videos has reached the duration of the source video
while [[ $CUR_DURATION -lt $DURATION ]]; do
    # Encode next part
    echo ffmpeg -i "$FILE" -ss "$CUR_DURATION" -fs "$SIZELIMIT" $FFMPEG_ARGS "$NEXTFILENAME"
    ffmpeg -ss "$CUR_DURATION" -i "$FILE" -fs "$SIZELIMIT" $FFMPEG_ARGS "$NEXTFILENAME"
 
    # Duration of the new part
    NEW_DURATION=$(ffprobe -i "$NEXTFILENAME" -show_entries format=duration -v quiet -of default=noprint_wrappers=1:nokey=1|cut -d. -f1)
 
    # Total duration encoded so far
    CUR_DURATION=$((CUR_DURATION + NEW_DURATION))
 
    i=$((i + 1))
 
    echo "Duration of $NEXTFILENAME: $NEW_DURATION"
    echo "Part No. $i starts at $CUR_DURATION"
 
    NEXTFILENAME="$BASENAME-$i.$EXTENSION"
done