#/bin/bash
# Desc: Convert video file to webm
# Usage: bkvideo2webm.sh [ file ]
# Example:
#     $ for file in ./*; do bkvideo2webm "$file"; done;
# Ref/Attrib: Geert Van Pamel, original author; date accessed: 2021-06-12; url: https://commons.wikimedia.org/wiki/Help:Converting_video
# Version 0.1.2
# Depends: ffmpeg version 4.1.6-1 (see https://tracker.debian.org/pkg/ffmpeg ) 

# Parameters:
#  P1: input file name

if [[ -z "$1" ]]; then echo "Input file missing"; exit; fi;

input="$1";
output=$(basename "$1").webm

ffmpeg -i "$input" -c:v libvpx-vp9 -b:v 0 -crf 30 -pass 1 -row-mt 1 -an -f webm -y /dev/null;
ffmpeg -i "$input" -c:v libvpx-vp9 -b:v 0 -crf 30 -pass 2 -row-mt 1 -c:a libopus "$output";