update(unitproc:bkvideo2webm):Rename, add example

diff --git a/unitproc/bkvideo2webm b/unitproc/bkvideo2webm
new file mode 100755 (executable)
index 0000000..41e9e29
--- /dev/null
+++ b/unitproc/bkvideo2webm
@@ -0,0 +1,19 @@
+#/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";