stack-tbcs

#!/bin/bash -ex
# Read (and dropout-correct) several .tbc files representing the same video,
# and combine them using ffmpeg.
#
# Output is in .tbc format to stdout, for piping into ld-chroma-decoder using
# the JSON file from one of the inputs.

# XXX Assumes 3 inputs
if [ "$#" != 3 ]; then
	echo "Must supply three input .tbc files"
	exit 1
fi
in1="$1"
in2="$2"
in3="$3"

# XXX Assumes PAL
format="-f rawvideo -pix_fmt gray16 -s 1135x626 -r 25"

# XXX Option for this
mode="docmedian"

case "$mode" in
median)
	# Median of three copies (does a pretty good job of removing dropouts by itself)
	ffmpeg \
		$format -i "$in1" \
		$format -i "$in2" \
		$format -i "$in3" \
		-filter_complex xmedian=inputs=3 \
		$format -
	;;
docmedian)
	# Median of three dropout-corrected copies
	ffmpeg \
		$format -i <(ld-dropout-correct --overcorrect --output-json /dev/null "$in1" -) \
		$format -i <(ld-dropout-correct --overcorrect --output-json /dev/null "$in2" -) \
		$format -i <(ld-dropout-correct --overcorrect --output-json /dev/null "$in3" -) \
		-filter_complex xmedian=inputs=3 \
		$format -
	;;
mean)
	# Mean of three copies
	# XXX docs for mix call the option "nb_inputs"
	ffmpeg \
		$format -i "$in1" \
		$format -i "$in2" \
		$format -i "$in3" \
		-filter_complex mix=inputs=3 \
		$format -
	;;
docmean)
	# Mean of three dropout-corrected copies
	ffmpeg \
		$format -i <(ld-dropout-correct --overcorrect --output-json /dev/null "$in1" -) \
		$format -i <(ld-dropout-correct --overcorrect --output-json /dev/null "$in2" -) \
		$format -i <(ld-dropout-correct --overcorrect --output-json /dev/null "$in3" -) \
		-filter_complex mix=inputs=3 \
		$format -
	;;
esac