#!/bin/bash

# blurp middle frame from video to ascii
# not using anything from singularity, needs:
# ffmpeg and jp2a (and maybe imagemagick)

# usage:
# 	middleFrame *.mp4
# with parallel:
#	find . -name "*.mp4" | parallel --gnu middleFrame {}

# tmp dir http://mywiki.wooledge.org/BashFAQ/062
tmp="/tmp/$RANDOM-$$"
trap '[ -n "$tmp" ] && rm -fr "$tmp"' EXIT
mkdir -m 700 "$tmp" || { echo '!! unable to create a tmpdir' >&2; tmp=; exit 1; }

# main
while [ $# -gt 0 ]; do

    # movie duration/2
    dur=$(ffprobe -v panic -show_entries format=duration -of default=noprint_wrappers=1:nokey=1 "$1")
    halfdur=$(bc -l <<< "$dur / 2.00")

    # blurp frame
    termheight="$(tput lines)"
    height="$(( termheight / 3 * 2 ))"
    #echo $termheight $height

    ffmpeg -hide_banner -loglevel panic -ss "$halfdur" -i "$1" -frames:v 1 "$tmp/middle.png" -y && echo "$1" && jp2a --colors --color-depth=24 --background=dark --height=${height} --fill --border "$tmp/middle.png"
    echo; echo

    shift
done

#stty sane