#!/bin/bash

# we need youtube-dl, ffmpeg, imagemagick and gnupot installed
#dnf install youtube-dl ffmpeg imagemagick gnuplot

# 1.05M
video="https://www.youtube.com/watch?v=Y0ZKEGZpggI"
code="133"
width="21"
height="4"
x="82"
y="15"

# 1.04M
#video="https://www.youtube.com/watch?v=KYtJzRcvOzk"
#code="133"
#width="19"
#height="5"
#x="90"
#y="23"

# go get the video, and nevermind the audio
youtube-dl $video  -f $code -o vid.mp4
mkdir frames

# we crop the 1up and dump each frame.
# we take special care to not get too much glow from the score underneath it.

# when 1up is present the brightness value will be greater than a black screen.

ffmpeg -i vid.mp4 -filter:v "crop=$width:$height:$x:$y" -f image2 frames/frame-%06d.png

# for each cropped frame go get average brightness and dump it to 'results'
# we number each line, where 0 is the first frame of the video
files=`find ./frames -name "*.png" -print | sort`
n=0
for f in $files; do
  echo -n "$n, " >> results
  convert $f -colorspace gray -format "%[fx:100*mean]%%" info: >> results
  echo >> results
  n=`expr $n + 1`
done

cat << EOF > plot
set terminal svg size 600000 600 fname 'Sans' fsize 7
set output 'results.svg'
set xtics 1000
plot 'results' with lines
EOF
gnuplot plot