WIP: Automatic scene detection of Editorial Reference movies

scene_detection.sh

#!/bin/bash

input_video=$1

# Parameters
scene_detection_score="0.3"
tesseract="/Users/vvzen/Desktop/framestore/experimental-development/automatic-TO-recognition/ocr/tesseract/tesseract"
# My testing has been done with
# tesseract 5.0.1-9-g31a968
#  leptonica-1.81.1
#   libgif 5.2.1 : libjpeg 9d : libpng 1.6.37 : libtiff 4.3.0 : zlib 1.2.11 : libwebp 1.2.1 : libopenjp2 2.4.0
#  Found AVX2
#  Found AVX
#  Found FMA
#  Found SSE4.1
#  Found libcurl/7.54.0 LibreSSL/2.6.5 zlib/1.2.11 nghttp2/1.24.1

output_dir_name="output-frames-4"

if [ -f "$input_video" ]; then
    echo "Reading $input_video"
else
    echo "$input_video was not found on disk."
    echo "Please specify a valid file!"
    exit 1
fi

mkdir -p ./$output_dir_name
ffmpeg -i $input_video -filter:v "select=gt(scene\,$scene_detection_score)" -vsync vfr $output_dir_name/frame%d.jpg

pushd $output_dir_name

num_files=$(find . -type f -name "frame*.jpg" | wc -l)
current_file_index=0

for file in $(find . -type f -name "*.jpg"); do
    echo "Processing frame $current_file_index / $num_files"
    filename=$(basename $file)

    # Pre-processing steps via imagemagick
    # 1. Add border around image to help OCR
    # 2. Convert to black and white to facilitate thresholding
    convert ./$filename -colorspace Gray -bordercolor Black -border 10x10 "./$filename"

    # OCR via tesseract
    "$tesseract" ./$filename ./$filename.content \
        --psm 11 \
        -c tessedit_write_images=1 \
        -c load_system_dawg=0 \
        -c load_freq_dawg=0 \
        -c thresholding_score_fraction=0.2

    current_file_index=$((current_file_index+1))
done

popd