screenshot and mediainfo video files

mediashot.sh

#!/usr/local/bin/bash
#
# Written by ump721
# Based on and inspired by dsl420's original script
# 
# Usage:
#      mediashot video.mkv [destination_folder] [cap_name] [number_of_caps]
#
# Defaults:
#      destination_folder   same folder as input file
#      cap_name             input file name (plus appropriate extensions)
#      number_of_caps       10    
#
# Example:
#      mediashot my_video.mkv ~/capsToUpload my_video_cap 5
#
# Would create the following files:
#      ~/capsToUpload/my_video_cap.1.png
#      ~/capsToUpload/my_video_cap.2.png
#      ~/capsToUpload/my_video_cap.3.png
#      ~/capsToUpload/my_video_cap.4.png 
#      ~/capsToUpload/my_video_cap.5.png
#      ~/capsToUpload/my_video_cap.mediainfo
 
check_dependencies() {
  check_dependency ffmpeg
  check_dependency ffprobe
  check_dependency mediainfo
}
 
check_dependency() {
  local name=$1
 
  hash "$name" > /dev/null 2>&1
  if [ $? -eq 1 ]; then
    echo "Missing dependency: ${name}"
    exit 0
  fi
}
 
echo_red() {
  local red="\033[0;31m"
  local reset="\033[0m" # Clear set colors
  local output=$*
 
  echo -e "${red}${output}${reset}"
}
 
calc() {
  local precision=3
 
  bc <<< "scale=${precision}; $*"
}
 
calc_frame_position() {
  local duration=$1
  local total_frames=$2
  local current_frame=$3
 
  local offset
  local increment
 
  increment=$(calc "$duration / $total_frames")
  offset=$(calc "$increment / 2")
 
  calc "($increment * $current_frame) - $offset"
}
 
get_duration() {
  local file=$1
 
  ffprobe -i "$file" -show_format -v quiet | sed -n 's/duration=//p'
}
 
write_screencap() {
  local file=$1
  local position=$2
  local output_file=$3
 
  ffmpeg -ss "$position" -i "$file" -y -vframes 1 -vf "scale='max(sar,1)*iw':'max(1/sar,1)*ih'" -v quiet "${output_file}.png"
}
 
write_mediainfo() {
  local file=$1
  local output=$2
 
  mediainfo "$file" > "${output}.mediainfo"
}
 
main() {
  local input_file=$1
  local output_dir=$2
  local output_file_name=$3
  local number_of_caps=$4
 
  local output
  local duration
 
mkdir "$output_dir" &> /dev/null 
  # Set defaults
  output_dir=${output_dir:=$(dirname "$input_file")}
  output_file_name=${output_file_name:=$input_file}
  number_of_caps=${number_of_caps:=10}
    
  if [ ! -f "$input_file" ]; then
    echo_red "Input file not found: $input_file"
    echo_red "Usage: mediashot INPUT [create_destination_folder] [cap_name] [number_of_caps]"
    exit 1
  fi
 
#  if [ ! -d "$output_dir" ]; then
#   echo_red "Output directory not found: $output_dir"
#   exit 1
#  fi
 
  output="${output_dir}/${output_file_name}"
  duration=$(get_duration "$input_file")
 
  printf "Writing mediainfo... "
  write_mediainfo "$input_file" "$output"
  printf "done\n"
 
  # create screen caps
  for current_cap_index in $(seq -w 1 1 "$number_of_caps"); do
    printf "Processing %s/%s... " "$current_cap_index" "$number_of_caps"
    write_screencap "$input_file" \
      "$(calc_frame_position "$duration" "$number_of_caps" "$current_cap_index")" \
      "${output}.${current_cap_index}"
    printf "done\n"
  done
}
 
check_dependencies
main "$@"