unitproc/bk_export_audio.sh

   1 #!/bin/bash
   2 # Desc: Extracts audio from video files
   3 # Usage: bk_export_audio.sh [input_dir] ([output_dir])
   4 # Version: 0.1.3
   5 # Depends: bash 5.1.16, GNU Coreutils (8.32)
   6
   7 # Plumbing
   8 max_jobs="$(nproc --all)"; # max parallel audio conversion jobs
   9 declare -Ag appRollCall # Associative array for storing app status
  10 declare -Ag fileRollCall # Associative array for storing file status
  11 declare -Ag dirRollCall # Associative array for storing dir status
  12
  13 yell() { echo "$0: $*" >&2; } # print script path and all args to stderr
  14 die() { yell "$*"; exit 111; } # same as yell() but non-zero exit status
  15 try() { "$@" || die "cannot $*"; } # runs args as command, reports args if command fails
  16 checkapp() {
  17     # Desc: If arg is a command, save result in assoc array 'appRollCall'
  18     # Usage: checkapp arg1 arg2 arg3 ...
  19     # Version: 0.1.1
  20     # Input: global assoc. array 'appRollCall'
  21     # Output: adds/updates key(value) to global assoc array 'appRollCall'
  22     # Depends: bash 5.0.3
  23     local returnState
  24
  25     #===Process Args===
  26     for arg in "$@"; do
  27         if command -v "$arg" 1>/dev/null 2>&1; then # Check if arg is a valid command
  28             appRollCall[$arg]="true";
  29             if ! [ "$returnState" = "false" ]; then returnState="true"; fi;
  30         else
  31             appRollCall[$arg]="false"; returnState="false";
  32         fi;
  33     done;
  34
  35     #===Determine function return code===
  36     if [ "$returnState" = "true" ]; then
  37         return 0;
  38     else
  39         return 1;
  40     fi;
  41 } # Check that app exists
  42 checkfile() {
  43     # Desc: If arg is a file path, save result in assoc array 'fileRollCall'
  44     # Usage: checkfile arg1 arg2 arg3 ...
  45     # Version: 0.1.1
  46     # Input: global assoc. array 'fileRollCall'
  47     # Output: adds/updates key(value) to global assoc array 'fileRollCall';
  48     # Output: returns 0 if app found, 1 otherwise
  49     # Depends: bash 5.0.3
  50     local returnState
  51
  52     #===Process Args===
  53     for arg in "$@"; do
  54         if [ -f "$arg" ]; then
  55             fileRollCall["$arg"]="true";
  56             if ! [ "$returnState" = "false" ]; then returnState="true"; fi;
  57         else
  58             fileRollCall["$arg"]="false"; returnState="false";
  59         fi;
  60     done;
  61
  62     #===Determine function return code===
  63     if [ "$returnState" = "true" ]; then
  64         return 0;
  65     else
  66         return 1;
  67     fi;
  68 } # Check that file exists
  69 checkdir() {
  70     # Desc: If arg is a dir path, save result in assoc array 'dirRollCall'
  71     # Usage: checkdir arg1 arg2 arg3 ...
  72     # Version 0.1.2
  73     # Input: global assoc. array 'dirRollCall'
  74     # Output: adds/updates key(value) to global assoc array 'dirRollCall';
  75     # Output: returns 0 if all args are dirs; 1 otherwise
  76     # Depends: Bash 5.0.3
  77     local returnState
  78
  79     #===Process Args===
  80     for arg in "$@"; do
  81         if [ -z "$arg" ]; then
  82             dirRollCall["(Unspecified Dirname(s))"]="false"; returnState="false";
  83         elif [ -d "$arg" ]; then
  84             dirRollCall["$arg"]="true";
  85             if ! [ "$returnState" = "false" ]; then returnState="true"; fi
  86         else
  87             dirRollCall["$arg"]="false"; returnState="false";
  88         fi
  89     done
  90
  91     #===Determine function return code===
  92     if [ "$returnState" = "true" ]; then
  93         return 0;
  94     else
  95         return 1;
  96     fi
  97 } # Check that dir exists
  98 displayMissing() {
  99     # Desc: Displays missing apps, files, and dirs
 100     # Usage: displayMissing
 101     # Version 0.1.1
 102     # Input: associative arrays: appRollCall, fileRollCall, dirRollCall
 103     # Output: stderr: messages indicating missing apps, file, or dirs
 104     # Depends: bash 5, checkAppFileDir()
 105     local missingApps value appMissing missingFiles fileMissing
 106     local missingDirs dirMissing
 107
 108     #==BEGIN Display errors==
 109     #===BEGIN Display Missing Apps===
 110     missingApps="Missing apps  :";
 111     #for key in "${!appRollCall[@]}"; do echo "DEBUG:$key => ${appRollCall[$key]}"; done
 112     for key in "${!appRollCall[@]}"; do
 113         value="${appRollCall[$key]}";
 114         if [ "$value" = "false" ]; then
 115             #echo "DEBUG:Missing apps: $key => $value";
 116             missingApps="$missingApps""$key ";
 117             appMissing="true";
 118         fi;
 119     done;
 120     if [ "$appMissing" = "true" ]; then  # Only indicate if an app is missing.
 121         echo "$missingApps" 1>&2;
 122     fi;
 123     unset value;
 124     #===END Display Missing Apps===
 125
 126     #===BEGIN Display Missing Files===
 127     missingFiles="Missing files:";
 128     #for key in "${!fileRollCall[@]}"; do echo "DEBUG:$key => ${fileRollCall[$key]}"; done
 129     for key in "${!fileRollCall[@]}"; do
 130         value="${fileRollCall[$key]}";
 131         if [ "$value" = "false" ]; then
 132             #echo "DEBUG:Missing files: $key => $value";
 133             missingFiles="$missingFiles""$key ";
 134             fileMissing="true";
 135         fi;
 136     done;
 137     if [ "$fileMissing" = "true" ]; then  # Only indicate if an app is missing.
 138         echo "$missingFiles" 1>&2;
 139     fi;
 140     unset value;
 141     #===END Display Missing Files===
 142
 143     #===BEGIN Display Missing Directories===
 144     missingDirs="Missing dirs:";
 145     #for key in "${!dirRollCall[@]}"; do echo "DEBUG:$key => ${dirRollCall[$key]}"; done
 146     for key in "${!dirRollCall[@]}"; do
 147         value="${dirRollCall[$key]}";
 148         if [ "$value" = "false" ]; then
 149             #echo "DEBUG:Missing dirs: $key => $value";
 150             missingDirs="$missingDirs""$key ";
 151             dirMissing="true";
 152         fi;
 153     done;
 154     if [ "$dirMissing" = "true" ]; then  # Only indicate if an dir is missing.
 155         echo "$missingDirs" 1>&2;
 156     fi;
 157     unset value;
 158     #===END Display Missing Directories===
 159
 160     #==END Display errors==
 161 } # Display missing apps, files, dirs
 162 showUsage() {
 163     # Desc: Display script usage information
 164     # Usage: showUsage
 165     # Version 0.0.1
 166     # Input: none
 167     # Output: stdout
 168     # Depends: GNU-coreutils 8.30 (cat)
 169     cat <<'EOF'
 170     USAGE:
 171         bk_export_audio.sh [DIR in] ([DIR out])
 172
 173     EXAMPLE:
 174       bk_export_audio.sh ./videos/ ./exported_audio/
 175       bk_export_audio.sh ./videos/
 176 EOF
 177 } # Display information on how to use this script.
 178 get_audio_format() {
 179     # Desc: Gets audio format of file as string
 180     # Usage: get_audio_format arg1
 181     # Depends: ffprobe
 182     # Version: 0.0.1
 183     # Input: arg1: input file path
 184     # Output: stdout (if valid audio format)
 185     #         exit code 0 if audio file; 1 otherwise
 186     # Example: get_audio_format myvideo.mp4
 187     #   Note: Would return "opus" if full ffprobe report had 'Audio: opus, 48000 Hz, stereo, fltp'
 188     # Note: Not tested with videos containing multiple video streams
 189     # Ref/Attrib: [1] https://stackoverflow.com/questions/5618363/is-there-a-way-to-use-ffmpeg-to-determine-the-encoding-of-a-file-before-transcod
 190     #             [2] https://stackoverflow.com/questions/44123532/how-to-find-out-the-file-extension-for-extracting-audio-tracks-with-ffmpeg-and-p#comment88464070_50723126
 191     local audio_format file_in;
 192     local return_state;
 193     file_in="$1";
 194
 195     # Return error exit code if not audio file
 196     ## Return error if ffprobe itself exited on error
 197     if ! ffprobe -v error -select_streams a -show_entries stream=codec_name -of default=nokey=1:noprint_wrappers=1 "$file_in" 1>/dev/null 2>&1; then
 198         return_state="false";
 199     fi;
 200
 201     # Get audio format
 202     audio_format="$(ffprobe -v error -select_streams a -show_entries stream=codec_name -of default=nokey=1:noprint_wrappers=1 "$file_in")"; # see [1]
 203
 204     ## Return error if audio format is incorrectly formatted (e.g. reject if contains spaces)
 205     pattern="^[[:alnum:]]+$"; # alphanumeric string with no spaces
 206     if [[ $audio_format =~ $pattern ]]; then
 207         return_state="true";
 208         # Report audio format
 209         echo "$audio_format";
 210     else
 211         return_state="false";
 212     fi;
 213
 214     # Report exit code
 215     if [[ $return_state = "true" ]]; then
 216         return 0;
 217     else
 218         return 1;
 219     fi;
 220 } # Get audio format as stdout
 221 extract_audio_file() {
 222     # Desc: Use ffmpeg to creates audio file from input video file
 223     # Usage: extract_audio_file arg1 arg2 arg3
 224     # Depends: ffmpeg
 225     # Input: arg1: input video file path
 226     #        arg2: desired output file extension
 227     #        arg3: output dir path
 228     # Output: audio file at path [arg3]/[arg1].[arg2]
 229     local file_in file_in_ext dir_out file_in_basename path_out;
 230     file_in="$1";
 231     file_in_ext="$2";
 232     dir_out="$3";
 233     file_in_basename="$(basename "$file_in")";
 234     path_out="$dir_out"/"$file_in_basename"."$file_in_ext";
 235
 236     # Skip if output file already exists.
 237     if [[ -f "$path_out" ]]; then return 1; fi;
 238
 239     # Extract audio file
 240     ffmpeg -i "$file_in" -vn -acodec copy "$path_out";
 241 } # Create audio file from video file
 242 count_jobs() {
 243     # Desc: Count and return total number of jobs
 244     # Usage: count_jobs
 245     # Input: None.
 246     # Output: stdout   integer number of jobs
 247     # Depends: Bash 5.1.16
 248     # Example: while [[$(count_jobs) -gt 0]]; do echo "Working..."; sleep 1; done;
 249     # Version: 0.0.1
 250
 251     local job_count;
 252     job_count="$(jobs -r | wc -l | tr -d ' ' )";
 253     #yell "DEBUG:job_count:$job_count";
 254     if [[ -z $job_count ]]; then job_count="0"; fi;
 255     echo "$job_count";
 256 }; # Return number of background jobs
 257 job() {
 258     # Input: arg1: file :   file to check and, if audio, export
 259     #        arg2: dir_out: output dir
 260     local file dir_out;
 261     file="$1";
 262     dir_out="$2";
 263     aud_format="$(get_audio_format "$file")"; # Get audio format as file extension string
 264     file_basename="$(basename "$file")"; # Get basename for debugging
 265     yell "DEBUG:file_basename:$file_basename";
 266     yell "DEBUG:aud_format:$aud_format";
 267     yell "DEBUG:";
 268
 269     # Ignore files that return blank $aud_format
 270     if [[ -z $aud_format ]]; then
 271         yell "DEBUG:Not an audio file:$file";
 272         return 1;
 273     fi;
 274
 275     # Convert video to audio
 276     extract_audio_file "$file" "$aud_format" "$dir_out";
 277 }; # One file check and extraction job
 278 main() {
 279     # Depends: yell(), die(), try()
 280     #     checkapp(), checkfile(), checkdir(), displayMissing(), showUsage(),
 281     #     extract_audio_file() get_audio_format()
 282     #   BK-2020-03: count_jobs v0.0.1
 283     script_pwd="$(pwd)";
 284     dir_in="$1";
 285     dir_out="$2";
 286
 287     # Check argument count
 288     if [[ $# -lt 1 ]]; then
 289         showUsage;
 290         die "ERROR:Not enough arguments:$#";
 291     fi;
 292
 293     # Check apps, dirs
 294     checkapp ffmpeg ffprobe date nproc;
 295     displayMissing;
 296
 297     if ! checkdir "$dir_in"; then
 298         showUsage;
 299         displayMissing;
 300         die "ERROR:Missing input directory."
 301     fi;
 302     if ! checkdir "$dir_out"; then
 303         yell "NOTICE:Output directory not specified. Creating output directory in current working directory:$script_pwd";
 304         timestamp="$(date +%Y%m%dT%H%M%S%z)"; # iso-8601 without separators
 305         dir_out="$script_pwd"/"$timestamp"..output;
 306         try mkdir "$dir_out";
 307     fi;
 308
 309     # Do work
 310     yell "DEBUG:dir_in:$dir_in":
 311     yell "DEBUG:dir_out:$dir_out";
 312     while read -r file; do
 313         yell "DEBUG:count_jobs:$(count_jobs)";
 314         while [[ "$(count_jobs)" -ge $max_jobs ]]; do sleep 0.01s; done; # limit jobs
 315         job "$file" "$dir_out" &
 316     done < <(find "$dir_in" -type f);
 317
 318     # Announce completion
 319     while [[ "$(count_jobs)" -gt 0 ]]; do sleep 1; done;
 320     printf "\n" 1>&2; yell "STATUS:Done.";
 321 }; # main program
 322
 323 #export -f get_audio_format count_jobs extract_audio_file;
 324 main "$@";
 325
 326 # Author: Steven Baltaktei Sandoval
 327 # License: GPLv3+