| 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+ |