metadata scripts

quiethost/metadata_search_replace.sh

@@ -0,0 +1,47 @@
+#!/usr/bin/env bash
+
+find . \( -iname '*.mp3' -o -iname '*.m4a' -o -iname '*.m4b' \) -print0 |
+while IFS= read -r -d '' f; do
+
+    comment=$(ffprobe -v error \
+        -show_entries format_tags=comment \
+        -of default=nw=1:nk=1 \
+        -- "$f")
+
+    [[ $comment =~ ^[Rr]ead[[:space:]]+[Bb]y[[:space:]]+(.+) ]] || continue
+
+    composer="${BASH_REMATCH[1]}"
+    echo "Updating: $f"
+    echo "  Composer: $composer"
+
+    dir=$(dirname -- "$f")
+    base=$(basename -- "$f")
+    ext="${base##*.}"
+
+    case "${ext,,}" in
+        mp3) format=mp3 ;;
+        m4a|m4b) format=ipod ;;
+        *) continue ;;
+    esac
+
+    tmp=$(mktemp -p "$dir" ".${base}.XXXXXX") || {
+        echo "Couldn't create temporary file in $dir" >&2
+        continue
+    }
+
+    if ffmpeg -nostdin -v error -y \
+        -i "$f" \
+        -map 0 \
+        -map_metadata 0 \
+        -c copy \
+        -metadata composer="$composer" \
+        -metadata comment= \
+        -f "$format" \
+        "$tmp"
+    then
+        mv -f -- "$tmp" "$f"
+    else
+        echo "FAILED: $f" >&2
+        rm -f -- "$tmp"
+    fi
+done