Read FLAC TITLE metadata tag

- Scan FLAC data for TITLE metadata tag and use for WAV file name, if present

Author: ScriptTiger

README.md

@@ -12,7 +12,7 @@ Argument                  | Description
 
 `-` can be used in place of `<file>` to designate standard output as the destination. When piping a FLAC stream, the complete header is included. However, when piping a WAV stream, the header is unfinished until the write operation is complete, meaning you may have to skip the first 44 bytes in order for the receiving application to process the stream in real time.
 
-Without any arguments, the embedded FLAC data will be transcoded into the working directory to a WAV file of the same name as the executable, except with the `.wav` extension. So, command-line usage is only optional and the end user can just execute the application as they would any other application for this default behavior.
+Without any arguments, the embedded FLAC data will be transcoded into the working directory to a WAV file of the same name as the executable, or TITLE metadata tag if present within the FLAC, except with the `.wav` extension. So, command-line usage is only optional and the end user can just execute the application as they would any other application for this default behavior.
 
 # Appending a FLAC file to a stand-alone FLACSFX executable, recommended for most users
 Download the latest pre-built release for the intended target system:  

flacsfx.go

@@ -103,6 +103,7 @@ func main() {
 		// Display stream info and exit
 		if info {
 			os.Stdout.WriteString(
+				"TITLE="+wavName+"\n"+
 				"codec_name=flac\n"+
 				"codec_long_name=FLAC (Free Lossless Audio Codec)\n"+
 				"codec_type=audio\n"+

sa.go

@@ -17,22 +17,59 @@ func init() {
 	filePath, _ := os.Executable()
 	filePath, _ = filepath.EvalSymlinks(filePath)
 
-	// Name wav file after executable
-	wavName = strings.TrimSuffix(filepath.Base(filePath), filepath.Ext(filePath))+".wav"
-
 	// Slurp file into memory
 	fileData, _ := os.ReadFile(filePath)
 
 	// Determine length of transcoder / start of FLAC data
+	// Find TITLE tag and use for file name if present
 	tcSize := int64(1000000)
+	var titleTagBuilder strings.Builder
 	for {
 		if fileData[tcSize-1] == 0x00 &&
-			fileData[tcSize] == 0x66 &&
-			fileData[tcSize+1] == 0x4c &&
-			fileData[tcSize+2] == 0x61 &&
-			fileData[tcSize+3] == 0x43 &&
-			fileData[tcSize+4] == 0x00 {
-				break
+		fileData[tcSize] == 0x66 &&
+		fileData[tcSize+1] == 0x4c &&
+		fileData[tcSize+2] == 0x61 &&
+		fileData[tcSize+3] == 0x43 &&
+		fileData[tcSize+4] == 0x00 {
+			titleTag := tcSize+32
+			for {
+				if fileData[titleTag] == 0x00 &&
+				fileData[titleTag+1] == 0x54 &&
+				fileData[titleTag+2] == 0x49 &&
+				fileData[titleTag+3] == 0x54 &&
+				fileData[titleTag+4] == 0x4C &&
+				fileData[titleTag+5] == 0x45 &&
+				fileData[titleTag+6] == 0x3D {
+					titleTag = titleTag+7
+					for {
+						if fileData[titleTag+1] == 0x00 {break}
+						titleTagBuilder.WriteByte(fileData[titleTag])
+						titleTag++
+					}
+					break
+				}
+				if (int(titleTag) == len(fileData)-6) ||
+				(fileData[titleTag] == 0x00 &&
+				fileData[titleTag+1] == 0x00 &&
+				fileData[titleTag+2] == 0x00 &&
+				fileData[titleTag+3] == 0x00 &&
+				fileData[titleTag+4] == 0x00 &&
+				fileData[titleTag+5] == 0x00 &&
+				fileData[titleTag+6] == 0x00 &&
+				fileData[titleTag+7] == 0x00 &&
+				fileData[titleTag+8] == 0x00 &&
+				fileData[titleTag+9] == 0x00 &&
+				fileData[titleTag+10] == 0x00 &&
+				fileData[titleTag+11] == 0x00 &&
+				fileData[titleTag+12] == 0x00 &&
+				fileData[titleTag+13] == 0x00 &&
+				fileData[titleTag+14] == 0x00 &&
+				fileData[titleTag+15] == 0x00) {
+					break
+				}
+				titleTag++
+			}
+		break
 		}
 		if int(tcSize) == len(fileData)-6 {
 			os.Stdout.WriteString("No FLAC data found.")
@@ -41,6 +78,13 @@ func init() {
 		tcSize++
 	}
 
+	// Name wav file after executable, or title tag if present
+	if titleTagBuilder.Len() == 0 {
+		wavName = strings.TrimSuffix(filepath.Base(filePath), filepath.Ext(filePath))+".wav"
+	} else {
+		wavName = titleTagBuilder.String()+".wav"
+	}
+
 	// Calculate length of FLAC data
 	flacSize := int64(len(fileData))-tcSize