Merge pull request #44 from cgzirim/development

Fix Critical Audio Fingerprinting Algorithm Bugs

.dockerignore

@@ -1,28 +1,88 @@
-# Binaries for programs and plugins
+# Git
-*.exe
+.git
-*.ogg
+.gitignore
-*.m4a
+.gitattributes
-*.zip
-*.exe~
-*.dll
-*.so
-*.dylib
 
-# Test binary, built with `go test -c`
+# Documentation
-*.test
+*.md
+!README.md
+LICENSE
 
-# Output of the go coverage tool, specifically when used with LiteIDE
+# IDE
-*.out
-
-# Dependency directories (remove the comment below to include it)
-# vendor/
-
-# Go workspace file
-go.work
-**/songs
 .vscode
+.idea
+*.swp
+*.swo
+*~
 
-package-lock.json
+# OS
+.DS_Store
+Thumbs.db
 
-*sqlite3
+# Node
+client/node_modules
+client/.env.local
+client/.env.development.local
+client/.env.test.local
+client/.env.production.local
+client/build
+client/coverage
+client/npm-debug.log*
+client/yarn-debug.log*
+client/yarn-error.log*
+
+# Go
+server/seek-tune
+server/*.exe
+server/*.test
+server/*.out
+server/vendor/
+
+# Application data (don't copy into image)
+server/songs/**
+server/recordings/**
+server/snippets/**
+server/tmp/**
+server/db/*.sqlite3
+server/db/*.db
+
+# Audio files
+*.mp3
+*.wav
+*.m4a
+*.ogg
+*.flac
+*.aac
+
+# Archives
+*.zip
+*.tar
+*.gz
+*.rar
+
+# Environment
 .env
+.env.*
+!.env.example
+
+# CI/CD
+.github
+.gitlab-ci.yml
+.travis.yml
+
+# Docker
+docker-compose*.yml
+!docker-compose.yml
+Dockerfile*
+!Dockerfile
+
+# WASM (already built separately if needed)
+wasm/fingerprint.wasm
+wasm/go.sum
+
+# Scripts
+scripts/
+appspec.yml
+
+# Logs
+*.log

.env.example

@@ -1,9 +0,0 @@
-DB_TYPE=mongo
-DB_USER=user
-DB_PASS=password
-DB_NAME=seek-tune
-DB_HOST=192.168.0.1
-DB_PORT=27017
-REACT_APP_BACKEND_URL=http://localhost:5000
-SPOTIFY_CLIENT_ID=yourclientid
-SPOTIFY_CLIENT_SECRET=yoursecret

.gitignore

@@ -29,3 +29,5 @@ go.work
 package-lock.json
 *sqlite3
 .env
+
+token.json

Dockerfile

@@ -1,33 +1,63 @@
-# build react
+# Build React frontend
 FROM node:20-alpine AS build_react_stage
 
-RUN mkdir -p /home/react
+WORKDIR /app/client
-WORKDIR /home/react
 
-COPY client/package.json ./
+COPY client/package*.json ./
-RUN npm install
+RUN npm ci --only=production && npm cache clean --force
 
 COPY client/ ./
 ARG REACT_APP_BACKEND_URL
 ENV REACT_APP_BACKEND_URL=${REACT_APP_BACKEND_URL}
 RUN npm run build
 
-# build go
+# Build Go backend
-FROM golang:1.21.6
+FROM golang:1.24-alpine AS build_go_stage
 
-WORKDIR /home/seek-tune
+RUN apk add --no-cache git ca-certificates tzdata gcc musl-dev
+
+WORKDIR /app/server
 
 COPY server/go.mod server/go.sum ./
-RUN go mod download
+RUN go mod download && go mod verify
 
 COPY server/ ./
-ENV ENV=production
+RUN go build -ldflags="-w -s" -o seek-tune
+
+# Final runtime image
+FROM alpine:latest
+
+# Install runtime dependencies
+RUN apk add --no-cache \
+    ca-certificates \
+    tzdata \
+    ffmpeg \
+    python3 \
+    py3-pip \
+    && pip3 install --no-cache-dir yt-dlp --break-system-packages
+
+WORKDIR /app
+
+COPY --from=build_go_stage /app/server/seek-tune .
 
 RUN mkdir -p static
-COPY --from=build_react_stage /home/react/build static
+COPY --from=build_react_stage /app/client/build ./static
 
-RUN go build -o seek-tune
+RUN mkdir -p db songs recordings snippets tmp && \
+    chmod -R 755 db songs recordings snippets tmp
+
+ENV ENV=production
 
 EXPOSE 5000
 
-CMD [ "/home/seek-tune/seek-tune", "serve" ]
+HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
+    CMD wget --no-verbose --tries=1 --spider http://localhost:5000/ || exit 1
+
+# Run as non-root user for security
+RUN addgroup -g 1001 -S appuser && \
+    adduser -u 1001 -S appuser -G appuser && \
+    chown -R appuser:appuser /app
+
+USER appuser
+
+CMD ["./seek-tune", "serve", "http", "5000"]

README.md

@@ -8,21 +8,17 @@
 </a>
 </p>
 
-<p align="center"><a href="https://drive.google.com/file/d/1I2esH2U4DtXHsNgYbUi4OL-ukV5i_1PI/view" target="_blank">Demo in Video</a></p>
+<p align="center"><a href="https://drive.google.com/file/d/1I2esH2U4DtXHsNgYbUi4OL-ukV5i_1PI/view" target="_blank">Demo in Video</a> | <a href="https://www.youtube.com/watch?v=a0CVCcb0RJM" target="_blank">How it was made (YouTube)</a></p>
 
 ## Description 🎼
 SeekTune is an implementation of Shazam's song recognition algorithm based on insights from these [resources](#resources--card_file_box). It integrates Spotify and YouTube APIs to find and download songs.
 
-[//]: # (## Current Limitations
-While the algorithm works excellently in matching a song with its exact file, it doesn't always find the right match from a recording. However, this project is still a work in progress. I'm hopeful about making it work, but I could definitely use some help :slightly_smiling_face:.   
-Additionally, it currently only supports song files in WAV format.
-)
-
 ## Installation :desktop_computer:
 ### Prerequisites
 - Golang: [Install Golang](https://golang.org/dl/)
 - FFmpeg: [Install FFmpeg](https://ffmpeg.org/download.html)
-- NPM: To run the client (frontend).
+- NPM: [Install Node](https://nodejs.org/en/download)
+- YT-DLP: [Install YT-DLP](https://github.com/yt-dlp/yt-dlp/wiki/Installation)
 
 ### Steps
 📦 Clone the repository:
@@ -42,27 +38,17 @@ Prerequisites: [Docker](https://docs.docker.com/get-docker/) and [Docker Compose
    docker-compose down
    ```
 
-#### 🎧 Spotify API
+#### 🎧 Spotify API Setup
 
-To access Spotify metadata, the project now uses the official [Spotify Web API](https://developer.spotify.com/documentation/web-api/). This requires creating a developer application and retrieving a client ID and client secret.
+1. Get credentials: Follow the [official getting started guide](https://developer.spotify.com/documentation/web-api/tutorials/getting-started) to create a Spotify app and obtain your **Client ID** and **Client Secret**.
 
-Follow the [official getting started guide](https://developer.spotify.com/documentation/web-api/tutorials/getting-started#request-an-access-token) to:
+2. Configure: Create a `.env` file in the `server` directory:
+   ```bash
+   SPOTIFY_CLIENT_ID=your-client-id
+   SPOTIFY_CLIENT_SECRET=your-client-secret
+   ```
 
-1. Create a Spotify developer app.
+The app will automatically fetch and cache access tokens as needed.
-2. Copy your **Client ID** and **Client Secret**.
-
-##### Setting up Credentials
-Instead of using a credentials.json file, the application now reads these values from environment variables.
-
-Create a .env file in the server directory  with the following content:
-
-```
-SPOTIFY_CLIENT_ID=your-client-id
-SPOTIFY_CLIENT_SECRET=your-client-secret
-```
-
-Make sure this .env file is loaded into your environment before running the server.
-The application will automatically read this file to fetch and cache access tokens. If the token is expired or missing, a new one will be requested.
 
 #### 💻 Set Up Natively
 Install dependencies for the backend
@@ -109,7 +95,12 @@ go run *.go find <path-to-wav-file>
 ```
 #### ▸ Delete fingerprints and songs 🗑️ 
 ```
+# Delete only database (default)
 go run *.go erase
+go run *.go erase db
+
+# Delete both database and song files
+go run *.go erase all
 ```
 
 ## Example :film_projector:  

client/.env.example

@@ -0,0 +1 @@
+REACT_APP_BACKEND_URL=http://localhost:5000 

client/src/App.js

@@ -15,7 +15,8 @@ import { fetchFile } from '@ffmpeg/util';
 
 import AnimatedNumber from "./components/AnimatedNumber";
 
-const server = process.env.REACT_APP_BACKEND_URL || "http://localhost:5000";
+const server = process.env.REACT_APP_BACKEND_URL || "http://localhost:5500";
+const recordStereo = process.env.REACT_APP_RECORD_STEREO === "true" || false;
 // https://seek-tune-rq4gn.ondigitalocean.app/
 
 var socket = io(server);
@@ -91,7 +92,7 @@ function App() {
       try {
         const go = new window.Go();
         const result = await WebAssembly.instantiateStreaming(
-          fetch("/main.wasm"), 
+          fetch("/fingerprint.wasm"), 
           go.importObject
         );
         go.run(result.instance);
@@ -175,15 +176,15 @@ function App() {
         cleanUp();
 
         const inputFile = 'input.wav';
-        const outputFile = 'output_mono.wav';
+        const outputFile = 'output_formatted.wav';
 
-        // Convert audio to mono with a sample rate of 44100 Hz
         await ffmpeg.writeFile(inputFile, await fetchFile(blob))
         const exitCode = await ffmpeg.exec([
           '-i', inputFile,
           '-c', 'pcm_s16le',
           '-ar', '44100',
-          '-ac', '1',
+          '-ac', recordStereo ? '2' : '1',
+          '-acodec', 'pcm_s16le',
           '-f', 'wav',
           outputFile
         ]);
@@ -191,11 +192,11 @@ function App() {
           throw new Error(`FFmpeg exec failed with exit code: ${exitCode}`);
         }
 
-        const monoData = await ffmpeg.readFile(outputFile);
+        const audioData = await ffmpeg.readFile(outputFile);
-        const monoBlob = new Blob([monoData.buffer], { type: 'audio/wav' });
+        const audioBlob = new Blob([audioData.buffer], { type: 'audio/wav' });
 
         const reader = new FileReader();
-        reader.readAsArrayBuffer(monoBlob);
+        reader.readAsArrayBuffer(audioBlob);
         reader.onload = async (event) => {
           const arrayBuffer = event.target.result;
           const audioContext = new AudioContext();
@@ -205,7 +206,11 @@ function App() {
           const audioData = audioBufferDecoded.getChannelData(0);
           const audioArray = Array.from(audioData);
 
-          const result = genFingerprint(audioArray, audioBufferDecoded.sampleRate);
+          const result = genFingerprint(
+            audioArray,
+            audioBufferDecoded.sampleRate,
+            audioBufferDecoded.numberOfChannels
+          );
           if (result.error !== 0) {
             toast["error"](() => <div>An error occured</div>)
             console.log("An error occured: ", result)
@@ -288,7 +293,7 @@ function App() {
   return (
     <div className="App">
       <div className="TopHeader">
-        <h2 style={{ color: "#374151" }}>!Shazam</h2>
+        <h2 style={{ color: "#374151" }}>SeekTune</h2>
         <h4 style={{ display: "flex", justifyContent: "flex-end" }}>
           <AnimatedNumber includeComma={true} animateToNumber={totalSongs} />
           &nbsp;Songs

docker-compose.yml

@@ -1,15 +1,21 @@
-version: '3.1'
+version: '3.8'
 
 volumes:
   seek-tune-db:
+    driver: local
   seek-tune-songs:
+    driver: local
+  seek-tune-recordings:
+    driver: local
 
 services:
   seek-tune:
-    image: 'seek-tune'
+    image: seek-tune:latest
+    container_name: seek-tune-app
     restart: unless-stopped
+    
     ports:
-      - 8080:5000
+      - "${HOST_PORT:-8080}:5000"
 
     environment:
       DB_TYPE: ${DB_TYPE:-sqlite}
@@ -19,13 +25,66 @@ services:
       DB_HOST: ${DB_HOST:-localhost}
       DB_PORT: ${DB_PORT:-27017}
       
+      ENV: production
       REACT_APP_BACKEND_URL: ${REACT_APP_BACKEND_URL:-http://localhost:8080}
       
+      SPOTIFY_CLIENT_ID: ${SPOTIFY_CLIENT_ID:-}
+      SPOTIFY_CLIENT_SECRET: ${SPOTIFY_CLIENT_SECRET:-}
+
     build:
       context: .
+      dockerfile: Dockerfile
       args:
         REACT_APP_BACKEND_URL: ${REACT_APP_BACKEND_URL:-http://localhost:8080}
+      cache_from:
+        - seek-tune:latest
 
     volumes:
-      - seek-tune-db:/home/seek-tune/db
+      - seek-tune-db:/app/db
-      - seek-tune-songs:/home/seek-tune/songs
+      - seek-tune-songs:/app/songs
+      - seek-tune-recordings:/app/recordings
+      # Optional: Mount local songs directory for development
+      # - ./server/songs:/app/songs
+    
+    # Resource limits (adjust based on your needs)
+    deploy:
+      resources:
+        limits:
+          cpus: '2.0'
+          memory: 2G
+        reservations:
+          cpus: '0.5'
+          memory: 512M
+    
+    healthcheck:
+      test: ["CMD", "wget", "--no-verbose", "--tries=1", "--spider", "http://localhost:5000/"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+      start_period: 10s
+    
+    logging:
+      driver: "json-file"
+      options:
+        max-size: "10m"
+        max-file: "3"
+
+  # Optional: MongoDB service (if using MongoDB instead of SQLite)
+  # mongodb:
+  #   image: mongo:7
+  #   container_name: seek-tune-mongo
+  #   restart: unless-stopped
+  #   environment:
+  #     MONGO_INITDB_ROOT_USERNAME: ${DB_USER:-root}
+  #     MONGO_INITDB_ROOT_PASSWORD: ${DB_PASSWORD:-password}
+  #     MONGO_INITDB_DATABASE: ${DB_NAME:-seek_tune_db}
+  #   ports:
+  #     - "27017:27017"
+  #   volumes:
+  #     - seek-tune-db:/data/db
+  #   healthcheck:
+  #     test: echo 'db.runCommand("ping").ok' | mongosh localhost:27017/test --quiet
+  #     interval: 10s
+  #     timeout: 10s
+  #     retries: 5
+  #     start_period: 40s

server/.env.example

@@ -0,0 +1,14 @@
+DB_TYPE=mongo # or sqlite
+DB_USER=user
+DB_PASS=password
+DB_NAME=seek-tune
+DB_HOST=192.168.0.1
+DB_PORT=27017
+
+# Set to true to enable stereo fingerprinting (uses more storage but may improve accuracy)
+FINGERPRINT_STEREO=false
+
+SPOTIFY_CLIENT_ID=yourclientid
+SPOTIFY_CLIENT_SECRET=yoursecret
+
+

server/cmdHandlers.go

@@ -10,6 +10,7 @@ import (
 	"net/http"
 	"os"
 	"path/filepath"
+	"runtime"
 	"song-recognition/db"
 	"song-recognition/shazam"
 	"song-recognition/spotify"
@@ -34,19 +35,24 @@ const (
 var yellow = color.New(color.FgYellow)
 
 func find(filePath string) {
-	wavInfo, err := wav.ReadWavInfo(filePath)
+	wavFilePath, err := wav.ConvertToWAV(filePath)
 	if err != nil {
-		yellow.Println("Error reading wave info:", err)
+		yellow.Println("Error converting to WAV:", err)
 		return
 	}
 
-	samples, err := wav.WavBytesToSamples(wavInfo.Data)
+	fingerprint, err := shazam.FingerprintAudio(wavFilePath, utils.GenerateUniqueID())
 	if err != nil {
-		yellow.Println("Error converting to samples:", err)
+		yellow.Println("Error generating fingerprint for sample: ", err)
 		return
 	}
 
-	matches, searchDuration, err := shazam.FindMatches(samples, wavInfo.Duration, wavInfo.SampleRate)
+	sampleFingerprint := make(map[uint32]uint32)
+	for address, couple := range fingerprint {
+		sampleFingerprint[address] = couple.AnchorTimeMs
+	}
+
+	matches, searchDuration, err := shazam.FindMatchesFGP(sampleFingerprint)
 	if err != nil {
 		yellow.Println("Error finding matches:", err)
 		return
@@ -193,7 +199,7 @@ func serveHTTP(socketServer *socketio.Server, serveHTTPS bool, port string) {
 	}
 }
 
-func erase(songsDir string) {
+func erase(songsDir string, dbOnly bool, all bool) {
 	logger := utils.GetLogger()
 	ctx := context.Background()
 
@@ -216,26 +222,31 @@ func erase(songsDir string) {
 		logger.ErrorContext(ctx, msg, slog.Any("error", err))
 	}
 
-	// delete song files
+	fmt.Println("Database cleared")
-	err = filepath.Walk(songsDir, func(path string, info os.FileInfo, err error) error {
-		if err != nil {
-			return err
-		}
 
-		if !info.IsDir() {
+	// delete song files only if -all flag is set
-			ext := filepath.Ext(path)
+	if all {
-			if ext == ".wav" || ext == ".m4a" {
+		err = filepath.Walk(songsDir, func(path string, info os.FileInfo, err error) error {
-				err := os.Remove(path)
+			if err != nil {
-				if err != nil {
+				return err
-					return err
+			}
+
+			if !info.IsDir() {
+				ext := filepath.Ext(path)
+				if ext == ".wav" || ext == ".m4a" {
+					err := os.Remove(path)
+					if err != nil {
+						return err
+					}
 				}
 			}
+			return nil
+		})
+		if err != nil {
+			msg := fmt.Sprintf("Error walking through directory %s: %v\n", songsDir, err)
+			logger.ErrorContext(ctx, msg, slog.Any("error", err))
 		}
-		return nil
+		fmt.Println("Songs folder cleared")
-	})
-	if err != nil {
-		msg := fmt.Sprintf("Error walking through directory %s: %v\n", songsDir, err)
-		logger.ErrorContext(ctx, msg, slog.Any("error", err))
 	}
 
 	fmt.Println("Erase complete")
@@ -249,6 +260,7 @@ func save(path string, force bool) {
 	}
 
 	if fileInfo.IsDir() {
+		var filePaths []string
 		err := filepath.Walk(path, func(filePath string, info os.FileInfo, err error) error {
 			if err != nil {
 				fmt.Printf("Error walking the path %v: %v\n", filePath, err)
@@ -256,16 +268,16 @@ func save(path string, force bool) {
 			}
 			// Process only files, skip directories
 			if !info.IsDir() {
-				err := saveSong(filePath, force)
+				filePaths = append(filePaths, filePath)
-				if err != nil {
-					fmt.Printf("Error saving song (%v): %v\n", filePath, err)
-				}
 			}
 			return nil
 		})
 		if err != nil {
 			fmt.Printf("Error walking the directory %v: %v\n", path, err)
+			return
 		}
+
+		processFilesConCurrently(filePaths, force)
 	} else {
 		err := saveSong(path, force)
 		if err != nil {
@@ -274,6 +286,50 @@ func save(path string, force bool) {
 	}
 }
 
+func processFilesConCurrently(filePaths []string, force bool) {
+	maxWorkers := runtime.NumCPU() / 2
+	numFiles := len(filePaths)
+
+	if numFiles == 0 {
+		return
+	}
+
+	if numFiles < maxWorkers {
+		maxWorkers = numFiles
+	}
+
+	jobs := make(chan string, numFiles)
+	results := make(chan error, numFiles)
+
+	for w := 0; w < maxWorkers; w++ {
+		go func(workerID int) {
+			for filePath := range jobs {
+				err := saveSong(filePath, force)
+				results <- err
+			}
+		}(w + 1)
+	}
+
+	for _, filePath := range filePaths {
+		jobs <- filePath
+	}
+	close(jobs)
+
+	successCount := 0
+	errorCount := 0
+	for i := 0; i < numFiles; i++ {
+		err := <-results
+		if err != nil {
+			fmt.Printf("Error: %v\n", err)
+			errorCount++
+		} else {
+			successCount++
+		}
+	}
+
+	fmt.Printf("\n ->> Processed %d files: %d successful, %d failed\n", numFiles, successCount, errorCount)
+}
+
 func saveSong(filePath string, force bool) error {
 	metadata, err := wav.GetMetadata(filePath)
 	if err != nil {

server/main.go

@@ -8,8 +8,8 @@ import (
 	"os"
 	"song-recognition/utils"
 
-	"github.com/mdobak/go-xerrors"
 	"github.com/joho/godotenv"
+	"github.com/mdobak/go-xerrors"
 )
 
 func main() {
@@ -32,6 +32,12 @@ func main() {
 
 	if len(os.Args) < 2 {
 		fmt.Println("Expected 'find', 'download', 'erase', 'save', or 'serve' subcommands")
+		fmt.Println("\nUsage examples:")
+		fmt.Println("  find <path_to_wav_file>")
+		fmt.Println("  download <spotify_url>")
+		fmt.Println("  erase [db | all]  (default: db)")
+		fmt.Println("  save [-f|--force] <path_to_file_or_dir>")
+		fmt.Println("  serve [-proto <http|https>] [-p <port>]")
 		os.Exit(1)
 	}
 	_ = godotenv.Load()
@@ -58,7 +64,28 @@ func main() {
 		serveCmd.Parse(os.Args[2:])
 		serve(*protocol, *port)
 	case "erase":
-		erase(SONGS_DIR)
+		// Default is to clear only database (db mode)
+		dbOnly := true
+		all := false
+
+		if len(os.Args) > 2 {
+			subCmd := os.Args[2]
+			switch subCmd {
+			case "db":
+				dbOnly = true
+				all = false
+			case "all":
+				dbOnly = false
+				all = true
+			default:
+				fmt.Println("Usage: main.go erase [db | all]")
+				fmt.Println("  db  : only clear the database (default)")
+				fmt.Println("  all : clear database and songs folder")
+				os.Exit(1)
+			}
+		}
+
+		erase(SONGS_DIR, dbOnly, all)
 	case "save":
 		indexCmd := flag.NewFlagSet("save", flag.ExitOnError)
 		force := indexCmd.Bool("force", false, "save song with or without YouTube ID")
@@ -72,6 +99,12 @@ func main() {
 		save(filePath, *force)
 	default:
 		fmt.Println("Expected 'find', 'download', 'erase', 'save', or 'serve' subcommands")
+		fmt.Println("\nUsage examples:")
+		fmt.Println("  find <path_to_wav_file>")
+		fmt.Println("  download <spotify_url>")
+		fmt.Println("  erase [db | all]  (default: db)")
+		fmt.Println("  save [-f|--force] <path_to_file_or_dir>")
+		fmt.Println("  serve [-proto <http|https>] [-p <port>]")
 		os.Exit(1)
 	}
 }

server/shazam/fingerprint.go

@@ -1,7 +1,10 @@
 package shazam
 
 import (
+	"fmt"
 	"song-recognition/models"
+	"song-recognition/utils"
+	"song-recognition/wav"
 )
 
 const (
@@ -23,7 +26,10 @@ func Fingerprint(peaks []Peak, songID uint32) map[uint32]models.Couple {
 			address := createAddress(anchor, target)
 			anchorTimeMs := uint32(anchor.Time * 1000)
 
-			fingerprints[address] = models.Couple{anchorTimeMs, songID}
+			fingerprints[address] = models.Couple{
+				AnchorTimeMs: anchorTimeMs,
+				SongID:       songID,
+			}
 		}
 	}
 
@@ -35,12 +41,52 @@ func Fingerprint(peaks []Peak, songID uint32) map[uint32]models.Couple {
 // the anchor and target points, and other bits represent the time difference (delta time)
 // between them. This function combines these components into a single address (a hash).
 func createAddress(anchor, target Peak) uint32 {
-	anchorFreq := int(real(anchor.Freq))
+	anchorFreqBin := uint32(anchor.Freq / 10) // Scale down to fit in 9 bits
-	targetFreq := int(real(target.Freq))
+	targetFreqBin := uint32(target.Freq / 10)
-	deltaMs := uint32((target.Time - anchor.Time) * 1000)
 
-	// Combine the frequency of the anchor, target, and delta time into a 32-bit address
+	deltaMsRaw := uint32((target.Time - anchor.Time) * 1000)
-	address := uint32(anchorFreq<<23) | uint32(targetFreq<<14) | deltaMs
+
+	// Mask to fit within bit constraints
+	anchorFreqBits := anchorFreqBin & ((1 << maxFreqBits) - 1) // 9 bits
+	targetFreqBits := targetFreqBin & ((1 << maxFreqBits) - 1) // 9 bits
+	deltaBits := deltaMsRaw & ((1 << maxDeltaBits) - 1)        // 14 bits (max ~16 seconds)
+
+	// Combine into 32-bit address
+	address := (anchorFreqBits << 23) | (targetFreqBits << 14) | deltaBits
 
 	return address
 }
+
+func FingerprintAudio(songFilePath string, songID uint32) (map[uint32]models.Couple, error) {
+	wavFilePath, err := wav.ConvertToWAV(songFilePath)
+	if err != nil {
+		return nil, fmt.Errorf("error converting input file to WAV: %v", err)
+	}
+
+	wavInfo, err := wav.ReadWavInfo(wavFilePath)
+	if err != nil {
+		return nil, fmt.Errorf("error reading WAV info: %v", err)
+	}
+
+	fingerprint := make(map[uint32]models.Couple)
+
+	spectro, err := Spectrogram(wavInfo.LeftChannelSamples, wavInfo.SampleRate)
+	if err != nil {
+		return nil, fmt.Errorf("error creating spectrogram: %v", err)
+	}
+
+	peaks := ExtractPeaks(spectro, wavInfo.Duration, wavInfo.SampleRate)
+	utils.ExtendMap(fingerprint, Fingerprint(peaks, songID))
+
+	if wavInfo.Channels == 2 {
+		spectro, err = Spectrogram(wavInfo.RightChannelSamples, wavInfo.SampleRate)
+		if err != nil {
+			return nil, fmt.Errorf("error creating spectrogram for right channel: %v", err)
+		}
+
+		peaks = ExtractPeaks(spectro, wavInfo.Duration, wavInfo.SampleRate)
+		utils.ExtendMap(fingerprint, Fingerprint(peaks, songID))
+	}
+
+	return fingerprint, nil
+}

server/shazam/shazam.go

@@ -5,7 +5,6 @@ package shazam
 
 import (
 	"fmt"
-	"math"
 	"song-recognition/db"
 	"song-recognition/utils"
 	"sort"
@@ -30,7 +29,8 @@ func FindMatches(audioSample []float64, audioDuration float64, sampleRate int) (
 		return nil, time.Since(startTime), fmt.Errorf("failed to get spectrogram of samples: %v", err)
 	}
 
-	peaks := ExtractPeaks(spectrogram, audioDuration)
+	peaks := ExtractPeaks(spectrogram, audioDuration, sampleRate)
+	// peaks := ExtractPeaksLMX(spectrogram, true)
 	sampleFingerprint := Fingerprint(peaks, utils.GenerateUniqueID())
 
 	sampleFingerprintMap := make(map[uint32]uint32)
@@ -38,7 +38,7 @@ func FindMatches(audioSample []float64, audioDuration float64, sampleRate int) (
 		sampleFingerprintMap[address] = couple.AnchorTimeMs
 	}
 
-	matches, _, err := FindMatchesFGP(sampleFingerprintMap)
+	matches, _, _ := FindMatchesFGP(sampleFingerprintMap)
 
 	return matches, time.Since(startTime), nil
 }
@@ -142,21 +142,32 @@ func filterMatches(
 }
 
 // analyzeRelativeTiming calculates a score for each song based on the
-// relative timing between the song and the sample's anchor times.
+// consistency of time offsets between the sample and database.
 func analyzeRelativeTiming(matches map[uint32][][2]uint32) map[uint32]float64 {
 	scores := make(map[uint32]float64)
+
 	for songID, times := range matches {
-		count := 0
+		offsetCounts := make(map[int32]int)
-		for i := 0; i < len(times); i++ {
+
-			for j := i + 1; j < len(times); j++ {
+		for _, timePair := range times {
-				sampleDiff := math.Abs(float64(times[i][0] - times[j][0]))
+			sampleTime := int32(timePair[0])
-				dbDiff := math.Abs(float64(times[i][1] - times[j][1]))
+			dbTime := int32(timePair[1])
-				if math.Abs(sampleDiff-dbDiff) < 100 { // Allow some tolerance
+			offset := dbTime - sampleTime
-					count++
+
-				}
+			// Bin offsets in 100ms buckets to allow for small timing variations
+			offsetBucket := offset / 100
+			offsetCounts[offsetBucket]++
+		}
+
+		maxCount := 0
+		for _, count := range offsetCounts {
+			if count > maxCount {
+				maxCount = count
 			}
 		}
-		scores[songID] = float64(count)
+
+		scores[songID] = float64(maxCount)
 	}
+
 	return scores
 }

server/shazam/spectrogram.go

@@ -8,13 +8,14 @@ import (
 )
 
 const (
-	dspRatio    = 4
+	dspRatio   = 4
-	freqBinSize = 1024
+	windowSize = 1024
-	maxFreq     = 5000.0 // 5kHz
+	maxFreq    = 5000.0         // 5kHz
-	hopSize     = freqBinSize / 32
+	hopSize    = windowSize / 2 // 50% overlap for better time-frequency resolution
+	windowType = "hanning"      // choices: "hanning" or "hamming"
 )
 
-func Spectrogram(sample []float64, sampleRate int) ([][]complex128, error) {
+func Spectrogram(sample []float64, sampleRate int) ([][]float64, error) {
 	filteredSample := LowPassFilter(maxFreq, float64(sampleRate), sample)
 
 	downsampledSample, err := Downsample(filteredSample, sampleRate, sampleRate/dspRatio)
@@ -22,31 +23,42 @@ func Spectrogram(sample []float64, sampleRate int) ([][]complex128, error) {
 		return nil, fmt.Errorf("couldn't downsample audio sample: %v", err)
 	}
 
-	numOfWindows := len(downsampledSample) / (freqBinSize - hopSize)
+	window := make([]float64, windowSize)
-	spectrogram := make([][]complex128, numOfWindows)
-
-	window := make([]float64, freqBinSize)
 	for i := range window {
-		window[i] = 0.54 - 0.46*math.Cos(2*math.Pi*float64(i)/(float64(freqBinSize)-1))
+		theta := 2 * math.Pi * float64(i) / float64(windowSize-1)
+		switch windowType {
+		case "hamming":
+			window[i] = 0.54 - 0.46*math.Cos(theta)
+		default: // Hanning window
+			window[i] = 0.5 - 0.5*math.Cos(theta)
+		}
 	}
 
+	// Initialize spectrogram slice
+	spectrogram := make([][]float64, 0)
+
 	// Perform STFT
-	for i := 0; i < numOfWindows; i++ {
+	for start := 0; start+windowSize <= len(downsampledSample); start += hopSize {
-		start := i * hopSize
+		end := start + windowSize
-		end := start + freqBinSize
-		if end > len(downsampledSample) {
-			end = len(downsampledSample)
-		}
 
-		bin := make([]float64, freqBinSize)
+		frame := make([]float64, windowSize)
-		copy(bin, downsampledSample[start:end])
+		copy(frame, downsampledSample[start:end])
 
-		// Apply Hamming window
+		// Apply window
 		for j := range window {
-			bin[j] *= window[j]
+			frame[j] *= window[j]
 		}
 
-		spectrogram[i] = FFT(bin)
+		// Perform FFT
+		fftResult := FFT(frame)
+
+		// Convert complex spectrum to magnitude spectrum
+		magnitude := make([]float64, len(fftResult)/2)
+		for j := range magnitude {
+			magnitude[j] = cmplx.Abs(fftResult[j])
+		}
+
+		spectrogram = append(spectrogram, magnitude)
 	}
 
 	return spectrogram, nil
@@ -107,43 +119,47 @@ func Downsample(input []float64, originalSampleRate, targetSampleRate int) ([]fl
 	return resampled, nil
 }
 
+// Peak represents a significant point in the spectrogram.
 type Peak struct {
-	Time float64
+	Freq float64 // Frequency in Hz
-	Freq complex128
+	Time float64 // Time in seconds
 }
 
 // ExtractPeaks analyzes a spectrogram and extracts significant peaks in the frequency domain over time.
-func ExtractPeaks(spectrogram [][]complex128, audioDuration float64) []Peak {
+func ExtractPeaks(spectrogram [][]float64, audioDuration float64, sampleRate int) []Peak {
 	if len(spectrogram) < 1 {
 		return []Peak{}
 	}
 
 	type maxies struct {
 		maxMag  float64
-		maxFreq complex128
 		freqIdx int
 	}
 
-	bands := []struct{ min, max int }{{0, 10}, {10, 20}, {20, 40}, {40, 80}, {80, 160}, {160, 512}}
+	bands := []struct{ min, max int }{
+		{0, 10}, {10, 20}, {20, 40}, {40, 80}, {80, 160}, {160, 512},
+	}
 
 	var peaks []Peak
-	binDuration := audioDuration / float64(len(spectrogram))
+	frameDuration := audioDuration / float64(len(spectrogram))
 
-	for binIdx, bin := range spectrogram {
+	// Calculate frequency resolution (Hz per bin)
+	effectiveSampleRate := float64(sampleRate) / float64(dspRatio)
+	freqResolution := effectiveSampleRate / float64(windowSize)
+
+	for frameIdx, frame := range spectrogram {
 		var maxMags []float64
-		var maxFreqs []complex128
+		var freqIndices []int
-		var freqIndices []float64
 
 		binBandMaxies := []maxies{}
 		for _, band := range bands {
 			var maxx maxies
 			var maxMag float64
-			for idx, freq := range bin[band.min:band.max] {
+			for idx, mag := range frame[band.min:band.max] {
-				magnitude := cmplx.Abs(freq)
+				if mag > maxMag {
-				if magnitude > maxMag {
+					maxMag = mag
-					maxMag = magnitude
 					freqIdx := band.min + idx
-					maxx = maxies{magnitude, freq, freqIdx}
+					maxx = maxies{mag, freqIdx}
 				}
 			}
 			binBandMaxies = append(binBandMaxies, maxx)
@@ -151,8 +167,7 @@ func ExtractPeaks(spectrogram [][]complex128, audioDuration float64) []Peak {
 
 		for _, value := range binBandMaxies {
 			maxMags = append(maxMags, value.maxMag)
-			maxFreqs = append(maxFreqs, value.maxFreq)
+			freqIndices = append(freqIndices, value.freqIdx)
-			freqIndices = append(freqIndices, float64(value.freqIdx))
 		}
 
 		// Calculate the average magnitude
@@ -160,17 +175,15 @@ func ExtractPeaks(spectrogram [][]complex128, audioDuration float64) []Peak {
 		for _, max := range maxMags {
 			maxMagsSum += max
 		}
-		avg := maxMagsSum / float64(len(maxFreqs)) // * coefficient
+		avg := maxMagsSum / float64(len(maxMags))
 
 		// Add peaks that exceed the average magnitude
 		for i, value := range maxMags {
 			if value > avg {
-				peakTimeInBin := freqIndices[i] * binDuration / float64(len(bin))
+				peakTime := float64(frameIdx) * frameDuration
+				peakFreq := float64(freqIndices[i]) * freqResolution
 
-				// Calculate the absolute time of the peak
+				peaks = append(peaks, Peak{Time: peakTime, Freq: peakFreq})
-				peakTime := float64(binIdx)*binDuration + peakTimeInBin
-
-				peaks = append(peaks, Peak{Time: peakTime, Freq: maxFreqs[i]})
 			}
 		}
 	}

server/spotify/downloader.go

@@ -2,9 +2,7 @@ package spotify
 
 import (
 	"context"
-	"errors"
 	"fmt"
-	"io"
 	"log/slog"
 	"os"
 	"os/exec"
@@ -13,17 +11,15 @@ import (
 	"song-recognition/db"
 	"song-recognition/shazam"
 	"song-recognition/utils"
-	"song-recognition/wav"
 	"strings"
 	"sync"
 	"time"
 
 	"github.com/fatih/color"
-	"github.com/kkdai/youtube/v2"
 	"github.com/mdobak/go-xerrors"
 )
 
-const DELETE_SONG_FILE = false
+const DELETE_SONG_FILE = false // Set true to delete the song file after fingerprinting
 
 var yellow = color.New(color.FgYellow)
 
@@ -135,9 +131,9 @@ func dlTrack(tracks []Track, path string) (int, error) {
 
 			trackCopy.Title, trackCopy.Artist = correctFilename(trackCopy.Title, trackCopy.Artist)
 			fileName := fmt.Sprintf("%s - %s", trackCopy.Title, trackCopy.Artist)
-			filePath := filepath.Join(path, fileName+".m4a")
+			filePath := filepath.Join(path, fileName)
 
-			err = downloadYTaudio(ytID, path, filePath)
+			filePath, err = downloadYTaudio(ytID, filePath)
 			if err != nil {
 				logMessage := fmt.Sprintf("'%s' by '%s' could not be downloaded", trackCopy.Title, trackCopy.Artist)
 				logger.ErrorContext(ctx, logMessage, slog.Any("error", xerrors.New(err)))
@@ -151,12 +147,10 @@ func dlTrack(tracks []Track, path string) (int, error) {
 				return
 			}
 
-			utils.DeleteFile(filepath.Join(path, fileName+".m4a"))
-
 			wavFilePath := filepath.Join(path, fileName+".wav")
 
 			if err := addTags(wavFilePath, *trackCopy); err != nil {
-				logMessage := fmt.Sprintf("Error adding tags: %s", filePath+".wav")
+				logMessage := fmt.Sprintf("Error adding tags: %s", wavFilePath)
 				logger.ErrorContext(ctx, logMessage, slog.Any("error", xerrors.New(err)))
 
 				return
@@ -186,65 +180,6 @@ func dlTrack(tracks []Track, path string) (int, error) {
 
 }
 
-/* github.com/kkdai/youtube */
-func downloadYTaudio(id, path, filePath string) error {
-	logger := utils.GetLogger()
-	dir, err := os.Stat(path)
-	if err != nil {
-		logger.Error("Error accessing path", slog.Any("error", err))
-		return err
-	}
-
-	if !dir.IsDir() {
-		err := errors.New("the path is not valid (not a dir)")
-		logger.Error("Invalid directory path", slog.Any("error", err))
-		return err
-	}
-
-	client := youtube.Client{}
-	video, err := client.GetVideo(id)
-	if err != nil {
-		logger.Error("Error getting YouTube video", slog.Any("error", err))
-		return err
-	}
-
-	/*
-		itag code: 140, container: m4a, content: audio, bitrate: 128k
-		change the FindByItag parameter to 139 if you want smaller files (but with a bitrate of 48k)
-		https://gist.github.com/sidneys/7095afe4da4ae58694d128b1034e01e2
-	*/
-	formats := video.Formats.Itag(140)
-
-	/* in some cases, when attempting to download the audio
-	using the library github.com/kkdai/youtube,
-	the download fails (and shows the file size as 0 bytes)
-	until the second or third attempt. */
-	var fileSize int64
-	file, err := os.Create(filePath)
-	if err != nil {
-		logger.Error("Error creating file", slog.Any("error", err))
-		return err
-	}
-
-	for fileSize == 0 {
-		stream, _, err := client.GetStream(video, &formats[0])
-		if err != nil {
-			logger.Error("Error getting stream", slog.Any("error", err))
-			return err
-		}
-
-		if _, err = io.Copy(file, stream); err != nil {
-			logger.Error("Error copying stream to file", slog.Any("error", err))
-			return err
-		}
-
-		fileSize, _ = GetFileSize(filePath)
-	}
-	defer file.Close()
-
-	return nil
-}
-
 func addTags(file string, track Track) error {
 	logger := utils.GetLogger()
 	// Create a temporary file name by appending "2" before the extension
@@ -255,7 +190,7 @@ func addTags(file string, track Track) error {
 		tempFile = baseName + "2" + ".wav" // Temporary filename ('/path/to/title - artist2.wav')
 	}
 
-	// Execute FFmpeg command to add metadata tags
+	// FFmpeg command to add metadata tags
 	cmd := exec.Command(
 		"ffmpeg",
 		"-i", file, // Input file path
@@ -291,40 +226,20 @@ func ProcessAndSaveSong(songFilePath, songTitle, songArtist, ytID string) error
 	}
 	defer dbclient.Close()
 
-	wavFilePath, err := wav.ConvertToWAV(songFilePath, 1)
-	if err != nil {
-		logger.Error("Failed to convert to WAV", slog.Any("error", err))
-		return err
-	}
-
-	wavInfo, err := wav.ReadWavInfo(wavFilePath)
-	if err != nil {
-		logger.Error("Failed to read WAV info", slog.Any("error", err))
-		return err
-	}
-
-	samples, err := wav.WavBytesToSamples(wavInfo.Data)
-	if err != nil {
-		logger.Error("Error converting WAV bytes to samples", slog.Any("error", err))
-		return fmt.Errorf("error converting wav bytes to float64: %v", err)
-	}
-
-	spectro, err := shazam.Spectrogram(samples, wavInfo.SampleRate)
-	if err != nil {
-		logger.Error("Error creating spectrogram", slog.Any("error", err))
-		return fmt.Errorf("error creating spectrogram: %v", err)
-	}
-
 	songID, err := dbclient.RegisterSong(songTitle, songArtist, ytID)
 	if err != nil {
 		logger.Error("Failed to register song", slog.Any("error", err))
-		return err
+		return fmt.Errorf("error registering song '%s' by '%s': %v", songTitle, songArtist, err)
 	}
 
-	peaks := shazam.ExtractPeaks(spectro, wavInfo.Duration)
+	fingerprint, err := shazam.FingerprintAudio(songFilePath, songID)
-	fingerprints := shazam.Fingerprint(peaks, songID)
+	if err != nil {
+		dbclient.DeleteSongByID(songID)
+		logger.Error("Failed to create fingerprint", slog.String("wavFilePath", songFilePath))
+		return fmt.Errorf("error generating fingerprint for %s by %s", songTitle, songArtist)
+	}
 
-	err = dbclient.StoreFingerprints(fingerprints)
+	err = dbclient.StoreFingerprints(fingerprint)
 	if err != nil {
 		dbclient.DeleteSongByID(songID)
 		logger.Error("Failed to store fingerprints", slog.Any("error", err))

server/spotify/youtube.go

@@ -4,6 +4,11 @@ import (
 	"context"
 	"fmt"
 	"log"
+	"log/slog"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"song-recognition/utils"
 
 	"errors"
 	"io"
@@ -215,3 +220,37 @@ func ytSearch(searchTerm string, limit int) (results []*SearchResult, err error)
 
 	return results, nil
 }
+
+// downloadYTaudio downloads audio from a YouTube video using yt-dlp command line tool.
+func downloadYTaudio(videoURL, outputFilePath string) (string, error) {
+	logger := utils.GetLogger()
+
+	dir := filepath.Dir(outputFilePath)
+	if stat, err := os.Stat(dir); err != nil || !stat.IsDir() {
+		logger.Error("Invalid directory for output file", slog.Any("error", err))
+		return "", errors.New("output directory does not exist or is not a directory")
+	}
+
+	_, err := exec.LookPath("yt-dlp")
+	if err != nil {
+		logger.Error("yt-dlp not found in PATH", slog.Any("error", err))
+		return "", errors.New("yt-dlp is not installed or not in PATH")
+	}
+
+	audioFmt := "wav"
+	cmd := exec.Command(
+		"yt-dlp",
+		"-f", "bestaudio",
+		"--extract-audio",
+		"--audio-format", audioFmt,
+		"-o", outputFilePath,
+		videoURL,
+	)
+
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		logger.Error("yt-dlp command failed", slog.String("output", string(output)), slog.Any("error", err))
+		return "", err
+	}
+	return outputFilePath + "." + audioFmt, nil
+}

server/utils/utils.go

@@ -27,3 +27,9 @@ func GetEnv(key string, fallback ...string) string {
 	}
 	return ""
 }
+
+func ExtendMap[K comparable, V any](dest, src map[K]V) {
+	for k, v := range src {
+		dest[k] = v
+	}
+}

server/wasm/wasm_main.go

@@ -1,64 +0,0 @@
-//go:build js && wasm
-// +build js,wasm
-
-package main
-
-import (
-	"song-recognition/shazam"
-	"song-recognition/utils"
-	"syscall/js"
-)
-
-func generateFingerprint(this js.Value, args []js.Value) interface{} {
-	if len(args) < 2 {
-		return js.ValueOf(map[string]interface{}{
-			"error": 1,
-			"data":  "Expected audio array and sample rate",
-		})
-	}
-
-	if args[0].Type() != js.TypeObject || args[1].Type() != js.TypeNumber {
-		return js.ValueOf(map[string]interface{}{
-			"error": 2,
-			"data":  "Invalid argument types; Expected audio array and samplerate (type: int)",
-		})
-	}
-
-	inputArray := args[0]
-	sampleRate := args[1].Int()
-
-	audioData := make([]float64, inputArray.Length())
-	for i := 0; i < inputArray.Length(); i++ {
-		audioData[i] = inputArray.Index(i).Float()
-	}
-
-	spectrogram, err := shazam.Spectrogram(audioData, sampleRate)
-	if err != nil {
-		return js.ValueOf(map[string]interface{}{
-			"error": 3,
-			"data":  "Error generating spectrogram: " + err.Error(),
-		})
-	}
-
-	peaks := shazam.ExtractPeaks(spectrogram, float64(len(audioData)/sampleRate))
-	fingerprint := shazam.Fingerprint(peaks, utils.GenerateUniqueID())
-
-	fingerprintArray := []interface{}{}
-	for address, couple := range fingerprint {
-		entry := map[string]interface{}{
-			"address":    address,
-			"anchorTime": couple.AnchorTimeMs,
-		}
-		fingerprintArray = append(fingerprintArray, entry)
-	}
-
-	return js.ValueOf(map[string]interface{}{
-		"error": 0,
-		"data":  fingerprintArray,
-	})
-}
-
-func main() {
-	js.Global().Set("generateFingerprint", js.FuncOf(generateFingerprint))
-	select {}
-}

server/wav/convert.go

@@ -6,21 +6,33 @@ import (
 	"os/exec"
 	"path/filepath"
 	"song-recognition/utils"
+	"strconv"
 	"strings"
 )
 
 // ConvertToWAV converts an input audio file to WAV format with specified channels.
-func ConvertToWAV(inputFilePath string, channels int) (wavFilePath string, err error) {
+func ConvertToWAV(inputFilePath string) (wavFilePath string, err error) {
 	_, err = os.Stat(inputFilePath)
 	if err != nil {
 		return "", fmt.Errorf("input file does not exist: %v", err)
 	}
 
-	if channels < 1 || channels > 2 {
+	to_stereoStr := utils.GetEnv("FINGERPRINT_STEREO", "false")
-		channels = 1
+	to_stereo, err := strconv.ParseBool(to_stereoStr)
+	if err != nil {
+		return "", fmt.Errorf("failed to convert env variable (%s) to bool: %v", "FINGERPRINT_STEREO", err)
+	}
+
+	channels := 1
+	if to_stereo {
+		channels = 2
 	}
 
 	fileExt := filepath.Ext(inputFilePath)
+	if fileExt != ".wav" {
+		defer os.Remove(inputFilePath)
+	}
+
 	outputFile := strings.TrimSuffix(inputFilePath, fileExt) + ".wav"
 
 	// Output file may already exists. If it does FFmpeg will fail as

server/wav/wav.go

@@ -94,49 +94,83 @@ func WriteWavFile(filename string, data []byte, sampleRate int, channels int, bi
 	return err
 }
 
-// WavInfo defines a struct containing information extracted from the WAV header
 type WavInfo struct {
-	Channels   int
+	Channels            int
-	SampleRate int
+	SampleRate          int
-	Data       []byte
+	Duration            float64
-	Duration   float64
+	Data                []byte
+	LeftChannelSamples  []float64
+	RightChannelSamples []float64
 }
 
+// ReadWavInfo reads a 16-bit PCM WAV file and returns its metadata and audio samples.
+// Supports mono and stereo files. Note that it only supports 16-bit PCM format.
 func ReadWavInfo(filename string) (*WavInfo, error) {
 	data, err := ioutil.ReadFile(filename)
 	if err != nil {
 		return nil, err
 	}
-
 	if len(data) < 44 {
 		return nil, errors.New("invalid WAV file size (too small)")
 	}
 
-	// Read header chunks
+	// Parse PCM header to extract metadata
+	// https://en.wikipedia.org/wiki/WAV#WAV_file_header
 	var header WavHeader
-	err = binary.Read(bytes.NewReader(data[:44]), binary.LittleEndian, &header)
+	if err := binary.Read(bytes.NewReader(data[:44]), binary.LittleEndian, &header); err != nil {
-	if err != nil {
 		return nil, err
 	}
-
+	if string(header.ChunkID[:]) != "RIFF" ||
-	if string(header.ChunkID[:]) != "RIFF" || string(header.Format[:]) != "WAVE" || header.AudioFormat != 1 {
+		string(header.Format[:]) != "WAVE" ||
+		header.AudioFormat != 1 {
 		return nil, errors.New("invalid WAV header format")
 	}
 
-	// Extract information
 	info := &WavInfo{
 		Channels:   int(header.NumChannels),
 		SampleRate: int(header.SampleRate),
 		Data:       data[44:],
 	}
 
-	// Calculate audio duration (assuming data contains PCM data)
+	if header.BitsPerSample != 16 {
-	if header.BitsPerSample == 16 {
+		return nil, errors.New("unsupported bits‑per‑sample (expect 16‑bit PCM)")
-		info.Duration = float64(len(info.Data)) / float64(int(header.NumChannels)*2*int(header.SampleRate))
-	} else {
-		return nil, errors.New("unsupported bits per sample format")
 	}
 
+	sampleCount := len(info.Data) / 2
+	int16Buf := make([]int16, sampleCount)
+	if err := binary.Read(bytes.NewReader(info.Data), binary.LittleEndian, int16Buf); err != nil {
+		return nil, err
+	}
+
+	const scale = 1.0 / 32768.0 // 16‑bit normalisation factor
+
+	switch header.NumChannels {
+	case 1:
+		left := make([]float64, sampleCount)
+		for i, s := range int16Buf {
+			left[i] = float64(s) * scale
+		}
+		info.LeftChannelSamples = left
+
+	case 2:
+		frameCount := sampleCount / 2
+		left := make([]float64, frameCount)
+		right := make([]float64, frameCount)
+		for i := 0; i < frameCount; i++ {
+			left[i] = float64(int16Buf[2*i]) * scale
+			right[i] = float64(int16Buf[2*i+1]) * scale
+		}
+		info.LeftChannelSamples = left
+		info.RightChannelSamples = right
+
+	default:
+		return nil, errors.New("unsupported channel count (only mono/stereo)")
+	}
+
+	// Compute audio duration in seconds
+	info.Duration = float64(sampleCount) /
+		(float64(header.NumChannels) * float64(header.SampleRate))
+
 	return info, nil
 }
 

wasm/build.sh

@@ -0,0 +1,22 @@
+#!/bin/bash
+
+# Build script for WASM fingerprint generator
+
+echo "Building WASM module..."
+
+export GOOS=js
+export GOARCH=wasm
+
+go build -o fingerprint.wasm wasm_main.go
+
+if [ $? -eq 0 ]; then
+    echo "✓ WASM build successful: fingerprint.wasm"
+    
+    cp fingerprint.wasm ../client/public/
+    echo "✓ Copied fingerprint.wasm to client/public/"
+
+else
+    echo "x WASM build failed"
+    cd ../wasm
+    exit 1
+fi

wasm/go.mod

@@ -0,0 +1,25 @@
+module wasm-fingerprint
+
+go 1.23.0
+
+toolchain go1.24.3
+
+require song-recognition v0.0.0-00010101000000-000000000000
+
+require (
+	github.com/golang/snappy v0.0.4 // indirect
+	github.com/klauspost/compress v1.17.6 // indirect
+	github.com/mattn/go-sqlite3 v1.14.22 // indirect
+	github.com/mdobak/go-xerrors v0.3.1 // indirect
+	github.com/montanaflynn/stats v0.7.1 // indirect
+	github.com/xdg-go/pbkdf2 v1.0.0 // indirect
+	github.com/xdg-go/scram v1.1.2 // indirect
+	github.com/xdg-go/stringprep v1.0.4 // indirect
+	github.com/youmark/pkcs8 v0.0.0-20201027041543-1326539a0a0a // indirect
+	go.mongodb.org/mongo-driver v1.14.0 // indirect
+	golang.org/x/crypto v0.33.0 // indirect
+	golang.org/x/sync v0.11.0 // indirect
+	golang.org/x/text v0.22.0 // indirect
+)
+
+replace song-recognition => ../server

wasm/go.sum

@@ -0,0 +1,59 @@
+github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc h1:U9qPSI2PIWSS1VwoXQT9A3Wy9MM3WgvqSxFWenqJduM=
+github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/golang/snappy v0.0.4 h1:yAGX7huGHXlcLOEtBnF4w7FQwA26wojNCwOYAEhLjQM=
+github.com/golang/snappy v0.0.4/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
+github.com/google/go-cmp v0.5.2 h1:X2ev0eStA3AbceY54o37/0PQ/UWqKEiiO2dKL5OPaFM=
+github.com/google/go-cmp v0.5.2/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/klauspost/compress v1.17.6 h1:60eq2E/jlfwQXtvZEeBUYADs+BwKBWURIY+Gj2eRGjI=
+github.com/klauspost/compress v1.17.6/go.mod h1:/dCuZOvVtNoHsyb+cuJD3itjs3NbnF6KH9zAO4BDxPM=
+github.com/mattn/go-sqlite3 v1.14.22 h1:2gZY6PC6kBnID23Tichd1K+Z0oS6nE/XwU+Vz/5o4kU=
+github.com/mattn/go-sqlite3 v1.14.22/go.mod h1:Uh1q+B4BYcTPb+yiD3kU8Ct7aC0hY9fxUwlHK0RXw+Y=
+github.com/mdobak/go-xerrors v0.3.1 h1:XfqaLMNN5T4qsHSlLHGJ35f6YlDTVeINSYYeeuK4VpQ=
+github.com/mdobak/go-xerrors v0.3.1/go.mod h1:nIR+HMAJuj/uNqyp5+MTN6PJ7ymuIJq3UVs9QCgAHbY=
+github.com/montanaflynn/stats v0.7.1 h1:etflOAAHORrCC44V+aR6Ftzort912ZU+YLiSTuV8eaE=
+github.com/montanaflynn/stats v0.7.1/go.mod h1:etXPPgVO6n31NxCd9KQUMvCM+ve0ruNzt6R8Bnaayow=
+github.com/xdg-go/pbkdf2 v1.0.0 h1:Su7DPu48wXMwC3bs7MCNG+z4FhcyEuz5dlvchbq0B0c=
+github.com/xdg-go/pbkdf2 v1.0.0/go.mod h1:jrpuAogTd400dnrH08LKmI/xc1MbPOebTwRqcT5RDeI=
+github.com/xdg-go/scram v1.1.2 h1:FHX5I5B4i4hKRVRBCFRxq1iQRej7WO3hhBuJf+UUySY=
+github.com/xdg-go/scram v1.1.2/go.mod h1:RT/sEzTbU5y00aCK8UOx6R7YryM0iF1N2MOmC3kKLN4=
+github.com/xdg-go/stringprep v1.0.4 h1:XLI/Ng3O1Atzq0oBs3TWm+5ZVgkq2aqdlvP9JtoZ6c8=
+github.com/xdg-go/stringprep v1.0.4/go.mod h1:mPGuuIYwz7CmR2bT9j4GbQqutWS1zV24gijq1dTyGkM=
+github.com/youmark/pkcs8 v0.0.0-20201027041543-1326539a0a0a h1:fZHgsYlfvtyqToslyjUt3VOPF4J7aK/3MPcK7xp3PDk=
+github.com/youmark/pkcs8 v0.0.0-20201027041543-1326539a0a0a/go.mod h1:ul22v+Nro/R083muKhosV54bj5niojjWZvU8xrevuH4=
+github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
+go.mongodb.org/mongo-driver v1.14.0 h1:P98w8egYRjYe3XDjxhYJagTokP/H6HzlsnojRgZRd80=
+go.mongodb.org/mongo-driver v1.14.0/go.mod h1:Vzb0Mk/pa7e6cWw85R4F/endUC3u0U9jGcNU603k65c=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20200302210943-78000ba7a073/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
+golang.org/x/crypto v0.33.0 h1:IOBPskki6Lysi0lo9qQvbxiQ+FvsCC/YWOecCHAixus=
+golang.org/x/crypto v0.33.0/go.mod h1:bVdXmD7IV/4GdElGPozy6U7lWdRXA4qyRVGJV57uQ5M=
+golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
+golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
+golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.11.0 h1:GGz8+XQP4FvTTrjZPzNKTMFtSXH80RAzG+5ghFPgK9w=
+golang.org/x/sync v0.11.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
+golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
+golang.org/x/text v0.3.8/go.mod h1:E6s5w1FMmriuDzIBO73fBruAKo1PCIq6d2Q6DHfQ8WQ=
+golang.org/x/text v0.22.0 h1:bofq7m3/HAFvbF51jz3Q9wLg3jkvSPuiZu/pD1XwgtM=
+golang.org/x/text v0.22.0/go.mod h1:YRoo4H8PVmsu+E3Ou7cqLVH8oXWIHVoX0jqUWALQhfY=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
+golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

wasm/wasm_main.go

@@ -0,0 +1,111 @@
+//go:build js && wasm
+// +build js,wasm
+
+package main
+
+import (
+	"song-recognition/models"
+	"song-recognition/shazam"
+	"song-recognition/utils"
+	"syscall/js"
+)
+
+// generateFingerprint takes audio data from the frontend and generates fingerprints
+// Arguments: [audioArray, sampleRate, channels]
+// Returns: { error: number, data: fingerprintArray or error message }
+func generateFingerprint(this js.Value, args []js.Value) interface{} {
+	if len(args) < 3 {
+		return js.ValueOf(map[string]interface{}{
+			"error": 1,
+			"data":  "Expected audio array, sample rate, and number of channels",
+		})
+	}
+
+	if args[0].Type() != js.TypeObject || args[1].Type() != js.TypeNumber {
+		return js.ValueOf(map[string]interface{}{
+			"error": 2,
+			"data":  "Invalid argument types; Expected audio array and samplerate (type: int)",
+		})
+	}
+
+	channels := args[2].Int()
+	if args[2].Type() != js.TypeNumber || (channels != 1 && channels != 2) {
+		return js.ValueOf(map[string]interface{}{
+			"error": 2,
+			"data":  "Invalid number of channels; expected 1 or 2",
+		})
+	}
+
+	inputArray := args[0]
+	sampleRate := args[1].Int()
+
+	audioData := make([]float64, inputArray.Length())
+	for i := 0; i < inputArray.Length(); i++ {
+		audioData[i] = inputArray.Index(i).Float()
+	}
+
+	fingerprint := make(map[uint32]models.Couple)
+	var leftChannel, rightChannel []float64
+
+	if channels == 1 {
+		leftChannel = audioData
+		spectrogram, err := shazam.Spectrogram(audioData, sampleRate)
+		if err != nil {
+			return js.ValueOf(map[string]interface{}{
+				"error": 3,
+				"data":  "Error generating spectrogram: " + err.Error(),
+			})
+		}
+		peaks := shazam.ExtractPeaks(spectrogram, float64(len(audioData))/float64(sampleRate), sampleRate)
+		fingerprint = shazam.Fingerprint(peaks, utils.GenerateUniqueID())
+	} else {
+		for i := 0; i < len(audioData); i += 2 {
+			leftChannel = append(leftChannel, audioData[i])
+			rightChannel = append(rightChannel, audioData[i+1])
+		}
+
+		// LEFT
+		spectrogram, err := shazam.Spectrogram(leftChannel, sampleRate)
+		if err != nil {
+			return js.ValueOf(map[string]interface{}{
+				"error": 3,
+				"data":  "Error generating spectrogram: " + err.Error(),
+			})
+		}
+		peaks := shazam.ExtractPeaks(spectrogram, float64(len(leftChannel))/float64(sampleRate), sampleRate)
+		utils.ExtendMap(fingerprint, shazam.Fingerprint(peaks, utils.GenerateUniqueID()))
+
+		// RIGHT
+		spectrogram, err = shazam.Spectrogram(rightChannel, sampleRate)
+		if err != nil {
+			return js.ValueOf(map[string]interface{}{
+				"error": 3,
+				"data":  "Error generating spectrogram: " + err.Error(),
+			})
+		}
+		peaks = shazam.ExtractPeaks(spectrogram, float64(len(rightChannel))/float64(sampleRate), sampleRate)
+		utils.ExtendMap(fingerprint, shazam.Fingerprint(peaks, utils.GenerateUniqueID()))
+	}
+
+	fingerprintArray := []interface{}{}
+	for address, couple := range fingerprint {
+		entry := map[string]interface{}{
+			"address":    address,
+			"anchorTime": couple.AnchorTimeMs,
+		}
+		fingerprintArray = append(fingerprintArray, entry)
+	}
+
+	return js.ValueOf(map[string]interface{}{
+		"error": 0,
+		"data":  fingerprintArray,
+	})
+}
+
+func main() {
+	js.Global().Set("generateFingerprint", js.FuncOf(generateFingerprint))
+
+	js.Global().Call("dispatchEvent", js.Global().Get("Event").New("wasmReady"))
+
+	select {}
+}