diff --git a/main.go b/main.go
index a372ca5..06cf2f4 100644
--- a/main.go
+++ b/main.go
@@ -2,7 +2,9 @@ package main
 
 import (
 	"flag"
+	"image"
 	"image/jpeg"
+	"image/png"
 	"os"
 	"path/filepath"
 	"sync"
@@ -14,6 +16,7 @@ import (
 
 func main() {
 	thresh := flag.Int("thresh", 10, "Threshold for distance")
+	workers := flag.Int("workers", 100, "Number of workers")
 	flag.Parse()
 	logger.InitFlag()
 	hashes := &sync.Map{}
@@ -39,11 +42,14 @@ func main() {
 	}
 	logger.Info("Patterns expanded to %d files", len(files))
 
+	workerChan := make(chan struct{}, *workers)
 	wg := sync.WaitGroup{}
 	for _, file := range files {
+		workerChan <- struct{}{}
 		wg.Add(1)
 		go func(file string) {
 			defer wg.Done()
+			defer func() { <-workerChan }()
 			log := logger.Default.WithPrefix(file)
 			ext := filepath.Ext(file)
 			if ext != ".jpg" && ext != ".jpeg" && ext != ".png" {
@@ -57,11 +63,19 @@ func main() {
 				return
 			}
 			defer imgfile.Close()
-			img, err := jpeg.Decode(imgfile)
+
+			isPng := ext == ".png"
+			var img image.Image
+			if isPng {
+				img, err = png.Decode(imgfile)
+			} else {
+				img, err = jpeg.Decode(imgfile)
+			}
 			if err != nil {
 				log.Error("Failed to decode image: %v", err)
 				return
 			}
+
 			hash, err := goimagehash.ExtPerceptionHash(img, 8, 8)
 			if err != nil {
 				log.Error("Failed to calculate hash: %v", err)
@@ -75,41 +89,48 @@ func main() {
 	groupedImages := make(map[string][]string)
 	wg.Wait()
 
-	processed := make(map[string]bool)
+	processed := &sync.Map{}
 	hashes.Range(func(key, value interface{}) bool {
-		filea := key.(string)
-		hasha := value.(*goimagehash.ExtImageHash)
+		workerChan <- struct{}{}
+		wg.Add(1)
+		go func(key, value interface{}) {
+			defer wg.Done()
+			defer func() { <-workerChan }()
+			filea := key.(string)
+			hasha := value.(*goimagehash.ExtImageHash)
 
-		if processed[filea] {
-			return true
-		}
+			if _, ok := processed.Load(filea); ok {
+				return
+			}
 
-		var group []string
-		hashes.Range(func(key, value interface{}) bool {
-			fileb := key.(string)
-			hashb := value.(*goimagehash.ExtImageHash)
-			if filea == fileb {
+			var group []string
+			hashes.Range(func(key, value interface{}) bool {
+				fileb := key.(string)
+				hashb := value.(*goimagehash.ExtImageHash)
+				if filea == fileb {
+					return true
+				}
+				distance, err := hasha.Distance(hashb)
+				if err != nil {
+					logger.Error("Failed to calculate distance: %v", err)
+					return true
+				}
+				logger.Debug("Distance between %v and %v: %v", filea, fileb, distance)
+				if distance <= *thresh {
+					group = append(group, fileb)
+					processed.Store(fileb, true)
+				}
 				return true
-			}
-			distance, err := hasha.Distance(hashb)
-			if err != nil {
-				logger.Error("Failed to calculate distance: %v", err)
-				return true
-			}
-			logger.Debug("Distance between %v and %v: %v", filea, fileb, distance)
-			if distance <= *thresh {
-				group = append(group, fileb)
-				processed[fileb] = true
-			}
-			return true
-		})
+			})
 
-		if len(group) > 0 {
-			groupedImages[filea] = group
-			processed[filea] = true
-		}
+			if len(group) > 0 {
+				groupedImages[filea] = group
+				processed.Store(filea, true)
+			}
+		}(key, value)
 		return true
 	})
+	wg.Wait()
 
 	// Deduplicate by keeping the largest file in each group
 	for file, group := range groupedImages {