support for homebrew ffmpeg on macos (#561)

* support for homebrew ffmpeg on macos

* Add build instructions

* Revise README

---------

Co-authored-by: afkarxyz <mzamzamafkarhadiq@gmail.com>

backend/ffmpeg.go

@@ -81,6 +81,28 @@ func GetFFmpegPath() (string, error) {
 		return localPath, nil
 	}
 
+	if runtime.GOOS == "darwin" && runtime.GOARCH == "arm64" {
+		homebrewPath := "/opt/homebrew/bin/" + ffmpegName
+		if _, err := os.Stat(homebrewPath); err == nil {
+			return homebrewPath, nil
+		}
+	} else if runtime.GOOS == "darwin" && runtime.GOARCH == "amd64" {
+		homebrewPath := "/usr/local/bin/" + ffmpegName
+		if _, err := os.Stat(homebrewPath); err == nil {
+			return homebrewPath, nil
+		}
+	}
+
+	if runtime.GOOS != "windows" {
+		path, err := exec.Command("which", ffmpegName).Output()
+		if err == nil {
+			trimmed := strings.TrimSpace(string(path))
+			if trimmed != "" {
+				return trimmed, nil
+			}
+		}
+	}
+
 	path, err := exec.LookPath(ffmpegName)
 	if err == nil {
 		return path, nil
@@ -105,6 +127,28 @@ func GetFFprobePath() (string, error) {
 		return localPath, nil
 	}
 
+	if runtime.GOOS == "darwin" && runtime.GOARCH == "arm64" {
+		homebrewPath := "/opt/homebrew/bin/" + ffprobeName
+		if _, err := os.Stat(homebrewPath); err == nil {
+			return homebrewPath, nil
+		}
+	} else if runtime.GOOS == "darwin" && runtime.GOARCH == "amd64" {
+		homebrewPath := "/usr/local/bin/" + ffprobeName
+		if _, err := os.Stat(homebrewPath); err == nil {
+			return homebrewPath, nil
+		}
+	}
+
+	if runtime.GOOS != "windows" {
+		path, err := exec.Command("which", ffprobeName).Output()
+		if err == nil {
+			trimmed := strings.TrimSpace(string(path))
+			if trimmed != "" {
+				return trimmed, nil
+			}
+		}
+	}
+
 	path, err := exec.LookPath(ffprobeName)
 	if err == nil {
 		return path, nil