diff --git a/backend/pkg/utils/ffmpeg.go b/backend/pkg/utils/ffmpeg.go
index b96cddb..310a627 100644
--- a/backend/pkg/utils/ffmpeg.go
+++ b/backend/pkg/utils/ffmpeg.go
@@ -22,16 +22,16 @@ func GetMediaDuration(path string) (int64, error) {
 	}
 	duration := string(durationOutput)
 	duration = strings.TrimSpace(duration)
-	durationInt, err := strconv.Atoi(duration)
+	durationFloat, err := strconv.ParseFloat(duration, 64)
 	if err != nil {
 		return 0, errors.Wrap(err, "duration conversion error")
 	}
-	return int64(durationInt), nil
+	return int64(durationFloat), nil
 }
 
 func CutMedia(input, output string, start, end int64) error {
 	//  ffmpeg -ss 00:00:00 -i input.mp4 -to 00:01:00 -c copy output.mp4
-	cmd := exec.Command("ffmpeg", "-ss", strconv.FormatInt(start, 10), "-i", input, "-t", strconv.FormatInt(end, 10), "-c", "copy", output)
+	cmd := exec.Command("ffmpeg", "-y", "-ss", strconv.FormatInt(start, 10), "-i", input, "-t", strconv.FormatInt(end, 10), "-c", "copy", output)
 
 	stdout, err := cmd.StdoutPipe()
 	if err != nil {
@@ -81,8 +81,8 @@ func CutMedia(input, output string, start, end int64) error {
 
 // GetFrameImageFromVideo extracts target time frame from a video file and saves it as an image.
 func GetFrameImageFromVideo(input, output string, time int64) error {
-	// ffmpeg -i input.mp4 -ss 00:00:01 -vframes 1 output.jpg
-	cmd := exec.Command("ffmpeg", "-i", input, "-ss", strconv.FormatInt(time, 10), "-vframes", "1", output)
+	// ffmpeg -y -i input.mp4 -ss 00:00:01 -vframes 1 output.jpg
+	cmd := exec.Command("ffmpeg", "-y", "-i", input, "-ss", strconv.FormatInt(time, 10), "-vframes", "1", output)
 	stdout, err := cmd.StdoutPipe()
 	if err != nil {
 		return errors.Wrap(err, "stdout pipe error")
diff --git a/backend/pkg/utils/ffmpeg_test.go b/backend/pkg/utils/ffmpeg_test.go
new file mode 100644
index 0000000..b99665c
--- /dev/null
+++ b/backend/pkg/utils/ffmpeg_test.go
@@ -0,0 +1,49 @@
+package utils
+
+import (
+	"path/filepath"
+	"testing"
+
+	"github.com/rogeecn/fabfile"
+	. "github.com/smartystreets/goconvey/convey"
+)
+
+func Test_GetMediaDuration(t *testing.T) {
+	Convey("test_get_media_duration", t, func() {
+		target := fabfile.MustFind("fixtures/input.mp4")
+		duration, err := GetMediaDuration(target)
+		So(err, ShouldBeNil)
+		t.Logf("duration is: %d", duration)
+	})
+}
+
+func Test_CutMedia(t *testing.T) {
+	Convey("test_cut_media", t, func() {
+		input := fabfile.MustFind("fixtures/input.mp4")
+		output := fabfile.MustFind("fixtures/output.mp4")
+
+		t.Logf("INPUT: %s", input)
+		t.Logf("OUTPUT: %s", output)
+
+		err := CutMedia(input, output, 0, 10)
+		So(err, ShouldBeNil)
+
+		// check output duration
+		duration, err := GetMediaDuration(output)
+		So(err, ShouldBeNil)
+		t.Logf("output duration is: %d", duration)
+	})
+}
+
+func Test_GetFrameImageFromVideo(t *testing.T) {
+	Convey("test_get_frame_image_from_video", t, func() {
+		input := fabfile.MustFind("fixtures/input.mp4")
+		output := filepath.Join(filepath.Dir(input), "output.jpg")
+
+		t.Logf("INPUT: %s", input)
+		t.Logf("OUTPUT: %s", output)
+
+		err := GetFrameImageFromVideo(input, output, 1)
+		So(err, ShouldBeNil)
+	})
+}