remove gjson dependency

probe_test.go

@@ -1,14 +1,39 @@
 package ffmpeg_go
 
 import (
+	"encoding/json"
+	"fmt"
+	"strconv"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
-	"github.com/tidwall/gjson"
 )
 
 func TestProbe(t *testing.T) {
 	data, err := Probe(TestInputFile1, nil)
 	assert.Nil(t, err)
-	assert.Equal(t, gjson.Get(data, "format.duration").String(), "7.036000")
+	duration, err := probeOutputDuration(data)
+	assert.Nil(t, err)
+	assert.Equal(t, fmt.Sprintf("%f", duration), "7.036000")
+}
+
+type probeFormat struct {
+	Duration string `json:"duration"`
+}
+
+type probeData struct {
+	Format probeFormat `json:"format"`
+}
+
+func probeOutputDuration(a string) (float64, error) {
+	pd := probeData{}
+	err := json.Unmarshal([]byte(a), &pd)
+	if err != nil {
+		return 0, err
+	}
+	f, err := strconv.ParseFloat(pd.Format.Duration, 64)
+	if err != nil {
+		return 0, err
+	}
+	return f, nil
 }