add example showProgress

examples/showProgress.go

@@ -0,0 +1,83 @@
+package examples
+
+import (
+	"fmt"
+	"log"
+	"math/rand"
+	"net"
+	"os"
+	"path"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/tidwall/gjson"
+	ffmpeg "github.com/u2takey/ffmpeg-go"
+)
+
+// ExampleShowProgess is an example of using the ffmpeg `-progress` option with a
+//    unix-domain socket to report progress
+func ExampleShowProgess(inFileName, outFileName string) {
+	a, err := ffmpeg.Probe(inFileName)
+	if err != nil {
+		panic(err)
+	}
+	totalDuration := gjson.Get(a, "format.duration").Float()
+
+	err = ffmpeg.Input(inFileName).
+		Output(outFileName, ffmpeg.KwArgs{"c:v": "libx264", "preset": "veryslow"}).
+		GlobalArgs("-progress", "unix://"+TempSock(totalDuration)).
+		OverWriteOutput().
+		Run()
+	if err != nil {
+		panic(err)
+	}
+}
+
+func TempSock(totalDuration float64) string {
+	// serve
+
+	rand.Seed(time.Now().Unix())
+	sockFileName := path.Join(os.TempDir(), fmt.Sprintf("%d_sock", rand.Int()))
+	l, err := net.Listen("unix", sockFileName)
+	if err != nil {
+		panic(err)
+	}
+
+	go func() {
+		re := regexp.MustCompile(`out_time_ms=(\d+)`)
+		fd, err := l.Accept()
+		if err != nil {
+			log.Fatal("accept error:", err)
+		}
+		buf := make([]byte, 16)
+		data := ""
+		progress := ""
+		for {
+			_, err := fd.Read(buf)
+			if err != nil {
+				return
+			}
+			data += string(buf)
+			a := re.FindAllStringSubmatch(data, -1)
+			cp := ""
+			if len(a) > 0 && len(a[len(a)-1]) > 0 {
+				c, _ := strconv.Atoi(a[len(a)-1][len(a[len(a)-1])-1])
+				cp = fmt.Sprintf("%.2f", float64(c)/totalDuration/1000000)
+			}
+			if strings.Contains(data, "progress=end") {
+				cp = "done"
+			}
+			if cp == "" {
+				cp = ".0"
+			}
+			if cp != progress {
+				progress = cp
+				fmt.Println("progress: ", progress)
+			}
+		}
+	}()
+
+	return sockFileName
+}