services

services/tiktak/video/preview.go

@@ -0,0 +1,62 @@
+package video
+
+import (
+	"context"
+	"fmt"
+	"github.com/disintegration/imaging"
+	"image"
+	"image/png"
+	"os"
+	"os/exec"
+	"strings"
+	"time"
+)
+
+var (
+	ProcessingDeadline = 2 * time.Second
+	semaphore          = make(chan struct{}, 75)
+)
+
+func generatePreview(ctx context.Context, inp string, out string) error {
+	cmd := exec.CommandContext(ctx, "ffmpeg", "-y", "-i", inp, "-vframes", "1", out)
+	s := strings.Builder{}
+	cmd.Stdout = &s
+	cmd.Stderr = &s
+	err := cmd.Run()
+	if err != nil {
+		fmt.Println(s.String())
+	}
+	return err
+}
+
+func GeneratePreview(ctx context.Context, inp string, out string) error {
+	select {
+	case semaphore <- struct{}{}:
+		ctx, cancel := context.WithTimeout(ctx, ProcessingDeadline)
+		defer func() {
+			cancel()
+			<-semaphore
+		}()
+		return generatePreview(ctx, inp, out)
+	case <-ctx.Done():
+		return ctx.Err()
+	}
+}
+
+func Blur(inp string, out string) error {
+	f, err := os.Open(inp)
+	if err != nil {
+		return err
+	}
+	img, _, err := image.Decode(f)
+	if err != nil {
+		return err
+	}
+	outimg := imaging.Blur(img, 5)
+	outfile, err := os.Create(out)
+	if err != nil {
+		return err
+	}
+	defer outfile.Close()
+	return png.Encode(outfile, outimg)
+}