implement libav in some methods

util/av/thumbnail.go

@@ -1,24 +1,115 @@
 package av
 
 import (
-	ffmpeg "github.com/u2takey/ffmpeg-go"
+	"errors"
+	"fmt"
+	"image/jpeg"
+	"os"
+	"time"
+
+	"github.com/asticode/go-astiav"
 )
 
-func ExtractVideoThumbnail(
-	videoPath string,
-	thumbnailPath string,
-) error {
-	err := ffmpeg.
-		Input(videoPath).
-		Output(thumbnailPath, ffmpeg.KwArgs{
-			"vframes": 1,
-			"ss":      "00:00:01",
-		}).
-		Silent(true).
-		OverWriteOutput().
-		Run()
+func ExtractVideoThumbnail(videoPath string, imagePath string) error {
+	formatCtx := astiav.AllocFormatContext()
+	defer formatCtx.Free()
+
+	err := formatCtx.OpenInput(videoPath, nil, nil)
 	if err != nil {
-		return err
+		return fmt.Errorf("failed opening input: %w", err)
 	}
-	return nil
+
+	err = formatCtx.FindStreamInfo(nil)
+	if err != nil {
+		return fmt.Errorf("failed finding stream info: %w", err)
+	}
+
+	stream, codec, err := formatCtx.FindBestStream(
+		astiav.MediaTypeVideo, -1, -1)
+	if err != nil {
+		return fmt.Errorf("failed finding best video stream: %w", err)
+	}
+
+	codecParameters := stream.CodecParameters()
+
+	decoder := astiav.FindDecoder(codec.ID())
+	if decoder == nil {
+		return fmt.Errorf("no decoder found for codec %s", codec.String())
+	}
+
+	codecCtx := astiav.AllocCodecContext(decoder)
+	defer codecCtx.Free()
+
+	err = codecParameters.ToCodecContext(codecCtx)
+	if err != nil {
+		return fmt.Errorf("failed setting codec parameters: %w", err)
+	}
+
+	err = codecCtx.Open(decoder, nil)
+	if err != nil {
+		return fmt.Errorf("failed opening codec: %w", err)
+	}
+
+	packet := astiav.AllocPacket()
+	defer packet.Free()
+	frame := astiav.AllocFrame()
+	defer frame.Free()
+
+	startTime := time.Now()
+	timeout := 5 * time.Second
+
+	// read frames until we find a video frame or timeout
+	for time.Since(startTime) < timeout {
+		err := formatCtx.ReadFrame(packet)
+		if err != nil {
+			if errors.Is(err, astiav.ErrEof) {
+				return fmt.Errorf("end of file reached before finding video frame")
+			}
+			return fmt.Errorf("failed reading frame: %w", err)
+		}
+
+		if packet.StreamIndex() != stream.Index() {
+			packet.Unref()
+			continue
+		}
+
+		err = codecCtx.SendPacket(packet)
+		if err != nil {
+			return fmt.Errorf("failed sending packet to decoder: %w", err)
+		}
+
+		err = codecCtx.ReceiveFrame(frame)
+		if err != nil {
+			if errors.Is(err, astiav.ErrEagain) || errors.Is(err, astiav.ErrEof) {
+				packet.Unref()
+				continue
+			}
+			return fmt.Errorf("failed receiving frame from decoder: %w", err)
+		}
+
+		img, err := frame.Data().GuessImageFormat()
+		if err != nil {
+			return fmt.Errorf("failed guessing image format: %w", err)
+		}
+		err = frame.Data().ToImage(img)
+		if err != nil {
+			return fmt.Errorf("failed converting frame to image: %w", err)
+		}
+		packet.Unref()
+
+		file, err := os.Create(imagePath)
+		if err != nil {
+			return fmt.Errorf("failed creating image file: %w", err)
+		}
+		defer file.Close()
+
+		err = jpeg.Encode(file, img, nil)
+		if err != nil {
+			return fmt.Errorf("failed encoding image: %w", err)
+		}
+
+		return nil
+	}
+
+	return fmt.Errorf("timeout while waiting for video frame")
 }