diff --git a/core/uploader.go b/core/uploader.go
index 77db5e1..c31e7d1 100644
--- a/core/uploader.go
+++ b/core/uploader.go
@@ -238,13 +238,13 @@ func extractThumb(outputURI *url.URL, segmentFileName string, storageFallbackURL
 		return fmt.Errorf("temp file creation failed: %w", err)
 	}
 	defer os.RemoveAll(tmpDir)
-	outFile := filepath.Join(tmpDir, "out.jpg")
+	outFile := filepath.Join(tmpDir, "out.png")
 
 	args := []string{
 		"-i", segmentFileName,
 		"-ss", "00:00:00",
 		"-vframes", "1",
-		"-vf", "scale=854:480:force_original_aspect_ratio=decrease",
+		"-vf", "scale=640:360:force_original_aspect_ratio=decrease",
 		"-y",
 		outFile,
 	}
@@ -264,7 +264,7 @@ func extractThumb(outputURI *url.URL, segmentFileName string, storageFallbackURL
 	}
 
 	// two thumbs, one at session level, the other at stream level
-	thumbURLs := []*url.URL{outputURI.JoinPath("../latest.jpg"), outputURI.JoinPath("../../../latest.jpg")}
+	thumbURLs := []*url.URL{outputURI.JoinPath("../latest.png"), outputURI.JoinPath("../../../latest.png")}
 	fields := &drivers.FileProperties{CacheControl: "max-age=5"}
 	errGroup := &errgroup.Group{}