use java multithread to pull the same one rtsp stream,some is correct some is error with "Could not open input"

javacv version:1.5.8; system:windows10 my code is `public void run() { LOG.info("####the {} rtsp stream:{},is running", count, rtspStream); System.setProperty("org.bytedeco.javacpp.logger", "slf4j"); System.setProperty("org.bytedeco.javacpp.logger.debug", "true"); FFmpegLogCallback.set(); try { grabber = new FFmpegFrameGrabber(rtspStream); grabber.setOption("rtsp_transport", "tcp"); grabber.setOption("stimeout", "2000000"); grabber.setFormat("rtsp");//rtsp FFmpegLogCallback.set(); grabber.start();

        int width = grabber.getImageWidth();
        int height = grabber.getImageHeight();
        if (width == 0 && height == 0) {
            LOG.error("[ERROR]   timeout...");
            return;
        }
        Frame frame = grabber.grabImage();
        while (null == frame) {
            LOG.info("device {} frame is null,execute restart grabber……", count);
            Thread.sleep(100);
            grabber.restart();
            frame = grabber.grabImage();
        }
        String file = fileUrl + File.separator + name;
        if (!FileUtil.exist(file)) {
            FileUtil.mkdir(file);
        }
        ImageIO.write(FrameToBufferedImage(frame), "jpg", new File(fileUrl + File.separator + name + File.separator + count + ".jpg"));
    } catch (FrameGrabber.Exception e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        if (null != grabber) {
            try {
                grabber.close();
                grabber.release();
            } catch (FrameGrabber.Exception e) {
                e.printStackTrace();
            }
        }
        countDownLatch.countDown();
    }

}

public static BufferedImage FrameToBufferedImage(Frame frame) {
    Java2DFrameConverter converter = new Java2DFrameConverter();
    BufferedImage bufferedImage = converter.getBufferedImage(frame);

// bufferedImage=rotateClockwise90(bufferedImage); return bufferedImage; }` the "rtspStream" is the same,I run with 2 thread is normal,More than 2 threads will report an error. Whether more than two rtsp streams can not be opened at the same time