FFmpegFrameRecorder close results in EXCEPTION_ACCESS_VIOLATION/SIGSEGV

[voomdoon]

Hi, I am trying to write simple video files (to be used for unit testing of other components reading that files).

example:

import java.awt.image.BufferedImage;

import org.bytedeco.javacv.FFmpegFrameRecorder;
import org.bytedeco.javacv.FrameRecorder.Exception;
import org.bytedeco.javacv.Java2DFrameConverter;

public class VideoGenerator {

	private static final int HEIGHT = 48;

	private static final int WIDTH = 64;

	public static void main(String[] args) throws Exception {
		new VideoGenerator().run(args[0]);
	}

	private static BufferedImage getImage(int i) {
		BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_ARGB);
		image.getGraphics().drawString(Integer.toString(i), 10, 10);
		return image;
	}

	private void run(String target) throws Exception {
		FFmpegFrameRecorder recorder = new FFmpegFrameRecorder(target, WIDTH, HEIGHT, 0);

		Java2DFrameConverter converter = new Java2DFrameConverter();

		recorder.start();

		for (int i = 0; i < 1000; i++) {
			recorder.record(converter.convert(getImage(i)));
		}

		System.out.println("flush...");
		recorder.flush();
		System.out.println("close...");
		recorder.close();
		System.out.println("done");
	}
}

the file gets written and is readable, but JVM crashes during close (done is not printed):

• EXCEPTION_ACCESS_VIOLATION on Windows 10 (avformat-58.dll+0xd9ae7)
• SIGSEGV on Ubuntu (libavformat.so.58+0x15a64c)

dependencies:

<dependency>
	<groupId>org.bytedeco</groupId>
	<artifactId>javacv</artifactId>
	<version>[1.5.5,1.6)</version>
</dependency>
<dependency>
	<groupId>org.bytedeco</groupId>
	<artifactId>javacv-platform</artifactId>
	<version>[1.5.5,1.6)</version>
</dependency>

[saudet]

I see what's going on. It's crashing in av_write_trailer() since that "frees the file private data", which means it can't be called twice. I've fixed that in commit e265c82, but we can still get this working correctly with JavaCV 1.5.5 by simply omitting the explicit call to flush(), which gets called in stop() anyway. Thanks for reporting!

[saudet]

Fix included in JavaCV 1.5.6. Enjoy!