import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.util.Base64;
import javax.imageio.ImageIO;

public class PngPLTEChunkMissingTest {

    // PNG image test case (encoded as base64)
    private static String inputImageBase64 = "iVBORw0KGgoAAAANSUhEUgAAAAEAAAAB"
            + "CAMAAAA6fptVAAAACklEQVQYV2P4DwABAQEAWk1v8QAAAABJRU5ErkJgggo=";

    public static void main(String[] args) throws java.io.IOException {
        // Convert test case into input stream
        byte[] inputBytes = Base64.getDecoder().decode(inputImageBase64);
        InputStream in = new ByteArrayInputStream(inputBytes);

        // Attempt to read PNG
        ImageIO.read(in); // Throws java.lang.NullPointerException!
    }
}