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javaxuggler

Error with java video decoding by Xuggler


I am learning Xuggler(a library supports video streaming for Java) by following the code in a tutorial teaching how to decode and play video.

I supposed this snippet of code is reliable, but when I want to play the video read on my window, I got the error telling me

Exception in thread "main" java.lang.RuntimeException: got error decoding video in: C:/Users/swnmlab/1.mp4

This error happens when this line got executed

int bytesDecoded = videoCoder.decodeVideo(picture, packet,offset);

I used debugger to step into and find that xuggle-xuggler.jar has no source attachment, does anyone has encountered this problem before?

import java.awt.image.BufferedImage;

import com.xuggle.xuggler.ICodec.Type;
import com.xuggle.xuggler.IContainer;
import com.xuggle.xuggler.IPacket;
import com.xuggle.xuggler.IPixelFormat;
import com.xuggle.xuggler.IStream;
import com.xuggle.xuggler.IStreamCoder;
import com.xuggle.xuggler.IVideoPicture;
import com.xuggle.xuggler.IVideoResampler;
import com.xuggle.xuggler.Utils;
import com.xuggle.xuggler.demos.VideoImage;

public class DecodeAndPlayVideo {
    public static void main(String[] args) {
        String filename = "C:/Users/swnmlab/1.mp4";

        // Create a Xuggler container object
        IContainer container = IContainer.make();

        // Open up the container
        if (container.open(filename, IContainer.Type.READ, null) < 0)
            throw new IllegalArgumentException("could not open file: "
                    + filename);

        // query how many streams the call to open found
        int numStreams = container.getNumStreams();

        // and iterate through the streams to find the first video stream
        int videoStreamId = -1;
        IStreamCoder videoCoder = null;
        for (int i = 0; i < numStreams; i++) {
            // Find the stream object
            IStream stream = container.getStream(i);
            // Get the pre-configured decoder that can decode this stream;
            IStreamCoder coder = stream.getStreamCoder();

            if (coder.getCodecType() == Type.CODEC_TYPE_VIDEO) {
                videoStreamId = i;
                videoCoder = coder;
                break;
            }
        }
        if (videoStreamId == -1)
            throw new RuntimeException(
                    "could not find video stream in container: " + filename);

        if (videoCoder.acquire() < 0)
            throw new RuntimeException(
                    "could not open video decoder for container: " + filename);

        IVideoResampler resampler = null;
        if (videoCoder.getPixelType() != IPixelFormat.Type.BGR24) {
            // if this stream is not in BGR24, we're going to need to
            // convert it. The VideoResampler does that for us.
            resampler = IVideoResampler.make(videoCoder.getWidth(),
                    videoCoder.getHeight(), IPixelFormat.Type.BGR24,
                    videoCoder.getWidth(), videoCoder.getHeight(),
                    videoCoder.getPixelType());
            if (resampler == null)
                throw new RuntimeException("could not create color space "
                        + "resampler for: " + filename);
        }

        /*
         * And once we have that, we draw a window on screen
         */
        openJavaWindow();

        IPacket packet = IPacket.make();
        while (container.readNextPacket(packet) >= 0) {
            /*
             * Now we have a packet, let's see if it belongs to our video stream
             */
            if (packet.getStreamIndex() == videoStreamId) {
                IVideoPicture picture = IVideoPicture.make(
                        videoCoder.getPixelType(), videoCoder.getWidth(),
                        videoCoder.getHeight());

                int offset = 0;
                while (offset < packet.getSize()) {
                    /*
                     * Now, we decode the video, checking for any errors.
                     */
                    int bytesDecoded = videoCoder.decodeVideo(picture, packet,
                            offset);
                    if (bytesDecoded < 0)
                        throw new RuntimeException(
                                "got error decoding video in: " + filename);
                    offset += bytesDecoded;

                    /*
                     * Some decoders will consume data in a packet, but will not
                     * be able to construct a full video picture yet. Therefore
                     * you should always check if you got a complete picture
                     * from the decoder
                     */
                    if (picture.isComplete()) {
                        IVideoPicture newPic = picture;
                        /*
                         * If the resampler is not null, that means we didn't
                         * get the video in BGR24 format and need to convert it
                         * into BGR24 format.
                         */
                        if (resampler != null) {
                            // we must resample
                            newPic = IVideoPicture.make(
                                    resampler.getOutputPixelFormat(),
                                    picture.getWidth(), picture.getHeight());
                            if (resampler.resample(newPic, picture) < 0)
                                throw new RuntimeException(
                                        "could not resample video from: "
                                                + filename);
                        }
                        if (newPic.getPixelType() != IPixelFormat.Type.BGR24)
                            throw new RuntimeException("could not decode video"
                                    + " as BGR 24 bit data in: " + filename);


                        @SuppressWarnings("deprecation")
                        BufferedImage javaImage = Utils.videoPictureToImage(newPic);

                        // and display it on the Java Swing window
                        updateJavaWindow(javaImage);    
                    }

                }
            } else {
                /*
                 * This packet isn't part of our video stream, so we just silently drop it.
                 */
                do {
                } while (false);
            }
        }

        closeJavaWindow();

    }

    private static VideoImage mScreen = null;
    private static void updateJavaWindow(BufferedImage javaImage) {
        mScreen.setImage(javaImage);
    }

    private static void openJavaWindow() {
        mScreen = new VideoImage();
    }

    private static void closeJavaWindow() {
        System.exit(0);
    }
}

P.S. If you want to try this library, you can find the installing file here, and then follow the steps on this page finish installing this library on Windows.


I found the error happened because I cahnged the original code

        if (videoCoder.open() < 0)
            throw new RuntimeException(
                    "could not open video decoder for container: " + filename);

to

        if (videoCoder.acquire() < 0)
            throw new RuntimeException(
                    "could not open video decoder for container: " + filename);

since open() method causes deprecation warning, so I used auto complete to find a method that looks like open(), then changed to acquire(). I thought that was OK since no "could not open video decoder for container: " exception thrown out.So just follow the sample code.


Solution

  • I went through your code and found that you obtained a videoCoder, but you didn't open it before playing. Maybe that is why you couldn't decode it. So could you please have a try?

    if (videoCoder.open() < 0)
        throw new RuntimeException(
                "could not open video decoder for container: "
                        + filename);
    IVideoResampler resampler = null;