如何从视频（mov）获取帧样本（jpeg）

Question

我想使用Java从视频文件（mov）中获取帧样本（jpeg）。是否有捷径可寻。当我在谷歌搜索时，我所能找到的就是从多个jpg中移动。我不知道也许找不到正确的关键字。

Answer 1

Xuggler完成工作。他们甚至给出了完全符合我需要的示例代码。链接在下面

http://xuggle.googlecode.com/svn/trunk/java/xuggle-
xuggler/src/com/xuggle/mediatool/demos/DecodeAndCaptureFrames.java

并且我修改了此链接中的代码，使其仅保存视频的第一帧。

import javax.imageio.ImageIO;

import java.io.File;

import java.awt.image.BufferedImage;

import com.xuggle.mediatool.IMediaReader;
import com.xuggle.mediatool.MediaListenerAdapter;
import com.xuggle.mediatool.ToolFactory;
import com.xuggle.mediatool.event.IVideoPictureEvent;
import com.xuggle.xuggler.Global;

/**
 *  * @author aclarke
 *    @author trebor
 */

public class DecodeAndCaptureFrames extends MediaListenerAdapter
{
  private int mVideoStreamIndex = -1;
  private boolean gotFirst = false;
  private String saveFile;
  private Exception e;
  /** Construct a DecodeAndCaptureFrames which reads and captures
   * frames from a video file.
   * 
   * @param filename the name of the media file to read
   */

  public DecodeAndCaptureFrames(String videoFile, String saveFile)throws Exception
  {
    // create a media reader for processing video
    this.saveFile = saveFile;
    this.e = null;
     IMediaReader reader = ToolFactory.makeReader(videoFile);

    // stipulate that we want BufferedImages created in BGR 24bit color space
    reader.setBufferedImageTypeToGenerate(BufferedImage.TYPE_3BYTE_BGR);


    // note that DecodeAndCaptureFrames is derived from
    // MediaReader.ListenerAdapter and thus may be added as a listener
    // to the MediaReader. DecodeAndCaptureFrames implements
    // onVideoPicture().

    reader.addListener(this);

    // read out the contents of the media file, note that nothing else
    // happens here.  action happens in the onVideoPicture() method
    // which is called when complete video pictures are extracted from
    // the media source

      while (reader.readPacket() == null && !gotFirst);

      if (e != null)
          throw e;
  }



  /** 
   * Called after a video frame has been decoded from a media stream.
   * Optionally a BufferedImage version of the frame may be passed
   * if the calling {@link IMediaReader} instance was configured to
   * create BufferedImages.
   * 
   * This method blocks, so return quickly.
   */

  public void onVideoPicture(IVideoPictureEvent event)
  {
    try
    {
      // if the stream index does not match the selected stream index,
      // then have a closer look

      if (event.getStreamIndex() != mVideoStreamIndex)
      {
        // if the selected video stream id is not yet set, go ahead an
        // select this lucky video stream

        if (-1 == mVideoStreamIndex)
          mVideoStreamIndex = event.getStreamIndex();

        // otherwise return, no need to show frames from this video stream

        else
          return;
      }

      ImageIO.write(event.getImage(), "jpg", new File(saveFile));
      gotFirst = true;

    }
    catch (Exception e)
    {
      this.e = e;
    }
  }
}