import javax.media.Codec; //导入依赖的package包/类
/**
    * Setting the encoding quality to the specified value on the JPEG encoder.
    * 0.5 is a good default.
    */
   void setJPEGQuality(Player p, float val) {

Control cs[] = p.getControls();
QualityControl qc = null;
VideoFormat jpegFmt = new VideoFormat(VideoFormat.JPEG);

// Loop through the controls to find the Quality control for
	// the JPEG encoder.
for (int i = 0; i < cs.length; i++) {

    if (cs[i] instanceof QualityControl &&
	cs[i] instanceof Owned) {
	Object owner = ((Owned)cs[i]).getOwner();

	// Check to see if the owner is a Codec.
	// Then check for the output format.
	if (owner instanceof Codec) {
	    Format fmts[] = ((Codec)owner).getSupportedOutputFormats(null);
	    for (int j = 0; j < fmts.length; j++) {
		if (fmts[j].matches(jpegFmt)) {
		    qc = (QualityControl)cs[i];
    		    qc.setQuality(val);
		    System.err.println("- Setting quality to " + 
				val + " on " + qc);
		    break;
		}
	    }
	}
	if (qc != null)
	    break;
    }
}
   }