pixelgrabber.java

《移动Agent技术》一书的所有章节源代码。

     * If no width was specified for the rectangle of pixels to grab then
     * then this information will only be available after the image has
     * delivered the dimensions.
     * @return the final height used for the pixel buffer or -1 if the height
     * is not yet known
     * @see #getStatus
     */
    public synchronized int getHeight() {
	return (dstH < 0) ? -1 : dstH;
    }

    /**
     * Get the pixel buffer.  If the PixelGrabber was not constructed
     * with an explicit pixel buffer to hold the pixels then this method
     * will return null until the size and format of the image data is
     * known.
     * Since the PixelGrabber may fall back on accumulating the data
     * in the default RGB ColorModel at any time if the source image
     * uses more than one ColorModel to deliver the data, the array
     * object returned by this method may change over time until the
     * image grab is complete.
     * @return either a byte array or an int array
     * @see #getStatus
     */
    public synchronized Object getPixels() {
	return (bytePixels == null)
	    ? ((Object) intPixels)
	    : ((Object) bytePixels);
    }

    /**
     * Get the ColorModel for the pixels stored in the array.  If the
     * PixelGrabber was constructed with an explicit pixel buffer then
     * this method will always return the default RGB ColorModel,
     * otherwise it may return null until the ColorModel used by the
     * ImageProducer is known.
     * Since the PixelGrabber may fall back on accumulating the data
     * in the default RGB ColorModel at any time if the source image
     * uses more than one ColorModel to deliver the data, the ColorModel
     * object returned by this method may change over time until the
     * image grab is complete.
     * @return the ColorModel object used for storing the pixels
     * @see #getStatus
     * @see ColorModel#getRGBdefault
     */
    public synchronized ColorModel getColorModel() {
	return imageModel;
    }

    /**
     * The setDimensions method is part of the ImageConsumer API which
     * this class must implement to retrieve the pixels.
     */
    public void setDimensions(int width, int height) {
	if (dstW < 0) {
	    dstW = width - dstX;
	}
	if (dstH < 0) {
	    dstH = height - dstY;
	}
	if (dstW <= 0 || dstH <= 0) {
	    imageComplete(STATICIMAGEDONE);
	} else if (intPixels == null &&
		   imageModel == ColorModel.getRGBdefault()) {
	    intPixels = new int[dstW * dstH];
	    dstScan = dstW;
	    dstOff = 0;
	}
	flags |= (ImageObserver.WIDTH | ImageObserver.HEIGHT);
    }

    /**
     * The setHints method is part of the ImageConsumer API which
     * this class must implement to retrieve the pixels.
     */
    public void setHints(int hints) {
	return;
    }

    /**
     * The setProperties method is part of the ImageConsumer API which
     * this class must implement to retrieve the pixels.
     */
    public void setProperties(Hashtable props) {
	return;
    }

    /**
     * The setColorModel method is part of the ImageConsumer API which
     * this class must implement to retrieve the pixels.
     */
    public void setColorModel(ColorModel model) {
	return;
    }

    private void convertToRGB() {
	int size = dstW * dstH;
	int newpixels[] = new int[size];
	if (bytePixels != null) {
	    for (int i = 0; i < size; i++) {
		newpixels[i] = imageModel.getRGB(bytePixels[i] & 0xff);
	    }
	} else if (intPixels != null) {
	    for (int i = 0; i < size; i++) {
		newpixels[i] = imageModel.getRGB(intPixels[i]);
	    }
	}
	bytePixels = null;
	intPixels = newpixels;
	dstScan = dstW;
	dstOff = 0;
	imageModel = ColorModel.getRGBdefault();
    }

    /**
     * The setPixels method is part of the ImageConsumer API which
     * this class must implement to retrieve the pixels.
     */
    public void setPixels(int srcX, int srcY, int srcW, int srcH,
			  ColorModel model,
			  byte pixels[], int srcOff, int srcScan) {
	if (srcY < dstY) {
	    int diff = dstY - srcY;
	    if (diff >= srcH) {
		return;
	    }
	    srcOff += srcScan * diff;
	    srcY += diff;
	    srcH -= diff;
	}
	if (srcY + srcH > dstY + dstH) {
	    srcH = (dstY + dstH) - srcY;
	    if (srcH <= 0) {
		return;
	    }
	}
	if (srcX < dstX) {
	    int diff = dstX - srcX;
	    if (diff >= srcW) {
		return;
	    }
	    srcOff += diff;
	    srcX += diff;
	    srcW -= diff;
	}
	if (srcX + srcW > dstX + dstW) {
	    srcW = (dstX + dstW) - srcX;
	    if (srcW <= 0) {
		return;
	    }
	}
	int dstPtr = dstOff + (srcY - dstY) * dstScan + (srcX - dstX);
	if (intPixels == null) {
	    if (bytePixels == null) {
		bytePixels = new byte[dstW * dstH];
		dstScan = dstW;
		dstOff = 0;
		imageModel = model;
	    } else if (imageModel != model) {
		convertToRGB();
	    }
	    if (bytePixels != null) {
		for (int h = srcH; h > 0; h--) {
		    System.arraycopy(pixels, srcOff, bytePixels, dstPtr, srcW);
		    srcOff += srcScan;
		    dstPtr += dstScan;
		}
	    }
	}
	if (intPixels != null) {
	    int dstRem = dstScan - srcW;
	    int srcRem = srcScan - srcW;
	    for (int h = srcH; h > 0; h--) {
		for (int w = srcW; w > 0; w--) {
		    intPixels[dstPtr++] = model.getRGB(pixels[srcOff++]&0xff);
		}
		srcOff += srcRem;
		dstPtr += dstRem;
	    }
	}
	flags |= ImageObserver.SOMEBITS;
    }

    /**
     * The setPixels method is part of the ImageConsumer API which
     * this class must implement to retrieve the pixels.
     */
    public void setPixels(int srcX, int srcY, int srcW, int srcH,
			  ColorModel model,
			  int pixels[], int srcOff, int srcScan) {
	if (srcY < dstY) {
	    int diff = dstY - srcY;
	    if (diff >= srcH) {
		return;
	    }
	    srcOff += srcScan * diff;
	    srcY += diff;
	    srcH -= diff;
	}
	if (srcY + srcH > dstY + dstH) {
	    srcH = (dstY + dstH) - srcY;
	    if (srcH <= 0) {
		return;
	    }
	}
	if (srcX < dstX) {
	    int diff = dstX - srcX;
	    if (diff >= srcW) {
		return;
	    }
	    srcOff += diff;
	    srcX += diff;
	    srcW -= diff;
	}
	if (srcX + srcW > dstX + dstW) {
	    srcW = (dstX + dstW) - srcX;
	    if (srcW <= 0) {
		return;
	    }
	}
	if (intPixels == null) {
	    if (bytePixels == null) {
		intPixels = new int[dstW * dstH];
		dstScan = dstW;
		dstOff = 0;
		imageModel = model;
	    } else {
		convertToRGB();
	    }
	}
	int dstPtr = dstOff + (srcY - dstY) * dstScan + (srcX - dstX);
	if (imageModel == model) {
	    for (int h = srcH; h > 0; h--) {
		System.arraycopy(pixels, srcOff, intPixels, dstPtr, srcW);
		srcOff += srcScan;
		dstPtr += dstScan;
	    }
	} else {
	    if (imageModel != ColorModel.getRGBdefault()) {
		convertToRGB();
	    }
	    int dstRem = dstScan - srcW;
	    int srcRem = srcScan - srcW;
	    for (int h = srcH; h > 0; h--) {
		for (int w = srcW; w > 0; w--) {
		    intPixels[dstPtr++] = model.getRGB(pixels[srcOff++]);
		}
		srcOff += srcRem;
		dstPtr += dstRem;
	    }
	}
	flags |= ImageObserver.SOMEBITS;
    }

    /**
     * The imageComplete method is part of the ImageConsumer API which
     * this class must implement to retrieve the pixels.
     */
    public synchronized void imageComplete(int status) {
	grabbing = false;
	switch (status) {
	default:
	case IMAGEERROR:
	    flags |= ImageObserver.ERROR | ImageObserver.ABORT;
	    break;
	case IMAGEABORTED:
	    flags |= ImageObserver.ABORT;
	    break;
	case STATICIMAGEDONE:
	    flags |= ImageObserver.ALLBITS;
	    break;
	case SINGLEFRAMEDONE:
	    flags |= ImageObserver.FRAMEBITS;
	    break;
	}
	producer.removeConsumer(this);
	notifyAll();
    }

    /**
     * DEPRECATED:  Replaced by getStatus().
     */
    public synchronized int status() {
	return flags;
    }
}