public class PixelGrabber extends Object implements ImageConsumer
The PixelGrabber class implements an ImageConsumer which can be attached to an Image or ImageProducer object to retrieve a subset of the pixels in that image. Here is an example:
public void handlesinglepixel(int x, int y, int pixel) {
int alpha = (pixel >> 24) & 0xff;
int red = (pixel >> 16) & 0xff;
int green = (pixel >> 8) & 0xff;
int blue = (pixel ) & 0xff;
// Deal with the pixel as necessary...
}
public void handlepixels(Image img, int x, int y, int w, int h) {
int[] pixels = new int[w * h];
PixelGrabber pg = new PixelGrabber(img, x, y, w, h, pixels, 0, w);
try {
pg.grabPixels();
} catch (InterruptedException e) {
System.err.println("interrupted waiting for pixels!");
return;
}
if ((pg.getStatus() & ImageObserver.ABORT) != 0) {
System.err.println("image fetch aborted or errored");
return;
}
for (int j = 0; j < h; j++) {
for (int i = 0; i < w; i++) {
handlesinglepixel(x+i, y+j, pixels[j * w + i]);
}
}
} ColorModel.getRGBdefault()COMPLETESCANLINES, IMAGEABORTED, IMAGEERROR, RANDOMPIXELORDER, SINGLEFRAME, SINGLEFRAMEDONE, SINGLEPASS, STATICIMAGEDONE, TOPDOWNLEFTRIGHT public PixelGrabber(Image img,
int x,
int y,
int w,
int h,
int[] pix,
int off,
int scansize) Create a PixelGrabber object to grab the (x, y, w, h) rectangular section of pixels from the specified image into the given array. The pixels are stored into the array in the default RGB ColorModel. The RGB data for pixel (i, j) where (i, j) is inside the rectangle (x, y, w, h) is stored in the array at pix[(j - y) * scansize + (i - x) + off].
img - the image to retrieve pixels fromx - the x coordinate of the upper left corner of the rectangle of pixels to retrieve from the image, relative to the default (unscaled) size of the imagey - the y coordinate of the upper left corner of the rectangle of pixels to retrieve from the imagew - the width of the rectangle of pixels to retrieveh - the height of the rectangle of pixels to retrievepix - the array of integers which are to be used to hold the RGB pixels retrieved from the imageoff - the offset into the array of where to store the first pixelscansize - the distance from one row of pixels to the next in the arrayColorModel.getRGBdefault()public PixelGrabber(ImageProducer ip,
int x,
int y,
int w,
int h,
int[] pix,
int off,
int scansize) Create a PixelGrabber object to grab the (x, y, w, h) rectangular section of pixels from the image produced by the specified ImageProducer into the given array. The pixels are stored into the array in the default RGB ColorModel. The RGB data for pixel (i, j) where (i, j) is inside the rectangle (x, y, w, h) is stored in the array at pix[(j - y) * scansize + (i - x) + off].
ip - the ImageProducer that produces the image from which to retrieve pixelsx - the x coordinate of the upper left corner of the rectangle of pixels to retrieve from the image, relative to the default (unscaled) size of the imagey - the y coordinate of the upper left corner of the rectangle of pixels to retrieve from the imagew - the width of the rectangle of pixels to retrieveh - the height of the rectangle of pixels to retrievepix - the array of integers which are to be used to hold the RGB pixels retrieved from the imageoff - the offset into the array of where to store the first pixelscansize - the distance from one row of pixels to the next in the arrayColorModel.getRGBdefault()public PixelGrabber(Image img,
int x,
int y,
int w,
int h,
boolean forceRGB) Create a PixelGrabber object to grab the (x, y, w, h) rectangular section of pixels from the specified image. The pixels are accumulated in the original ColorModel if the same ColorModel is used for every call to setPixels, otherwise the pixels are accumulated in the default RGB ColorModel. If the forceRGB parameter is true, then the pixels will be accumulated in the default RGB ColorModel anyway. A buffer is allocated by the PixelGrabber to hold the pixels in either case. If (w < 0) or (h < 0), then they will default to the remaining width and height of the source data when that information is delivered.
img - the image to retrieve the image data fromx - the x coordinate of the upper left corner of the rectangle of pixels to retrieve from the image, relative to the default (unscaled) size of the imagey - the y coordinate of the upper left corner of the rectangle of pixels to retrieve from the imagew - the width of the rectangle of pixels to retrieveh - the height of the rectangle of pixels to retrieveforceRGB - true if the pixels should always be converted to the default RGB ColorModelpublic void startGrabbing()
Request the PixelGrabber to start fetching the pixels.
public void abortGrabbing()
Request the PixelGrabber to abort the image fetch.
public boolean grabPixels()
throws InterruptedException Request the Image or ImageProducer to start delivering pixels and wait for all of the pixels in the rectangle of interest to be delivered.
InterruptedException - Another thread has interrupted this thread.public boolean grabPixels(long ms)
throws InterruptedException Request the Image or ImageProducer to start delivering pixels and wait for all of the pixels in the rectangle of interest to be delivered or until the specified timeout has elapsed. This method behaves in the following ways, depending on the value of ms:
ms == 0, waits until all pixels are delivered ms > 0, waits until all pixels are delivered as timeout expires. ms < 0, returns true if all pixels are grabbed, false otherwise and does not wait. ms - the number of milliseconds to wait for the image pixels to arrive before timing outInterruptedException - Another thread has interrupted this thread.public int getStatus()
Return the status of the pixels. The ImageObserver flags representing the available pixel information are returned.
ImageObserverpublic int getWidth()
Get the width of the pixel buffer (after adjusting for image width). 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.
getStatus()public int getHeight()
Get the height of the pixel buffer (after adjusting for image height). 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.
getStatus()public Object getPixels()
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.
getStatus(), setPixels(int, int, int, int, ColorModel, byte[], int, int), setPixels(int, int, int, int, ColorModel, int[], int, int)
public ColorModel getColorModel()
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 and may not reflect any of the ColorModel objects that was used by the ImageProducer to deliver the pixels.
getStatus(), ColorModel.getRGBdefault(), setColorModel(ColorModel)
public void setDimensions(int width,
int height) The setDimensions method is part of the ImageConsumer API which this class must implement to retrieve the pixels.
Note: This method is intended to be called by the ImageProducer of the Image whose pixels are being grabbed. Developers using this class to retrieve pixels from an image should avoid calling this method directly since that operation could result in problems with retrieving the requested pixels.
setDimensions in interface ImageConsumer
width - the width of the dimensionheight - the height of the dimensionpublic void setHints(int hints)
The setHints method is part of the ImageConsumer API which this class must implement to retrieve the pixels.
Note: This method is intended to be called by the ImageProducer of the Image whose pixels are being grabbed. Developers using this class to retrieve pixels from an image should avoid calling this method directly since that operation could result in problems with retrieving the requested pixels.
setHints in interface ImageConsumer
hints - a set of hints used to process the pixelspublic void setProperties(Hashtable<?,?> props)
The setProperties method is part of the ImageConsumer API which this class must implement to retrieve the pixels.
Note: This method is intended to be called by the ImageProducer of the Image whose pixels are being grabbed. Developers using this class to retrieve pixels from an image should avoid calling this method directly since that operation could result in problems with retrieving the requested pixels.
setProperties in interface ImageConsumer
props - the list of propertiespublic void setColorModel(ColorModel model)
The setColorModel method is part of the ImageConsumer API which this class must implement to retrieve the pixels.
Note: This method is intended to be called by the ImageProducer of the Image whose pixels are being grabbed. Developers using this class to retrieve pixels from an image should avoid calling this method directly since that operation could result in problems with retrieving the requested pixels.
setColorModel in interface ImageConsumer
model - the specified ColorModel
getColorModel()public void setPixels(int srcX,
int srcY,
int srcW,
int srcH,
ColorModel model,
byte[] pixels,
int srcOff,
int srcScan) The setPixels method is part of the ImageConsumer API which this class must implement to retrieve the pixels.
Note: This method is intended to be called by the ImageProducer of the Image whose pixels are being grabbed. Developers using this class to retrieve pixels from an image should avoid calling this method directly since that operation could result in problems with retrieving the requested pixels.
setPixels in interface ImageConsumer
srcX - the X coordinate of the upper-left corner of the area of pixels to be setsrcY - the Y coordinate of the upper-left corner of the area of pixels to be setsrcW - the width of the area of pixelssrcH - the height of the area of pixelsmodel - the specified ColorModel
pixels - the array of pixelssrcOff - the offset into the pixels arraysrcScan - the distance from one row of pixels to the next in the pixels arraygetPixels()public void setPixels(int srcX,
int srcY,
int srcW,
int srcH,
ColorModel model,
int[] pixels,
int srcOff,
int srcScan) The setPixels method is part of the ImageConsumer API which this class must implement to retrieve the pixels.
Note: This method is intended to be called by the ImageProducer of the Image whose pixels are being grabbed. Developers using this class to retrieve pixels from an image should avoid calling this method directly since that operation could result in problems with retrieving the requested pixels.
setPixels in interface ImageConsumer
srcX - the X coordinate of the upper-left corner of the area of pixels to be setsrcY - the Y coordinate of the upper-left corner of the area of pixels to be setsrcW - the width of the area of pixelssrcH - the height of the area of pixelsmodel - the specified ColorModel
pixels - the array of pixelssrcOff - the offset into the pixels arraysrcScan - the distance from one row of pixels to the next in the pixels arraygetPixels()public void imageComplete(int status)
The imageComplete method is part of the ImageConsumer API which this class must implement to retrieve the pixels.
Note: This method is intended to be called by the ImageProducer of the Image whose pixels are being grabbed. Developers using this class to retrieve pixels from an image should avoid calling this method directly since that operation could result in problems with retrieving the requested pixels.
imageComplete in interface ImageConsumer
status - the status of image loadingImageProducer.removeConsumer(java.awt.image.ImageConsumer)public int status()
Returns the status of the pixels. The ImageObserver flags representing the available pixel information are returned. This method and getStatus have the same implementation, but getStatus is the preferred method because it conforms to the convention of naming information-retrieval methods with the form "getXXX".
ImageObserver, getStatus()
© 1993–2017, Oracle and/or its affiliates. All rights reserved.
Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
Various third party code in OpenJDK is licensed under different licenses (see Debian package).
Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.