* Creates an image from a SeekableStream.
*/
public RenderedImage create(ParameterBlock paramBlock,
RenderingHints renderHints) {
ImagingListener listener = ImageUtil.getImagingListener(renderHints);
SeekableStream src = (SeekableStream)paramBlock.getObjectParameter(0);
try {
src.seek(0L);
} catch (IOException e) {
listener.errorOccurred(JaiI18N.getString("StreamRIF0"),
e, this, false);
// e.printStackTrace();
return null;
}
ImageDecodeParam param = null;
if (paramBlock.getNumParameters() > 1) {
param = (ImageDecodeParam)paramBlock.getObjectParameter(1);
}
String[] names = ImageCodec.getDecoderNames(src);
OperationRegistry registry =
JAI.getDefaultInstance().getOperationRegistry();
int bound = OpImage.OP_IO_BOUND;
ImageLayout layout = RIFUtil.getImageLayoutHint(renderHints);
if (renderHints != null) {
RenderingHints.Key key;
key = JAI.KEY_OPERATION_REGISTRY;
if (renderHints.containsKey(key)) {
registry = (OperationRegistry)renderHints.get(key);
}
key = JAI.KEY_OPERATION_BOUND;
if (renderHints.containsKey(key)) {
bound = ((Integer)renderHints.get(key)).intValue();
}
}
// Try to create a JAI operation with the given name
for (int i = 0; i < names.length; i++) {
RenderedImageFactory rif = null;
try {
rif = RIFRegistry.get(registry, names[i]);
} catch(IllegalArgumentException iae) {
// ignore IAE.
}
if(rif != null) {
RenderedImage im = RIFRegistry.create(registry, names[i],
paramBlock, renderHints);
if (im != null) {
return im;
}
}
}
// Set flag indicating that a recovery may be attempted if
// an OutOfMemoryError occurs during the decodeAsRenderedImage()
// call - which is only possible if the stream can seek backwards.
boolean canAttemptRecovery = src.canSeekBackwards();
// Save the stream position prior to decodeAsRenderedImage().
long streamPosition = Long.MIN_VALUE;
if(canAttemptRecovery) {
try {
streamPosition = src.getFilePointer();
} catch(IOException ioe) {
listener.errorOccurred(JaiI18N.getString("StreamRIF1"),
ioe, this, false);
// Unset the recovery attempt flag but otherwise
// ignore the exception.
canAttemptRecovery = false;
}
}
// Try to create an ImageDecoder directly
for (int i = 0; i < names.length; i++) {
ImageDecoder dec =
ImageCodec.createImageDecoder(names[i], src, param);
RenderedImage im = null;
try {
im = dec.decodeAsRenderedImage();
} catch(OutOfMemoryError memoryError) {
// Ran out of memory - may be due to the decoder being
// obliged to read the entire image when it creates the
// RenderedImage it returns.
if(canAttemptRecovery) {
// First flush the cache if one is defined.
TileCache cache = RIFUtil.getTileCacheHint(renderHints);
if(cache != null) {
cache.flush();
}
// Force garbage collection.
System.gc(); //slow
try {
// Reposition the stream before the previous decoding.
src.seek(streamPosition);
// Retry image decoding.
im = dec.decodeAsRenderedImage();
} catch (IOException ioe) {
listener.errorOccurred(JaiI18N.getString("StreamRIF2"),