我有一个 18000 * 18000 尺寸和1.20 GB大小的 tiff 文件。tiff 有 72 DPI。
我想使用 400 DPI 将此 TIFF 转换为 PNG/JPEG。
我正在使用以下代码来做到这一点
public static void ConvertTiffToJpg(String str_TiffUrl,
String str_JpgFileDestinationUrl) throws Exception {
try {
FileSeekableStream obj_FileSeekableStream = new FileSeekableStream(
new File(str_TiffUrl));
ImageDecoder obj_ImageDecoder = ImageCodec.createImageDecoder(
"tiff", obj_FileSeekableStream, null);
RenderedImage obj_RenderedImage = obj_ImageDecoder
.decodeAsRenderedImage();
JAI.create("filestore", obj_RenderedImage,
str_JpgFileDestinationUrl, "jpeg");
obj_RenderedImage = null;
obj_ImageDecoder = null;
obj_FileSeekableStream.close();
} catch (Exception ex) {
throw ex;
}
上面的代码非常适用于较小的图像，然后指定的图像，例如尺寸小于 5000 * 5000 的 tiff 图像可以轻松转换为 JPEG / PNG [虽然我需要更改 PNG 编码器]，
但是当我尝试为上述文件运行相同的代码时，它会引发以下异常
Error: One factory fails for the operation "encode"
Occurs in: javax.media.jai.ThreadSafeOperationRegistry
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at javax.media.jai.FactoryCache.invoke(FactoryCache.java:122)
at javax.media.jai.OperationRegistry.invokeFactory(OperationRegistry.java:1674)
at javax.media.jai.ThreadSafeOperationRegistry.invokeFactory(ThreadSafeOperationRegistry.java:473)
at javax.media.jai.registry.RIFRegistry.create(RIFRegistry.java:332)
at com.sun.media.jai.opimage.FileStoreRIF.create(FileStoreRIF.java:138)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at javax.media.jai.FactoryCache.invoke(FactoryCache.java:122)
at javax.media.jai.OperationRegistry.invokeFactory(OperationRegistry.java:1674)
at javax.media.jai.ThreadSafeOperationRegistry.invokeFactory(ThreadSafeOperationRegistry.java:473)
at javax.media.jai.registry.RIFRegistry.create(RIFRegistry.java:332)
at javax.media.jai.RenderedOp.createInstance(RenderedOp.java:819)
at javax.media.jai.RenderedOp.createRendering(RenderedOp.java:867)
at javax.media.jai.RenderedOp.getRendering(RenderedOp.java:888)
at javax.media.jai.JAI.createNS(JAI.java:1099)
at javax.media.jai.JAI.create(JAI.java:973)
at javax.media.jai.JAI.create(JAI.java:1621)
at com.vs.graphics.concepts.TiffToJpeg.ConvertTiffToJpg(TiffToJpeg.java:30)
at com.vs.graphics.svg.SvgRefresh$1.actionPerformed(SvgRefresh.java:106)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
at java.awt.Component.processMouseEvent(Component.java:6216)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3265)
at java.awt.Component.processEvent(Component.java:5981)
at java.awt.Container.processEvent(Container.java:2041)
at java.awt.Component.dispatchEventImpl(Component.java:4583)
at java.awt.Container.dispatchEventImpl(Container.java:2099)
at java.awt.Component.dispatchEvent(Component.java:4413)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4556)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4220)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4150)
at java.awt.Container.dispatchEventImpl(Container.java:2085)
at java.awt.Window.dispatchEventImpl(Window.java:2475)
at java.awt.Component.dispatchEvent(Component.java:4413)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
Caused by: java.lang.OutOfMemoryError: Java heap space
at java.awt.image.DataBufferByte.<init>(DataBufferByte.java:42)
at java.awt.image.Raster.createInterleavedRaster(Raster.java:253)
at java.awt.image.Raster.createInterleavedRaster(Raster.java:194)
at com.sun.media.jai.codecimpl.JPEGImageEncoder.encode(JPEGImageEncoder.java:182)
at com.sun.media.jai.opimage.EncodeRIF.create(EncodeRIF.java:70)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at javax.media.jai.FactoryCache.invoke(FactoryCache.java:122)
at javax.media.jai.OperationRegistry.invokeFactory(OperationRegistry.java:1674)
at javax.media.jai.ThreadSafeOperationRegistry.invokeFactory(ThreadSafeOperationRegistry.java:473)
at javax.media.jai.registry.RIFRegistry.create(RIFRegistry.java:332)
at com.sun.media.jai.opimage.FileStoreRIF.create(FileStoreRIF.java:138)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at javax.media.jai.FactoryCache.invoke(FactoryCache.java:122)
at javax.media.jai.OperationRegistry.invokeFactory(OperationRegistry.java:1674)
at javax.media.jai.ThreadSafeOperationRegistry.invokeFactory(ThreadSafeOperationRegistry.java:473)
at javax.media.jai.registry.RIFRegistry.create(RIFRegistry.java:332)
at javax.media.jai.RenderedOp.createInstance(RenderedOp.java:819)
at javax.media.jai.RenderedOp.createRendering(RenderedOp.java:867)
at javax.media.jai.RenderedOp.getRendering(RenderedOp.java:888)
at javax.media.jai.JAI.createNS(JAI.java:1099)
at javax.media.jai.JAI.create(JAI.java:973)
at javax.media.jai.JAI.create(JAI.java:1621)
at com.vs.graphics.concepts.TiffToJpeg.ConvertTiffToJpg(TiffToJpeg.java:30)
at com.vs.graphics.svg.SvgRefresh$1.actionPerformed(SvgRefresh.java:106)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318)
Error: One factory fails for the operation "filestore"
Occurs in: javax.media.jai.ThreadSafeOperationRegistry
这是因为内存不足错误。
是否有可用的 Tiled Image Writer 或 Fragment Image Writer 使用它我们将一次只转换图像的一部分，因此我们可以使用可用的普通内存我认为它可能被称为使用图像分割进行转换。
编辑
使用 pngJ 直接编写 png 文件。
我的目的是将 SVG 画布转码为 400 DPI 的 PNG
如果我为此使用PNGTranscoder，它会为提到的图像大小引发内存不足异常。
所以我使用了 TiledImageTranscoder ，它使用以下代码将 SVG 转码为图像。
protected void transcode(Document document, String uri,
TranscoderOutput output) throws TranscoderException {
// Sets up root, curTxf & curAoi
super.transcode(document, uri, output);
Filter f = this.root.getGraphicsNodeRable(true);
RenderContext rc = new RenderContext(curTxf, null, null);
RenderedImage img = f.createRendering(rc);
// prepare the image to be painted
int w = img.getWidth();
int h = img.getHeight();
try {
int bands = img.getSampleModel().getNumBands();
int[] off = new int[bands];
for (int i = 0; i < bands; i++)
off[i] = i;
SampleModel sm = new PixelInterleavedSampleModel(
DataBuffer.TYPE_BYTE, w, (100000 + w - 1) / w, bands, w
* bands, off);
RenderedImage rimg = new FormatRed(GraphicsUtil.wrap(img), sm);
TIFFImageEncoder enc = new TIFFImageEncoder(output
.getOutputStream(), null);
enc.encode(rimg);
} catch (IOException ioe) {
ioe.printStackTrace();
}
}
如您所见，上面的代码最终使用 TIFFImageEncoder 逐步写入磁盘并在我的情况下生成 1.30 GB 的 TIFF 文件。
所以这就是为什么我需要将这个生成的文件转换为 PNG 文件。
我的问题是专门针对@leonbloy
我们可以在这里使用 pngJ 库中的 PNGWriter 直接使用 400 DPI 写入 png 文件而不会出现内存不足的错误，这样我们也可以节省时间并避免不必要的转换。
或者
我们可以用 pngJ 库覆盖PngImageWriter的 writeImage 方法，从而实现我们的目标吗？
谢谢你米希尔帕雷克