如何使用Java在ImageJ2中将图像从8位转换为RGB

Question

我试图直接使用来自Java的ImageJ2来创建来自输入图像的二值化图像。

A的我的代码有些工作版本是这样的：

final File file = new File("input.png"); 

try { 
    DefaultDataTypeService dataTypeService = new DefaultDataTypeService(); 
    Dataset dataset = imageJ.dataset().open(file.getAbsolutePath()); 
    Img inputImg = dataset.getImgPlus(); 

    PluginInfo pluginInfo = imageJ.plugin().getPlugin(Binarize.class); 
    Binarize binarizeOp = (Binarize) pluginInfo.createInstance(); 
    binarizeOp.setContext(imageJ.getContext()); 
    binarizeOp.setChangeInput(true); 
    binarizeOp.setFillMaskBackground(true); 
    binarizeOp.setFillMaskForeground(true); 
    binarizeOp.setInputData(dataset); 
    binarizeOp.setInputMask(null); 
    binarizeOp.setMaskColor(Binarize.WHITE); 
    binarizeOp.setMaskPixels(Binarize.INSIDE); 
    binarizeOp.setThresholdEachPlane(false); 
    binarizeOp.setDefaultThresholdMethod(); 
    binarizeOp.run(); 

    dataset.rgbChange(); 
    DefaultDatasetService defaultDatasetService = new DefaultDatasetService(); 
    Img outputImg = dataset.getImgPlus(); 
    outputImg = outputImg.factory().imgFactory(new UnsignedByteType()).create(outputImg,new UnsignedByteType()); 
    Dataset outputDataset = defaultDatasetService.create(outputImg); 
    imageJ.dataset().save(outputDataset,"input_binary.png"); 

} catch (IOException e) { 
    e.printStackTrace(); 
} catch (InstantiableException e) { 
    e.printStackTrace(); 
} catch (IncompatibleTypeException e) { 
    e.printStackTrace(); 
} 

运行这段代码，我有一个“input_binary.png”的问题将完全黑色，行为我可以重现使用ImageJ的客户端应用程序。

我在客户端需要做的是将图像类型从“8位颜色”更改为“RGB颜色”。但我无法弄清楚如何使用当前版本的net.imagej库在Java中进行重现。

我知道这将有可能使用1.x库，但我想使用2.x.

任何帮助将不胜感激。

Answer 1

你得到，因为这个黑色影像：。

outputImg = outputImg.factory（）imgFactory（新UnsignedByteType（））创建（outputImg，新UnsignedByteType（））;

这仅仅是您的源代码的copying the dimensionality，而不是它的值。

其他一些关键点：

• 这是有从上下文而不是手动构造派生的上下文对象（例如服务）的最佳实践。
• Binarize命令有一个数据集输出，所以没必要去数据集> ImgPlus>数据集
• 如果您确实想写出数据集，您需要将Binarize输出的BitType转换为支持的数据。

有关运行Binarize，获取输出，将其转换并写出的示例，请参阅下面的示例。希望有所帮助！

public static void main(String... args) { 
    final File file = new File("inpath.png"); 
    final File out = new File("outpath.png"); 

    // This is just sugar for the point of illustration. 
    // The purpose here is just to have access to a Context 
    ImageJ imagej = new ImageJ(); 

    // Cache the context for future use. 
    Context context = imagej.getContext(); 

    try { 
     // Use the context to get the services we want to ensure they are all 
     // properly initialized. 
     // If this was a Command these could all be @Parameters to be populated 
     // automatically. 
     DatasetService datasetService = context.getService(DatasetService.class); 
     CommandService commandService = context.getService(CommandService.class); 
     DatasetIOService datasetIOService = 
      context.getService(DatasetIOService.class); 

     Dataset input = datasetIOService.open(file.getAbsolutePath()); 

     // Start the command 
     Future<CommandModule> future = 
      commandService.run(Binarize.class, true, "inputData", input); 

     // Get the command output 
     Dataset binarized = (Dataset) future.get().getOutput("outputMask"); 

     // The output type is a binary image which, at the moment, needs to be 
     // explicitly converted to something that can be written out. 
     // Adapted from: 
     // http://fiji.sc/ImgLib2_Examples#Example_2c_-_Generic_copying_of_image_data 
     Img inputImg = input.getImgPlus().getImg(); 
     Img outputImg = binarized.getImgPlus().getImg(); 
     Img typedImg = 
      inputImg.factory().create(inputImg, inputImg.firstElement()); 
     scale(outputImg, typedImg); 

     Dataset output = datasetService.create(typedImg); 

     // Save the output dataset 
     datasetIOService.save(output, out.getAbsolutePath()); 
    } 
    catch (IOException exc) { 
     exc.printStackTrace(); 
    } 
    catch (InterruptedException exc) { 
     exc.printStackTrace(); 
    } 
    catch (ExecutionException exc) { 
     exc.printStackTrace(); 
    } 
    finally { 
     // Dispose of the context to shut down 
     context.dispose(); 
    } 

} 

public static <T extends IntegerType<T>> void scale(
    final RandomAccessible<BitType> source, final IterableInterval<T> target) 
{ 
    // create a cursor that automatically localizes itself on every move 
    Cursor<T> targetCursor = target.localizingCursor(); 
    RandomAccess<BitType> sourceRandomAccess = source.randomAccess(); 
    // iterate over the input cursor 
    while (targetCursor.hasNext()) {\ 
     // move input cursor forward 
     targetCursor.fwd(); 
     // set the output cursor to the position of the input cursor 
     sourceRandomAccess.setPosition(targetCursor); 
     // set the value of this pixel of the output image 
     BitType b = sourceRandomAccess.get(); 
     if (b.get()) { 
      targetCursor.get().setOne(); 
     } 
     else { 
      targetCursor.get().setZero(); 
     } 
    } 
}