将图像的色彩空间从 RGB 转换为 HSV答案

【问题标题】：Converting an image's colorspace from RGB to HSV将图像的色彩空间从 RGB 转换为 HSV
【发布时间】：2014-11-28 07:45:23
【问题描述】：

我正在尝试将 rgb 图像的色彩空间从 RGB 转换为 HSV。我使用了下面的代码：

public class Main {
   public static void main( String[] args )
   {
   try{
       System.loadLibrary( Core.NATIVE_LIBRARY_NAME );
       File input = new File("H:/Development/workspace/label.png");
       BufferedImage image = ImageIO.read(input);   
       byte[] data=extractBytes(image);     
       Mat mat = new Mat(image.getHeight(),image.getWidth(),CvType.CV_8UC2);
       mat.put(0, 0, data);

       Mat mat1 = new Mat(image.getHeight(),image.getWidth(),CvType.CV_8UC2);
       Imgproc.cvtColor(mat, mat1, Imgproc.COLOR_RGB2HSV);

       byte[] data1 = new byte[mat1.rows()*mat1.cols()*(int)(mat1.elemSize())];
       mat1.get(0, 0, data1);
       BufferedImage image1 = new BufferedImage(mat1.cols(), mat1.rows(), 5);
       image1.getRaster().setDataElements(0,0,mat1.cols(),mat1.rows(),data1);

       File ouptut = new File("H:/Development/workspace/label_hsv.png");
       ImageIO.write(image1, "png", ouptut);
      } catch (Exception e) {
         // System.out.println("Failed");
          System.out.println("Error: " + e.getMessage());
          e.printStackTrace();
        }
   }
   public static byte[] extractBytes (BufferedImage bufferedImage) throws IOException {
       WritableRaster raster = bufferedImage .getRaster();
       DataBufferByte data   = (DataBufferByte) raster.getDataBuffer();

       return ( data.getData() );
      }
}

但它失败并出现一些错误：断言失败

OpenCV Error: Assertion failed ((scn == 3 || scn == 4) && (depth == CV_8U || depth == CV_32F)) in cv::cvtColor, file ..\..\..\..\opencv\modules\imgproc\src\color.cpp, line 3959
CvException [org.opencv.core.CvException: cv::Exception: ..\..\..\..\opencv\modules\imgproc\src\color.cpp:3959: error: (-215) (scn == 3 || scn == 4) && (depth == CV_8U || depth == CV_32F) in function cv::cvtColor
]
    at org.opencv.imgproc.Imgproc.cvtColor_1(Native Method)
    at org.opencv.imgproc.Imgproc.cvtColor(Imgproc.java:4598)
    at com.pradeep.exper.Main.main(Main.java:28)

任何帮助为什么会发生？

【问题讨论】：

CvType.CV_8UC2 // 应该是 CvType.CV_8UC3。还有，为什么不用Highgui.imread()，省去很多位图转换呢？
你也只需要 Mat mat1 = new Mat();用于 cvtColor 的输出

标签： java opencv image-processing

【解决方案1】：

到目前为止，您的程序可以归结为一个简单的：

public class Main {
   public static void main( String[] args ) {
       System.loadLibrary( Core.NATIVE_LIBRARY_NAME );

       Mat bgr = Highgui.imread("H:/Development/workspace/label.png");
       Mat hsv = new Mat();
       Imgproc.cvtColor(bgr, hsv, Imgproc.COLOR_RGB2HSV);
       Highgui.imwrite("H:/Development/workspace/label_hsv.png");
   }
}

【讨论】：