Question

我正在尝试读取图像并将其输出为新的灰度和棕褐色版本。我已经找到了大部分内容，但转换仅适用于某些图像。对于其他人，它只会导致错误消息：

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: Coordinate out of bounds!
        at sun.awt.image.ByteInterleavedRaster.getDataElements(ByteInterleavedRaster.java:318)
        at java.awt.image.BufferedImage.getRGB(BufferedImage.java:918)
        at ChangeColor.color2gray(ChangeColor.java:64)
        at ChangeColor.main(ChangeColor.java:129)

我认为它与图像的rgb值有关，但我不知道如何调整它以使此代码适用于任何图像。感谢帮助，谢谢。

 import java.awt.Color;
      import java.awt.Graphics2D;
      import java.awt.image.BufferedImage;
      import java.io.File;
      import java.io.IOException;
      import java.net.URL;

      import javax.imageio.IIOImage;
      import javax.imageio.ImageIO;
      import javax.imageio.ImageWriteParam;
      import javax.imageio.ImageWriter;
      import javax.imageio.plugins.jpeg.JPEGImageWriteParam;
      import javax.imageio.stream.ImageOutputStream;

      public class ChangeColor{

        static BufferedImage readImage( String fname ) throws Exception {

        BufferedImage image = ImageIO.read( new File(fname) );
        return( image );
        }

        public static void saveImage( BufferedImage img, File file ) throws IOException {

              ImageWriter      writer = null;
              java.util.Iterator iter = ImageIO.getImageWritersByFormatName("jpg");

              if( iter.hasNext() ){
                  writer = (ImageWriter)iter.next();
              }

              ImageOutputStream ios = ImageIO.createImageOutputStream( file );
              writer.setOutput(ios);

              ImageWriteParam param = new JPEGImageWriteParam( java.util.Locale.getDefault() );
              param.setCompressionMode(ImageWriteParam.MODE_EXPLICIT) ;
              param.setCompressionQuality(0.98f);

              writer.write(null, new IIOImage( img, null, null ), param);

          }


        public static BufferedImage color2gray( BufferedImage inImage ) {

          int            width    = inImage.getWidth();
          int            height   = inImage.getHeight();
          BufferedImage  outImage = new BufferedImage( width, height, BufferedImage.TYPE_3BYTE_BGR );

          for(int i=0; i<height; i++){
              for(int j=0; j<width; j++){
                {
                    int pic= inImage.getRGB(i,j);
                    int in_r = ((pic>>16) & 0xFF);
                    int in_g = ((pic>>8) & 0xFF);
                    int in_b = (pic & 0xFF);
                    float gray = (float)(in_r * 0.2126 + in_g * 0.7152 + in_b * 0.0722)/256;
                    Color color = new Color (gray, gray, gray);
                    int RGB = color.getRGB();
                    outImage.setRGB (i,j,RGB);
                }

                 }
            }

          return( outImage );
        }


        public static BufferedImage color2sepia( BufferedImage inImage ) {

          int            width    = inImage.getWidth();
          int            height   = inImage.getHeight();
          BufferedImage  outImage = new BufferedImage( width, height, BufferedImage.TYPE_3BYTE_BGR );

          for(int i=0; i<height; i++){
              for(int j=0; j<width; j++){
                {
                    int pic= inImage.getRGB(i,j);
                    int in_r = ((pic>>16) & 0xFF);
                    int in_g = ((pic>>8) & 0xFF);
                    int in_b = (pic & 0xFF);
                    float out_r = (float)(((in_r * .393) + (in_g *.769) + (in_b * .189))/256);
                    if (out_r>1)
                        out_r = 1;
                    float out_g = (float)(((in_r * .349) + (in_g *.686) + (in_b * .168))/256);
                    if (out_g>1)
                        out_g = 1;
                    float out_b = (float)(((in_r * .272) + (in_g *.534) + (in_b * .131))/256);
                    if (out_b>1)
                        out_b = 1;
                    Color color = new Color (out_r, out_g, out_b);
                    int RGB = color.getRGB();
                    outImage.setRGB (i,j,RGB);
                }
                }
              }

          return( outImage );
        }

        public static void main(String[] args) throws Exception {

          BufferedImage colorImage, grayImage, sepiaImage;

          if (args.length != 1)
            System.out.println( "usage is: java ChangeColor filename" );
          else
          {
              colorImage = readImage  ( args[0] );
        grayImage  = color2gray ( colorImage );
        sepiaImage = color2sepia( colorImage );

        saveImage( grayImage,  new File( "gray" + args[0] ) );
        saveImage( sepiaImage, new File( "sepia"+ args[0] ) );
          }
        }

      }

Answer 1

您的错误在这里：

      for(int i=0; i<height; i++){
          for(int j=0; j<width; j++){
            {
                int pic= inImage.getRGB(i,j);

你已经交换了宽度和高度，所以除非图像是一个完美的正方形，否则你会得到你发布的错误。

Java将图像输出为灰度和棕褐色

1 个答案: