这个代码是我在网上找的,可以运行。 package com.pb.util; import com.sun.image.codec.jpeg.JPEGCodec; import com.sun.image.codec.jpeg.JPEGImageEncoder; import java.awt.Transparency; import java.awt.color.ColorSpace; import java.awt.image.BufferedImage; import java.awt.image.ColorModel; import java.awt.image.ComponentColorModel; import java.awt.image.DataBuffer; import java.awt.image.DataBufferByte; import java.awt.image.Raster; import java.awt.image.WritableRaster; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.util.Iterator; import javax.imageio.IIOException; import javax.imageio.ImageIO; import javax.imageio.ImageReader; import javax.imageio.stream.ImageInputStream; /** * 把cmyk格式图片转换为RGB格式 * @author Administrator * */ public class CMYK { public void readImage(String filename) throws IOException { File file = new File(filename); ImageInputStream input = ImageIO.createImageInputStream(file); Iterator readers = ImageIO.getImageReaders(input); if(readers == null || !readers.hasNext()) { throw new RuntimeException("1 No ImageReaders found"); } ImageReader reader = (ImageReader) readers.next(); reader.setInput(input); String format = reader.getFormatName() ; BufferedImage image; if ( "JPEG".equalsIgnoreCase(format) ||"JPG".equalsIgnoreCase(format) ) { try { // 尝试读取图片 (包括颜色的转换). image = reader.read(0); //RGB } catch (IIOException e) { // 读取Raster (没有颜色的转换). Raster raster = reader.readRaster(0, null);//CMYK image = createJPEG4(raster); } image.getGraphics().drawImage(image, 0, 0, null); //String newfilename = filename.substring(0,filename.lastIndexOf("."))+"_rgb"+filename.substring(filename.lastIndexOf(".")); String newfilename = filename; File newFile = new File(newfilename); FileOutputStream out = new FileOutputStream(newFile); JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out); encoder.encode(image); out.flush(); out.close(); } } private static BufferedImage createJPEG4(Raster raster) { int w = raster.getWidth(); int h = raster.getHeight(); byte[] rgb = new byte[w * h * 3]; //彩色空间转换 float[] Y = raster.getSamples(0, 0, w, h, 0, (float[]) null); float[] Cb = raster.getSamples(0, 0, w, h, 1, (float[]) null); float[] Cr = raster.getSamples(0, 0, w, h, 2, (float[]) null); float[] K = raster.getSamples(0, 0, w, h, 3, (float[]) null); for (int i = 0, imax = Y.length, base = 0; i < imax; i++, base += 3) { float k = 220 - K[i], y = 255 - Y[i], cb = 255 - Cb[i], cr = 255 - Cr[i]; double val = y + 1.402 * (cr - 128) - k; val = (val - 128) * .65f + 128; rgb[base] = val < 0.0 ? (byte) 0 : val > 255.0 ? (byte) 0xff : (byte) (val + 0.5); val = y - 0.34414 * (cb - 128) - 0.71414 * (cr - 128) - k; val = (val - 128) * .65f + 128; rgb[base + 1] = val < 0.0 ? (byte) 0 : val > 255.0 ? (byte) 0xff : (byte) (val + 0.5); val = y + 1.772 * (cb - 128) - k; val = (val - 128) * .65f + 128; rgb[base + 2] = val < 0.0 ? (byte) 0 : val > 255.0 ? (byte) 0xff : (byte) (val + 0.5); } raster = Raster.createInterleavedRaster(new DataBufferByte(rgb, rgb.length), w, h, w * 3, 3, new int[]{0, 1, 2}, null); ColorSpace cs = ColorSpace.getInstance(ColorSpace.CS_sRGB); ColorModel cm = new ComponentColorModel(cs, false, true, Transparency.OPAQUE, DataBuffer.TYPE_BYTE); return new BufferedImage(cm, (WritableRaster) raster, true, null); } //测试 public static void main(String[] args) throws IOException { String filename = "d:/2015.jpg"; CMYK cm = new CMYK(); cm.readImage(filename); } } |
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