【转】Java实现图片等比例压缩 和 精度压缩(保留图片大小)
原文链接
https://my.oschina.net/u/242764/blog/2980538
https://blog.csdn.net/Abubu123/article/details/77099950
package com.bonc.ioc.lmp.common.util; import java.awt.Graphics2D; import java.awt.Rectangle; import java.awt.RenderingHints; import java.awt.geom.AffineTransform; import java.awt.image.BufferedImage; import java.awt.image.ColorModel; import java.awt.image.WritableRaster; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStream; import javax.imageio.ImageIO; import org.junit.Test; /** * 图片工具类,完成图片的截取 * 所有方法返回值均未boolean型 */ public class ImageHelper { /** * 实现图像的等比缩放 * @param source * @param targetW * @param targetH * @return */ private static BufferedImage resize(BufferedImage source, int targetW, int targetH) { // targetW,targetH分别表示目标长和宽 int type = source.getType(); BufferedImage target = null; double sx = (double) targetW / source.getWidth(); double sy = (double) targetH / source.getHeight(); // 这里想实现在targetW,targetH范围内实现等比缩放。如果不需要等比缩放 // 则将下面的if else语句注释即可 if (sx < sy) { sx = sy; targetW = (int) (sx * source.getWidth()); } else { sy = sx; targetH = (int) (sy * source.getHeight()); } if (type == BufferedImage.TYPE_CUSTOM) { // handmade ColorModel cm = source.getColorModel(); WritableRaster raster = cm.createCompatibleWritableRaster(targetW, targetH); boolean alphaPremultiplied = cm.isAlphaPremultiplied(); target = new BufferedImage(cm, raster, alphaPremultiplied, null); } else target = new BufferedImage(targetW, targetH, type); Graphics2D g = target.createGraphics(); // smoother than exlax: g.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BICUBIC); g.drawRenderedImage(source, AffineTransform.getScaleInstance(sx, sy)); g.dispose(); return target; } /** * 实现图像的等比缩放和缩放后的截取, 处理成功返回true, 否则返回false * @param inFilePath 要截取文件的路径 * @param outFilePath 截取后输出的路径 * @param width 要截取宽度 * @param hight 要截取的高度 * @throws Exception */ public static boolean compress(String inFilePath, String outFilePath, int width, int hight) { boolean ret = false; File file = new File(inFilePath); File saveFile = new File(outFilePath); InputStream in = null; try { in = new FileInputStream(file); ret = compress(in, saveFile, width, hight); } catch (FileNotFoundException e) { e.printStackTrace(); ret = false; } finally{ if(null != in){ try { in.close(); } catch (IOException e) { e.printStackTrace(); } } } return ret; } /** * 实现图像的等比缩放和缩放后的截取, 处理成功返回true, 否则返回false * @param in 要截取文件流 * @param outFilePath 截取后输出的路径 * @param width 要截取宽度 * @param hight 要截取的高度 * @throws Exception */ public static boolean compress(InputStream in, File saveFile, int width, int hight) { // boolean ret = false; BufferedImage srcImage = null; try { srcImage = ImageIO.read(in); } catch (IOException e) { e.printStackTrace(); return false; } if (width > 0 || hight > 0) { // 原图的大小 int sw = srcImage.getWidth(); int sh = srcImage.getHeight(); // 如果原图像的大小小于要缩放的图像大小,直接将要缩放的图像复制过去 if (sw > width && sh > hight) { srcImage = resize(srcImage, width, hight); } else { String fileName = saveFile.getName(); String formatName = fileName.substring(fileName .lastIndexOf('.') + 1); try { ImageIO.write(srcImage, formatName, saveFile); } catch (IOException e) { e.printStackTrace(); return false; } return true; } } // 缩放后的图像的宽和高 int w = srcImage.getWidth(); int h = srcImage.getHeight(); // 如果缩放后的图像和要求的图像宽度一样,就对缩放的图像的高度进行截取 if (w == width) { // 计算X轴坐标 int x = 0; int y = h / 2 - hight / 2; try { saveSubImage(srcImage, new Rectangle(x, y, width, hight), saveFile); } catch (IOException e) { e.printStackTrace(); return false; } } // 否则如果是缩放后的图像的高度和要求的图像高度一样,就对缩放后的图像的宽度进行截取 else if (h == hight) { // 计算X轴坐标 int x = w / 2 - width / 2; int y = 0; try { saveSubImage(srcImage, new Rectangle(x, y, width, hight), saveFile); } catch (IOException e) { e.printStackTrace(); return false; } } return true; } /** * 实现图像的等比缩放和缩放后的截取, 处理成功返回true, 否则返回false * @param in 图片输入流 * @param saveFile 压缩后的图片输出流 * @param proportion 压缩比 * @throws Exception */ public static boolean compress(InputStream in, File saveFile, int proportion) { if(null == in ||null == saveFile ||proportion < 1){// 检查参数有效性 //LoggerUtil.error(ImageHelper.class, "--invalid parameter, do nothing!"); return false; } BufferedImage srcImage = null; try { srcImage = ImageIO.read(in); } catch (IOException e) { e.printStackTrace(); return false; } // 原图的大小 int width = srcImage.getWidth() / proportion; int hight = srcImage.getHeight() / proportion; srcImage = resize(srcImage, width, hight); // 缩放后的图像的宽和高 int w = srcImage.getWidth(); int h = srcImage.getHeight(); // 如果缩放后的图像和要求的图像宽度一样,就对缩放的图像的高度进行截取 if (w == width) { // 计算X轴坐标 int x = 0; int y = h / 2 - hight / 2; try { saveSubImage(srcImage, new Rectangle(x, y, width, hight), saveFile); } catch (IOException e) { e.printStackTrace(); return false; } } // 否则如果是缩放后的图像的高度和要求的图像高度一样,就对缩放后的图像的宽度进行截取 else if (h == hight) { // 计算X轴坐标 int x = w / 2 - width / 2; int y = 0; try { saveSubImage(srcImage, new Rectangle(x, y, width, hight), saveFile); } catch (IOException e) { e.printStackTrace(); return false; } } return true; } /** * 实现缩放后的截图 * @param image 缩放后的图像 * @param subImageBounds 要截取的子图的范围 * @param subImageFile 要保存的文件 * @throws IOException */ private static void saveSubImage(BufferedImage image, Rectangle subImageBounds, File subImageFile) throws IOException { if (subImageBounds.x < 0 || subImageBounds.y < 0 || subImageBounds.width - subImageBounds.x > image.getWidth() || subImageBounds.height - subImageBounds.y > image.getHeight()) { //LoggerUtil.error(ImageHelper.class, "Bad subimage bounds"); return; } BufferedImage subImage = image.getSubimage(subImageBounds.x,subImageBounds.y, subImageBounds.width, subImageBounds.height); String fileName = subImageFile.getName(); String formatName = fileName.substring(fileName.lastIndexOf('.') + 1); ImageIO.write(subImage, formatName, subImageFile); } @Test public static void main(String[] args) throws Exception { /** * saveSubImage 截图类的使用 * srcImage 为BufferedImage对象 * Rectangle 为需要截图的长方形坐标 * saveFile 需要保存的路径及名称 * **/ //需要截图的长方形坐标 /*Rectangle rect =new Rectangle(); rect.x=40; rect.y=40; rect.height=160; rect.width=160; InputStream in = null; //需要保存的路径及名称 File saveFile = new File("d:\\ioc\\files\\aaa2.jpg"); //需要进行处理的图片的路径 in = new FileInputStream(new File("d:\\ioc\\files\\aaa.jpg")); BufferedImage srcImage = null; //将输入的数据转为BufferedImage对象 srcImage = ImageIO.read(in); ImageHelper img=new ImageHelper(); img.saveSubImage(srcImage, rect, saveFile);*/ /** * compress 图片缩放类的使用(缩略图) * srcImage 为InputStream对象 * Rectangle 为需要截图的长方形坐标 * proportion 为压缩比例 * **/ InputStream in = null; //缩放后需要保存的路径 File saveFile = new File("d:\\ioc\\files\\aaa2.jpg"); try { //原图片的路径 in = new FileInputStream(new File("d:\\ioc\\files\\aaa.jpg")); if(compress(in, saveFile, 10)){ System.out.println("图片压缩十倍!"); } } catch (Exception e) { e.printStackTrace(); } finally { in.close(); } } }
保留图片大小,压缩图片精度
import javax.imageio.IIOImage; import javax.imageio.ImageIO; import javax.imageio.ImageWriteParam; import javax.imageio.ImageWriter; import java.awt.image.BufferedImage; import java.awt.image.ColorModel; import java.io.*; import java.util.Iterator; /** * @author: Supermap·F * @descripition: 图片压缩,保留图片尺寸大小,压缩精度 * @date: created in 18:46 2020/8/20 * @modify: Copyright (c) Supermap All Rights Reserved. */ public class ImgUtil { public static byte[] compressPictureByQality(byte[] imgByte, float qality){ byte[] imgBytes = null; BufferedImage resultImage = null; try { ByteArrayInputStream byteInput = new ByteArrayInputStream(imgByte); BufferedImage image = ImageIO.read(byteInput); //如果图片为空,返回null if (image == null){ return null; } //得到指定的format图片的writer(迭代器) Iterator<ImageWriter> iter = ImageIO.getImageWritersByFormatName("jpeg"); //得到writer ImageWriter writer = (ImageWriter) iter.next(); //得到指定writer的输出参数设置 ImageWriteParam iwp = writer.getDefaultWriteParam(); //设置是否可以压缩 iwp.setCompressionMode(ImageWriteParam.MODE_EXPLICIT); //设置压缩质量参数 iwp.setCompressionQuality(qality); iwp.setProgressiveMode(ImageWriteParam.MODE_DISABLED); ColorModel colorModel = ColorModel.getRGBdefault(); //指定压缩式使用的色彩模式 iwp.setDestinationType(new javax.imageio.ImageTypeSpecifier(colorModel,colorModel.createCompatibleSampleModel(16,16))); //开始打包图片,写入byte[] //取的内存输出流 ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream(); IIOImage iImage = new IIOImage(image, null, null); //ImageWriter 中用来接收writer信息的output要求必须是ImageOutput writer.setOutput(ImageIO.createImageOutputStream(byteArrayOutputStream)); writer.write(null, iImage, iwp); imgBytes = byteArrayOutputStream.toByteArray(); ByteArrayInputStream byteInputs = new ByteArrayInputStream(imgBytes); resultImage = ImageIO.read(byteInputs); }catch (IOException e){ System.out.println("错误"); e.printStackTrace(); } return imgBytes; } /** * 图片压缩 * @param image 图片 * @param qality * @return * @throws IOException */ public static BufferedImage compressPictureByQalityV2(BufferedImage image, float qality) { byte[] imgBytes = null; BufferedImage resultImage = null; try { // ByteArrayInputStream byteInput = new ByteArrayInputStream(imgByte); // BufferedImage image = ImageIO.read(byteInput); //如果图片为空,返回null if (image == null){ return null; } //得到指定的format图片的writer(迭代器) Iterator<ImageWriter> iter = ImageIO.getImageWritersByFormatName("jpeg"); //得到writer ImageWriter writer = (ImageWriter) iter.next(); //得到指定writer的输出参数设置 ImageWriteParam iwp = writer.getDefaultWriteParam(); //设置是否可以压缩 iwp.setCompressionMode(ImageWriteParam.MODE_EXPLICIT); //设置压缩质量参数 iwp.setCompressionQuality(qality); iwp.setProgressiveMode(ImageWriteParam.MODE_DISABLED); ColorModel colorModel = ColorModel.getRGBdefault(); //指定压缩式使用的色彩模式 iwp.setDestinationType(new javax.imageio.ImageTypeSpecifier(colorModel,colorModel.createCompatibleSampleModel(16,16))); //开始打包图片,写入byte[] //取的内存输出流 ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream(); IIOImage iImage = new IIOImage(image, null, null); //ImageWriter 中用来接收writer信息的output要求必须是ImageOutput writer.setOutput(ImageIO.createImageOutputStream(byteArrayOutputStream)); writer.write(null, iImage, iwp); imgBytes = byteArrayOutputStream.toByteArray(); ByteArrayInputStream byteInputs = new ByteArrayInputStream(imgBytes); resultImage = ImageIO.read(byteInputs); }catch (IOException e){ System.out.println("错误"); e.printStackTrace(); } return resultImage; } }