等比例压缩图片

最新推荐文章于 2022-06-23 15:09:00 发布

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package com.baitw.struts.utils;

import java.awt.image.BufferedImage;
import java.io.File;
import javax.imageio.ImageIO;

/**
 * 
 * 生成等比例高质量缩略图
 * 
 * */

public class ScaleImage {

	private int width;

	private int height;

	private int scaleWidth;

	double support = (double) 3.0;

	double PI = (double) 3.14159265358978;

	double[] contrib;

	double[] normContrib;

	double[] tmpContrib;

	int startContrib, stopContrib;

	int nDots;

	int nHalfDots;

	/**
	 * Start: Use Lanczos filter to replace the original algorithm for image
	 * scaling. Lanczos improves quality of the scaled image modify by :blade
	 **/

	// fromFileStr原图片地址,saveToFileStr生成缩略图地址,formatWideth生成图片宽度,formatHeight高度
	public void saveImageAsJpg(String fromFileStr, String saveToFileStr,
			int formatWideth, int formatHeight) throws Exception {
		BufferedImage srcImage;
		File saveFile = new File(saveToFileStr);
		File fromFile = new File(fromFileStr);
		srcImage = javax.imageio.ImageIO.read(fromFile); // construct image
		int imageWideth = srcImage.getWidth(null);
		int imageHeight = srcImage.getHeight(null);
		int changeToWideth = 0;
		int changeToHeight = 0;
		if (imageWideth > 0 && imageHeight > 0) {
			// flag=true;
			if (imageWideth / imageHeight >= formatWideth / formatHeight) {
				if (imageWideth > formatWideth) {
					changeToWideth = formatWideth;
					changeToHeight = (imageHeight * formatWideth) / imageWideth;
				} else {
					changeToWideth = imageWideth;
					changeToHeight = imageHeight;
				}
			} else {
				if (imageHeight > formatHeight) {
					changeToHeight = formatHeight;
					changeToWideth = (imageWideth * formatHeight) / imageHeight;
				} else {
					changeToWideth = imageWideth;
					changeToHeight = imageHeight;
				}
			}
		}

		srcImage = imageZoomOut(srcImage, changeToWideth, changeToHeight);
		ImageIO.write(srcImage, "JPEG", saveFile);
	}

	public BufferedImage imageZoomOut(BufferedImage srcBufferImage, int w, int h) {
		width = srcBufferImage.getWidth();
		height = srcBufferImage.getHeight();
		scaleWidth = w;

		if (DetermineResultSize(w, h) == 1) {
			return srcBufferImage;
		}
		CalContrib();
		BufferedImage pbOut = HorizontalFiltering(srcBufferImage, w);
		BufferedImage pbFinalOut = VerticalFiltering(pbOut, h);
		return pbFinalOut;
	}

	 //决定图像尺寸

	private int DetermineResultSize(int w, int h) {
		double scaleH, scaleV;
		scaleH = (double) w / (double) width;
		scaleV = (double) h / (double) height;
		// 需要判断一下scaleH，scaleV，不做放大操作
		if (scaleH >= 1.0 && scaleV >= 1.0) {
			return 1;
		}
		return 0;

	} // end of DetermineResultSize()

	private double Lanczos(int i, int inWidth, int outWidth, double Support) {
		double x;

		x = (double) i * (double) outWidth / (double) inWidth;

		return Math.sin(x * PI) / (x * PI) * Math.sin(x * PI / Support)
				/ (x * PI / Support);

	}

	private void CalContrib() {
		nHalfDots = (int) ((double) width * support / (double) scaleWidth);
		nDots = nHalfDots * 2 + 1;
		try {
			contrib = new double[nDots];
			normContrib = new double[nDots];
			tmpContrib = new double[nDots];
		} catch (Exception e) {
			System.out.println("init   contrib,normContrib,tmpContrib" + e);
		}

		int center = nHalfDots;
		contrib[center] = 1.0;

		double weight = 0.0;
		int i = 0;
		for (i = 1; i <= center; i++) {
			contrib[center + i] = Lanczos(i, width, scaleWidth, support);
			weight += contrib[center + i];
		}

		for (i = center - 1; i >= 0; i--) {
			contrib[i] = contrib[center * 2 - i];
		}

		weight = weight * 2 + 1.0;

		for (i = 0; i <= center; i++) {
			normContrib[i] = contrib[i] / weight;
		}

		for (i = center + 1; i < nDots; i++) {
			normContrib[i] = normContrib[center * 2 - i];
		}
	} // end of CalContrib()

	// 处理边缘
	private void CalTempContrib(int start, int stop) {
		double weight = 0;

		int i = 0;
		for (i = start; i <= stop; i++) {
			weight += contrib[i];
		}

		for (i = start; i <= stop; i++) {
			tmpContrib[i] = contrib[i] / weight;
		}

	} // end of CalTempContrib()

	private int GetRedValue(int rgbValue) {
		int temp = rgbValue & 0x00ff0000;
		return temp >> 16;
	}

	private int GetGreenValue(int rgbValue) {
		int temp = rgbValue & 0x0000ff00;
		return temp >> 8;
	}

	private int GetBlueValue(int rgbValue) {
		return rgbValue & 0x000000ff;
	}

	private int ComRGB(int redValue, int greenValue, int blueValue) {

		return (redValue << 16) + (greenValue << 8) + blueValue;
	}

	// 行水平滤波
	private int HorizontalFilter(BufferedImage bufImg, int startX, int stopX,
			int start, int stop, int y, double[] pContrib) {
		double valueRed = 0.0;
		double valueGreen = 0.0;
		double valueBlue = 0.0;
		int valueRGB = 0;
		int i, j;

		for (i = startX, j = start; i <= stopX; i++, j++) {
			valueRGB = bufImg.getRGB(i, y);

			valueRed += GetRedValue(valueRGB) * pContrib[j];
			valueGreen += GetGreenValue(valueRGB) * pContrib[j];
			valueBlue += GetBlueValue(valueRGB) * pContrib[j];
		}

		valueRGB = ComRGB(Clip((int) valueRed), Clip((int) valueGreen),
				Clip((int) valueBlue));
		return valueRGB;

	} // end of HorizontalFilter()

	// 图片水平滤波
	private BufferedImage HorizontalFiltering(BufferedImage bufImage, int iOutW) {
		int dwInW = bufImage.getWidth();
		int dwInH = bufImage.getHeight();
		int value = 0;
		BufferedImage pbOut = new BufferedImage(iOutW, dwInH,
				BufferedImage.TYPE_INT_RGB);

		for (int x = 0; x < iOutW; x++) {

			int startX;
			int start;
			int X = (int) (((double) x) * ((double) dwInW) / ((double) iOutW) + 0.5);
			int y = 0;

			startX = X - nHalfDots;
			if (startX < 0) {
				startX = 0;
				start = nHalfDots - X;
			} else {
				start = 0;
			}

			int stop;
			int stopX = X + nHalfDots;
			if (stopX > (dwInW - 1)) {
				stopX = dwInW - 1;
				stop = nHalfDots + (dwInW - 1 - X);
			} else {
				stop = nHalfDots * 2;
			}

			if (start > 0 || stop < nDots - 1) {
				CalTempContrib(start, stop);
				for (y = 0; y < dwInH; y++) {
					value = HorizontalFilter(bufImage, startX, stopX, start,
							stop, y, tmpContrib);
					pbOut.setRGB(x, y, value);
				}
			} else {
				for (y = 0; y < dwInH; y++) {
					value = HorizontalFilter(bufImage, startX, stopX, start,
							stop, y, normContrib);
					pbOut.setRGB(x, y, value);
				}
			}
		}

		return pbOut;

	} // end of HorizontalFiltering()

	private int VerticalFilter(BufferedImage pbInImage, int startY, int stopY,
			int start, int stop, int x, double[] pContrib) {
		double valueRed = 0.0;
		double valueGreen = 0.0;
		double valueBlue = 0.0;
		int valueRGB = 0;
		int i, j;

		for (i = startY, j = start; i <= stopY; i++, j++) {
			valueRGB = pbInImage.getRGB(x, i);

			valueRed += GetRedValue(valueRGB) * pContrib[j];
			valueGreen += GetGreenValue(valueRGB) * pContrib[j];
			valueBlue += GetBlueValue(valueRGB) * pContrib[j];
			// System.out.println(valueRed+"->"+Clip((int)valueRed)+"<-");
			//   
			// System.out.println(valueGreen+"->"+Clip((int)valueGreen)+"<-");
			// System.out.println(valueBlue+"->"+Clip((int)valueBlue)+"<-"+"-->");
		}

		valueRGB = ComRGB(Clip((int) valueRed), Clip((int) valueGreen),
				Clip((int) valueBlue));
		// System.out.println(valueRGB);
		return valueRGB;

	} // end of VerticalFilter()

	private BufferedImage VerticalFiltering(BufferedImage pbImage, int iOutH) {
		int iW = pbImage.getWidth();
		int iH = pbImage.getHeight();
		int value = 0;
		BufferedImage pbOut = new BufferedImage(iW, iOutH,
				BufferedImage.TYPE_INT_RGB);

		for (int y = 0; y < iOutH; y++) {

			int startY;
			int start;
			int Y = (int) (((double) y) * ((double) iH) / ((double) iOutH) + 0.5);

			startY = Y - nHalfDots;
			if (startY < 0) {
				startY = 0;
				start = nHalfDots - Y;
			} else {
				start = 0;
			}

			int stop;
			int stopY = Y + nHalfDots;
			if (stopY > (int) (iH - 1)) {
				stopY = iH - 1;
				stop = nHalfDots + (iH - 1 - Y);
			} else {
				stop = nHalfDots * 2;
			}

			if (start > 0 || stop < nDots - 1) {
				CalTempContrib(start, stop);
				for (int x = 0; x < iW; x++) {
					value = VerticalFilter(pbImage, startY, stopY, start, stop,
							x, tmpContrib);
					pbOut.setRGB(x, y, value);
				}
			} else {
				for (int x = 0; x < iW; x++) {
					value = VerticalFilter(pbImage, startY, stopY, start, stop,
							x, normContrib);
					pbOut.setRGB(x, y, value);
				}
			}

		}

		return pbOut;

	} // end of VerticalFiltering()

	int Clip(int x) {
		if (x < 0)
			return 0;
		if (x > 255)
			return 255;
		return x;
	}
}

package com.baitw.struts.action;


import java.io.File;
import java.util.Date;

import org.apache.struts2.ServletActionContext;

import com.baitw.dao.ActivityDao;
import com.baitw.dao.CardTypeDao;
import com.baitw.dao.ImageDao;
import com.baitw.dao.UserDao;
import com.baitw.hibernate.entity.TActivity;
import com.opensymphony.xwork2.ActionSupport;

/**
 * 
 * 添加活动
 * 
 * */

public class AddActivity extends ActionSupport {


	private String title;
	private Date begintime;
	private Date endtime;
	private String content;
	private Boolean state;
	private Date createtime;
	private Long cardTypeid;
	private String username;
	private ActivityDao activityDao;
	private CardTypeDao  cardTypeDao;
	private UserDao userDao;
	/*-----------------------------------------------*/
	private String picture;

	private File upload;
	private String uploadContextType;
	private String uploadFileName;
	private String savePath;

	private ImageDao imageDao;

	private int width;
	private int height;

	public void setImageDao(ImageDao imageDao) {
		this.imageDao = imageDao;
	}

	public File getUpload() {
		return upload;
	}

	public void setUpload(File upload) {
		this.upload = upload;
	}

	public String getUploadContextType() {
		return uploadContextType;
	}

	public void setUploadContextType(String uploadContextType) {
		this.uploadContextType = uploadContextType;
	}

	public String getUploadFileName() {
		return uploadFileName;
	}

	public void setUploadFileName(String uploadFileName) {
		this.uploadFileName = uploadFileName;
	}

	public String getSavePath() {
		return ServletActionContext.getRequest().getRealPath(savePath);
	}

	public void setSavePath(String savePath) {
		this.savePath = savePath;
	}
	/*-----------------------------------------------*/

	public String getPicture() {
		return picture;
	}

	public void setPicture(String picture) {
		this.picture = picture;
	}

	public void setUserDao(UserDao userDao) {
		this.userDao = userDao;
	}

	public void setCardTypeDao(CardTypeDao cardTypeDao) {
		this.cardTypeDao = cardTypeDao;
	}

	public String getUsername() {
		return username;
	}

	public void setUsername(String username) {
		this.username = username;
	}

	public String getTitle() {
		return title;
	}

	public void setTitle(String title) {
		this.title = title;
	}

	public Date getBegintime() {
		return begintime;
	}

	public void setBegintime(Date begintime) {
		this.begintime = begintime;
	}

	public Date getEndtime() {
		return endtime;
	}

	public void setEndtime(Date endtime) {
		this.endtime = endtime;
	}

	public String getContent() {
		return content;
	}

	public void setContent(String content) {
		this.content = content;
	}

	public Boolean getState() {
		return state;
	}

	public void setState(Boolean state) {
		this.state = state;
	}

	public Date getCreatetime() {
		return createtime;
	}

	public void setCreatetime(Date createtime) {
		this.createtime = createtime;
	}

	public Long getCardTypeid() {
		return cardTypeid;
	}

	public void setCardTypeid(Long cardTypeid) {
		this.cardTypeid = cardTypeid;
	}

	public ActivityDao getActivityDao() {
		return activityDao;
	}

	public void setActivityDao(ActivityDao activityDao) {
		this.activityDao = activityDao;
	}

	@Override
	public String execute() throws Exception {
		// TODO Auto-generated method stub

		TActivity activity=new TActivity();
		activity.setTitle(title);
		activity.setTCardType(cardTypeDao.getTCardType(cardTypeid.toString()));
		activity.setCreatetime(createtime);
		activity.setBegintime(begintime);
		activity.setEndtime(endtime);
		activity.setContent(content);
		activity.setLogo(savePath+"/"+uploadFileName);
		activity.setLogo(picture);
		activity.setState(true);
		activity.setTUser(userDao.getUserEntity(username));

		imageDao.UploadOriginalImage(upload, 
				ServletActionContext.getRequest().getRealPath(savePath), 
				uploadFileName);

		width=400;height=300;
		String fileType = uploadFileName.substring(uploadFileName.lastIndexOf("."));
		imageDao.formatImage(ServletActionContext.getRequest().getRealPath(savePath)
				+"\\"+uploadFileName, 
				ServletActionContext.getRequest().getRealPath(savePath)
				+"\\"+uploadFileName+"_"+width+"_"+height+fileType, 
				width, 
				height);

		return activityDao.addActivity(activity);
	}

	public String loadAddPage() throws Exception{

		return "loadAddPage";
	}
}