The following common functions can be realized: scaling images, cutting images, image type conversion, color to black and white, text watermark, picture watermark, etc.
The code is as follows Copy the code
import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.color.ColorSpace;
import java.awt.geom.AffineTransform;
import java.awt.image.AffineTransformOp;
import java.awt.image.BufferedImage;
import java.awt.image.ColorConvertOp;
import java.awt.image.CropImageFilter;
import java.awt.image.FilteredImageSource;
import java.awt.image.ImageFilter;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
/**
* Image processing tools:
* Functions: scaling images, cutting images, image type conversion, color to black and white, text watermarks, picture watermarks, etc.
* @author Administrator
*/
public class ImageUtils {
/**
* Several common image formats
*/
public static String IMAGE_TYPE_GIF = "gif";// Graphics Interchange Format
public static String IMAGE_TYPE_JPG = "jpg";// Joint Photographic Experts Group
Public static String IMAGE_TYPE_JPEG = "jpeg"; // Joint Photo Experts Group
public static String IMAGE_TYPE_BMP = "bmp"; // Abbreviation for English Bitmap, which is the standard image file format in the Windows operating system
public static String IMAGE_TYPE_PNG = "png"; // Portable network graphics
public static String IMAGE_TYPE_PSD = "psd"; // Photoshop's special format Photoshop
/**
* Program entry: for testing
* @param args
*/
public static void main(String[] args) {
out out using using ’’s ’ ’ s using ‐ ‐out‐out‐out‐right args) {
using using using using using args. Test OK
using height and width use using using ‐ through using using using using using using out out out out out out out out out Out out out out out out out out ’s to ’s to . / 2-Cut image:
through out through pixel out’’'’’’’’’’’ceoopce’cecerceceps togetherceps togetherceps togethercembcececece rightce rightomp rightce rightomp right right rightomp right right‐‐‐‐‐‐out‐‐outir‐to‐outir‐thir's‐thirty-thir irst. ); // Test OK
// Method 2: Specify the number of rows and columns of the slice
// Method 3: Specify the width and height of the slice
ImageUtils.cut3("e:/abc.jpg", "e:/", 300, 300 ); // Test OK
ImageUtils.convert("e:/abc.jpg", "GIF", "e:/abc_convert.gif");//Test OK
ImageUtils. /abc.jpg "," e: /abc_gray.jpg "); // Test ok
// 5- Add text watermark to the picture:
// Method 1:
.
ImageUtils.pressText2("I am also a watermark text", "e:/abc.jpg", "e:/abc_pressText2.jpg", "Heold", 36, Color.white, 80, 0, 0, 0.5f); //Test OK
ImageUtils.pressImage("e:/abc2.jpg", "e:/abc.jpg", "e:/abc_pressImage.jpg", 0, 0, 0.5f);//Test OK
}
/**
* Scale the image (scaling proportionally)
use using - */
public final static void scale(String srcImageFile, String result,
int scale, boolean flag) {
try {
BufferedImage src = ImageIO.read(new File(srcImageFile)); // 读入文件
int width = src.getWidth(); // 得到源图宽
int height = src.getHeight(); // 得到源图长
if (flag) {// 放大
width = width * scale;
height = height * scale;
} else {// 缩小
width = width / scale;
height = height / scale;
}
Image image = src.getScaledInstance(width, height,
Image.SCALE_DEFAULT);
BufferedImage tag = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);
Graphics g = tag.getGraphics();
g.drawImage(image, 0, 0, null); // 绘制缩小后的图
g.dispose();
ImageIO.write(tag, "JPEG", new File(result));// 输出到文件流
} catch (IOException e) {
e.printStackTrace();
}
}
/**
use using
’ using ’ s srcImageFile ’s-'s srcImageFile
’ to
@param bb Whether filler is needed when the proportion is wrong: true means filler; false means no filler;
*/
public final static void scale2(String srcImageFile, String result, int height, int width, boolean bb) {
try {
double ratio = 0.0; // 缩放比例
File f = new File(srcImageFile);
BufferedImage bi = ImageIO.read(f);
Image itemp = bi.getScaledInstance(width, height, bi.SCALE_SMOOTH);
// 计算比例
if ((bi.getHeight() > height) || (bi.getWidth() > width)) {
if (bi.getHeight() > bi.getWidth()) {
ratio = (new Integer(height)).doubleValue()
/ bi.getHeight();
} else {
ratio = (new Integer(width)).doubleValue() / bi.getWidth();
}
AffineTransformOp op = new AffineTransformOp(AffineTransform
.getScaleInstance(ratio, ratio), null);
itemp = op.filter(bi, null);
}
if (bb) {//补白
BufferedImage image = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);
Graphics2D g = image.createGraphics();
g.setColor(Color.white);
g.fillRect(0, 0, width, height);
if (width == itemp.getWidth(null))
g.drawImage(itemp, 0, (height - itemp.getHeight(null)) / 2,
itemp.getWidth(null), itemp.getHeight(null),
Color.white, null);
else
g.drawImage(itemp, (width - itemp.getWidth(null)) / 2, 0,
itemp.getWidth(null), itemp.getHeight(null),
Color.white, null);
g.dispose();
itemp = image;
}
ImageIO.write((BufferedImage) itemp, "JPEG", new File(result));
} catch (IOException e) {
e.printStackTrace();
}
}
/**
Coordinate Y
* @param width Target slice width
* @param height Target slice height
*/
public final static void cut(String srcImageFile, String result,
int x, int y, int width, int height) {
try {
// 读取源图像
BufferedImage bi = ImageIO.read(new File(srcImageFile));
int srcWidth = bi.getHeight(); // 源图宽度
int srcHeight = bi.getWidth(); // 源图高度
if (srcWidth > 0 && srcHeight > 0) {
Image image = bi.getScaledInstance(srcWidth, srcHeight,
Image.SCALE_DEFAULT);
// 四个参数分别为图像起点坐标和宽高
// 即: CropImageFilter(int x,int y,int width,int height)
ImageFilter cropFilter = new CropImageFilter(x, y, width, height);
Image img = Toolkit.getDefaultToolkit().createImage(
new FilteredImageSource(image.getSource(),
cropFilter));
BufferedImage tag = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
Graphics g = tag.getGraphics();
g.drawImage(img, 0, 0, width, height, null); // 绘制切割后的图
g.dispose();
// 输出为文件
ImageIO.write(tag, "JPEG", new File(result));
}
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* 图像切割（指定切片的行数和列数）
* @param srcImageFile 源图像地址
* @param descDir 切片目标文件夹
* @param rows 目标切片行数。默认2，必须是范围 [1, 20] 之内
* @param cols The number of target slicing columns. Default 2, must be within the range [1, 20]
rows> ;20) rows = 2; // Number of slicing rows
use use using using using using ‐ ‐ through out using through using through using using through through through through out through through through through through through through through ’ s ’ through ’ ’ ‐ ‐ ‐ ‐‐ ‐ ‐ ‐ to File(srcImageFile));
int srcWidth = bi.getHeight(); // Source image width
int srcHeight = bi.getWidth(); // Source image height
if (srcWidth > 0 && srcHeight &g t; 0) {
Image img; int destWidth = srcWidth; //The width of each slice
int destHeight = srcHeight; // The width of each slice Height
. } else {
destWidth = (int) Math.floor(srcWidth / cols) + 1;
}
ight = (int) Math.floor(srcWidth / rows) + 1;
. /Improvement ideas: Can multi-threading be used to speed up cutting? for (int i = 0; i < rows; i++) {
parameters They are image starting point coordinates and wide heights //: cropImageFilter (int x, int y, int width, int height)
CropFilter = New CropimageFilter (J * Destwidth, I * Destheight,
DestWidth, Destheight);
IMG = Toolkit.getDefaultToolkit().createImage(
new FilteredImageSource(image.getSource(), destHeight, , 0, null); // Draw the reduced image
Dir
" + j + ".jpg");
/**
* Image cutting (specify the width and height of the slice)
. Default 200
* @param destHeight target slice height. Default 150
*/
public final static void cut3(String srcImageFile, String descDir,
int destWidth, int destHeight) {
try {
if(destWidth<=0) = 200; // slice width
if(destHeight<=0) destHeight = 150; // Slice height
Read the source image
BufferedImage bi = ImageIO.read(new File(srcImageFile)); Image width
int srcHeight = bi.getWidth(); // Source image height
use using srcHeight ’ s using ImageFilter cropFilter;
Image image = bi.getScaledInstance(srcWidth, srcHeight , Image. SCALE_DEFAULT); if (srcWidth % destWidth == 0) {
cols = srcWidth / destWidth;
If (srcHeight % destHeight == 0) {
{
Cutting speed
; rows; i++) {
mageFilter(int x,int y,int width, int height)
cropFilter = New CropimageFilter (J * Destwidth, I * Destheight,
destWidth, destHeight);
img = Toolkit.getDefaultToolkit().createImage(
new FilteredImageSource(image.getSource(), destHeight, , 0, null); // Draw the reduced image
Dir
" + j + ".jpg");
/**
* 图像类型转换：GIF->JPG、GIF->PNG、PNG->JPG、PNG->GIF(X)、BMP->PNG
* @param srcImageFile 源图像地址
* @param formatName 包含格式非正式名称的 String：如JPG、JPEG、GIF等
* @param destImageFile 目标图像地址
*/
public final static void convert(String srcImageFile, String formatName, String destImageFile) {
try {
File f = new File(srcImageFile);
f.canRead();
f.canWrite();
BufferedImage src = ImageIO.read(f);
ImageIO.write(src, formatName, new File(destImageFile));
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* Convert color to black and white
* @param srcImageFile Source image address
* @param destImageFile Destination image address
*/
public final static void gray(String srcImageFile, String destImageFile) {
try {
BufferedImage src = ImageIO.read(new File(srcImageFile));
ColorSpace cs = ColorSpace.getInstance(ColorSpace.CS_GRAY);
ColorConvertOp op = new ColorConvertOp(cs, null);
src = op.filter(src, null);
ImageIO.write(src, "JPEG", new File(destImageFile));
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* Add text watermark to the picture
* @param pressText watermark text
* @param srcImageFile source image address
* @param destImageFile destination image address
* @param fontName font name of the watermark
* @param fontStyle watermark font style
* @param color font color of the watermark
* @param fontSize font size of the watermark
* @param x correction value
* @param y correction value
* @param alpha transparency: alpha must be within the range [0.0, 1.0] (inclusive) boundary value) a floating point number
*/
public final static void pressText(String pressText,
String srcImageFile, String destImageFile, String fontName,
int fontStyle, Color color, int fontSize,int x,
int y, float alpha) {
try {
File img = new File(srcImageFile);
Image src = ImageIO.read(img);
int width = src.getWidth(null);
int height = src.getHeight(null);
BufferedImage image = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);
Graphics2D g = image.createGraphics();
g.drawImage(src, 0, 0, width, height, null);
g.setColor(color);
g.setFont(new Font(fontName, fontStyle, fontSize));
g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP,
alpha));
// 在指定坐标绘制水印文字
g.drawString(pressText, (width - (getLength(pressText) * fontSize))
/ 2 + x, (height - fontSize) / 2 + y);
g.dispose();
ImageIO.write((BufferedImage) image, "JPEG", new File(destImageFile));// 输出到文件流
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* Add text watermark to the picture
* @param pressText watermark text
* @param srcImageFile source image address
* @param destImageFile destination image address
* @param fontName font name
* @param fontStyle font style
* @param color font Color
* @param fontSize font size
*/
public final static void pressText2(String pressText, String srcImageFile,String destImageFile,
String fontName, int fontStyle, Color color, int fontSize, int x,
int y, float alpha) {
try {
File img = new File(srcImageFile);
Image src = ImageIO.read(img);
int width = src.getWidth(null);
int height = src.getHeight(null);
BufferedImage image = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);
Graphics2D g = image.createGraphics();
g.drawImage(src, 0, 0, width, height, null);
g.setColor(color);
g.setFont(new Font(fontName, fontStyle, fontSize));
g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP,
alpha));
// 在指定坐标绘制水印文字
g.drawString(pressText, (width - (getLength(pressText) * fontSize))
/ 2 + x, (height - fontSize) / 2 + y);
g.dispose();
ImageIO.write((BufferedImage) image, "JPEG", new File(destImageFile));
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* Add image watermark to the picture
* @param pressImg watermark image
* @param srcImageFile source image address
* @param destImageFile destination image address
* @param x correction value. Default is in the middle
* @param y correction value. Default is in the middle
* @param alpha transparency: alpha must be a floating point number within the range [0.0, 1.0] (including boundary values)
*/
public final static void pressImage(String pressImg, String srcImageFile,String destImageFile,
int x, int y, float alpha) {
try {
File img = new File(srcImageFile);
Image src = ImageIO.read(img);
int wideth = src.getWidth(null);
int height = src.getHeight(null);
BufferedImage image = new BufferedImage(wideth, height,
BufferedImage.TYPE_INT_RGB);
Graphics2D g = image.createGraphics();
g.drawImage(src, 0, 0, wideth, height, null);
// 水印文件
Image src_biao = ImageIO.read(new File(pressImg));
int wideth_biao = src_biao.getWidth(null);
int height_biao = src_biao.getHeight(null);
g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP,
alpha));
g.drawImage(src_biao, (wideth - wideth_biao) / 2,
(height - height_biao) / 2, wideth_biao, height_biao, null);
// 水印文件结束
g.dispose();
ImageIO.write((BufferedImage) image, "JPEG", new File(destImageFile));
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* Calculate the length of text (one Chinese character is counted as two characters)
* @param text
* @return
*/
public final static int getLength(String text) {
int length = 0;
for (int i = 0; i < text.length(); i++) {
if (new String(text.charAt(i) + "").getBytes().length > 1) {
length += 2;
} else {
length += 1;
}
}
return length / 2;
}
}
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