java image compression tool class
- 2020-06-03 06:26:50
- OfStack
java image compression code:
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import javax.imageio.ImageIO;
public class ImageProcess {
/**
* The picture
*/
private Image img;
/**
* The width of the
*/
private int width;
/**
* highly
*/
private int height;
/**
* The file format
*/
private String imageFormat;
/**
* The constructor
* @throws Exception
*/
public ImageProcess(InputStream in,String fileName) throws Exception{
// structure Image object
img = ImageIO.read(in);
// Get the source map width
width = img.getWidth(null);
// Get the source map length
height = img.getHeight(null);
// The file format
imageFormat = fileName.substring(fileName.lastIndexOf(".")+1);
}
/**
* Compress by width or by height
* @param w int Maximum width
* @param h int Maximum height
*/
public byte[] resizeFix(int w, int h) throws IOException {
if (width / height > w / h) {
return resizeByWidth(w);
} else {
return resizeByHeight(h);
}
}
/**
* Take the width as the reference, and scale the picture equally
* @param w int The new width
*/
public byte[] resizeByWidth(int w) throws IOException {
int h = (int) (height * w / width);
return resize(w, h);
}
/**
* Take the height as the base and scale the picture equally
* @param h int New height
*/
public byte[] resizeByHeight(int h) throws IOException {
int w = (int) (width * h / height);
return resize(w, h);
}
/**
* Mandatory compressed / Enlarge image to fixed size
* @param w int The new width
* @param h int New height
*/
public byte[] resize(int w, int h) throws IOException {
// SCALE_SMOOTH Thumbnail algorithm of The smoothness of the thumbnail image is generated Priority is higher than speed The resulting images are of better quality But slowly
BufferedImage image = new BufferedImage(w, h,BufferedImage.TYPE_INT_RGB );
image.getGraphics().drawImage(img, 0, 0, w, h, null); // Draw a scaled down diagram
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ImageIO.write(image, imageFormat, baos);
return baos.toByteArray();
}
}