哪位大神能给一个java的快速高效的图片缩放的功能
我自己也写了一个方法,但是速度不是很快,而且批量操作的时候耗时太长。求做过的大神们给个提示
public static BufferedImage createThumbnail(BufferedImage image, int size, String type) {
BufferedImage thumbnail = null;
if(image == null) {
System.out.println("文件不存在");
return thumbnail;
}
if(size <= 0) {
return thumbnail;
}
Image srcUpload = null;
try {
srcUpload = (Image)image;
int newWidth = 0, newHight = 0;
int w = srcUpload.getWidth(null);
int h = srcUpload.getHeight(null);
if("width".equals(type)) {
newWidth = size;
newHight = (int) (h * size / w);
}
else if("hight".equals(type)) {
newHight = size;
newWidth = (int) (w * size / h);
}
thumbnail = new BufferedImage(newWidth, newHight, BufferedImage.TYPE_3BYTE_BGR);
thumbnail.getGraphics().drawImage(srcUpload.getScaledInstance(newWidth, newHight, Image.SCALE_SMOOTH), 0, 0, null);
}
catch(Exception e) {
e.printStackTrace();
}
return thumbnail;
} 图片缩放?图片?缩放??java图片缩放
[解决办法]
www.jmagick.org/? 这个不错,速度和效果都挺好,缺点是要安装imagemagick.
[解决办法]
/**
* Resize an image
* @param originalImage The image file
* @param to The destination file
* @param w The new width (or -1 to proportionally resize)
* @param h The new height (or -1 to proportionally resize)
*/
public static void resize(File originalImage, File to, Integer w, Integer h) {
try {
BufferedImage source = ImageIO.read(originalImage);
int owidth = source.getWidth();
int oheight = source.getHeight();
double ratio = (double) owidth / oheight;
if (w < 0 && h < 0) {
w = owidth;
h = oheight;
}
if (w < 0 && h > 0) {
w = (int) (h * ratio);
}
if (w > 0 && h < 0) {
h = (int) (w / ratio);
}
String mimeType = "image/jpeg";
if (to.getName().endsWith(".png")) {
mimeType = "image/png";
}
if (to.getName().endsWith(".gif")) {
mimeType = "image/gif";
}
// out
BufferedImage dest = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Image srcSized = source.getScaledInstance(w, h, Image.SCALE_SMOOTH);
Graphics graphics = dest.getGraphics();
graphics.setColor(Color.WHITE);
graphics.fillRect(0, 0, w, h);
graphics.drawImage(srcSized, 0, 0, null);
ImageWriter writer = ImageIO.getImageWritersByMIMEType(mimeType).next();
ImageWriteParam params = writer.getDefaultWriteParam();
FileImageOutputStream toFs = new FileImageOutputStream(to);
writer.setOutput(toFs);
IIOImage image = new IIOImage(dest, null, null);
writer.write(null, image, params);
toFs.flush();
toFs.close();
} catch (Exception e) {
throw new RuntimeException(e);
}
}