Java 如何从 InputStream 创建图像、调整大小并保存？
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How to create an image from an InputStream, resize it and save it?
提问by Kaz Miller
I have this code where i get an InputStreamand create an image:
我有这个代码，我在那里得到一个InputStream并创建一个图像：
Part file;
// more code
try {
InputStream is = file.getInputStream();
File f = new File("C:\ImagenesAlmacen\QR\olaKeAse.jpg");
OutputStream os = new FileOutputStream(f);
byte[] buf = new byte[1024];
int len;
while ((len = is.read(buf)) > 0) {
os.write(buf, 0, len);
}
os.close();
is.close();
} catch (IOException e) {
System.out.println("Error");
}
The problem is that I have to resize that image before i create if from the InputStream
问题是我必须在创建之前调整该图像的大小，如果从 InputStream
So how to resize what I get from the InputStreamand then create that resized image. I want to set the largest side of the image to 180px and resize the other side with that proportion.
那么如何调整我从中获得的内容的InputStream大小，然后创建调整大小的图像。我想将图像的最大边设置为 180 像素，并以该比例调整另一边的大小。
Example:
例子：
Image = 289px * 206pxResized image = 180px* 128px
图像 =289px * 206px调整大小的图像 = 180像素* 128px
采纳答案by Kaz Miller
I did this:
我这样做了：
try {
InputStream is = file.getInputStream();
Image image = ImageIO.read(is);
BufferedImage bi = this.createResizedCopy(image, 180, 180, true);
ImageIO.write(bi, "jpg", new File("C:\ImagenesAlmacen\QR\olaKeAse.jpg"));
} catch (IOException e) {
System.out.println("Error");
}
BufferedImage createResizedCopy(Image originalImage, int scaledWidth, int scaledHeight, boolean preserveAlpha) {
int imageType = preserveAlpha ? BufferedImage.TYPE_INT_RGB : BufferedImage.TYPE_INT_ARGB;
BufferedImage scaledBI = new BufferedImage(scaledWidth, scaledHeight, imageType);
Graphics2D g = scaledBI.createGraphics();
if (preserveAlpha) {
g.setComposite(AlphaComposite.Src);
}
g.drawImage(originalImage, 0, 0, scaledWidth, scaledHeight, null);
g.dispose();
return scaledBI;
}
And I did not use the other code.
而且我没有使用其他代码。
Hope helps someone!
希望对某人有所帮助！
