Java 9 - 多分辨率图像API( Multiresolution Image API)
使用Java 9，引入了一种新的多分辨率图像API，它支持具有不同分辨率变体的多个图像。 此API允许将具有不同分辨率的一组图像用作单个多分辨率图像。 以下是多分辨率图像的主要操作。
Image getResolutionVariant(double destImageWidth, double destImageHeight) - 获取特定图像，该图像是表示指定大小的逻辑图像的最佳变体。
List《Image》 getResolutionVariants() - 获取所有分辨率变体的可读列表。
例子 (Example)
import java.io.IOException;
import java.net.URL;
import java.net.MalformedURLException;
import java.util.ArrayList;
import java.util.List;
import java.awt.Image;
import java.awt.image.MultiResolutionImage;
import java.awt.image.BaseMultiResolutionImage;
import javax.imageio.ImageIO;
public class Tester {
public static void main(String[] args) throws IOException, MalformedURLException {
List<String> imgUrls = List.of("http://www.iowiki.com/java9/images/logo.png",
"http://www.iowiki.com/java9/images/mini_logo.png",
"http://www.iowiki.com/java9/images/large_logo.png");
List<Image> images = new ArrayList<Image>();
for (String url : imgUrls) {
images.add(ImageIO.read(new URL(url)));
}
// read all images into one multiresolution image
MultiResolutionImage multiResolutionImage =
new BaseMultiResolutionImage(images.toArray(new Image[0]));
// get all variants of images
List<Image> variants = multiResolutionImage.getResolutionVariants();
System.out.println("Total number of images: " + variants.size());
for (Image img : variants) {
System.out.println(img);
}
// get a resolution-specific image variant for each indicated size
Image variant1 = multiResolutionImage.getResolutionVariant(156, 45);
System.out.printf("\nImage for destination[%d,%d]: [%d,%d]",
156, 45, variant1.getWidth(null), variant1.getHeight(null));
Image variant2 = multiResolutionImage.getResolutionVariant(311, 89);
System.out.printf("\nImage for destination[%d,%d]: [%d,%d]", 311, 89,
variant2.getWidth(null), variant2.getHeight(null));
Image variant3 = multiResolutionImage.getResolutionVariant(622, 178);
System.out.printf("\nImage for destination[%d,%d]: [%d,%d]", 622, 178,
variant3.getWidth(null), variant3.getHeight(null));
Image variant4 = multiResolutionImage.getResolutionVariant(300, 300);
System.out.printf("\nImage for destination[%d,%d]: [%d,%d]", 300, 300,
variant4.getWidth(null), variant4.getHeight(null));
}
}
输出 (Output)
Total number of images: 3
BufferedImage@7ce6a65d: type = 6 ColorModel: #pixelBits = 32 numComponents = 4
color space =java.awt.color.ICC_ColorSpace@548ad73b transparency = 3
has alpha = true isAlphaPre = false ByteInterleavedRaster: width =311
height = 89 #numDataElements 4 dataOff[0] = 3
BufferedImage@4c762604: type = 6 ColorModel: #pixelBits = 32 numComponents = 4
color space =java.awt.color.ICC_ColorSpace@548ad73b transparency = 3
has alpha = true isAlphaPre = false ByteInterleavedRaster: width =156
height = 45 #numDataElements 4 dataOff[0] = 3
BufferedImage@2641e737: type = 6 ColorModel: #pixelBits = 32 numComponents = 4
color space =java.awt.color.ICC_ColorSpace@548ad73b transparency = 3
has alpha = true isAlphaPre = false ByteInterleavedRaster: width =622
height = 178 #numDataElements 4 dataOff[0] = 3
Image for destination[156,45]: [311,89]
Image for destination[311,89]: [311,89]
Image for destination[622,178]: [622,178]
Image for destination[300,300]: [622,178]
