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多分辨率图像 API
Java 9 定义多分辨率图像 API,开发者可以很容易的操作和展示不同分辨率的图像了。
以下是多分辨率图像的主要操作方法:
- Image getResolutionVariant(double destImageWidth, double destImageHeight) − 获取特定分辨率的图像变体 - 表示一张已知分辨率单位为 DPI 的特定尺寸大小的逻辑图像,并且这张图像是最佳的变体。。
- List<u> getResolutionVariants() − 返回可读的分辨率的图像变体列表。
- List<image> getResolutionVariants() − 返回可读的分辨率的图像变体列表
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://static.nowcoder.com/images/res/logo/logo-v3.png", | |
"https://uploadfiles.nowcoder.com/app/android/app.png", | |
"https://static.nowcoder.com/images/wx-rcode.jpg"); | |
List<Image> images = new ArrayList<Image>(); | |
for (String url : imgUrls) {images.add(ImageIO.read(new URL(url))); | |
} | |
// 读取所有图片 | |
MultiResolutionImage multiResolutionImage = | |
new BaseMultiResolutionImage(images.toArray(new Image[0])); | |
// 获取图片的所有分辨率 | |
List<Image> variants = multiResolutionImage.getResolutionVariants(); | |
System.out.println("Total number of images:" + variants.size()); | |
for (Image img : variants) {System.out.println(img); | |
} | |
// 根据不同尺寸获取对应的图像分辨率 | |
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)); | |
} | |
} |
正文完
发表至: javascript
2019-09-21