提升图像处理,使用现代 API

简介

在历史上,Aspose Slides 依赖于 java.awt,并且在公共 API 中包含以下来自该库的类:

自 24.4 版本起,此公共 API 已声明为已废弃。

为了消除对这些类的依赖,我们添加了所谓的“现代 API”——即应当取代已废弃 API 使用的 API,其签名不再依赖于 BufferedImageGraphics2D 已声明为已废弃,并且其支持已从公共 Slides API 中移除。

在当前版本中,请将依赖于 java.awt 类型的公共 API 视为遗留/已废弃。对新代码以及迁移现有图像处理工作流时,请使用现代 API。

现代 API

向公共 API 添加了以下类和枚举:

请注意,IImage 是可释放的(使用后应进行释放)。

使用 getImage 渲染单个幻灯片或形状。使用 getImages 渲染多个幻灯片。使用 Images 方法加载图像,使用 addImageIImage 将图像添加到演示文稿,使用 replaceImageIImage 更新已有的演示文稿图像。

使用新 API 的典型场景如下所示:

use aspose\slides\Presentation;
use aspose\slides\ShapeType;
use aspose\slides\ImageFormat;
use aspose\slides\Images;


$pres = new Presentation();

# 实例化一个可释放的 IImage 对象,来自磁盘上的文件。
$image = Images::fromFile("image.png");

# 通过将 IImage 实例添加到演示文稿的图像集合中,创建 PowerPoint 图像。
$ppImage = $pres->getImages()->addImage($image);
$image->dispose();

# 在第 1 张幻灯片上添加图片形状
$pres->getSlides()->get_Item(0)->getShapes()->addPictureFrame(ShapeType::Rectangle, 10, 10, 100, 100, $ppImage);

$dimension = new Java("java.awt.Dimension", 1920, 1080);
# 获取表示第 1 张幻灯片的 IImage 实例。
$slideImage = $pres->getSlides()->get_Item(0)->getImage($dimension);

# 将图像保存到磁盘上。
$slideImage->save("slide1.jpeg", ImageFormat::Jpeg);
$slideImage->dispose();

$pres->dispose();

使用现代 API 替换旧代码

通常,您需要将使用 BufferedImageImageIO 的调用替换为使用 IImage 的新方法。

Legacy/deprecated API:

$dimension = new Java("java.awt.Dimension", 1920, 1080);
$slideImage = $pres->getSlides()->get_Item(0)->getThumbnail($dimension);
$imageio = new Java("javax.imageio.ImageIO");
$javafile = new Java("java.io.File", "image.png");
$imageio->write($slideImage, "PNG", $javafile);

Modern API:

$dimension = new Java("java.awt.Dimension", 1920, 1080);
$slideImage = $pres->getSlides()->get_Item(0)->getImage($dimension);
$slideImage->save("image.png", ImageFormat::Png);
$slideImage->dispose();

获取幻灯片缩略图

Legacy/deprecated API:

use aspose\slides\Presentation;


$pres = new Presentation("pres.pptx");

$slideImage = $pres->getSlides()->get_Item(0)->getThumbnail();

$imageio = new Java("javax.imageio.ImageIO");
$javafile = new Java("java.io.File", "slide1.png");
$imageio->write($slideImage, "PNG", $javafile);

$pres->dispose();

Modern API:

use aspose\slides\Presentation;
use aspose\slides\ImageFormat;


$pres = new Presentation("pres.pptx");

$slideImage = $pres->getSlides()->get_Item(0)->getImage();
$slideImage->save("slide1.png", ImageFormat::Png);
$slideImage->dispose();

$pres->dispose();

获取形状缩略图

Legacy/deprecated API:

use aspose\slides\Presentation;


$pres = new Presentation("pres.pptx");

$shapeImage = $pres->getSlides()->get_Item(0)->getShapes()->get_Item(0)->getThumbnail();

$imageio = new Java("javax.imageio.ImageIO");
$javafile = new Java("java.io.File", "shape.png");
$imageio->write($shapeImage, "PNG", $javafile);

$pres->dispose();

Modern API:

use aspose\slides\Presentation;
use aspose\slides\ImageFormat;


$pres = new Presentation("pres.pptx");

$shapeImage = $pres->getSlides()->get_Item(0)->getShapes()->get_Item(0)->getImage();
$shapeImage->save("shape.png");
$shapeImage->dispose();

$pres->dispose();

获取演示文稿缩略图

Legacy/deprecated API:

use aspose\slides\Presentation;
use aspose\slides\RenderingOptions;


$pres = new Presentation("pres.pptx");

$renderingOptions = new RenderingOptions();
$dimension = new Java("java.awt.Dimension", 1920, 1080);

$bitmaps = $pres->getThumbnails($renderingOptions, $dimension);
for ($i = 0; $i < count(java_values($bitmaps)); $i++)
{
    $thumbnail = $bitmaps[$i];
    $imageio = new Java("javax.imageio.ImageIO");
    $javafile = new Java("java.io.File", "slide" . $i . ".png");
    $imageio->write($thumbnail, "PNG", $javafile);
}

$pres->dispose();

Modern API:

use aspose\slides\Presentation;
use aspose\slides\ImageFormat;
use aspose\slides\RenderingOptions;


$pres = new Presentation("pres.pptx");

$renderingOptions = new RenderingOptions();
$dimension = new Java("java.awt.Dimension", 1920, 1080);

$images = $pres->getImages($renderingOptions, $dimension);
for ($i = 0; $i < count(java_values($images)); $i++)
{
    $thumbnail = $images[$i];
    $thumbnail->save("slide" . $i . ".png", ImageFormat::Png);
}

$pres->dispose();

向演示文稿添加图片

Legacy/deprecated API:

use aspose\slides\Presentation;
use aspose\slides\ShapeType;


$pres = new Presentation();

$imageio = new Java("javax.imageio.ImageIO");
$javafile = new Java("java.io.File", "image.png");

$bufferedImages = $imageio->read($javafile);
$ppImage = $pres->getImages()->addImage($bufferedImages);

$pres->getSlides()->get_Item(0)->getShapes()->addPictureFrame(ShapeType::Rectangle, 10, 10, 100, 100, $ppImage);

$pres->dispose();

Modern API:

use aspose\slides\Presentation;
use aspose\slides\Images;
use aspose\slides\ShapeType;


$pres = new Presentation();

$image = Images::fromFile("image.png");
$ppImage = $pres->getImages()->addImage($image);
$image->dispose();

$pres->getSlides()->get_Item(0)->getShapes()->addPictureFrame(ShapeType::Rectangle, 10, 10, 100, 100, $ppImage);

$pres->dispose();

已废弃方法及其在现代 API 中的替代方案

Presentation

方法签名 替代方法签名
public final BufferedImage[] getThumbnails(IRenderingOptions options) public final IImage[] getImages(IRenderingOptions options)
public final BufferedImage[] getThumbnails(IRenderingOptions options, float scaleX, float scaleY) public final IImage[] getImages(IRenderingOptions options, float scaleX, float scaleY)
public final BufferedImage[] getThumbnails(IRenderingOptions options, int[] slides) public final IImage[] getImages(IRenderingOptions options, int[] slides)
public final BufferedImage[] getThumbnails(IRenderingOptions options, int[] slides, float scaleX, float scaleY) public final IImage[] getImages(IRenderingOptions options, int[] slides, float scaleX, float scaleY)
public final BufferedImage[] getThumbnails(IRenderingOptions options, int[] slides, Dimension imageSize) public final IImage[] getImages(IRenderingOptions options, int[] slides, Dimension imageSize)
public final BufferedImage[] getThumbnails(IRenderingOptions options, Dimension imageSize) public final IImage[] getImages(IRenderingOptions options, Dimension imageSize)

Shape

方法签名 替代方法签名
public final BufferedImage getThumbnail() public final IImage getImage()
public final BufferedImage getThumbnail(int bounds, float scaleX, float scaleY) public final IImage getImage(int bounds, float scaleX, float scaleY)

Slide

方法签名 替代方法签名
public final BufferedImage getThumbnail() public final IImage getImage()
public final BufferedImage getThumbnail(float scaleX, float scaleY) public final IImage getImage(float scaleX, float scaleY)
public final BufferedImage getThumbnail(IRenderingOptions options) public final IImage getImage(IRenderingOptions options)
public final BufferedImage getThumbnail(IRenderingOptions options, float scaleX, float scaleY) public final IImage getImage(IRenderingOptions options)
public final BufferedImage getThumbnail(IRenderingOptions options, Dimension imageSize) public final IImage getImage(IRenderingOptions options, Dimension imageSize)
public final BufferedImage getThumbnail(ITiffOptions options) public final IImage getImage(ITiffOptions options)
public final BufferedImage getThumbnail(Dimension imageSize) public final IImage getImage(Dimension imageSize)
public final void renderToGraphics(IRenderingOptions options, Graphics2D graphics) No Modern API replacement
public final void renderToGraphics(IRenderingOptions options, Graphics2D graphics, float scaleX, float scaleY) No Modern API replacement
public final void renderToGraphics(IRenderingOptions options, Graphics2D graphics, Dimension renderingSize) No Modern API replacement

Output

方法签名 替代方法签名
public final IOutputFile add(String path, BufferedImage image) public final IOutputFile add(String path, IImage image)

ImageCollection

方法签名 替代方法签名
public final IPPImage addImage(BufferedImage image) public final IPPImage addImage(IImage image)

PPImage

方法签名 替代方法签名
public final BufferedImage getSystemImage() public final IImage getImage()

PatternFormat

方法签名 替代方法签名
public final BufferedImage getTileImage(Color styleColor) public final IImage getTile(Color styleColor)
public final BufferedImage getTileImage(Color background, Color foreground) public final IImage getTile(Color background, Color foreground)

PatternFormatEffectiveData

方法签名 替代方法签名
public final java.awt.image.BufferedImage getTileImage(Color background, Color foreground) public final IImage getTileIImage(Color background, Color foreground)

Graphics2D 的 API 支持

带有 Graphics2D 的方法已声明为已废弃,且没有直接的现代 API 替代。

请使用现代 API 的图像渲染方法,而不是渲染到 Graphics2D 的 API:

Slide

常见问题

为什么废弃了 Graphics2D

Graphics2D 的支持已在公共 API 中废弃,以统一渲染和图像的工作方式,消除对平台特定依赖的关联,并转向使用跨平台的 IImage 的方法。请使用 getImagegetImages 代替渲染到 Graphics2D

IImage 相比 BufferedImage 的实际好处是什么?

IImage 统一了对光栅图像和矢量图像的处理,并通过 ImageFormat 简化了保存为各种格式的过程。

使用现代 API 会影响生成缩略图的性能吗?

getThumbnail 切换为 getImage 并不会导致性能下降:新方法在提供相同的选项和尺寸生成图像能力的同时,仍然保留对渲染选项的支持。具体的性能提升或下降取决于使用场景,但功能上两者是等价的。