如何以无损方式从 JPEG 图像创建金字塔平铺 TIFF

Question

我需要使用无损 jpeg 操作（即在 jpegtran 中裁剪）从大型 JPEG 图像创建带有 JPEG 压缩图块的平铺金字塔 TIFF 文件。是否有任何工具或java代码来执行这样的操作？

目前我正在使用我的 Java 代码创建平铺金字塔 TIFF，但它以有损方式进行：

public static void writeTiff(RenderedOp src, File dstFile, float jpegQuality, int tileSize, int pyramid, String interpolation) throws IOException {
    dstFile.getParentFile().mkdirs();
    TIFFImageWriterSpi imageWriterSpi = new TIFFImageWriterSpi();
    TIFFImageWriter imageWriter = (TIFFImageWriter)imageWriterSpi.createWriterInstance();
    ImageOutputStream out = new FileImageOutputStream(dstFile);
    try {
        imageWriter.setOutput(out);
        imageWriter.prepareWriteSequence(null);
        BufferedImage img = null;
        for(int i=0; i<pyramid; i++) {
            img = img==null ? src.getAsBufferedImage() : JAIUtils.scale(img, 0.5F, interpolation).getAsBufferedImage();
            TIFFImageWriteParam imageWriteParam = (TIFFImageWriteParam)imageWriter.getDefaultWriteParam();
            if (tileSize>0 && (img.getWidth()>tileSize || img.getHeight()>tileSize)) {
                imageWriteParam.setTilingMode(ImageWriteParam.MODE_EXPLICIT);
                imageWriteParam.setTiling(tileSize, tileSize, 0, 0);
            }
            if (jpegQuality > 0) {
                imageWriteParam.setCompressionMode(ImageWriteParam.MODE_EXPLICIT );
                imageWriteParam.setCompressionType("JPEG");
                imageWriteParam.setCompressionQuality(jpegQuality);
            }
            imageWriter.writeToSequence(new IIOImage(img, null, null), imageWriteParam );
        }
        imageWriter.endWriteSequence();
    } finally {
        out.close();
    }
}

Answer 1

Ossim 在命令行中运行良好，但我看到它也有一个 JNI binding。