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我需要在 java 中创建许多不同的大型 tiff 文件，以便将其保存为数据库中的字节数组。我只设法复制旧文件，更改它并创建新文件 - 但创建文件需要太多时间（TIFFWriter.createTIFFFromImages）。我能做些什么？

public byte[] CreateTiff() throws IOException {
    try{
        File orginialFile = new File("../Dist/dist/attachment/orginialTifFile.TIF");
        if(orginialFile!=null){
            TIFFReader reader = new TIFFReader(orginialFile);
            int length = reader.countPages();
            BufferedImage[] images = new BufferedImage[length];

            for (int i = 0; i < length; i++) {
                images[i] = (BufferedImage)reader.getPage(i);
                int rgb = 0x000000; // black

                Random rand = new Random();
                int x= rand.nextInt(images[i].getHeight()/2);
                int y= rand.nextInt(images[i].getWidth()/2);

                images[i].setRGB(x, y, rgb);
            }

            File newAttachmentFile = new File("../Dist/dist/attachment/tempFile.tif");
            TIFFWriter.createTIFFFromImages(images, newAttachmentFile);
            byte[] b=  getBytesFromFile(newAttachmentFile);
            return b;
        }
    }catch(Exception e){
        System.out.println("failed to add atachment to request");
        e.printStackTrace();
        return null;
    }
    return null;
}

public static byte[] getBytesFromFile(File file) throws IOException{ InputStream is = new FileInputStream(file); // 获取文件的大小 long length = file.length();

    if (length > Integer.MAX_VALUE) {
        return null;
    }

    // Create the byte array to hold the data
    byte[] bytes = new byte[(int)length];

    // Read in the bytes
    int offset = 0;
    int numRead = 0;
    while (offset < bytes.length
           && (numRead=is.read(bytes, offset, bytes.length-offset)) >= 0) {
        offset += numRead;
    }

    // Ensure all the bytes have been read in
    if (offset < bytes.length) {
        return null;
    }

    // Close the input stream and return bytes
    is.close();
    return bytes;
}

谢谢

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1 回答 1

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您正在将数据写入文件然后从中读取，这是低效的。尽量避免这种情况。如果你必须给方法一个 File，创建一个假的 File 类，它返回一个管道、一个数组写入器或类似的东西作为它的 outputStream。

于 2010-12-05T09:37:52.120 回答