2 
ImagesService imagesService = ImagesServiceFactory.getImagesService();
BlobKey bk = currentProfile.getProfileBlobKey();
Image oldImage = ImagesServiceFactory.makeImageFromBlob(bk);
Transform resize = ImagesServiceFactory.makeResize(500, 500);
Image newImage = imagesService.applyTransform(resize, oldImage);
int imageWidth = newImage.getWidth();
int imageHeight = newImage.getHeight();

This code doesn't seem to work since ImagesServiceFactory.makeImageFromBlob(bk); doesn't return a real Image. Does anyone know a workaround for this? This seems to be the expected behavior. This issue is discussed here but they don't have a solution for getting the height and width just the byte[]

4

2 回答 2

2

尝试这个：

FileService fileService = FileServiceFactory.getFileService();
AppEngineFile blobFile = fileService.getBlobFile(blobKey);
FileReadChannel readChannel = fileService.openReadChannel(blobFile, false);
byte[] imageData = getBytes(Channels.newInputStream(readChannel));
Image oldImage = ImagesServiceFactory.makeImage(imageData);
// now you have the real Image

还有这个用于读取输入流的小片段：

public static byte[] getBytes(InputStream is) throws IOException {
    ByteArrayOutputStream buffer = new ByteArrayOutputStream();

    int len;
    byte[] data = new byte[10000];
    while ((len = is.read(data, 0, data.length)) != -1) {
        buffer.write(data, 0, len);
    }

    buffer.flush();
    return buffer.toByteArray();
}
于 2013-01-24T23:30:14.617 回答
0

你试过 ImageReader 类吗？

于 2013-01-24T20:53:09.603 回答