Question

我无法以jpg格式转换URI编码图像（png工作正常）。我的客户端是一个简单的jquery ajax帖子。在服务器上，我只是尝试解码图像，调整大小，并将其添加到blobstore。我正在学习JQuery，所以如果问题是在客户端，请为我愚蠢。谢谢。

客户：

function send(target){

                var sendInfo = { 
                            team: localStorage.getItem("teamName"),
                            name: target,
                            imagedata: image
                        };


                $.mobile.loading( 'show', {
                    textVisible: false,
                    theme: 'z',
                    html: ""
                });

                $.ajax({
                    type: "POST",
                    url: "/UploadImage",
                    data: sendInfo
                    }).done(function(data) {
                        $.mobile.loading('hide');
                    })
                    .fail(function(data) {
                        $.mobile.loading('hide');
                });

服务器：

public void doPost(HttpServletRequest req, HttpServletResponse res)
            throws IOException {
        try {

        String team = req.getParameter("team");
        String name = req.getParameter("name");
        String imageData = req.getParameter("imagedata").replaceAll("data:image/[a-z]*;base64,", "");
        System.err.print("ImageData: " + imageData);

        Image image = ImagesServiceFactory.makeImage(Base64Utils.fromBase64(imageData));
        System.out.println(image.getHeight() + " : " + image.getWidth());

        } catch (Exception e) {
            e.printStackTrace();
        }
}

测试案例：

ImageData(JPEG): data:image/jpeg;base64,/9j/4AAQSkZJRgABAQAAAQABAAD/4QBYRXhpZgAATU0AKgAAAA...
RETURNS: java.lang.IllegalArgumentException: imageData must be a valid image
ImageData(PNG): data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAABQAAAALQCAIAAABAH0oBAAAAA3NCS...
RETURNS: 720 : 1280 (i.e. it's working)

Answer 1

此work around适用于开发，但不适用于生产。 sun.misc.BASE64Decoder（）受限制。

String base64encJPG = (String)req.getParameter("imagedata").replaceAll("data:image/[a-z]*;base64,", "");  
        byte decoded[] = new sun.misc.BASE64Decoder().decodeBuffer(base64encJPG);  
        InputStream in = new ByteArrayInputStream(decoded);  
        BufferedImage bufferedImage = ImageIO.read(in);  
        System.out.println(bufferedImage.getHeight() + " : " + bufferedImage.getWidth());

Answer 2

如果你正在使用appengine，你可以使用apache commons library

public byte[] decode(final byte[] bytes) {
    return org.apache.commons.codec.binary.Base64.decodeBase64(bytes);
}

无法在GWT中转换Base64 jpg

2 个答案: