将映像存储在Hbase中，丢失元数据和Exif

Question

Uploading an image to hbase using Java program, after retrieving the image I found there is difference in file size eventually increased and most of Exif and Meta data loss (GPS location data, camera details, etc..)

Code :

public ArrayList<Object> uploadImagesToHbase(MultipartFile uploadedFileRef){
    byte[] bytes =uploadedFileRef.getBytes();
    ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
    ImageIO.write(image, "jpg", outputStream);
    HBaseAdmin admin = new HBaseAdmin(configuration);
    HTable table = new HTable(configuration, "sample");
    Put image = new Put(Bytes.toBytes("1"));
    image.add(Bytes.toBytes("DataColumn"), Bytes.toBytes(DataQualifier), bytes);
    table.put(image);

How to store and retrieve a Image with out any change / loss?

Answer 1

Please try using SerializationUtils from Apache Commons Lang.

Below are methods

static Object   clone(Serializable object)  //Deep clone an Object using serialization.
static Object   deserialize(byte[] objectData) //Deserializes a single Object from an array of bytes.
static Object   deserialize(InputStream inputStream)  //Deserializes an Object from the specified stream.
static byte[]   serialize(Serializable obj) //Serializes an Object to a byte array for storage/serialization.
static void serialize(Serializable obj, OutputStream outputStream) //Serializes an Object to the specified stream.

While storing in to hbase you can store byte[] which was returned from serialize. While getting the Object you can type cast to corresponding object for ex: File object and can get it back.

Answer 2

Most likely you are just over-complicating things. :-)

The reason why you are losing the Exif and other metadata, is that the ImageIO convenience methods ImageIO.read(...) and ImageIO.write(...) does not preserve metadata. The good news is, they are not needed.

As you seem to already have the image data from the MultipartFile , you should simply store that data (the byte array) in the database, and you will store exactly what the user uploaded. No difference in file size, and metadata will be untouched.

Your code above doesn't compile for me, and I'm no HBase expert, so I just leave that out (as you have already been able to store an image, to see the size/quality difference and metadata loss, I assume you know how to do that :-) ). But here's the basics:

public ArrayList<Object> uploadImagesToHbase(MultipartFile uploadedFileRef) {
    byte[] bytes = uploadedFileRef.getBytes();

    // Store the above "bytes" byte array in HBase *as is* (no ImageIO)
}