Re: [Openimaj-discuss] Serializing ByteDSIFTKeypoints

[Jonathon H. <js...@ec...>]

Try this:

ByteArrayInputStream bais = new ByteArrayInputStream(decodedBytes);

LocalFeatureList<ByteDSIFTKeypoint> decodedFeatures = MemoryLocalFeatureList.read(bais, ByteDSIFTKeypoint.class);


(obviously this will only work for lists of features & is heavily optimised for this usecase)




> On 16 Jun 2015, at 14:15, chalitha udara Perera <cha...@gm...> wrote:
> 
> Thanks for quick response Sir. It works fine for serialization. But how can i again retrieve the list of local features by deserializing the byte array ?
> 
> I tried following code, but it gives corrupted stream exception: java.io.StreamCorruptedException: invalid stream header: 4B505400
> ByteArrayInputStream bais = new ByteArrayInputStream(decodedBytes);
> 
> ObjectInputStream ois = new ObjectInputStream(bais);
> 
> LocalFeatureList<ByteDSIFTKeypoint> decodedFeatures = (LocalFeatureList<ByteDSIFTKeypoint>) ois.readObject();
> 
> Looking at OpenIMAJ api, there is a method to deserialze binaries, but how to use it to get LocalFeatureList<ByteDSIFTKeypoint> from the binary ?
> 
> 
> 
> Thanks,
> 
> Chalitha
> 
> 
> On Tue, Jun 16, 2015 at 5:59 PM, Jonathon Hare <js...@ec... <mailto:js...@ec...>> wrote:
> Do something like this (will automatically write the complete list of features without need to iterate through them):
> 
> 
> ByteArrayOutputStream baos = new ByteArrayOutputStream();
> 
> org.openimaj.io.IOUtils.writeBinary(baos, features);
> 
> byte[] bytes = baos.toByteArray();
> 
> 
> 
> 
> 
>> On 16 Jun 2015, at 11:19, chalitha udara Perera <cha...@gm... <mailto:cha...@gm...>> wrote:
>> 
>> Hi All,
>> I have extracted LocalFeaturesList<ByteDSIFTKeypoint> using Pyramid Dense Sift in OpenIMAJ. 
>> As indicated in API documentation, ByteDSIFTKeypoint implements Java Serializable interface and there fore I would like to serialize keypoints for latter use. 
>> I tried to serialize keypoints to get a byte array. But when retrieving key-points from the serialized object it loses all field values associated with it. 
>> 
>> I am using the following code for serialization
>> 
>> ByteArrayOutputStream baos = new ByteArrayOutputStream();
>> 
>> ObjectOutputStream oos = new ObjectOutputStream(baos);
>> 
>> 
>> LocalFeatureList<ByteDSIFTKeypoint> features = psift.getByteKeypoints();
>> 
>> for (ByteDSIFTKeypoint byteDSIFTKeypoint : features) {
>> 
>> 
>> oos.writeObject(byteDSIFTKeypoint);
>> 
>> 
>> byte[] bytes = baos.toByteArray();
>> 
>> }
>> 
>> 
>> 
>> Any help regarding how to correctly serialize keypoints is greatly appreciated.
>> 
>> Thanks,
>> 
>> Chalitha
>> 
>> 
>> -- 
>> J.M Chalitha Udara Perera
>> 
>> Department of Computer Science and Engineering,
>> University of Moratuwa,
>> Sri Lanka
>> ------------------------------------------------------------------------------
>> _______________________________________________
>> openimaj-discuss mailing list
>> ope...@li... <mailto:ope...@li...>
>> https://lists.sourceforge.net/lists/listinfo/openimaj-discuss <https://lists.sourceforge.net/lists/listinfo/openimaj-discuss>
> 
> 
> 
> 
> -- 
> J.M Chalitha Udara Perera
> 
> Department of Computer Science and Engineering,
> University of Moratuwa,
> Sri Lanka