Tuesday, December 31, 2013

2014 New Year Fireworks in Vienna, Austria

Happy new year !!
Here are some videos and photos of new year ceremony with fireworks in Vienna, Austria. 











Tuesday, December 24, 2013

Extended Tracking in Qualcomm Vuforia SDK 2.8

Qualcomm Vuforia SDK 2.8 provides a new feature called ‘Extended Tracking’, which allows a user to move the phone’s camera with more freedom. The feature looks similar to Qualcomm’s one of demos in Uplinq 2013. 

Conventional augmented realty Apps requires the phone camera to see the target object where virtual contents are overlaid. Thus, the virtual objects should be designed to be smaller than a certain volume of a space around the target object. 

Vuforia’s Extended Tracking can not only keep tracking although a target is out of the phone camera’s view, but also allows a user to move far away from a target and interact with virtual contents. 

Here are two example videos showing what Extended Tracking feature provide.







 In Vuforia SDK 2.8, there is a new sample App named VuforiaSamples, which is written in JAVA API instead of C++ JNI interface. The sample is an all-in-one solution that contains all the samples provided separately.



Extended tracking is turned off by default and 
can be enabled in the menu



If Extended Tracking is turned on, buildings are overlaid on the target 
instead of a teapot. You may not see the top of the tall building 
with previous tracking methods in Vuforia SDK



Extended tracking allows to look upward and tracking is kept well


Tracking is still good while the Chips target is out of the camera's view


Overall, Extended Tracking is one of computer vision technologies to improve the level of current augmented reality Apps although current extended tracking is not perfect. Tracking sometimes has jitters during in the extended tracking mode. I hope it will help developers to extend their idea for better augmented reality Apps on mobile devices 

Friday, January 18, 2013

Using Preview to insert a signature to a PDF on Mac OSX


If you have experience on publishing research papers, you may know about submitting a agreement on copyright to a publisher. Usually, you need to print a copyright form out, write your signature, make a photocopy of it, and finally send a PDF of TIFF to the publisher by e-mail or upload it to a publisher's web. However, it's quite annoying procedure and the quality of a scanned copy of the form is not good. Moreover, you need a printer machine and a scanner to do this. On the other hand, we do not send the printed one to the publisher in these days and thus it's a waste of a paper because it is just used for create a photocopy.  

If you are a MAC user, there is a simple and elegant way to do it without any additional hardware, i.e., printers and scanners. 

The 'Preview' application, which is a default application for viewing images and PDFs on MAC OS X, provides a function that allows you to insert your signature in a PDF file. 

You can see how it works from: Help->Search. 
Type 'signature' and you'll see appropriate menus and help items. 



 Click Annotation tool button, highlighted in blue as you can see below. 




If you click the inverted triangle , you will see a sub-menu, saying 'Create Signature from...'. Just select it. 



Then, you'll see a video stream captured from your machine's FaceTime camera. 
Following the guideline in right, first write your signature on a white paper. Avoid using a pen with a very thin tip. If lines of your signature are too thin, signature detection will fail. 



Then, put your signature in front of the camera. Make some overlap between your signature and the blue line on a screen. The machine detects your signature automatically and shows it as below. If the detected signature is good enough, press Accept. Your signature is saved to the Preview app. 




To add the created signature to a PDF, select appropriate signature from the sub-menu of the signature tool and put the mouse cursor (it becomes cross) on a right location of the PDF.  



If there is a line, you'll see a blue guideline. If you click at the location, your signature will be inserted there. 


Here is a screenshot of inserted signatures !!