Now a days use of Camera phones are becoming increasingly pervasive. These cameras, designed primarily for taking pictures, are being used as ubiquitous input devices which acquire information from the physical world e.g. to translate documents, signs or to perform image based search. So far one of the most successful applications is to use camera phones to scan 2D barcodes printed on products, papers, advertisements and business cards.
In this paper, we describe a data transfer scheme that uses the camera in a smart phone as an alternative data channel. Here the data is encoded as a sequence of 2-D barcode images, then this 2-D barcode image displayed on a flat panel display, after that that 2-D barcode is captured by the camera, and decoded by the software installed in mobile. The decoded data is written to a file.
This method depends on visual communication and does not require special hardware. Users only need to point the camera at a monitor displaying the VCode to download.
We have implemented a prototype which allows users to download various types of files successfully, including pictures, and small size text file onto camera phones running Symbian and Windows Mobile platforms
Keywords: Image processing, Mobile Vision and Recognition
Barcodes are used to encode data as input for computer system. These barcodes encode alpha-numeric, keyboard, or binary information in a machine-readable format.
In our proposed system , we describe a data transfer scheme in that camera in mobile phone use as data channel .First of all data is encoded as sequence of 2-D barcode. After that encoded data is displayed on computer screen and then that image is captures by preinstalled software in mobile device. In last step mobile software decode the encoded data and save original data in file in mobile memory. For that user only need to captures the encoded data in camera phone by taking pictures or by taking as Video. And that is the Video Barcode technology, Vcode.
Basically there are three types of barcode,1-D and 2-D and 3D .Here we use 2-D barcode for encoding and Decoding data. And in 2-D barcode we use QRCode for data presentation. There are many 2D barcode tagging systems available online among them are: Semacode URL tagging system , ShotCode , QR code , and BeeTagg , to name but a few. As shown in figure 1. The "QR" is derived from "Quick Response", as the creator intended the code to allow its contents to be decoded at high speed.
Figure 1 Example of QRCode.
II OVERVIEW OF QR CODES
Figure 2 Use of QR code by Mobile Phones
III SCOPE OF SYSTEM
Development of an Encoder so that any data stream can be encoded as a VCode.
Development of display components so that a VCode can be displayed in flat panel displays.
Development of components for acquisition and processing of VCode images, including a user interface, acquisition and image-enhancement components. These will include VCode detection, normalization, perspective correction to facilitate recognition and decoding.
Decoding the captured VCode frame by frame and reconstruct the data encoded.
Integrating all of the algorithms onto the mobile device. We designed a preliminary user interface, developed integrated software on mobile devices, and optimized code for best resource utilization.
IV SYSTEM ARCHITECURE AND IMPLEMENTATION
Original file on Mobile Device
Figure 3 Block diagram of System
This Module accepts original file from computer side. To encode a data file into a VCode, we first split the data file into small segments, and then encode each segment into an image sequence. As the cameras on phones often have much lower quality than digital cameras, and we expect users to capture VCode in real environment without constraints in lighting and perspective angles. Our strategy is to use error control in both time and space to make code more robust against these types of degradations. We use data Partitioning and Error Correction.
2.Vcode Rendering This module converts each frame (including error correction frames) into an image, which can be displayed on flat screens Since the sensors in camera phones are often not square, our design for the frame of a VCode is a rectangle to have a similar aspect ratio to the captured image. The data area consists of black and white cells, each carrying one bit of data with black representing 1 and white representing 0.
3.Vcode Acquisition The acquisition size and frame rate are constrained by the device. The process, however, must optimize throughput by trading off acquisition speed, image resolution, and processing requirements.. The acquisition process itself is very simple: Users only need to aim the camera at the VCode to keep the frames at the center of the display. Detection and decoding will occur at frame rate.
4.Image IPROCESSING Before decoding, each captured frame needs to be perceptively corrected, enhanced, and converted into binary. The algorithm must be very efficient to meet the real-time requirement. We have identified the following challenges when processing the detected image. We have identified the following challenges when processing the detected image. 1.Perspective distortion 2 Uneven lighting 3. Detection and localization
5.BinarizationFor a "VCode" matrix we sample coordinates on the image and read their gray scale values. Then we convert these gray scale values into binary 0 or 1
6.Vcode Decoder After a binary matrix is fed to the decoder, the sequence is verified as follows.
1.The frame header is double checked with the checksum. If this frame has not been correctly decoded, it is decoded and inserted to a slot uniquely assigned to each frame.
2. After insertion, the data chunk containing the frame is expanded by one frame. Since we use a -Reed-Solomon code to encode the chunk over frames, theoretically we can decode the chunk .Therefore, after a chunk has accepted frames, decoding starts.
3. If decoding succeeds, no additional data needs to be added,if it fails, we continue to add frames until decoding is successful.
4.When all chunks are completed for decoding, the decoder reassembles the stream to generate a file stored to file system on devices.
Figure 4 Decoding flow chart
V. Results AND DISCUSSIONs
Figure 5 File Input Form.
Figure 6 Segment Creation status
Figure 7 VCode Encoded Form
Figure 8 Form showing File Encoded as VCode
Figure 9 Example of VCoded Frame
VI. FEATURES AND APPLICATIONS
1. The software relies on visual communication and does not require special hardware or data plans.
2. The significance of this software is that it is possible for content to be reliably transferred through camera anytime and anywhere.
3. Visual communication of this software does not require any cable or wireless connection.
In Japan QR codes are found on everything from business cards to fresh lettuce. Now they are coming to the West and advertising and promotion will never be the same again. 2D Code will keep you informed as it happens, with news, views and analysis.1. The Scan Life mobile application uses the camera phone to read all major 1D and 2D barcode formats including Data matrix, EZcode, QR, UPC, and EAN. The application scans a code to immediately launch a specific action like displaying a website, loading a video, dialing a phone number and more. This makes all physical objects interactive and removes the need for a user to type long URL's or search for information using keywords 2. QR codes have become a major tool to facilitate the usage of mobile data services, and QR codes help to overcome one of the most important barriers to mobile commerce and Mobile content sales
3. Initially developed for logistics and car parts supply chain management by Denso Corporation, applications for QR codes have recently found explosive growth with the advent of camera phones. QR codes are a very important information input and output tool and are facilitating the growth of the mobile economy.
VII FUTURE SCOPE
This paper is must-read for mobile communication professionals globally, who need to be in touch with the state-of-the-art of mobile phone design, mobile phone applications for commerce and content sale, mobile marketing, and advertising targeting mobile users.
1. The major contribution of this system is that it provides a new method to enable camera phones to download data when other communication channels are inappropriate.
2. The download speed, however, is not fast enough compared with existing wireless or cable connections. This limitation will be significantly improved when the camera resolutions become higher and the processing speed increases.
3. Another promising method to increase bit rate is to use color instead of black and white cells so each cell can carry more bits. If eight colors are used, for example, the speed can be tripled theoretically.
Here we describe a visual communication technique in which data is transferred from PC to mobile without any wire or wireless connection .Data is in the form of a text file or small size image .Due to constraint of mobile camera resolution data is not transmitted fast. But it is a novel technique which does not require any extra hardware or data plans for transmission. As here demonstrated that cameras can be used for pervasive data transfer to mobile phones. In this system encoding and decoding algorithms including data splitting, error correction coding, image capture, correction of perspective distortion are explained in detail The major contribution of this system is that it provides a new method to enable camera phones to download data when other communication channels are inappropriate. The download speed, however, is not fast enough compared with existing wireless or cable connections. This limitation will be significantly improved when the camera resolutions become higher and the processing speed increases.
 Xu Liu, David Doermann, Huiping Li." VCode-Pervasive Data Transfer Using Video Barcode", in Proc. "IEEE conference on Multimedia ," Volume 10, April 4 2008, pp. 361-371.
 Y. Ijiri, M. Sakuragi, and S. Lao, "Security management for mobile devices by face recognition," in Proc. 7th Int. Conf. Mobile Data Management (MDM'06)., Washington, DC, 2006, pp. 49-49
 X. Chen, J. Yang, J. Zhang, and A. Waibel, "Automatic detection of signs with affine transformation," in Proc. 6th IEEE Workshop on Applications of Computer Vision., Washington, DC, 2002, pp. 32-32.
 "A pda-based sign translator," in Proc. 4th IEEE Int. Conf. Multimodal Interfaces., Washington, DC, 2002, pp. 217-217.
 K. S. Bae, K. K. Kim, Y. G. Chung, and W. P. Yu, "Character recognition system for cellular phone with camera," in Proc. 29th Annu. Int. Computer Software and Applications Conf. (COMPSAC'05) Volume 1., Washington, DC, 2005, pp. 539-544.
 M. Koga, R. Mine, T. Kameyama, T. Takahashi, M. Yamazaki, and T. Yamaguchi, "Camera-based Kanji OCR for mobile-phones: Practical issues," in Proc. 8th Int. Conf. Document Analysis and Recognition., Washington, DC, 2005, pp. 635-639.
 E. Ohbuchi, H. Hanaizumi, and L. Hock, "Barcode readers using the camera device in mobile phones," in Proc. 2004 Int. Conf. Cyberworlds, 2004, pp. 260-265.
 H. Hee, II and J. J. Koo, "Implementation of algorithm to decode two-dimensional barcode pdf-417," in Proc. 6th Int. Conf. Signal Processing, 2002, vol. 2, pp. 1791-1794.
Online Link References
 Introduction to QR Code - http://en.wikipedia.org/wiki/QR_Code
 For error correction technique of Reed-Solomon - http:// wikipedia.org/reed-solomon.com
 QR Code Version Information - http://QRcode_com.htm