CyberOffice: A Smart Mobile Application for Instant Meetings

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1 , pp CyberOffice: A Smart Mobile Application for Instant Meetings Dong Kwan Kim 1 and Jae Yoon Jung 2 1 Department of Computer Engineering, Mokpo National Maritime University Jeonnam, , Korea 2 Department of Multimedia Engineering, Catholic University of Pusan Pusan, , Korea 1 dongkwan@mmu.ac.kr, 2 abcd4412@gmail.com Abstract Even though web-based conferencing applications enable the user to overcome spatial constraints, they require additional presentation facilities such as beam projectors, computers, and video presentation aids. Most of all, Internet connection is an essential element to connect the participants. Such a Web conferencing may be well suited for formal meetings or presentations rather than small-scale group meetings. To improve the promptness and availability, meeting applications for small-scale group meetings should mitigate communication constraints and reduce initial setup time. In this paper, we present the design and implementation of a smart meeting Android application called CyberOffice which is based on Wi-Fi Direct. Our application enables a presenter to start meetings quickly anywhere at any time without Internet connection. In addition, there is no need for necessary devices except an Android smartphone to join a meeting. The proposed application indicates that the Wi-Fi Direct APIs of the Android platform can be effectively applied for file sharing and event exchanges. Keywords: Smart Meeting Application, Wi-Fi Direct, Android Platform, Real-time Synchronization 1. Introduction The rapid proliferation of mobile devices leads to the development of various mobile applications ranging from entertainment, education, health to business. According to the prediction of Gartner, mobile phones will overtake PCs as the most common Web access device worldwide by 2013 [1]. In addition, the worldwide application stores accelerate the distribution of mobile applications by encouraging software developers to upload their products. In particular, we can find that there is a variety of business applications at Google Play [2] and these applications provide meeting support and schedule management. Among them, we focus on mobile apps for presentations or meetings. Most of Web conferencing products are based on a client/server environment--a presentation file places on a server and a mobile phone is used to control the screen of the shared file at a near distance. While a personal computer as server stores a presentation file and runs a meeting application, a mobile device as client is used to simply browse or remotely control the presentation file on a server. Even though Web conferencing applications have been utilized for daily meetings, they may not be well suited for small-scale group meetings which frequently take place outdoors or at meeting rooms equipped without presentation facilities such as beam projectors, video presentation aids, and Internet connection. For instant and quick meetings, mobile devices can ISSN: IJSEIA Copyright c 2014 SERSC

2 be utilized to minimize complicated and time-consuming configuration installation. Furthermore, such an application needs to offer easy-to-use interfaces and communication capabilities without Internet connection. To this end, we propose an online meeting application called CyberOffice for the smallscale group meetings or business presentations. Our application is based on Wi-Fi Direct [3, 4] which makes it possible to conduct meetings without Internet connection. Wi-Fi Direct is a communication standard that allows Wi-Fi devices to connect to each other without the need for a wireless access point or Internet connection. Therefore, with Wi-Fi Direct, informal meetings or presentations can take place anywhere at any time on campus, outdoor places, etc. The proposed smart meeting application enables presenters to start meetings using mobile phones to invite participants. In addition, it provides screen-sharing functionality which allows presenters to share their screen with their participants during presentations. The rest of this paper is structured as follows. Section 2 briefly summarizes existing online meeting applications. Sections 3 and 4 describe design consideration and implementation issues of our smart meeting application. Section 5 presents concluding remarks and future work. 2. Related Work In most mobile applications for meetings, a mobile device looks like a simple browser or a remote controller namely, a mobile device as client can simply browse or remotely control a presentation file on a server. In contrast, our application supports peer-to-peer communication among mobile devices without any server. Our application is installed on mobile devices directly connected through Wi-Fi Direct and each participated mobile device has a presentation file locally. Furthermore, one technical advantage of our meeting application is that it can control the screen of the client by using real-time page synchronization [5]. The typical architecture of the meeting application is based on the Internet network and a smartphone can remotely move a page of a presentation file on a server during a meeting. The smartphone connects the server through its IP address and port number. They support socket communication and allow for simply changing page numbers. Some applications focus on viewing meeting documents by supporting popular document formats such as Microsoft PowerPoint, Excel, and Word. In general, these applications do not allow the user to edit the document which places on a local storage. AllShare Play by Samsung allows for sharing digital contents among devices including TVs, PCs, Tablets, and mobile phones. It is based on the local network and is implemented by extending file sharing with remote machines. Since this service is not open but proprietary, all the devices need to be registered to get an individual account number. Therefore, the contents sharing service is not supported between Samsung digital products and others. The AllShare Play functionality of Galaxy S III is similar to our method in that mobile devices can share simple comments as well as files. However, our smart meeting application supports device independence namely, it can run on a variety of mobile devices in which the Android platform 4.0 or later is installed. 44 Copyright c 2014 SERSC

3 3. Design of Smart Meeting Application Figure 1. Managing Meeting Groups-making Groups, Getting IP Addresses and Transferring Presentation Files among Participants Figure 1 illustrates three main steps for managing meeting groups--building meeting groups, getting IP addresses from meeting all the participants and transferring presentation files among participants. When the meeting application starts, a group owner (i.e., a presenter) can create a meeting group where meeting participants will join. The group owner waits for join requests from participants. When a participant device enters into the range of the Wi-Fi Direct host (i.e., a group owner), it can be connected with a group owner by the existing ad-hoc protocol. After the connection between them has been established using the Wi- Fi Direct, the participant can ask the group owner to join the meeting group. Once the participant has joined the group, he or she sends an IP address the group owner. For unicast communication, the group owner stores the IP address to an Arraylist. The group owner uses the IP addresses to manage synchronization issues between group owner and participant. The participants wait for a meeting file in PDF format via socket connection. By selecting a meeting file, the group owner can distribute it to the all the waiting participants. The main feature of our application is to control remotely the screen of the participant s mobile device. As shown in Figure 2, the group owner and participants share the same page of the presentation file by using the real-time remote control. To change the page number, the group owner scrolls up and down the screen or pushes the volume key. Whenever the page number changes, a current page number is sent to all the participants via socket connection. As soon as a new page number arrives, the page of the presentation file at the participant side goes to the new one. All participants in the meeting group share the same page as that of the group owner. The participant can also move the page of the presentation PDF file. However, the new page number is not sent to the group owner and the other group members. The remote control of the group owner includes page moving, screen rotation, zoom-in, zoom-out, and comments. To use zoom-in and zoom-out, the group owner enlarges or minimizes the specific area of the presentation file. Such events are sent to the all group members and their screens are synchronized with that of the group owner. Copyright c 2014 SERSC 45

4 The group members can share questions or comments on the presentation file. The participant can ask for authorization to question and then the group owner allows or rejects the request. When the group owner accepts the request of the participant, the participant can give a question. The group owner answers to the question of the participant. The questions and answers are shared with the other group members. Figure 2. Synchronizing the Current Page and Notes among Participants Our smart meeting application needs to use relatively frequent data transmission for page and note synchronization during the meeting. For the better performance, the application extends AsyncTask which is an abstract class and allows to perform background operations and publish results on the UI thread. Using AsyncTask enables the participant to receive and process necessary data depending on the situation in an efficient way. The common data set includes page numbers, notes, and IP addresses. Threads are used to receive data in the general mobile programming model a separate and dedicated thread is created and is ready to handle data. The disadvantage of using a thread is that the application should deal with the UI access of the meeting application in a separate way. To use AsyncTask makes it possible to manage thread resources conveniently and improve UI accessibility. Table 1. Extending the AsyncTask Class public class MyAsyncTask extends AsyncTask<Void, Integer, Integer>{ public Integer doinbackground(void... params) { serversocket = new ServerSocket(PORT); Socket client = serversocket.accept(); BufferedReader in = new BufferedReader( new InputStreamReader(client.getInputStream())); String tmp = in.readline(); return data; } public void onpostexecute(integer result){ if (FLAG == PAGE){ Page_AsyncTask_execute(); }else if (FLAG == NOTE) { Note_AsyncTask_execute(); } } } 46 Copyright c 2014 SERSC

5 Table 1 shows class MyAsyncTask extends AsyncTask and overrides the necessary methods including doinbackground and onpostexecute. When MyAsyncTask starts, the doinbackground method deals with data transmission and waits a socket from a client. The method processes the received data and then passes a return value to the UI thread for the next processing. The onpostexecute method visually represents the received return value on the UI screen. If a page number is received, the screen switches to the received page number. If note data is transmitted, it is drawn on the local screen. As seen in Table 1, some flag values are assigned to see if a received data is related to pages or notes. The MyAsyncTask class will run properly according to the data. For the precise note synchronization, we have to consider the resolution mismatch of an Android device. While iphones are produced by only a single company, Android devices are built by different manufacturers. Due to Android s openness, device vendors are free to produce a wide variety of different mobile devices. Hence, even though the product model of devices is the same, their screen sizes might be different. In these circumstances, synchronization problems could occur among devices during a meeting. Due to the screen resolution mismatch, a note of a device may be drawn at the different position on other device. The smart meeting application adjusts for the difference of the screen size by applying a mapping algorithm. According to the mapping algorithm, a device needs to send its screen size as well as a note coordinate to other devices. Each Android device stores the screen size of the sender and calculates the right position where the received note will be drawn. Table 2 shows the mapping algorithm at the source code level. Table 2. Adjusting the Different Screen Resolution double result_rate_x = my_displaysize_x / received_displaysize_x; double result_rate_y = my_displaysize_y / received_displaysize_y; float tmp_x_loc = Float.valueOf(tmp_location_x).floatValue(); float tmp_y_loc = Float.valueOf(tmp_location_y).floatValue(); float my_x_loc = (float) (tmp_x_loc * result_rate_x); float my_y_loc = (float) (tmp_y_loc * result_rate_y); 4. Implementation of Smart Meeting Application We have developed a smart meeting application on the Android platform [6-8] which is one of the major mobile frameworks. Android 4.0 (API level 14) or later provides the Wi-Fi Direct APIs that consist of necessary Java classes and methods. Since our application is based on Wi-Fi Direct, it can be used without Internet connection. It is a useful feature for applications that share presentation files and events among users. The application development environment has included the APV PDF viewer [9], Eclipse Juno [10], JDK, Android SDK, and NDK. An Android smartphone is required to run Android platform 4.0 or higher version for WiFi-Direct API. Once the meeting application starts, an application user tries to search other users around by using the Discover button at the upper right corner. According to search results, the user can choose the connection or disconnection. In the meeting application, there are two roles a group owner and a participant. The group owner is a person who creates a virtual meeting room to discuss some agenda and organizes a meeting. The Copyright c 2014 SERSC 47

6 participant can log in the meeting group and compare notes about the agenda. Therefore, the group owner has the permission to accept or reject a user request to join the meeting group. If the request is accepted, the user becomes a member of the meeting group. After the meeting participants have joined, the group owner can distribute a meeting material among the participants via WiFi-Driect connection. A "File Explorer" button on the main screen of the group owner will be activated and the participants will be waiting for a meeting file in PDF format via socket connection. When the group owner clicks the "File Explorer" button to send the meeting file, the directory structure of the local storage displays in the form of ListView. By selecting the meeting file, the group owner can send it to the all the waiting participants. Figure 3 shows the initial screens of both the group owner and the participant after the meeting material has been transmitted successfully. As soon as the meeting file is received, it will be open immediately on the participant device. After the initial connection setup has been finished, the socket connection remains available between the group owner and the participant. The group owner can wait to receive questions from the participant or transmit the updated page number of the meeting file. Whenever the group owner changes the page number of the meeting file by using the scroll bar or volume button on the device, the updated page number is sent to the participant and then the page of the presentation file on the participant device will switch to that page. (a) Group owner (b) Participant Figure 3. Initial Screen Shots of Group Owner and Participant The participant shown in Figure 4 (b) can ask questions to the group owner using an option menu shown in Figure 4. In Figure 4, the option menu contains four menu items page moving, searching, question/note deleting, and asking. To avoid the communication confusion during the meeting, the only participant who has the permission to ask can send a question to the meeting participants including the group owner. 48 Copyright c 2014 SERSC

7 (a) Group owner (b) Participant Figure 4. Requesting for Permission to Ask As shown in Figure 5, the group owner can accept or reject the request for questioning by taking into account meeting situations. When the "Asking" menu item is chosen on the participant device, a predefined flag value is transmitted to the group owner. Upon accepting the request for questioning, the group owner enters the standby mode to receive comments or opinions from the authorized participant. (a) Group owner (b) Participant Figure 5. Accepting or Rejecting the Request of the Participant Copyright c 2014 SERSC 49

8 Figure 6 shows the participant shares some notes on the presentation slide with the group owner. The note can be lines, arrows, circles, stars, rectangles, or short text messages. The participant has to send the coordinates as well as the contents of the notes to the group owner. On the basis of the coordinate data, the group owner draws the notes on the slide. For the precise note presentation, we should consider the different size of the screen. Our application could run on mobile devices that occasionally have different screen size. Even if we use mobile devices with the same product model, their screen size would be different. Therefore, some notes of the group owner would be represented at the different location on the audience device. To address this issue, the note producer sends note contents, note location, and screen size information. The note receivers map the note location to the proper position of their screen. The screen size can be acquired from the system information provided by the Android platform. As you see in Figure 6, the notes of the participant are drawn in red and the others are represented in green. The group owner can answer to the question using the same note functionality as the participant asks a question. As mentioned above, the answer notes will be displayed in red on the screen of the group owner. (a) Group owner (b) Participant Figure 6. Sharing Comments on the Presentation Slide 5. Conclusions and Future Work We have introduced a novel meeting Android application based on Wi-Fi Direct which is supported on Android 4.0 or later. The meeting application is applicable for informal and quick group presentations when meeting facilities including beam projectors and computers are not available. The first feature of the application is that Internet connection is not required to use the application. Meeting participants can create a meeting group using Wi-Fi Direct without Internet access. Once all the participants are connected, they can communicate with one another via socket connection. Secondly, as the group owner starts and coordinates the meeting, all the participants share presentation files or comments during a meeting. Finally, the meeting application makes it possible to display the same page and notes on the screen of 50 Copyright c 2014 SERSC

9 the participant using page and note synchronization. We also address the issue of the screen resolution difference across Android devices using the automatic mapping function. As future work, we are going to enhance the remote control functionality by adding new features such as highlighting and word finding. In addition, we plan to develop a new drawing algorithm for the elaborate note presentation. There is still room for improvement in simultaneously sharing complex notes among the participants. One of the most interesting future tasks is to display handwritten Korean characters in an effective way. The current version of the application has a limitation on representing relatively small-size Korean characters. Acknowledgements This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2012R1A1A ). References [1] Gartner highlights key predictions for it organizations and users in 2010 and beyond, (2010). [2] Google Play, (2013). [3] Wi-Fi Direct, (2013). [4] Android APIs for Wi-Fi Direct, (2013). [5] J. Y. Jung and D. K. Kim, Development of an Instant Meeting Android Application Using Wi-Fi Direct APIs, Communications in Computer and Information Science, Springer, vol. 340, (2012), pp [6] Android developer site, (2013). [7] N. Gandhewar and R. Sheikh, Google Android: An Emerging Software Platform For Mobile Devices, International Journal on Computer Science and Engineering (IJCSE), (2010). [8] M. Gargenta, Learning Android, O'Reilly, (2011). [9] APV PDF Viewer, (2013). [10] Eclipse Integrated Development Environment, (2013). Authors Dong Kwan Kim is an Assistant Professor in the Department of Computer Engineering at Mokpo National Maritime University. His research interests include dynamic software updating, run-time systems, and mobile programming. Jae Yoon Jung received his B.S. degree from Catholic University of Pusan in He develops mobile applications at a startup company. Copyright c 2014 SERSC 51

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