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1. Murmur supw lt thepassword gt After that from any other computer install the client and connect to the server using the SuperUser account and the password you set in the previous step Now it is time to create the channels learning room Then create a group named Teachers then edit the ACL permissions for this group by removing Make channels and Write ACL permissions For each created channel remove the Speak Write ACL Make Channel Make Temporary Channel Mute Deafen and Whisper permissions for the in special group Then add the teachers account to the Teacher group And that is all for the Mumble Server configuration Figure 5 C Client Configuration and Management The end users students teachers and admins can connect to the server using the Mumble client applications get it from 9 For users who are able to use the mouse and the keyboard they have to install the latest version of the Mumble client and install only the client application Then they have to adjust the audio tuning wizard Then they have to connect to the server required information are the server IP or name a real user name and the password configured in the murmur in Then the users can connect to the available learning rooms and select the one that he wants to join However for those users who cannot use the mouse or the keyboard or who cannot read the text on the screen they2. 4 10 engine for the Arabic spoken phrases It is based on the recently developed Google Speech API It is speaker independent that means that any user can use it and it will recognize the spoken phrase accurately regardless of the specific personal feature of each user voice without the need for training or retraining It supports the Arabic language with several Arabic accents Egypt Saudi Arabia Algeria etc The accuracy is very high and it can reach up to 100 in the case when several simple rules are followed speaking clearly and loudly and disabling the recording enhancements of the microphone and adjusting the recording level to 70 without boosting The mechanism is as follows c f Figure 1 e the user speaks a phrase then we record his her voice in a file e Several sound processing are carried out noise removal filtering silence removal etc e The file encoding is then converted to flac encoding with the required sampling rate of 16 000 and mono channel e The resultant file is posted to google servers using the HTTP protocol with some parameters that we set for them Lang parameter can be any of the supported languages ar Sa Saudi Arabia ar Eg Egyptian etc as in the following link http www google com speech api v1 recognize xjerr 1 amp lang ar Eg amp client chromium e Google Speech API servers convert the speech into text and return the text back to our application using JSON format e Th
3. and Terriberry T 2012 Definition of the Opus Audio Codec IETF RFC 6716 Comparison between Mumble Skype and Ventrilo https mmo mumble com help comparisonchart Henning M 2004 A New Approach to Object Oriented Middleware IEEE Internet Computing 8 66 75 http dx doi org 10 1109 MIC 2004 1260706 Khan S Qureshi K and Rashid H 2010 Performance Comparison of ICE HORB CORBA and Dot NET Remot ing Middleware Technologies International Journal of Computer Applications 3 15 18
4. have to ask someone to install the software package that we have developed and put a shortcut in the S A E Mohamed et al Teachers Sheikhs A Students Mumble Clients and Applications Administrators Figure 5 The system can have many virtual learning rooms each one with a teacher and a number of students Startup Menu so that it starts with the system can be obtained from http quranbyvoice asites org A simple form asking them to fill the basic information will appear during the installation The application contains eve rything they need to connect to the server including the Mumble client After that they will be able to make use of the application and the system independently without the assistant of any other person D System Management An integral part of the system is the system management application We have developed a web application for managing the scheduling timetabling and assisting the client application for people with special needs This web application must be hosted in a webhosting server that is accessible publicly The administrators of the web application have several duties to be done 1 Create the list of the available Miqr ah room names to be identical to those in the Mumble server This will be used by the developed voice controlled application 2 For each Miqra ah room name they have to record a sound file in wav format containing the name and upload that to the
5. we have developed a virtual learning system Electronic Miqra ah Scientists can supervise re motely the registered students Students from different ages can register from anywhere in the world given that they have Internet connection Students can interact with the scientist in real time so that they can help them memorize Tahfeez guide them for error correction and give them lectures or lessons through virtual learning rooms The targeted groups of users can be non blind people blind people manual disabled people and illiterate people We have developed this system such that it takes the commands via voice in addition to the normal inputs like mouse and keyboard Users can dictate the commands to the system orally and the system recognizes the spoken phrases and executes them We have developed an efficient speech recognition engine that is speaker independent and accent independent The system administrators create several virtual learning rooms and register the licensed scientists Administrators prepare a daily schedule for each room Students can register to any of these rooms by pronouncing its name Each student is allocated a portion of time where he she can interact directly by voice with the scientist Other students can listen to the current student s recitation and the error corrections guidance or les sons from the scientists How to cite this paper Mohamed S A E et al 2014 Virtual Learning System Miqra ah for Qur
6. Journal of Software Engineering and Applications 2014 7 195 205 ose Scientific Published Online April 2014 in SciRes http www scirp org journal jsea oo Research http dx doi org 10 4236 jsea 2014 74021 Virtual Learning System Migra ah for Quran Recitations for Sighted and Blind Students Samir A Elsagheer Mohamed 2 Allam Shehata Hassanin Mohamed Taher Ben Othman Computer Engineering Department College of Computer Qassim University KSA 2 3 g Faculty of Engineering Aswan University Aswan Egypt Electronic Research Institute Giza Egypt Email samhmd qu edu sa samirahmed yahoo com almohager093 yahoo com maathaman qu edu sa mtothman gmail com Received 1 December 2013 revised 2 January 2014 accepted 9 January 2014 Copyright 2014 by authors and Scientific Research Publishing Inc This work is licensed under the Creative Commons Attribution International License CC BY http creativecommons org licenses by 4 0 Abstract Quran has ten famous recitations and twenty different narrations It is well known that the best way is to learn from qualified and authentic scientists Sheikh s in one or more of these narra tions Due to 1 the widespread of the Internet and the ease of use and availability of computers and the smart phones that enables access to the Internet 2 the business of people hindering them to attend physical learning environments and 3 the very few number of elder licensed scientists
7. an Recitations for Sighted and Blind Students Journal of Software Engineering and Applications 7 195 205 http dx doi org 10 4236 jsea 2014 74021 S A E Mohamed et al Keywords Virtual Learning Speech Recognition Quranic Recitations Learning Systems 1 Introduction The Holy Quran 1 2 also transliterated Qur an or Koran is the book literally meaning the recitation is the main religious text of Islam It is the verbatim words of God Allah Quran was revealed through angel Ga briel from Almighty God to the prophet Muhammad may peace be upon Him There are several sciences of the Holy Quran One of them is how to read correctly according to specific rules Tajweed Quran is the basic science Muslims should learn and practice Tajweed should be done accord ing to rules of pronunciation intonation and caesuras established by the prophet Muhammad In addition to Tajweed Quran memorization is of extreme importance for Muslims Quran memorization and learning are among the best ways of worship that close to Almighty God because of their numerous benefits as stated in the Quran and Sunnah 1 There are ten famous Quran recitations a k a reading or Qira ah In each recitation there are two famous narrations Rewayah The most popular reading is that of Hafs on the authority of Asim Similarly each melodic passage centers on a single tone level but the melodic contour and melodic passages are largely shaped by th
8. and tested and it works perfectly We believe that this system can be extended to be used for similar activities to conduct remote distance and virtual learning sessions for people having blind ness and manual handicap Funding This work is sponsored by Noor ITC www nooritc org project no NRC1 29 References 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Islam City Website http www islamicity com mosque quran Islam Way Website The Most Famous Broadcast Website about Islam http en islamway net Quran Readings Wikipidia English Webpage http en wikipedia org wiki Qur 27an_recitation Carnegie Mellon University 2010 Sphinx Speech Recognition Toolkit http cmusphinx sourceforge net Lamere P Kwok P Gouvea E B Raj B Singh R Walker W and Wolf P 2003 The CMU SPHINX 4 Speech Recognition System Proceedings of the IEEE International Conference on Acoustics Speech and Signal Processing ICASSP 46 37 51 Abushariah M A M Ainon R N et al 2010 Natural Speaker Independent Arabic Speech Recognition System Based on Hidden Markov Models Using Sphinx Tools 2010 International Conference on Computer and Communica tion Engineering ICCCE Kuala Lumpur 11 12 May 2010 1 6 Satori H Harti M and Chenfour N 2007 Introduction to Arabic speech recognition using Cmusphinx System In formation and Communication Technologies In
9. bility he she has to use the other program This program in tegrates the speech recognition engine described in Section HI This program has no GUI it starts when the Windows start and runs in the background It periodically play a beep sound if the user says in Arabic Start the program the programs starts to interrogate the users by pronounce the available commands and wait the user to dictate the required task When the user says any of the available phrase to the microphone the speech recog nition engine recognizes the spoken phrase command and execute it The main menu of the program is as follows no GUI only voice announcement of the choices 1 Listen to the titles names of the available channels virtual Migra ah rooms In this case the program fetches the available virtual Miqra Ah names from the server and the corresponding sound files prerecorded in the management web application please refer to Section DV D for more details Then the program plays these files one after the other 2 Listen to the schedule for today In this case the program fetches the schedule for today Mecca time zone prerecorded in the management server The program plays the sound file for the Migra ah name then the start time and the end time It repeats until finishing the whole schedule The time is pronounced automatically for example if it is from 05 35 am the program will say the corresponding components by voice From five hou
10. dictate the commands by voice and the system can recognize them accurately and execute them This feature allows the blind illiterate and manual disabled people to make use of the system exactly like the non disabled people who are able to use the mouse and the keyboard and read from the screen The rest of this paper is organized as follows In Section II we present the related works We describe the In vented Speech Recognition Engine in Section III Then we present the used system for the voice communica S A E Mohamed et al tion over the Internet namely Mumble VoIP in Section IV We present the whole developed system in Sec tion V The conclusions and the future directions are given in VI 2 Related Works After a thorough and deep search we could not find a system like the one that we have developed When searching the Internet we found several institutions claiming that they provide electronic Miqra ah Once examining them we found the existing solutions are very modest consisting in using Skype or Paltalk to create a single unmanaged voice chat room The first electronic Migra Ah that we found is using Paltalk by creating a room named Riyadh Aljannah For Learning Quraan for men or Riyadh Aljannah For Learning Quraan for women They are located in All rooms Midlle East gt Islam Once the user join that room the room admin usually the Sheikh can give the lesson select any of the users and allow him
11. e access control lists Sound quality Mumble uses Opus 16 which is standardized by the Internet Engineering Task Force IETF as RFC 6716 Opus is the best for interactive speech and music transmission over the Internet The sound quality is excellent compared to all the other existing software It supports noise reduction and automatic gain control It provides the lowest latency resulting in faster communication It also incorporates echo cancellation that per mits the use of speakers as well as headphones without echo Please see Figures 2 and 3 S A E Mohamed et al fullband stereo fullband Opus a MP3 super wideband G 722 1C Mie wideband narrowband Le 8 16 32 64 128 bitrate kb s royalty free open source free license not open source licensing fees not open source Figure 2 Comparison between the most known codecs for the quality aganest the bitrate source http opus codec org comparison Bitrate kbps channel 40 oa ouy y sw Avjaq Phone quality High fidelity narrowband C wideband gt wideband Figure 3 Bitrate latency comparison source http opus codec org comparison 5 Developed System After describing the essential components of the system namely the speech recognition engine and the voice over IP multiparty conferencing system Mumble let s present the whole system including the developed ap plications to provide t
12. e accuracy of the recognized text by Google is very bad in many cases For Arabic it is around 50 Thus we have added several post processing phases on the text to increase the accuracy e The post processing phase consists of using the approximate string searching and normalization within the expected spoken set of phrases e We have carried several experimentations of the post processing phase with 14 different approximate string matching algorithms 1 1 13 which are as follows S A E Mohamed et al Get speech Storage in a file Noise removal Filtering Silence removal puw Postprocessing Convert to string searching and a Flac encoding normalization Google Speech API Text in JSON format servers Figure 1 Block diagram of the speech recognition engine Smith Waterman Smith Waterman Gotoh Smith Waterman Gotoh Windowed Affine Q Grams Distance Needleman Wunch Monge Elkan Levenstein Jaro Winkler 9 Jaccard Similarity 10 Euclidean Distance 11 Dice Similarity 12 Cosine Similarity 13 Block Distance 14 Chapman Length Deviation e After applying each algorithm to recognize many texts recognized by Google speech API to the names of the names of Recitations and several categories of related and un related phrases we found that the best al gorithm that can be used to improve the accuracy for the phrasal string is Levenstein 13 We ha
13. e reading rules creating passages of different lengths whose temporal expan sion is defined through caesuras 3 These ten recitations consist of 7 Mutawatirs a transmission which has independent chains of authorities so wide as to rule out the possibility of any error and on which there is consensus and 3 Mashhurs these are slightly less wide in their transmission but still so wide as to make error highly unlikely ways of reading 3 Muslim scientists specialized in the recitation and the rest of Quran sciences learn the recitation from quali fied and elder licensed scientists Sheikh Each one of these licensed scientist is linked in a transmission chain up to the prophet Muhammad For more details about the Quran and its sciences please refer to 2 People seeking to learn the Quran are usually go to special schools locations where a group of students are assembled and instructed by one qualified Muslim scholar These special schools are known as Miqra ah The main purpose of Miqra ah is for teaching Quran recitations and Tajweed as well as the rest of Quran Sciences Due to the lack of sufficient number of licensed Scientists and the burden of the daily routines very few stu dents are going to Miqra ah which is usually located in Mosques With the widespread of Internet and its availability the vast widespread of the smart phones having Internet access and the ease of use of these devices it is important to develop a system em
14. he end users students teachers and admins can connect to the server using the Mumble client applications For users who are able to use the mouse and the keyboard they have to install the latest version of the Mumble client and install only the client application Then they have to adjust the audio tuning wizard Then they have to connect to the server required information is the server IP or name a real user name and the password con figured in the murmur ini Then the users can connect to the available learning rooms and select the one that he wants to join However for those users who cannot use the mouse or the keyboard or who cannot read the text on the screen they have to ask someone to install the software package that we have developed and put a shortcut in the Startup Menu so that it starts with the system A simple form asking them to fill the basic information will appear during the installation The applications contain everything they need to connect to the server including the Mumble client After that they will be able to make use of the application and the system independently without the assistant of any other person B Server Management and Configuration The whole system consists of Mumble Server Mumble Clients and the Management frontend Here we pro vide the guide for setting up each of the components of the system The Mumble server is essential for doing most of the VoIP heavy works organizing the channel
15. he virtual learning environment namely the electronic Miqr ah See Figures 3 and 4 First let s present the overall architecture of the system The system consists of the following component e Murmur Server software e Mumble client software programs depending on the platform e Management and scheduling Web Application e Speech recognition application for the blind illiterate and manual disabled people e Licensed Scientists attached to each channel according to the daily schedule e System administrators S A E Mohamed et al User using Smart Phone User using Tablet User using PC Hand disability user using PC l Blind user J using PC E j 7 fiii Z Management Server System Administrators Mumble Server Figure 4 Overview of the system for a single channel Miqra ah e Students non blind blind illiterate and manual disabled people A User Interface Two programs can be used depending on the user non blind who can use the mouse and keyboard or people who are blind manual disabled or illiterate In the case where the user can use the mouse and the keyboard he can simply launch the client program from the Desktop the laptop the Smartphone or the tablet Then register into server and connect to the last channel Miqra ah learning room he she can move from one Miqra ah to another by the mouse and the keyboard However if the user is blind or have hands disa
16. low users having older versions of Mumble clients lt v1 2 3 then set that value to 100 In this case the quality of the voice may degrade as the server revert to the older codecs for all the users However if all the us ers will be forced to use the latest version then it is safe to put that to 0 In this case the quality of the voice will be excellent 0 Always enable Opus 100 enable Opus if it s supported by all clients opusthreshold 100 Regular expression used to validate channel names change it to be as follows to allow Arabic names and some special characters channelname w Y J A IJ Regular expression used to validate user names change it to be as follows to allow Arabic names and some special characters username w F JWAY N WAEW J If this options is enabled only clients which have a certificate are allowed to connect very important to al low clients having old versions to connect It is also important to allow the by voice controlled desktop applica tion to operate properly certrequired False The rest of the options should be changed only in the case when you need to use them Please note that there is no need to use DBUS nor ICE Internet Communication Engine 18 19 After launching Mumble server you have to put a link in the Startup menu so that it starts whenever windows Starts Then you have to setup the SuperUser password using this simple command
17. mizability vey high ee ae OU Ors Not available Not available the client to match your preferences ee for fr rver unlimi ith Maximum users Unlimited ee ted wit 10 on conference call licensed server Comments amp Rich text include images and links as desired Plain text Not available Channels Great Mumble is scriptable from many Scriptability languages including C Java NET Not available Not available Python PHP Ruby and Objective C administrative interface and features high sound quality and low latency Communications are encrypted to en sure user privacy Mumble is free and open source software It is a cross platform that means that the both client and server can run under Windows Linux and Mac iOS In addition there are client applications for the most common operating systems of the smart phones namely Android and iOS That means that the users can con nect to the system from their Desktop Laptop Mobile phone tablet and notebooks provided that they have In ternet connection on these devices We are going to describe the main features of Mumble in this Section Channel hierarchy When installing the mumble server a k a murmur the server creates on root channel called root System Admins can create as much channels as they wish under the root channel in a hierarchy Us ers in each channel can talk together and all can hear the voice of anyone who is talking Admins can set per missions for each channel using th
18. r and thirty five minutes AM Please refer to Section DV D for more details S A E Mohamed et al 3 Listen to the schedule for tomorrow Exactly like the previous menu choice but for tomorrow 4 Join the last Miqra ah room you have connected to In this case the program launches the Mumble client application connects the user to the server it creates a specific username for the user containing the time and the real user name the reason for that is to make a queue allowing the users entering the room to be in the top of the list and those entering recently will be in the bottom of the list The program makes the users joining the virtual room he she were connected to the last use of the program 5 Join a channel by pronouncing its name The system will ask the user to pronounce the name of the Migra ah room he she wants to join Note that the user knows the channel names from the main menu Then the user says the name of the channel and the system recognize the required channel then the program launches the client program Mumble and then connect to the voice server and makes the users to join the desired channel 6 Stop or close the program The system will close the Mumble client and the user is removed from the users in the room he she were connected to 7 Listen to the user guide The system plays back a recorded voice file explaining how to use the program efficiently as well as the rules of using the system T
19. s ane to the Ventrilo protocol communications Platform Windows partial OS X support Support Windows Linux and OS X some codecs not available no Windows Linux and OS X Linux support Certificate and password based authentication Authentication Strong certificate authentication ensures Password based Password based account security and user authenticity Good Ventrilo uses several Voice Ouclit Great Mumble uses the cutting edge codecs such as Speex and GSM Average Lower bitrate and high y CELT codec for maximum clarity though not all codecs are encryption overhead reduce quality available on all platforms Noise canceling Automatic Not available Automatic Push to talk Available Available Not available Linked channels Available Not available Not available User groups Available Not available Not available Text messages Per channel and per user private messages Not available Per conference and per user Administration pone ao eae channels Manage Requires external web interface Not available users and modify permissions in realtime Great powerful ACLs allow for fine grained Coarse users are either Access Control Not available control over all aspects of the server administrators or normal users Mumble will automatically lower Volume other system sounds when someone is i i h Not available Not available Attenuation talking Play with music and game sound on you ll never miss a message eas igh l kin Custo
20. s managing the ACL and client connectivity To set up the Mumble Server one server machine is required it can be dedi cated shared or Virtual Private Server in the cloud The Supported OS is Windows Linux and Mac OS The server must be connected to the Internet and have at lease on public IP address A DNS record for that IP ad dress with the Server name is optional After preparing the server that will host the Mumble Server the firewall has to be configured to open port 64 738 The bandwidth for the network connectivity for that server should be not be high Mumble server uses the minimum bandwidth for with the best voice quality compared to the other solutions In Mumble documentations it is stated that at least 40kbps for each user given that all the users talks at the same time and all should here all Mumble is all to all VoIP However we are not going to use it like that for two reasons 1 in any of the learning room the teacher should have the right to speak at any time while only one students can talk and the rest of students should listen otherwise managing the learning room would be very difficult 2 if we allow all to all scenario the bandwidth requirement will be very high Because of that only the teacher and one of the students are allowed to talk at any given time in each learning room This means we have two to all scenario Using an intelligent mechanism coded in the client program the user name of the student is prefixed
21. server 3 They have to create the schedule of the available lessons every day It is mandatory also to create the schedule of the next day All these duties are essential for the correct operation of the voice controlled application It 1s very important that the information stored in this web application be identical and coherent with that found in the Mumble server 6 Conclusions and Future Directions In this paper we have presented a virtual learning system that we have developed to provide a real multi virtual room electronic Miqra ah The system consists of several components The system can be used by non blind people We have integrated a speech recognition engine that we have invented Another application using that speech recognition engine is developed It allows the bind manual disabled and illiterate people to efficiently and easily use the system They can have full control on the system using voice driven commands without having to use the mouse or the keyboard or to get help from other people The system incorporates a very performance efficient open source and reliable all to all voice chatting ap plication namely Mumble VoIP Licensed Sheikhs scientists as well as the students can be connected from their devices desktop laptops and Smartphone s and conduct a lesson Miqra ah session from their locations without having to go to schools or institutes S A E Mohamed et al The system is implemented
22. ternational Symposium Fes 3 5 July 2007 4 Pages Hyassat H and Abu Zitar R 2008 Arabic Speech Recognition Using SPHINX Engine International Journal of Speech Technology 9 133 150 Cambridge 2010 HT K Hidden Markov Model Toolkit Speech Recognition Toolkit http htk eng cam ac uk Young S Evermann G Gales M Hain T Kershaw D Liu X Moore G Odell J Ollason D Povey D Valtchev V and Woodland P 1996 The HTK Book Cambridge University Press Cambridge Shaikh M Memon N and Wiil U K 2011 Extended Approximate String Matching Algorithms to Detect Name Aliases 2011 IEEE International Conference on Intelligence and Security Informatics ISD Beijing 10 12 July 2011 216 219 Navarro G 2001 A Guided Tour to Approximate String Matching ACM Computing Surveys 33 31 88 http dx doi org 10 1145 375360 375365 Gusfield D 1997 Algorithms on Strings Trees and Sequences Computer Science and Computational Biology Cambridge University Press Cambridge 263 264 http dx doi org 10 1017 CBO97805 11574931 Mumble An Open Source Low Latency High Quality Voice Chat Software http mumble sourceforge net Rothbucher M Habigt T Feldmaier J and Diepold K 2010 Integrating a HRTF Based Sound Synthesis System into Mumble 2010 ZEEE International Workshop on Multimedia Signal Processing MMSP 4 6 October 2010 24 28 http dx doi org 10 1109 MMSP 2010 5661988 Valin J M Vos K
23. to talk all the others listen There are several problems with the solutions provided by Paltalk 1 Annoying ads usually containing of fensive images videos 2 Only one room no varieties 3 Only one speaker the rest only listen 4 No an nounced schedule people have to connect and wait until a lesson starts 5 Not suitable for blind people nor manual disabled people as they have to use the mouse and the keyboard and read what is on the screen The rest of the solutions consist in using Skype The owner of the claimed electronic Miqra Ah creates a user account on Skype and announces it Anyone who wants to join that Miqrh Ah has to add that user to his contact list and after approval from the owner he can voice chat with that user when the owner is online Examples of the existing Skype accounts for that purpose are magr2aonline women Magrat Quran quraan 21 and almagraa alquranya Skype shares the same drawbacks stated before for Paltalk Furthermore it has several drawbacks compared to the solution that we provide Skype is really perfect for one to one call However for one to many calls it is not suitable and the performance and the voice quality is very bad hindering it from being suitable for such task In addition there is no manageability with Skype you cannot control who can talk now for multi party calls with Skype at most three or four persons 3 Speech Recognition Engine We have invented a speech recognition
24. ulating the physical Miqra ah In this paper we present a system that we have developed to serve as electronic Migra ah through the Internet The system administrators register the licensed scientists into the system They create several virtual learning rooms in the system and prepare a daily schedule for each room depending on the availability of the scientists Each time slot in the schedule is assigned to one of the scientists Using a program scientists connect remotely from their homes or any location having Internet access to the system to the specified virtual learning room Students have access to the system through the Internet connects to the system and choose the virtual room that they want to join After that the scientist can teach them using voice broadcast one to all He can ask the students to recite and correct their recitations one by one All the activities of the physical Miqra ah are available in the system However people stay at home or work or in any place they have Internet connection and the client program The system is cross platforms compatible supporting Windows Linux and Apple OS The client application is also available for the most famous smart phones namely those running Android and iOS Thus both the scien tists and the students can access the system from their mobile phones in addition to the desktop and laptop computers The system includes very accurate speech recognition mechanism Thus students can
25. ve implemented this mechanism and then we have tested it on the recognition of the spoken control commands e g start the program end the program I want to list to today schedule I want to listen to tomor row s schedule I want to listen to the help desk I want to listen to the usage instructions or user manual etc and the names of the channels Miqra ah The accuracy is very promising and it can reach up to 100 in all of the tests that we carried out given that the settings and the rules stated before are respected oS Oa a a T 4 Voice over IP System Mumble Murmur After a thorough and intensive search for a suitable Internet communication system that enables the Scientists and the students to communicate with each other we come up with several possibilities Paltalk Skype Ventrilo and Mumble We have studied each one and the features provided by each of them please refer to Table 1 Mumble 14 15 is a Voice over IP VoIP software system primarily designed for use by gamers Mumble uses a client server architecture which allows users to talk to each other via the same server It has a very simple S A E Mohamed et al Table 1 Comparison between mumble ventrilo and skype source 17 Mumble Ventrilo Skype EP treniciy low communioations happenin High even low ping servers High Skype is optimized for casual Latency pe have a 1 2 second delay due chatter not realtime when it counts milliseconds not second
26. with time he she joined the lesson room In this case those who connects first will be in the top of the list thus the teacher will be able to know who has the turn Once the turn of cur rently selected user is over he she mutes that user and un mute the next user in the list The bandwidth requirement thus should be estimated as follows 2x of rooms x of channels quality_factor S A E Mohamed et al where the quality_factor ranges from 40 kbps to 110 kbps highest quality This value should be included in the configuration file of the Mumble Server murmur in1 The latest Mumble package for the appropriate platform has to be downloaded and installed on the server only install the server software and do not select the client software during the installation Please follow the installation guide for the Mumble server available on Mumble site and then change the following in the mur mur ini configuration file Password to join server Very important and should match what is stored in the client application and known by the non blind people serverpassword PPPPP Maximum bandwidth in bits per second clients are allowed to send speech at Set at your requirements higher means better quality but requires higher server bandwidth bandwidth 72 000 Maximum number of concurrent clients allowed Users 1000 Amount of users with Opus support needed to force Opus usage in percent This is very important if you will al
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