Broadcast Live event with multiple smartphone video camera setup

Friends I earlier wrote about Bandwidth bonding , video streaming apps , Facebook live streaming etc. Recently I was trying to find way to use multiple smartphone camera and produce a live event.

Professional broadcast facilities are available to connect broadcast cameras to switching system and telecast the event live but my objective was to use our smartphone camera and create a free or low cost solution for quality broadcast. Now Smartphone cameras can also give quality HD video output so use our smartphones and broadcast a live event.

multiple smartphone video camera setup

Task in mind

I wanted to receive live video from multiple smartphone camera into my laptop and use these live video sources for producing the live event. Then i wanted to stream this video output to either YouTube, Facebook or some other streaming server for public distribution.

Difficulties in setting up multiple smartphone video camera setup

  • How to connect smartphone video to laptop – Using USB wired connection will limit the distance of camera so i wanted to connect smartphone with my laptop through Wi-Fi network.
  • How to send live video from smartphone to laptop – Send live video from smartphone to laptop over wi-fi network requires video streaming so i used IP Webcam app to stream video from smartphone over local Wi-Fi network.
  • Application to receive video from multiple smartphone – In my earlier article about video production and streaming app, i discussed about some Wirecast, vMix and OBS. I selected vMix as this application is free and it can receive multiple video streams.

Create multiple Smartphone video camera setup

Task here is to send video from smartphone to laptop and collect all video stream. Produce the live event with these video streams and then sent it for streaming to server.

Live video from Smartphone to Laptop – I installed IP Webcam app in my smartphone. When you open the app, it shows multiple configuration options for camera. At the bottom of app , there is a button to Start server. Once you click this button, IP Webcam app starts streaming server which can stream live video from cam. The live video screen on IP Cam app shows the URL of the stream. When you type or paste that URL in any mobile or laptop, you get connected to IP Webcam app of streaming mobile.The page opened on browser shows multiple options to fetch the stream from smartphone to laptop.
If your mobile is connected through public network ( mobile network) , your laptop will fetch stream through public network. If your smartphone is connected through local wi-fi network then streaming ip address will be local address so mobile will not consume your internet data. So its better to connect all smartphone and laptop through local network.
If you are already in some local network with Wi-Fi then there is no problem.Connect laptop and all smartphone to local network. If you don’t have local Wi-Fi network then you use a separate ADSL also to have internet and Wi-Fi network.
Alternatively you can connect your laptop to internet and create Wi-Fi hotspot through your laptop. The smartphones can connect to this laptop hotspot and join together in one network.

Receive live smartphone video stream in vMix – Receiving the video stream in your laptop is quite easy. IP Webcam builds the stream URL like http://(smartphone ip):8080/video . In vMix application click on Add Input->Web Browser. Here you enter your smartphone stream URL. Set browser width and height equal to the incoming video stream width and height. Click ok to complete the setup. You will start receiving smartphone live video in vMix.
In the same manner you can configure other smartphone video also and then start producing the live event.

Stream produced video – For streaming the live event, you configure the stream parameters. Click on the gear icon on left side of Stream button at bottom application tray. This will open Streaming settings window.Select the stream destination and then set other parameters according to destination. Save the setting. Click on Stream button to start streaming.

Limitation of multiple smartphone video camera setup

Qualitatively smartphone camera gives good video but focus remains a issue during movement. Auto focus for video is not fast which gives little defocused video during movement so slow camera movement is advised. Smartphone camera is quite compact and light weight so careful camera handling for smooth pan/tilt movement is required.Distance of wireless operation between smartphone and laptop depend upon Wi-Fi signal strength so never go beyond Wi-Fi limits otherwise video will freeze.
Tilt and Pan operations need careful handling. But smooth Zoom operation is not possible with smartphone video camera. Its good to place smartphones with some stand in fixed position for stable and focused frame.

Advantage of multiple smartphone video camera setup

  • Cost effective solution with good quality video
  • Compact setup
  • Limited equipment requirement – Laptop, Smartphone, internet


Producing live event with broadcast quality equipment is quite costly. It requires skilled manpower, equipment and finally funds. If you can compromise little on quality , you can use smartphones for live event. Just take care of smartphone camera handling, your video will look great.

Hindi Typing methods for Android Smartphone

Hindi Typing on Smartphone or Laptop has become quite easier. There are multiple methods for Hindi typing.Development of Hindi Typing methods has been gradual as Hindi is a complex script for typing purpose. Different types of computer keyboard layouts like Remington, In-script, Phonetic were used.

Evolution of transliteration method was most promising development for Hindi typing. Computer users are quite familiar with Latin script based keyboards so transliteration method helped to type Hindi using Latin  script based keyboard. Same QWERTY keyboard with added computer intelligence helps to print Hindi words quickly and easily.

Next stage displayed Voice typing. Efforts for efficient voice typing were going on for long but software algorithms were not efficient enough to interpret different human voices. But latest Google tools are quite smart to deal with these issues.

Latest Handwriting tools are gift of prevailing Smartphone technology with touch screen facility. Intelligent software recognize the handwritten character and print that on your Smartphone.

Hindi Typing methods for Android Smartphone

  • Hindi Typing using Keyboard
    • Transliteration – require Google Indic keyboard app
    • Hindi keyboard – require Google Indic keyboard app
  • Hindi Typing using Handwriting tool – require Google Indic keyboard app
  • Hindi Typing using Voice – Part of Android Operating system in Smartphone

Configure Your Smartphone for Hindi Typing methods

Install Google Indic Language app – The above three methods i.e Hindi Typing using keyboard and handwriting tool can be achieved by installing Google Indic Keyboard app from Google Play. Download and install the app from Google Play. Now go to any app where you want to type something.

Google Indic Language

  • If you long press the space-bar button on Android keyboard it opens the active keyboard options. You select English & Indic Languages for typing in Hindi or other Indian language.
  • Now your keyboard will show two tabs on keyboard like abc  अ  , you select for Hindi/Indic language typing.  When you select   , a small downward arrow button appears on right side of  . When you click on this downward arrow, three typing options for keyboard with transliteration method ( likhen -> लिखें  ) , keyboard with Hindi character ( लिखें ) and Handwriting tool appears.
  • On the upper right side of keyboard, you have option to select language out of Indic languages supported by Google Indic language app.
  • You can click on gear symbol also to configure Google Indic Language app for advanced options.

Google Indic Hindi KeyboardHindi Typing using Hindi Keyboard – This Google Hindi keyboard is little more advanced than old fashioned Hindi keyboards. For using this Hindi keyboard, you select 2nd option (लिखें  ) from Google Indic language keyboard options. When you click on any virtual keyboard character, suggested Hindi characters with Matra is displayed on upper portion of keyboard. For example click on क  then suggested option are like क का कि की कु कू के कै को कौ  . You need to practice this keyboard for Hindi Typing.

Google Indic Transliteration keyboardHindi Typing using Google Transliteration tool – This is most efficient and convenient method for Hindi typing for people who are familiar with Latin script based keyboards. For using this Hindi Transliteration keyboard, you select option ( likhen -> लिखें  ) from Google Indic language keyboard options. Transliteration method uses Latin script based keyboard to print Hindi characters. Hindi words are typed as per the pronunciation of the word. Google tool understands the word and most suitable word is printed. This tool simultaneously recommends suggestions also. You can choose correct Hindi word among the choices offered by tool for the characters typed in English.

Google Indic handwriting toolHindi typing using Handwriting tool – This method is quite useful for people who write Hindi. Handwriting tools use Smartphones touch screen for writing words and printing same on screen. For using this Hindi keyboard, you select option 3rd keyboard option from Google Indic language keyboard options. Writing with stylus pen can be more convenient than writing with your finger. This keyboard also offers suggestion for the written Hindi word.

Hindi Voice Typing – Google Voice typing tool is quite efficient for understanding your voice and printing the appropriate character. It has excellent capability to recognize correct word from different Hindi accent and voices. Earlier voice tools were quite heavy and processing power hungry but Google Voice tool works very efficiently in smartphones without any noticeable delay. Voice typing is like dictation where you give dictation to your smartphone using microphone. One of the problem with voice typing is ambiance sound. If surrounding sound is noticeable and interferes with your voice then your smartphone may not interpret your speech correctly. So you can’t use Voice typing in noisy places or public places. But Hindi typing with voice is quite fast as compared to other methods.


All above methods for Hindi Typing are user friendly and provide excellent software interface. Selection of any one out of these depends upon user. People who are not familiar with Latin script based keyboards may choose voice typing or Hindi Keyboard. People who are in practice of using English keyboards can have preference for Transliteration method. Voice typing is good for Hindi speaking person but require low ambience sound for correct speech interpretation.

Facebook Live from your Laptop – How To

Social media is playing key role in connecting with people. Day by Day World is narrowing down with more connectivity. Video, Audio, Images and Text messages can be sent to large group of people in seconds. Information sharing is much more convenient with different social media tools. Social media tools and network bandwidth together open options for more and more facilities. Now it is possible to organize a live event on Facebook. You can stream live video to Facebook servers which publish your content to your Facebook page.

How to do Facebook Live

First look at the requirements for live streaming to Facebook servers.

  1. Facebook account
  2. Good quality network connection
  3. Video source – Laptop inbuilt camera or use external camera or video capture
  4. Video encoding and streaming application

Lets discuss above points to understand the process better.

  • You can stream video to your Facebook page. So you must have an account on Facebook.
  • Good quality network connection is essential for video streaming. In case of video streaming , video content is uploaded to Facebook server so demand for upload speed matters a lot. How much upload speed you need? This depends upon the quality of video you want to upload. Quality of video depends upon video encoding parameters.If you compress more, quality will be lower. So understand the encoding parameters for maintaining good quality for your captured video. Generally 2 Mbps stream is good for general purpose but professional broadcast require more bandwidth which depends upon video resolution and compression parameters.
  • You can get video from single camera or multi-camera setup. Your laptop can capture video from inbuilt camera or you can use external USB camera also. In case of multi camera setup, collect the final output of multi camera setup ( produced output) and capture the video through some capture device. Multiple video capture devices are available in market. Blackmagic Intensity shuttle can be a good choice to capture external video.Its drives are supported by most of the applications.
  • Finally you need some application to encode video and encapsulate for streaming. In my last article about Video streaming applications, I discussed some of widely used application. My choice here is Open Broadcaster Studio (OBS) as this is completely free for usage.

Facebook Live – In few Steps

  • Connect your Laptop with internet.For safe side, test your network speed also so that video stream goes smoothly to Facebook server.You video data upload limits should be less than the average upload speed of network otherwise frames will be dropped and freezing will be observed in live video.
  • Open video streaming application. I am giving example here with Open Broadcaster Studio (OBS). Add video source to your OBS. Click on + button in Sources, then select Video Capture device->Create New. A pop up window will emerge which will show capture devices.From the drop down window, select your video capture device.Your video will be visible in preview window. You can then cut it for final output.
  • Now you need to configure video stream.Click on Settings button on right side. The settings window has option for Stream settings.Following settings need to be done.
    • Stream Type – Streaming Services
    • Service – Facebook Live
    • Server – Default
    • Stream Key – You will get this stream key from Facebook configuration page.After necessary configuration on Facebook page, collect the stream key and paste that here.

OBS Facebook live stream settings

  • Now login to your Facebook account and go to Facebook page where you want to do Live video streaming.
    • In Top menu option, Click on Publishing Tools
    • Publishing tools page will open. In left side menu, click on Videos
    • In this Videos section,click on +Live button to create a Facebook Live
    • A popup window will emerge showing the stream url. Stream Url consist of two parts. First part is Facebook server url and other is stream key. You copy this URL and stream key because this will be required for configuration in your streaming application.
    • Facebook live stream
  • Now go back to OBS and paste this stream key into OBS stream settings. Click apply and then OK.
  • Your system is now ready for Live video stream to Facebook. You can now click on Start Streaming in OBS. Without live stream signal, Facebook page shows Offline status which changes to Live after server receives live stream.

Facebook Live configuration is just for getting the unique streaming URL. Some other settings on Facebook page is like Title, description of live event which you can apply as per your requirement. The video streaming applications requires Facebook streaming URL ( complete URL or just stream key) which you may apply as per your application.

I hope, you would have got a broader idea of Facebook Live Event.

Low cost solutions for Broadband Bonding

For beginners, I will just like clear confusion between link bonding or link aggregation and load balancing. Both the methods use more than one connection and join them together. Load balancing devices distributes the data load between the multiples link with certain priority criteria. It helps to achieve redundancy in case of certain link failure. If one link fails, other links share the load. The load balancing device maintain connections between user and internet link for each session. The communication for each session goes through same data link. For example, you want to download some file, so the user session for this download will be connected through same particular link till end of the session. If other user also start file download and load balancing device allots him link-2 , then he will continue with same link till his session remains alive. The load balancing devices have several configuration parameters which allows to maintain priority among different links, manage link failure situations etc.

In case of Broadband bonding, true bandwidth bonding is achieved. Ideally you get the sum of each link.  The Broadband bonding device creates a virtual link by combining all the links. In this method, software algorithm collects incoming data and divides them between different links. The received data packets are repacketized after inserting this repacketization information. The reverse process of this repacketization is required at the other end of system to collects original data packets. Link bonding is much more complicated than just load balancing.

There are multiple hardware and software solutions available for Broadband bonding but most of them are costly. Different proprietary software for Link aggregation are developed by companies with their patent algorithm but most of them are quite costly.

After going through details of different products and solutions, I will like to mention two software cum hardware based solutions. First is Speedify and other is Zifilink ( Earlier name Watchy).

broadband bonding


Speedify is purely a software solution from the user point of view. Speedify is available free for usage upto 1 GB/month of Data transfer. Paid versions provide unlimited data transfer limit. You can download speedify application and install on your PC or laptop. It detects all available network connection including Wi-Fi, Ethernet and tethered devices. You can use only one connection through one adapter, means you can only use one Wi-Fi out of all Wi-Fi detected from a particular Wi-Fi network adapter.

The software application bonds all different network connections and sends data to Speedify servers which perform the reverse process of bonding. The solution depends upon the performance of speedify servers. Servers may limit the data transfer which ultimately affects the purpose of bonding. You are advised to test performance of speedify in your area with free data limit. If you achieve good result then you can buy paid limits otherwise drop the idea of Speedify. Performance tested for Speedify was below our expectation in India.


Zifilink is a hardware cum software solution. It’s hardware unit comes in two model i.e 3x or 8x. Difference is only number of bonding ports. 8x has limit of connecting 8 USB dongle while 3x has limit of only 3 connection bonding.

Broadband bonding process is performed at this hardware bonding router while reverse process is performed at cloud server. At present Zifilink has probably hired cloud servers from amazon. Zifilink is good low cost solution for Broadband bonding.

Zifilink hardware supports only USB dongle but no Wi-Fi or Ethernet connection. It has Ethernet port for device monitoring but not for link bonding. There is another issue that it has limited support for dongle drivers. So You need to use dongles which are supported by Zifilink router. Overall Broadband bonding performance of Zifilink is very Good.

Live Video Streaming applications – Review

Live Video streaming from ground event is becoming popular day by day. Earlier it was quite a difficult task because sufficient bandwidth was not available for live video streaming through mobile networks. Now 3G/4G networks provide a reasonable amount of bandwidth which can transfer live video streams. Generally 3G networks provide around 500-600 kbps of data transfer for live stream .This may not be sufficient for good quality video but highly compressed video can be sent live easily. 4G networks are supporting much higher data transfer speed so you can even live stream high definition videos also.

There are number of software applications which you can be used for live video streaming. Few of them are recommended here for reasons like simple user interface, better video encoding options, additional video production features etc.

live video streaming


Wirecast by Telestream is one of the best video production cum streaming application. Software demo is available for testing. Wirecast Studio cost around $500 and Wirecast PRO version cost around $1000. If you are planning to use application for some professional prupose then its worth to spend $500 .


  • Simple Graphic user interface
  • Multiple options for streaming to YouTube, Wowza etc.
  • Large set of predefined encoding parameters
  • Complete control of video encoding parameter for custom encoding
  • Best video production features
  • Multiple Predesigned video streaming profiles for different video resolution
  • You can take video output from the system but this feature is available in PRO version only.


  • No free app
  • Wirecast trail application comes with wirecast watermak

Open Broadcaster Studio (OBS)

OBS studio is an open source application. It offers similar streaming and production features as Wirecast. From the video encoding and streaming point of view, it is as good as Wirecast but video production interface is much better in Wirecast. Different layers of A/V is more easily managed in Wirecast than managing different scenes and sources in OBS.


  • Free application
  • Good for video encoding and streaming
  • Video recording facility available
  • Option for streaming to Youtube, facebook streaming service etc. Custom streaming server connection facility as well.
  • Large set of video production feature


  • Video production requires dynamic changes so toolsets should be always available in production interface. Wirecast display different production tools systematically that help for dynamic changes.OBS has most of the features but require more user friendly interface.
  • No predesigned video streaming profiles


vMix is a feature rich video production and streaming application. It also offers to record video. You can use playlist option to sequentially play list of a/v sources. vMix interface is better than OBS. It brought all the toolset in the primary interface like record, stream,add input, playlist etc. One of the good thing is production tools like cut, fade ,wipe are simultanesouly available in primary interface. You can cut one scene to other and then wipe other scene. This thing is even better than that of Wirecast. One more advantage with vMix is video output. It support external out from the application. You can get video output from some video render like declink  or HDMI.


  • Large set of feature for video production
  • User interface is good
  • Support multiple streaming servers like youtube, facebook etc. Custom stream option also available.
  • It gives Video out from application. This is useful feature if you want to record your produced output to some external recorder or you want to display produced output to different display screen.
  • 60 day free trail version is available


  • vMix is not completely free application. Some of the features like HD, SD, 4K resultion,  two external out, more than 2 camera requires paid version.The Basic free version offers only 768×576 resolution. But just $60 can upgrade your application for 1920×1080 resolution. I think , the cost of this HD version is quite nominal. Free version has restriction of only 2 camera input. But you get video streaming, recording and external output in free version also.


Wirecast is a good application but it’s a paid application. OBS Studio is completely free but little compromised for features and interface. But it can serve your purpose of video streaming without any limitation. vMix is a good application in terms of video production features and user interface. You can use vMix freely if you want to stream video upto resolution 768×576. If want to stream HD video then you need to pay some charges but its cheaper than cost of Wirecast

Hindi Voice Typing in your Laptop or PC

Efforts for efficient voice typing were going on for last several years but quality of outcome through these applications were not very accurate. But Google  developed a very efficient voice typing tool which support Hindi voice typing also. After testing this tool, some of my observations are:

  • This Google tool for Hindi voice typing is quite efficient. Its accuracy for voice to text conversion is more than 90 percent. Larger part of speech is correctly interpreted.
  • Punctuation need to be inserted later after voice to text conversion.
  • Speed of voice to text conversion is very good. You can maintain your normal communication speed in this tool. You can say its quite fast in understanding voice and printing text.
  • You can use your laptop inbuilt microphone for voice input or you can use external mic as well. External sound affects the application response so it is advisable to use headset mic in noisy places to get better voice to text conversion result.

How to use Google Hindi Voice Typing

google hindi voice typing

For Hindi voice typing in your laptop or PC, you can use Google online voice typing tool which is accessible from Google Docs. Lets see the whole process in steps.

  • You need internet connection and Google account.
  • Go to Google Docs
  • Login with your google login ID
  • After login into Google Docs, create a new blank document
  • A text editor window will emerge with text editing tools.
  • Now go to Tools and then Voice typing..
  • A control box will emerge on left side of document.
  • In this control box, first select the language as Hindi.
  • Now click on Microphone symbol to activate voice to text conversion.
  • Once you finish speech, click on microphone symbol again to deactivate voice to text conversion.
  • After Hindi voice typing, you can start document editing work.

Whatever you type on Google Docs can be saved directly into Google Drive or sent to email or as email attachment. You can download document also as docx, pdf, txt etc. This way you can easily create your document by dictation and later do further editing for finalization.

What is Reference Field in Drupal Content Type

Drupal system has several options to save different types of information. Drupal allows to create content type which is collection of different fields to save information. Information can be student profile, examination result, employee salary, employee leave details etc. Some of the fields in content type are basic fields like text field, number fields etc. The reference fields is also a type of field available in content type which refer to other content or user or taxonomy. It means that the information for that filed is already inserted into the system and available with some other content or user or taxonomy. You just refer that field in your content type and link that field in your content type.

drupal reference field

Lets see some examples which will help in understanding concept of reference field better.

  1. Take example of a school where all the details of students is entered into system. Each student is represents by a unique student ID in database. Now another information of result of each student need to inserted into system so create a content type of exam result. Each result relates to one of the student therefore a reference field need to be created into this “result” content type. This reference field will use “student ID” from “student profile” data. In this way results are referenced to students and a relationship is established.
  2. Assume a case of a organisation where employee details are fed into a database. Each employee is represented by a unique employee ID. There are some other details like employee salary and employee leave which need to be inserted into system so create a new content type for salary and leaves. Each of these content type will use a reference field from employee to get employee ID. This way each salary and leave is linked to concerned employee.

So reference field link information between two content type. You can take it like creating a table relationship. Whenever we create a database with multiple table, relationship between tables is also need to be created. Same thing applies to Drupal. Reference field allows you to create relationships.

How to create a new Content Type in Drupal

In my previous Drupal article, I tried to explain the Content Type in Drupal. In general, Content Type is a group of fields to create a specific form for entering the specific type of information into the Drupal system. Content Type allows user to enter different types of information in Drupal.

content type in drupal

Creating a new Content Type is not difficult but you should have understanding of different types of form fields available in Drupal. I will go into more details about different types of form fields in next article but at this time lets discuss about process of content type creation.Key steps for new Content Type in Drupal are:

Create New Content Type in Drupal

  • After login into Drupal, go to structure section and then Content Types. This is the place to create and manage fields,forms and display settings of your content
  • Now go to +Add content type
  • Now give a unique name to your new content type
  • Content type is a group of form fields for saving specific type of information into database and displaying same thing for users. So you need to enter form submission settings like Title field name, preview before submission. Title is a essential field in all content type.Similarly you can check publishing and display settings of this content type. You can select a particular menu to display this content type. Now save these settings and proceed.
  • Your content type is created with one default Text field named body. You can keep this or remove if you dont require. In this new page you will see four tabs.
    • Edit – To edit content type settings which we just created
    • Manage Fields – To add, edit, delete or change settings of form fields
    • Manage form display – To manage the display of form for this content type. All the included fields have specific display settings. You can hide a form field also.
    • Manage display – You can change the display property of field label. When you see your saved content, labels can be displayed above or inline with the field data.
  • Now you can add more fields in your content type.Go to Manage fields tab and click on +Add field.
  • You will see list of available field in the Add a new field option. Fields are broadly categorized in four type
    1. General – General fields like Boolean, date , email etc. You can also add comments as a field.
    2. Numbers – Number field like integer, float etc
    3. Text – Text fields like plain text, long text etc
    4. Reference – Reference fields are fields available in other content, taxonomy, user or other Drupal system. This is most useful way to create relationship between different parts of the system. You can link a field of other part of system and create a relationship. Just see this examples of reference field
      • ABCD is a school having profile data of all student. Each student has a unique ID. School display the result of student online. so there is one Content type “student result”. While entering result of each student, you can reference student name from the Student profile content. When you enter result, this referenced field will show the list of students.In this way the information is interlinked and a proper relationship is created.
      • In the above example, if Student unique record is saved as user, then reference field can be selected from user.
      • If result is entered into system by concerned class teacher and we expect to display display student attached in that particular class, then we may use reference user profile and get filtered class students through the view.
      • If you want that names of the city should be unique and you saved them as Taxonomy term then you can reference this Taxonomy term in user location, address etc.

I hope you would have got a general idea of creating a new content type in Drupal. Creating a new content type with general fields, number or text fields is easy. But real world examples require relationships between different information in the system so you need to create reference field. Use of reference field is quite vast which i would like to discuss in detail in next articles.

What is Virtual Studio?

Virtual Studio is quite common among Television production studios. For common man, daily TV News bulletins or discussion looks highly attractive with the decorative and colorful studio setup. Most of the people are not aware that the building or other creative structure looking behind the Anchor is all virtual. These are just created graphically. It is possible to show a News reader sitting at Taj Mahal and reading the daily bulletin. A discussion can look like as recorded in front of Eiffel tower. Nowadays, most of the News channels are using Virtual Studio for daily News bulletin and current affair discussions.

Why Virtual Studio is required?

Normally physical sets are created for recording television programmes. If some discussion program related to health need a background, then some of the pictures of related matter are printed on cloth or flex material and erected on wooden or iron structure. This is placed at the backside. It creates a background for recording video.

Disadvantage with physical sets – Several programmes are recorded in a single studio so creating a physical structure for each program is not economical as well as not feasible to erect in short interval of time.

Advantage with physical sets – If studio area can be spared for maintaining or creating a physical set for longer duration, mean it need to be disturbed daily, then physical sets may be created. Physical sets are real in nature hence they have higher depth of field. They don’t need much technology for creating background so cheap in short term. Video recordings where large recording area is used, it is a costly affair to create a Virtual Studio for sizeable area.

So Virtual Studios are normally part of News studio where multiple bulletins are there and different discussion programmes are recorded. So a small studio can also be used in different looks for each program and each look or background can be changed in minutes.

Technology involved in Virtual Studio.

Here comes the concept of video background and foreground. In general, normal studio sets are for creating background and other accessories like table, chair, Anchor are foreground of a video.

So here comes the two part of any video. First is foreground and another is the background.

Final recorded video = Foreground video + Background video.

Look at the picture shown below.

virtual studio background


virtual studio foreground


virtual studio final video


Above picture clearly shows how the foreground is superimposed on a background. Now apply same thing for video production. In a still picture, this looks quite simple but video makes it little complicated.

Here look at the foreground picture. It has a blue background that is replaced by background image for creating the final image.

When video is recorded with some single-color background like blue and background is replaced by a still image, the process is called Chroma Keying in Video production. Chroma keying is an old process where a still picture replaces the background of video.

Video is a sequence of images. It changes with time, and changes can be through different aspects of video. If there is zoom-in, then object comes closer, if there is zoom out, then object goes further in the video frame. Therefore, due to camera zoom operations, foreground object looks closer or further in the video frame. Similarly, camera position also changes the video frame so overall two parameters change the video frame. First is the zoom operation and other is the position of the camera in three-dimensional space.

In the old Chroma keying process, in spite of changes in the foreground video due to change in camera position or zoom, background images remain same and still. It clearly gives some impression like a still image pasted on a blue background.

With the development of technology, this Chroma keying process is advanced and now background image also changes in the same fashion as foreground video changes. For example, when camera zooms-in then as foreground video zooms in similarly background image (Graphics) also zooms in the same ratio. So all changes which take place for foreground video, the same changes are applied to background video ( graphics generated through computer) and then foreground and background video are mixed as Chroma keying. This creates a normal studio into Virtual studio.

Foreground video is the final output of multi camera studio setup. Background video is generated by a high end graphics machine in real time. This graphics machine receives space coordinate and zoom position of the camera continuously. The graphics video output changes in the same manner as the coordinates of camera position and zoom changes. So the correlation between foreground video and background video is maintained by a tracking mechanism. Once virtual background is superimposed on foreground video, resultant video makes a Virtual Studio a reality.

This Article is highly simplified in terms of technology so that reader may understand the concept of Virtual Studio.

Paper Jam in Printer – Care Two Things in Rainy Season

paper-jam-in-printerDuring the rainy season and humid climate condition , computer printers are mostly stuck with paper jam. This Paper Jam is a common phenomenon which occurs with most of us at some point of time. When print command is passed from computer to printer, printer print LED starts blinking .This reflects that computer communication with printer and printer acceptance to print data is going on. These things are purely electrical in nature and not affected with the weather conditions.

Weather conditions affect mechanical parts inside the printer and print papers.

Computer printers have numbers of mechanical parts which help in taking the paper inside, moving the paper through the internal route , rollers actions of printer , ejection of papers etc. Mechanical parts are affected with the weather conditions and affects results more when dealing with the delicate materials like papers.

Paper Jam – What to be done:

Heavy duty printers are coming with initial test which warms all the paper mechanism inside the printer so problems like paper jam are in bit control. But normal printers need care.

Keep check on the humidity
– This is either controlled if printer is installed in air conditioned space or separate heating arrangement is done. Sometime external heating with hanging a light lamp for some time help in removing moisture of the printer.

This has to be remembered that moist parts of printer affect for initial few prints only later the printer warms up with the initial prints so the probability of moisture related problem especially paper jam is less after certain prints.

Printing Paper – Due to weather conditions the print papers absorb moisture so the whole bunch of papers becomes sticky. Whenever any print command is given , the printer roller tries to fetch a single paper and rolls it through the internal mechanism for printing then ejects it to out tray. When print papers are moist then sometimes multiple papers are fetched inside the printer and stuck in the internal parts of printer. This is the main cause of Paper jam. Even if single paper is fetched it may not roll straight through the path and tear inside due to moist condition.

So it is necessary to keep dry papers in the paper tray. Specially during the first print, keep only single paper so as to avoid multiple paper fetch.

If your printer is stuck with paper jam , don’t try to pull the paper immediately .There are levers which release the gears of printer and paper can be pulled outside without pulling that from tightly hold conditions. So check your printer for paper release mechanism and pullout. Restart your printer to refresh any error stored in memory.

These small precautions may save your papers ,printer and precious time spent over the printing task. So avoid paper jam for your printer and save printer life.