NCERT Textbook: Creating Audio-Video Communication | Information Technology for Class 9 PDF Download

 Page 1


In the last chapter, we learnt how to create still images 
and enhance them, now it will be interesting to see how 
to create audio and video resources.
The use of more than one medium of expression or 
communication is called multimedia. Multimedia uses 
a combination of text, audio, images, animation, videos 
and interactives. This is different from traditional forms 
of printed or hand produced material.
Content means something that can be expressed 
through some media like speech, writing or any other 
form of art.
Students in a class are discussing about the activity 
they have performed on purification of water .
Neer: Why is this activity necessary?
Nancy: What is the use of this activity?
Raima joins the school after a long gap. She is surrounded 
by her friends, everyone is curious to know the reason 
for her long absence from the school.
Neer: Raima, you were always very regular in attending 
school, why were you absent for a week?
Raima: I was suffering from diarrhoea and fever.
Nancy: Oh! What did the doctor say?
Interactives 
mean a two-way 
communication 
where the user 
interacts with the 
content and gets 
feedback.
List of waterborne 
diseases 
• Diarrhoea
• Dysentery
• Typhoid Fever
• Cholera
• Hepatitis A
• Jaundice etc
Creating Audio 
Video Communication
Chapter
4
Chapter 4.indd   57 7/16/2020   2:45:40 PM
2024-25
Page 2


In the last chapter, we learnt how to create still images 
and enhance them, now it will be interesting to see how 
to create audio and video resources.
The use of more than one medium of expression or 
communication is called multimedia. Multimedia uses 
a combination of text, audio, images, animation, videos 
and interactives. This is different from traditional forms 
of printed or hand produced material.
Content means something that can be expressed 
through some media like speech, writing or any other 
form of art.
Students in a class are discussing about the activity 
they have performed on purification of water .
Neer: Why is this activity necessary?
Nancy: What is the use of this activity?
Raima joins the school after a long gap. She is surrounded 
by her friends, everyone is curious to know the reason 
for her long absence from the school.
Neer: Raima, you were always very regular in attending 
school, why were you absent for a week?
Raima: I was suffering from diarrhoea and fever.
Nancy: Oh! What did the doctor say?
Interactives 
mean a two-way 
communication 
where the user 
interacts with the 
content and gets 
feedback.
List of waterborne 
diseases 
• Diarrhoea
• Dysentery
• Typhoid Fever
• Cholera
• Hepatitis A
• Jaundice etc
Creating Audio 
Video Communication
Chapter
4
Chapter 4.indd   57 7/16/2020   2:45:40 PM
2024-25
ICT Tex Tbook — Class Ix 58
Raima: The doctor said it was due to drinking 
contaminated water. The doctor also told me that 
many people are dying because of water pollution and 
waterborne diseases every year. 
Neer: Oh, it is a very serious issue. 
Nancy: You know Raima, yesterday only, we did an 
activity on water purification.
Raima: Oh! It is good that you performed such a relevant 
activity. Can you explain me what you learnt.
Neer and Nancy explained all the activities they 
performed yesterday.
Raima: Had I performed the activity myself, I would 
have learnt better by performing the activity. 
Neer: Let us do something, so that you may not miss 
out the learning.
Nancy: Specially this water purification activity is very 
useful for everyone.
Neer: We can create posters to generate awareness on 
the importance of water purification.
Raima: Let us make something which can be more 
impactful and interesting than a printed material.
Activity 1
Imagine yourself as a part of this activity, what media will 
you use to explain this?
Nancy: Can we record an audio?
Raima: It is similar to what you explained to me but I 
did not understand it. I think we need to demonstrate 
the process.
Neer: So, you want us to do the activity all over again. 
Raima: Yes, and this time we will record it. We will also 
add posters, text, images, audios and may be some 
more materials and create a small video film.
Nancy: Yes, it will help us understand the concept better 
and we can also share it with others.
Neer: What all do we need to do for making this video film?
Chapter 4.indd   58 27-Feb-19   4:47:23 PM
2024-25
Page 3


In the last chapter, we learnt how to create still images 
and enhance them, now it will be interesting to see how 
to create audio and video resources.
The use of more than one medium of expression or 
communication is called multimedia. Multimedia uses 
a combination of text, audio, images, animation, videos 
and interactives. This is different from traditional forms 
of printed or hand produced material.
Content means something that can be expressed 
through some media like speech, writing or any other 
form of art.
Students in a class are discussing about the activity 
they have performed on purification of water .
Neer: Why is this activity necessary?
Nancy: What is the use of this activity?
Raima joins the school after a long gap. She is surrounded 
by her friends, everyone is curious to know the reason 
for her long absence from the school.
Neer: Raima, you were always very regular in attending 
school, why were you absent for a week?
Raima: I was suffering from diarrhoea and fever.
Nancy: Oh! What did the doctor say?
Interactives 
mean a two-way 
communication 
where the user 
interacts with the 
content and gets 
feedback.
List of waterborne 
diseases 
• Diarrhoea
• Dysentery
• Typhoid Fever
• Cholera
• Hepatitis A
• Jaundice etc
Creating Audio 
Video Communication
Chapter
4
Chapter 4.indd   57 7/16/2020   2:45:40 PM
2024-25
ICT Tex Tbook — Class Ix 58
Raima: The doctor said it was due to drinking 
contaminated water. The doctor also told me that 
many people are dying because of water pollution and 
waterborne diseases every year. 
Neer: Oh, it is a very serious issue. 
Nancy: You know Raima, yesterday only, we did an 
activity on water purification.
Raima: Oh! It is good that you performed such a relevant 
activity. Can you explain me what you learnt.
Neer and Nancy explained all the activities they 
performed yesterday.
Raima: Had I performed the activity myself, I would 
have learnt better by performing the activity. 
Neer: Let us do something, so that you may not miss 
out the learning.
Nancy: Specially this water purification activity is very 
useful for everyone.
Neer: We can create posters to generate awareness on 
the importance of water purification.
Raima: Let us make something which can be more 
impactful and interesting than a printed material.
Activity 1
Imagine yourself as a part of this activity, what media will 
you use to explain this?
Nancy: Can we record an audio?
Raima: It is similar to what you explained to me but I 
did not understand it. I think we need to demonstrate 
the process.
Neer: So, you want us to do the activity all over again. 
Raima: Yes, and this time we will record it. We will also 
add posters, text, images, audios and may be some 
more materials and create a small video film.
Nancy: Yes, it will help us understand the concept better 
and we can also share it with others.
Neer: What all do we need to do for making this video film?
Chapter 4.indd   58 27-Feb-19   4:47:23 PM
2024-25
Creating a udio -V ideo Communi Cation 59
Raima: We already have a topic, the title of our video 
film will be ‘Waterborne diseases and their prevention.’
Activity 2
Think about what content should be included to make a 
video film on Water Pollution.
Nancy: So we need to have information on water pollution, 
causes of water pollution, effects of water pollution, 
waterborne diseases and methods of purification of 
contaminated water.
Raima: So first of all, we had to collect all relevant 
information to make this video film, we also need to 
know sources of information.
Neer: We can use books in the library to collect 
information about Water Pollution and its effects and 
present it through images and audio narration. 
Nancy: We can talk to a doctor to learn more about 
waterborne diseases and then present it through text 
and audio narration. 
Raima: We will request our science teachers to help us 
in identifying more activities for water purification. We 
will record a video of water purifying techniques.
Nancy: So now we have to decide who will do what.
Raima: I can go to the doctor and collect more information 
on waterborne diseases.
Neer and Nancy: Raima can learn more water purifying 
techniques form the science teacher then we will record 
a video on the techniques of purifying water.
Nancy: I can search information from the library. 
The students have collected all the information in the 
form of text and images. They have also recorded a video 
showing the techniques of water purification.
Neer: Now we have to write the audio script based on 
the information we have collected from various sources. 
Raima: But how are we going to record an audio?
Neer: Let's record it in the evening through my mom's smartphone.
Chapter 4.indd   59 27-Feb-19   4:47:23 PM
2024-25
Page 4


In the last chapter, we learnt how to create still images 
and enhance them, now it will be interesting to see how 
to create audio and video resources.
The use of more than one medium of expression or 
communication is called multimedia. Multimedia uses 
a combination of text, audio, images, animation, videos 
and interactives. This is different from traditional forms 
of printed or hand produced material.
Content means something that can be expressed 
through some media like speech, writing or any other 
form of art.
Students in a class are discussing about the activity 
they have performed on purification of water .
Neer: Why is this activity necessary?
Nancy: What is the use of this activity?
Raima joins the school after a long gap. She is surrounded 
by her friends, everyone is curious to know the reason 
for her long absence from the school.
Neer: Raima, you were always very regular in attending 
school, why were you absent for a week?
Raima: I was suffering from diarrhoea and fever.
Nancy: Oh! What did the doctor say?
Interactives 
mean a two-way 
communication 
where the user 
interacts with the 
content and gets 
feedback.
List of waterborne 
diseases 
• Diarrhoea
• Dysentery
• Typhoid Fever
• Cholera
• Hepatitis A
• Jaundice etc
Creating Audio 
Video Communication
Chapter
4
Chapter 4.indd   57 7/16/2020   2:45:40 PM
2024-25
ICT Tex Tbook — Class Ix 58
Raima: The doctor said it was due to drinking 
contaminated water. The doctor also told me that 
many people are dying because of water pollution and 
waterborne diseases every year. 
Neer: Oh, it is a very serious issue. 
Nancy: You know Raima, yesterday only, we did an 
activity on water purification.
Raima: Oh! It is good that you performed such a relevant 
activity. Can you explain me what you learnt.
Neer and Nancy explained all the activities they 
performed yesterday.
Raima: Had I performed the activity myself, I would 
have learnt better by performing the activity. 
Neer: Let us do something, so that you may not miss 
out the learning.
Nancy: Specially this water purification activity is very 
useful for everyone.
Neer: We can create posters to generate awareness on 
the importance of water purification.
Raima: Let us make something which can be more 
impactful and interesting than a printed material.
Activity 1
Imagine yourself as a part of this activity, what media will 
you use to explain this?
Nancy: Can we record an audio?
Raima: It is similar to what you explained to me but I 
did not understand it. I think we need to demonstrate 
the process.
Neer: So, you want us to do the activity all over again. 
Raima: Yes, and this time we will record it. We will also 
add posters, text, images, audios and may be some 
more materials and create a small video film.
Nancy: Yes, it will help us understand the concept better 
and we can also share it with others.
Neer: What all do we need to do for making this video film?
Chapter 4.indd   58 27-Feb-19   4:47:23 PM
2024-25
Creating a udio -V ideo Communi Cation 59
Raima: We already have a topic, the title of our video 
film will be ‘Waterborne diseases and their prevention.’
Activity 2
Think about what content should be included to make a 
video film on Water Pollution.
Nancy: So we need to have information on water pollution, 
causes of water pollution, effects of water pollution, 
waterborne diseases and methods of purification of 
contaminated water.
Raima: So first of all, we had to collect all relevant 
information to make this video film, we also need to 
know sources of information.
Neer: We can use books in the library to collect 
information about Water Pollution and its effects and 
present it through images and audio narration. 
Nancy: We can talk to a doctor to learn more about 
waterborne diseases and then present it through text 
and audio narration. 
Raima: We will request our science teachers to help us 
in identifying more activities for water purification. We 
will record a video of water purifying techniques.
Nancy: So now we have to decide who will do what.
Raima: I can go to the doctor and collect more information 
on waterborne diseases.
Neer and Nancy: Raima can learn more water purifying 
techniques form the science teacher then we will record 
a video on the techniques of purifying water.
Nancy: I can search information from the library. 
The students have collected all the information in the 
form of text and images. They have also recorded a video 
showing the techniques of water purification.
Neer: Now we have to write the audio script based on 
the information we have collected from various sources. 
Raima: But how are we going to record an audio?
Neer: Let's record it in the evening through my mom's smartphone.
Chapter 4.indd   59 27-Feb-19   4:47:23 PM
2024-25
ICT Tex Tbook — Class Ix 60
In the evening, they all gathered at Neer's house to record 
the narration. But while playing back they noticed some 
disturbance in the audio. 
Nancy: How to remove this disturbance from the audio? 
Raima: We can use software to edit the audio narration. 
So, let’s first get familiar with the Audacity interface. 
(Refer Fig. 4.1).
Fig. 4.1 : Audacity Interface
Let’s begin with Audacity and Record Narration.
1. Go to file and click “New”. A new window will appear 
(Refer Fig. 4.2).
Raima: Let us start creating our audio resource.
Fig. 4.2 : Getting started
How to record an 
audio?
There are two types 
of recording devices: 
analog and digital. 
It has its own merits 
and demerits and 
they may be used as 
per need of the task. 
List of recording 
devices
• Mini Disc 
Recorder
• DAT Recorder
• Desktop and 
headphone
• Laptop Audio 
Interface
• Smartphone
List of audio tools
• Audacity
• Mixxx
• Ardour
Audacity
• Audacity is a free 
open source digital 
audio   editor to 
record computer  
software 
application, 
available for 
Windows, macOS/
OS X, Linux and 
other operating      
systems.
• Interestingly, you 
do not need sound 
mixer or any other 
Chapter 4.indd   60 27-Feb-19   4:47:24 PM
2024-25
Page 5


In the last chapter, we learnt how to create still images 
and enhance them, now it will be interesting to see how 
to create audio and video resources.
The use of more than one medium of expression or 
communication is called multimedia. Multimedia uses 
a combination of text, audio, images, animation, videos 
and interactives. This is different from traditional forms 
of printed or hand produced material.
Content means something that can be expressed 
through some media like speech, writing or any other 
form of art.
Students in a class are discussing about the activity 
they have performed on purification of water .
Neer: Why is this activity necessary?
Nancy: What is the use of this activity?
Raima joins the school after a long gap. She is surrounded 
by her friends, everyone is curious to know the reason 
for her long absence from the school.
Neer: Raima, you were always very regular in attending 
school, why were you absent for a week?
Raima: I was suffering from diarrhoea and fever.
Nancy: Oh! What did the doctor say?
Interactives 
mean a two-way 
communication 
where the user 
interacts with the 
content and gets 
feedback.
List of waterborne 
diseases 
• Diarrhoea
• Dysentery
• Typhoid Fever
• Cholera
• Hepatitis A
• Jaundice etc
Creating Audio 
Video Communication
Chapter
4
Chapter 4.indd   57 7/16/2020   2:45:40 PM
2024-25
ICT Tex Tbook — Class Ix 58
Raima: The doctor said it was due to drinking 
contaminated water. The doctor also told me that 
many people are dying because of water pollution and 
waterborne diseases every year. 
Neer: Oh, it is a very serious issue. 
Nancy: You know Raima, yesterday only, we did an 
activity on water purification.
Raima: Oh! It is good that you performed such a relevant 
activity. Can you explain me what you learnt.
Neer and Nancy explained all the activities they 
performed yesterday.
Raima: Had I performed the activity myself, I would 
have learnt better by performing the activity. 
Neer: Let us do something, so that you may not miss 
out the learning.
Nancy: Specially this water purification activity is very 
useful for everyone.
Neer: We can create posters to generate awareness on 
the importance of water purification.
Raima: Let us make something which can be more 
impactful and interesting than a printed material.
Activity 1
Imagine yourself as a part of this activity, what media will 
you use to explain this?
Nancy: Can we record an audio?
Raima: It is similar to what you explained to me but I 
did not understand it. I think we need to demonstrate 
the process.
Neer: So, you want us to do the activity all over again. 
Raima: Yes, and this time we will record it. We will also 
add posters, text, images, audios and may be some 
more materials and create a small video film.
Nancy: Yes, it will help us understand the concept better 
and we can also share it with others.
Neer: What all do we need to do for making this video film?
Chapter 4.indd   58 27-Feb-19   4:47:23 PM
2024-25
Creating a udio -V ideo Communi Cation 59
Raima: We already have a topic, the title of our video 
film will be ‘Waterborne diseases and their prevention.’
Activity 2
Think about what content should be included to make a 
video film on Water Pollution.
Nancy: So we need to have information on water pollution, 
causes of water pollution, effects of water pollution, 
waterborne diseases and methods of purification of 
contaminated water.
Raima: So first of all, we had to collect all relevant 
information to make this video film, we also need to 
know sources of information.
Neer: We can use books in the library to collect 
information about Water Pollution and its effects and 
present it through images and audio narration. 
Nancy: We can talk to a doctor to learn more about 
waterborne diseases and then present it through text 
and audio narration. 
Raima: We will request our science teachers to help us 
in identifying more activities for water purification. We 
will record a video of water purifying techniques.
Nancy: So now we have to decide who will do what.
Raima: I can go to the doctor and collect more information 
on waterborne diseases.
Neer and Nancy: Raima can learn more water purifying 
techniques form the science teacher then we will record 
a video on the techniques of purifying water.
Nancy: I can search information from the library. 
The students have collected all the information in the 
form of text and images. They have also recorded a video 
showing the techniques of water purification.
Neer: Now we have to write the audio script based on 
the information we have collected from various sources. 
Raima: But how are we going to record an audio?
Neer: Let's record it in the evening through my mom's smartphone.
Chapter 4.indd   59 27-Feb-19   4:47:23 PM
2024-25
ICT Tex Tbook — Class Ix 60
In the evening, they all gathered at Neer's house to record 
the narration. But while playing back they noticed some 
disturbance in the audio. 
Nancy: How to remove this disturbance from the audio? 
Raima: We can use software to edit the audio narration. 
So, let’s first get familiar with the Audacity interface. 
(Refer Fig. 4.1).
Fig. 4.1 : Audacity Interface
Let’s begin with Audacity and Record Narration.
1. Go to file and click “New”. A new window will appear 
(Refer Fig. 4.2).
Raima: Let us start creating our audio resource.
Fig. 4.2 : Getting started
How to record an 
audio?
There are two types 
of recording devices: 
analog and digital. 
It has its own merits 
and demerits and 
they may be used as 
per need of the task. 
List of recording 
devices
• Mini Disc 
Recorder
• DAT Recorder
• Desktop and 
headphone
• Laptop Audio 
Interface
• Smartphone
List of audio tools
• Audacity
• Mixxx
• Ardour
Audacity
• Audacity is a free 
open source digital 
audio   editor to 
record computer  
software 
application, 
available for 
Windows, macOS/
OS X, Linux and 
other operating      
systems.
• Interestingly, you 
do not need sound 
mixer or any other 
Chapter 4.indd   60 27-Feb-19   4:47:24 PM
2024-25
Creating a udio -V ideo Communi Cation 61
sophisticated 
device to use it.
Using Audacity you 
can
1.  record by default 
microphone 
or by external 
microphone.
2.  edit, import and 
export audio files.
3.  mix tracks by 
using envelop.
4.  create effects and 
even increase 
amplitude.
5. use multiple 
tracks.
Raima: Let us add a new track (Refer Fig. 4.3).
Fig. 4.3 : Adding a new track
A new track will appear in which you can record your 
voice or sound using either default microphone or the 
external microphone. Ensure that proper silence is 
maintained while recording. To start the recording click 
on the Red recording button (Fig. 4.4) and speak. To 
finish recording, press the Stop button or the Space Bar 
on your computer. You can insert more tracks in a 
similar fashion.
Fig 4.4 : Recording an audio
Chapter 4.indd   61 27-Feb-19   4:47:25 PM
2024-25