Translation-and-Dubbing/C3/Edit-an-audio-using-Audacity/English

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Title of script: Edit an Audio in Audacity

Author: Mousumi Medhi

Keywords: video tutorial, audacity, editing, audio track, audio, convert to mp3, cut, copy, paste, delete, amplify, noise removal


Visual Cue Narration
Slide Number 1

Title Slide

Hello Everyone.

Welcome to this tutorial on Edit an Audio in Audacity.

Slide Number 2

Learning Objectives

In this tutorial, we will learn to edit an audio track in Audacity.
Slide Number 3

System Requirement

To record this tutorial I am using
  • Ubuntu Linux OS version 14.04
  • Audacity version 2.1.2
Slide Number 4

Installation

To practise this tutorial, learners should
  • Have installed Audacity on their system and
  • Have working knowledge of Audacity software

If not, for more details, refer to the Translation and Dubbing series on this website http://spoken-tutorial.org/

Show screenshot of the Timed-script I will use this timed-script for editing purpose.
Slide Number 5

Script

To practise alongside, the same script has been provided in the Code Files link of this tutorial.

Please download and use it.

Narration only Now let us open an existing Audacity project file to edit the audio.
Point out the .aup file in the desktop Earlier, we had dubbed an audio and saved it as Hindi-What-is-ST.aup on our machine.

We will open that same file here.

Double click on Hindi-What-is-ST.aup Now, go to the saved folder and double-click on Hindi-What-is-ST.aup to open the file.
Point out Hindi-What-is-ST.aup The .aup file opens up.
Point out the audio track We can see the audio track here.
Narration only Before proceeding further, it is advisable to make a copy of the project file.


In case of any major editing mistake, we can always use the original audio recording.

Click on File >> Save Project As >> Copy-Hindi-What-is-ST-edit.aup To make a copy, click on File and then on Save Project As option.

Give a suitable name.

I will give a name as Copy-Hindi-What-is-ST.aup.

Select the location.

I will choose Desktop and then click on Save.

Narration only Now, we have a copy of the original recording.
Narration only We will continue with this project file.  
Narration only First let us learn how to Zoom In and Zoom Out.
Place cursor on the audio track Place the cursor on the audio track.
Click the Zoom In and Zoom Out button on  on  the Edit Toolbar. On the Edit Toolbar click on Zoom In and Zoom Out buttons.
Point out the zoom in and out    We can see how the audio track gets zoomed in and zoomed out.
Narration only Next, let us learn how to filter out disturbing background noises.
Select a portion on the audio track with the sample noise

Point out to select a portion without voice

Select the portion on the audio track which has the noise.


Remember to select a portion without voice.

Click on Effect >> Noise Removal Now in the Main Menu, click on Effect and then on Noise Removal/Noise Reduction.
Click on Get Noise Profile Step 1:  Click on Get Noise Profile.


On doing so, the selected portion will be considered as a noise sample for further processing.

Click anywhere on the timeline Then click anywhere on the timeline to deselect the portion.
Click on Effect >> Noise Removal Once again, in the Main Menu, click on Effect and then on Noise Removal/Noise Reduction.
Choose the Noise Reduction Level Now in Step 2: Change the value in the field Noise reduction.
Narration only Use the recommended value or a lower value, that reduces the noise to an acceptable level.
Use the slider to reduce the value I will choose an appropriate value say 18.

You may also use the slider.

Narration only Higher values will remove the noise completely.


However, it will also result in distortion of the voice in the audio track.

Narration only Hisses and hums will become more prominent, as well.


Hence, choose this value carefully.

Point to Noise Radio button Make sure that, in the Noise section, Reduce/Remove radio button is selected.
Click on OK Then click on OK.
Narration only It may take some time to remove the noise, if the audio track is very long.


The process is now complete for this sample.

Click on Play button Now, let us play the recording by clicking on the Play button.


“Audio file”


The noise is now removed from the entire track.

Narration only Note: In some cases, you may have to repeat the process to further reduce the noise.


However, too much of noise reduction, may give a metallic effect to the recorded voice.  


Hence, do noise removal carefully.

Press Ctrl + S keys Let us now save the project file by pressing Ctrl + S keys.


Do so regularly as we go along.


It is advisable to save the project file whenever we have done any modification.

Narration only Let us now increase the volume of the audio segment that has been recorded at a lower volume.
Select an audio segment >> go to Effect >> Amplify Select the portion in the audio track, then go to Effect and then on Amplify.
Point out the value in the Amplification box.


We can see a value in the Amplification box.


This is the optimal amplification value for this file, recommended by Audacity.


But we can also enter another value if we want to.

Enter -10 To reduce the volume, enter negative values, say -10.
Enter 15 To increase the volume, enter positive values, say 15.
Narration only


It is advisable not to amplify the audio above the recommended value in the box.


Too much of amplification will also enhance the background noises, hisses and hums.

Use the slider >> then revert to the original value


We can also use the slider to adjust the values.


I will keep the value as 10.

Check the Allow Clipping option. Check the Allow Clipping option.


<<PAUSE>>

Click on OK Then click on OK.
Slide Number 6

Edit, Delete, Move an Audio Clip

Sometimes, an audio file contains unwanted repeats and unwanted sounds.

We can remove these by using the Cut, Copy and Paste options.

Show the audio track First, I will split this audio clip as per my Timed script timings.
Press Play button to play the audio Let me play the audio. Press the Play button in the VCR controls.
“Audio file”
Press Stop button at the end of the first sentence I have stopped at the end of the first sentence, by pressing the Stop button in the VCR controls.
Point out to split the audio I need to split the audio here.
Click on Selection Tool

Keep the cursor at the end of the 1st sentence

For that, click on the Selection Tool.

Make sure that the cursor is at the end of the first sentence.

Press Ctrl+I Now press Ctrl+I, which is the shortcut to split the audio track into separate clips.
Point out to slide the clip on the track Then, slide the next clip to the timing that we want.

I will slide it to the timing given in my Timed script.

Click on Time Shift Tool For this, click on Time Shift Tool.
Observe that the cursor is now a double-headed arrow. Observe that the cursor is now changed to double-headed arrow.
Shift the clip to this time I will shift the clip by pressing the left mouse button and dragging it to the required time.
Play the audioPress Stop button I will repeat this process once again for the next sentence.


Play the audio.


“Audio file”


I have stopped the audio by pressing the Stop button.

Click Selection Tool

Keep the cursor at the end of the 2nd sentence

I will split the audio here. For that, click on the Selection Tool.

Make sure that the cursor is at the end of the second sentence.

Press Ctrl+I Now I will press CTRL+I to split the audio.
Click on Time Shift Tool Ensure that the Time Shift Tool is selected.
Shift the clip to this time Press the left mouse button and drag it to the required time.
After narrating this sentence, pause the recording and slide all the other clips to the respective timings as given in the Timed script.  Now resume the recording. Likewise, we can split and slide the remaining segment of the audio, as per the requirement.
Show the 4 audio clips Notice that there are 4 individual audio segments, at their respective timings on the audio track.
Press Ctrl + S. Save the file before moving ahead by pressing Ctrl + S.  
Narration only Now let us learn to cut, copy and paste on the Audio Track.
Click on the Selection Tool Ensure that Selection Tool is selected.
On the Audio track click at the beginning of the third sentence


Then click on the Audio track at the beginning of the third sentence
Play the audio Play the audio.
“Audio file”
Click on Stop button I have clicked on the Stop button to stop playing the audio.
Point out the end timing of third sentence We can see that the third sentence ends here.
Point out the unwanted audio clips But it has some unwanted sounds and repetitions which we need to delete.
Select the part of the audio that needs to be deleted Select the portion of the audio that needs to be deleted, by dragging the mouse.
Press Delete Then press the Delete key on the keyboard.

Note that when you do this the remaining audio segments move forward on the audio track.

That audio clip has been removed from the audio track.

Narration only Now let us learn to move an audio clip from one place to another place on the audio track.
Select a small audio clip from the second audio segment Select the audio clip that needs to be moved.
Press Ctrl+X

Point to Edit >> Remove Audio>>Cut option.

In the Main menu, click on Edit and then click on Remove Audio or Special and then select Cut.


Or else use the keyboard shortcut Ctrl+X

Point as per narration. Note that when you do this, the remaining audio segments move forward on the audio track.


Which means it will change the timing of the remaining audio segments.


And, we need to re-arrange the timing of the remaining audio segments all over again.

Press CTRL+Z What if we don’t want to change the timings of the remaining segments?


Let me show you what to do.


First, undo the last action by pressing CTRL+Z keys.

Select the clip once again Then again select the audio clip once that needs to be removed.
Press Ctrl + Alt + X


Now, press Ctrl + Alt + X keys on your keyboard.


This will not only cut the audio segment but also keep the remaining segments in their place.

Narration only Please note the difference between the two actions.
Select small audio clip from the 1st audio segmentClick on Edit >> copy Next, select a portion of an audio segment to be copied.


I will select a portion here and click on Edit and Copy.  


Or else use the keyboard shortcut Ctrl+C.

Keep the cursor adjacent to the 3rd audio segment & click there To paste, move the cursor to the place where the audio segment needs to be placed and click there once.
Go to Edit tools panel Edit >> Paste option.


Then click on Edit and Paste.


Or else use the keyboard shortcut Ctrl+V.

Narration only Notice here - the 2 segments appear to be merged.

But it is not so.

Narration only Merge the two segments by clicking on the joint between the 2 segments.  
Narration only Now you can move the whole segment wherever you want.
Click on Zoom out option Let me zoom out here to view the whole audio segments.
Move it towards the beginning of the track. Observe that if I try to move this audio clip to the beginning of this track, I am not allowed to do so.


This is because there is no sufficient space available there to accommodate this clip.

Move the first audio clip to the end of the track.

Move the second audio clip to the beginning of the track.

Now, let us try the first audio segment.


Drag the 1st audio segment and move it to the end of the fourth audio segment.  


After creating space, we are able to move the second segment to the beginning of the track.


This is because now there is enough space available here.

Narration only So the standard rule is to first create sufficient space on the track and then move the segments.
Press CTRL + Z keys Undo the last action by pressing CTRL + Z keys.
Save the project Once all the edits are complete, save the project file once again.
Narration only Lastly, we need to Export the final project into a format suitable for playback.
Narration only Let us export this file into mp3 format.
Go to menu bar For this, go to the Main menu bar.
Click on File >> Export Click on File and then on Export.
Dialog box appears The Export file dialog box appears.  


It will ask us for a name. Enter the preferred name for this file.

Give file name “Hindi-What-is-ST" I will name the file as - Hindi-What-is-ST" .
Point out to select the location Also select the location where it has to be saved.
Choose Desktop I will choose Desktop.
Point out the formats Below this, we can see a drop-down called file type or Format.


It has various audio formats like .wav .mp3, .ogg, etc.

Choose MP3 as a format I will choose MP3 files as the format.
Click on Save Then click on Save.
Narration only Next we will get a dialog called Edit Metadata.


Here, we can add the Artist Name and other information as per our requirement.


I will leave these fields blank.

Click on OK Click on OK.

This will save the output as Hindi-What-is-ST.mp3 file.


This may take some time to complete.

Switch to the Desktop >> Play the file using VLC player Now, go to the folder where we saved the file.


Here is the .mp3 file which we exported.


Let us play this file using any standard audio player.

“Audio file”
Slide Number 7

Summary

This brings us to the end of the tutorial.


Let me summarize the tutorial. In this tutorial we have learnt how to-

  • Open an existing .aup project file
  • Zoom in and out on the audio track
  • Filter background noise
  • Amplify the audio
  • Cut, copy, paste, delete, move an audio clip
  • Merge two audio clips
  • Save and export the audio into .mp3 format.
Slide Number 8

Assignment

As an assignment, edit an audio file using the timed-script.
Slide Number 9a

About Spoken Tutorial project


The video at the following link summarises the Spoken Tutorial project.

Please download and watch it.

Slide Number 9b

Spoken Tutorial workshops


The Spoken Tutorial Project Team:
  • conducts workshops and
  • gives certificates

For more details, please write to us.

Slide Number 10

Forum for specific questions

Please post your timed queries in this forum.
Slide Number 11

Acknowledgement

Spoken Tutorial Project is funded by the NMEICT, MHRD, Government of India.

More information on this Mission is available at this link.

Previous slide This script has been contributed by the Spoken Tutorial Team.

And this is Mousumi Medhi from IIT Bombay signing off.

Thanks for joining.

Contributors and Content Editors

Mousumi, Nancyvarkey