Audacity/C3/Edit-an-audio-using-Audacity/English-timed

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Time Narration
00:01 Hello Everyone.

Welcome to this tutorial on Edit an Audio in Audacity.

00:07 In this tutorial, we will learn to edit an audio track in Audacity.
00:14 To record this tutorial I am using

Ubuntu Linux OS version 14.04 , Audacity version 2.1.2

00:25 To practise this tutorial, learners should

Have installed Audacity on their system and

00:32 Have working knowledge of Audacity software
00:36 If not, for more details, refer to the Translation and Dubbing series on this website
00:43 I will use this timed-script for editing purpose.
00:48 To practise alongside, the same script has been provided in the Code Files link of this tutorial.

Please download and use it.

00:58 Now let us open an existing Audacity project file to edit the audio.
01:04 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.

01:16 Now, go to the saved folder and double-click on Hindi-What-is-ST.aup to open the file.
01:25 The .aup file opens up.
01:28 We can see the audio track here.
01:32 Before proceeding further, it is advisable to make a copy of the project file.
01:38 In case of any major editing mistake, we can always use the original audio recording.
01:45 To make a copy, click on File and then on Save Project As option.

Give a suitable name.

01:55 I will give a name as Copy-Hindi-What-is-ST.aup.
02:02 Select the location.

I will choose Desktop and then click on Save.

02:09 Now, we have a copy of the original recording.
02:13 We will continue with this project file.
02:17 First let us learn how to Zoom In and Zoom Out.
02:22 Place the cursor on the audio track.
02:25 On the Edit Toolbar click on Zoom In and Zoom Out buttons.
02:32 We can see how the audio track gets zoomed in and zoomed out.
02:39 Next, let us learn how to filter out disturbing background noises.
02:45 Select the portion on the audio track which has the noise.

Remember to select a portion without voice.

02:54 Now in the Main Menu, click on Effect and then on Noise Removal/Noise Reduction.
03:03 Step 1: Click on Get Noise Profile.

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

03:15 Then click anywhere on the timeline to deselect the portion.
03:20 Once again, in the Main Menu, click on Effect and then on Noise Removal/Noise Reduction.
03:28 Now in Step 2: Change the value in the field Noise reduction.
03:35 Use the recommended value or a lower value, that reduces the noise to an acceptable level.
03:42 I will choose an appropriate value say 18.

You may also use the slider.

03:50 Higher values will remove the noise completely.
03:54 However, it will also result in distortion of the voice in the audio track.
04:00 Hisses and hums will become more prominent, as well.

Hence, choose this value carefully.

04:07 Make sure that, in the Noise section, Reduce/Remove radio button is selected.
04:14 Then click on OK.
04:17 It may take some time to remove the noise, if the audio track is very long.

The process is now complete for this sample.

04:26 Now, let us play the recording by clicking on the Play button.
Add the audio
04:37 The noise is now removed from the entire track.
04:41 Note: In some cases, you may have to repeat the process to further reduce the noise.
04:48 However, too much of noise reduction, may give a metallic effect to the recorded voice.

Hence, do noise removal carefully.

04:59 Let us now save the project file by pressing Ctrl + S keys.
05:05 Do so regularly as we go along.
05:08 It is advisable to save the project file whenever we have done any modification.
05:15 Let us now increase the volume of the audio segment that has been recorded at a lower volume.
05:22 Select the portion in the audio track, then go to Effect and then on Amplify.
05:30 We can see a value in the Amplification box.
05:34 This is the optimal amplification value for this file, recommended by Audacity.

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

05:45 To reduce the volume, enter negative values, say -10.
05:51 To increase the volume, enter positive values, say 15.
05:57 It is advisable not to amplify the audio above the recommended value in the box.
06:03 Too much of amplification will also enhance the background noises, hisses and hums.
06:10 We can also use the slider to adjust the values.

I will keep the value as 10.

06:18 Check the Allow Clipping option.
06:21 Then click on OK.
06:24 Sometimes, an audio file contains unwanted repeats and unwanted sounds.
06:30 We can remove these by using the Cut, Copy and Paste options.
06:36 First, I will split this audio clip as per my Timed script timings.
06:41 Let me play the audio. Press the Play button in the VCR controls.
Add the audio
06:53 I have stopped at the end of the first sentence, by pressing the Stop button in the VCR controls.
07:00 I need to split the audio here.
07:03 For that, click on the Selection Tool.

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

07:11 Now press Ctrl+I, which is the shortcut to split the audio track into separate clips.
07:18 Then, slide the next clip to the timing that we want.
07:23 I will slide it to the timing given in my Timed script.
07:27 For this, click on Time Shift Tool.
07:30 Observe that the cursor is now changed to double-headed arrow.
07:35 I will shift the clip by pressing the left mouse button and dragging it to the required time.
07:43 I will repeat this process once again for the next sentence.

Play the audio.

Add tha audio
07:55 I have stopped the audio by pressing the Stop button.
07:59 I will split the audio here. For that, click on the Selection Tool.
08:06 Make sure that the cursor is at the end of the second sentence.
08:11 Now I will press CTRL+I to split the audio.
08:16 Ensure that the Time Shift Tool is selected.
08:20 Press the left mouse button and drag it to the required time.
08:25 Likewise, we can split and slide the remaining segment of the audio, as per the requirement.
08:32 Notice that there are 4 individual audio segments, at their respective timings on the audio track.
08:40 Save the file before moving ahead by pressing Ctrl + S.
08:45 Now let us learn to cut, copy and paste on the Audio Track.
08:51 Ensure that Selection Tool is selected.
08:55 Then click on the Audio track at the beginning of the third sentence
09:00 Play the audio.
Add the Audio file
09:11 I have clicked on the Stop button to stop playing the audio.
09:16 We can see that the third sentence ends here.
09:20 But it has some unwanted sounds and repetitions which we need to delete.
09:26 Select the portion of the audio that needs to be deleted, by dragging the mouse.
09:33 Then press the Delete key on the keyboard.
09:37 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.

09:48 Now let us learn to move an audio clip from one place to another place on the audio track.
09:55 Select the audio clip that needs to be moved.
09:59 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

10:14 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.

10:26 And, we need to re-arrange the timing of the remaining audio segments all over again.
10:33 What if we don’t want to change the timings of the remaining segments?

Let me show you what to do.

10:41 First, undo the last action by pressing CTRL+Z keys.
10:47 Then again select the audio clip once that needs to be removed.
10:52 Now, press Ctrl + Alt + X keys on your keyboard.
10:58 This will not only cut the audio segment but also keep the remaining segments in their place.
11:05 Please note the difference between the two actions.
11:09 Next, select a portion of an audio segment to be copied.
11:14 I will select a portion here and click on Edit and Copy.

Or else use the keyboard shortcut Ctrl+C.

11:25 To paste, move the cursor to the place where the audio segment needs to be placed and click there once.
11:33 Then click on Edit and Paste.

Or else use the keyboard shortcut Ctrl+V.

11:43 Notice here - the 2 segments appear to be merged.

But it is not so.

11:49 Merge the two segments by clicking on the joint between the 2 segments.
11:54 Now you can move the whole segment wherever you want.
11:59 Let me zoom out here to view the whole audio segments.
12:04 Observe that if I try to move this audio clip to the beginning of this track, I am not allowed to do so.
12:12 This is because there is no sufficient space available there to accommodate this clip.
12:18 Now, let us try the first audio segment.
12:22 Drag the 1st audio segment and move it to the end of the fourth audio segment.
12:28 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.

12:40 So the standard rule is to first create sufficient space on the track and then move the segments.
12:48 Undo the last action by pressing CTRL + Z keys.
12:53 Once all the edits are complete, save the project file once again.
12:58 Lastly, we need to Export the final project into a format suitable for playback.
13:05 Let us export this file into mp3 format.
13:09 For this, go to the Main menu bar. Click on File and then on Export.
13:15 The Export file dialog box appears.

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

13:26 I will name the file as Hindi-What-is-ST.
13:30 Also select the location where it has to be saved.

I will choose Desktop.

13:37 Below this, we can see a drop-down called file type or Format.
13:43 It has various audio formats like wav, mp3, ogg, etc.
13:52 I will choose MP3 files as the format.
13:57 Then click on Save.
14:00 Next we will get a dialog called Edit Metadata.
04:05 Here, we can add the Artist Name and other information as per our requirement.

I will leave these fields blank.

14:15 Click on OK.

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

14:22 This may take some time to complete.
14:25 Now, go to the folder where we saved the file.

Here is the mp3 file which we exported.

14:32 Let us play this file using any standard audio player.
Add the Audio file
14:49 This brings us to the end of the tutorial.
14:52 Let me summarize the tutorial.
14:55 In this tutorial we have learnt how to-

Open an existing dot aup project file

15:03 Zoom in and out on the audio track

Filter background noise

15:09 Amplify the audio

Cut, copy, paste, delete, move an audio clip

15:17 Merge two audio clips

Save and export the audio into .mp3 format.

15:25 As an assignment, edit an audio file using the timed-script.
15:31 The video at the following link summarises the Spoken Tutorial project.

Please download and watch it.

15:39 The Spoken Tutorial Project Team: conducts workshops and gives certificates

For more details, please write to us.

15:49 Please post your timed queries in this forum.
15:53 Spoken Tutorial Project is supported by the NMEICT, MHRD, Government of India.

More information on this Mission is available at this link.

16:05 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

PoojaMoolya