Project Documentation - B7

From SoftwarePractice.org

Contents 1 Digital Music Sample - The Team 2 Analysis of The Project 2.1 User Interface 2.2 Recorder 2.3 Trimmer 2.4 Audio player 3 System Inputs And Outputs 4 Stakeholders 5 Usage Scenarios 6 Use Cases 6.1 Playing keyboard using Mouse 6.2 Recording 6.3 Changing the Pitch 6.4 Trimming 7 Class Diagrams 8 Function List 9 Sequence Diagrams 10 Pre And Post Conditions 10.1 MainApp 10.2 SynthUI 10.3 Keyboard 10.4 SynthController 10.5 Key 10.6 MidiNote 10.7 AudioPlayer 10.8 Recorder 10.9 MidiPlayer 10.10 Trimmer 11 Test Cases 11.1 Changing the Pitch Test 11.2 Recording Test 11.3 Playing wav files Test 11.4 Rapidly playing keys Test 11.5 Trimming Test 12 Screenshots 13 Reference 14 Instructor comments

Digital Music Sample - The Team

The project we are to be working over the semester will be the Digital Music Sampler.

Our Team is B7 and consists of Gordon Wong, Jeffrey Scarra, Atttaporn Phuangpee, Van Nguyen

We will be following the Minniture Unified Process (MUP) we created, in order to finish our Digital Music Sampler project.

Analysis of The Project

The Digital Music Sampler is a system that digitally records an audio file from a musical instrument or any other sound source. The system then allows the user to play back previously recorded sounds via an electronic (piano-like) keyboard User interface. The main system can be divided into 4 parts:

User Interface

The graphical user interface (GUI) is the interface between the user and the sampler. The GUI uses graphical images and texts to represent any information's and actions that available to the user. For the project, GUI would include some important control interfaces such as volume, octave, pith, record, playback, and piano-like keyboard.

Recorder

The functionality of the recorder is to record and store sounds from inputs such as from a microphone. The user would be able to record sounds and save them as a wave file. Then the system would allow the user to assign each file to the key on the keyboard as they wish. Additionally, the user could access the files at any times, if they could modify by the user, for example, trimming, or deleting.

Trimmer

Trimming is a function that lets the user remove parts of a particular audio file (i.e. silence before and after the recorded 'voice'). Having this option would add a further level of control to the user, in terms of managing the storage size of the file, and provide a more desirable output.

Audio player

Now that the system could record the sound, it would not be as useful, if you could not monitor it. The Audio Player is the class that stores the locations of the recorded 'voices'. This class is called upon when the user plays a key that is no longer set as a particular wave file, it is the job of this class to find that wave file and output the sound.

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System Inputs And Outputs

The system inputs would be a recorded sound, which records through a sound card of the computer using a microphone. The recorded sound will keep as a .wav file on the local folder of the computer, this will enable user to assign each files accordingly to the key of keyboard. Furthermore, the system will allow user to edit the file such as trimming, adding, or deleting a particularly sound file. The output of the system will be an audio sound that plays back by the sound card.

User Inputs	System Outputs
Clicks Mouse on Key	Plays corresponding sound
Presses 'q' on keyboard	Plays Corresponding sound
Presses 'w' on keyboard	Plays Corresponding sound
Presses 'e' on keyboard	Plays Corresponding sound
Presses 'r' on keyboard	Plays Corresponding sound
Presses 't' on keyboard	Plays Corresponding sound
Presses 'y' on keyboard	Plays Corresponding sound
Presses 'u' on keyboard	Plays Corresponding sound
Presses 'c' on keyboard	Plays Corresponding sound
Presses 'a' on keyboard	Plays Corresponding sound
Presses 's' on keyboard	Plays Corresponding sound
Presses 'd' on keyboard	Plays Corresponding sound
Presses 'f' on keyboard	Plays Corresponding sound
Presses 'g' on keyboard	Plays Corresponding sound
Presses 'h' on keyboard	Plays Corresponding sound
Presses 'i' on keyboard	Plays Corresponding sound
Presses '1' on keyboard	Plays Corresponding sound
Presses '2' on keyboard	Plays Corresponding sound
Presses '3' on keyboard	Plays Corresponding sound
Presses '4' on keyboard	Plays Corresponding sound
Presses '5' on keyboard	Plays Corresponding sound
Presses '6' on keyboard	Plays Corresponding sound
Presses '7' on keyboard	Plays Corresponding sound
Presses '8' on keyboard	Plays Corresponding sound
Presses '9' on keyboard	Plays Corresponding sound
Presses '0' on keyboard	Plays Corresponding sound
Move "Pitch Slider" to +0.5	Increase the tone by 0.5
Move "Pitch Slider" to +1	Increase the tone by 1
Move "Pitch Slider" to -0.5	Decrease the tone by 0.5
Move "Pitch Slider" to -1	Decrease the tone by 0.5
Move Octave Slider up or down	Moves the position of the key according to the keyboard
Move Volume up or down	Increase or decrease the sound
Click Mute	Moves the volume bar to 0

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Stakeholders

The highlighted Stakeholders are:

1. Developer - Initial design, implementing the program, writing documentation, testing.

2. User - operating, using, and assisting Developer for the design of system.

3. Musician - correcting sound, quality control.

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Usage Scenarios

Scenario 1

• Paul wants to play the keyboard, whilst constantly changing the pitch.

Scenario 2

• Sarah wishes to record and save her guitar notes, so that Paul can play it on the keyboard later.

Scenario 3

• Paul wants to play, using Sarah's previous guitar "voices"

Scenario 4

• Paul expects the keyboard notes to be a 'natural sound', that is so the sound of multiple notes can overlap each other.

Scenario 5

• Sarah wants to trim the sound to remove the silence from the start and end of the recorded sound.

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Use Cases

The Use Cases are listed below, which explains how the users ("Actor") should interact with the system:

Playing keyboard using Mouse

User	System
1. Opens Program
	2. Loads GUI with default settings
3. Clicks interface with mouse on key
	4. Plays note through speakers as clicked
5. Clicks interface with mouse on key, again
	6. Repeat Steps 5 & 6 until finished playing
7. User Clicks Exit
	8. Program Quits

Recording

User	System
1. Chooses Record Interface
	2. Loads Recorder window
3. Clicks Record
	4. Creates new wave file
5. User plays the sound into the mic 6. User Clicks Stop
	7. Saves 'voice' to created wave file 8. Displays save file name

Changing the Pitch

User	System
1. Opens Program 2. Plays Keys using keyboard
	3. Plays corresponding Sound
4. Changes the Pitch to -1 using the Slider
	5. Adjusts Pitch to -1
6. Plays Same note again
	7. Plays corresponding sound with new pitch
8. Clicks Default Button
	9. Returns Pitch to default value
10. Clicks Exit
	11. Program Closes

Trimming

User	System
1. Opens Trimmer mode
	2. Loads Trimmer Interface
3. Opens 'voice'
	4. Load 'voice' into trimmer
5. Edits and saves the 'voice'
	6. Edits the file and replaces the existing file

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Class Diagrams

The systems' class diagram is listed below. The class diagram has shown the attributes, and the relationships between the classes of Digital Music Sampler.

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Function List

Below is a table of medthods for each classes

SynthUI	Keyboard	Key	Synth Controller	Recorder	MainApp	AudioPlayer	MidiPlayer	MidiNote	Trimmer
getVolume()	KeyBoard constructor	Key constructor	SynthController constructor	Recorder constructor	void main(String[])	AudioPlayer constructor	MidiPlayer constructor	MidiNote constructor	Trimmer constructor
getOctave()	void createPitchValues()	void keyPressed()	void playNote(int note)	void startRecording()		void getInputStream()	void open()	void setVolume(int)	void load()
setVolume(int Volume)	void createKeys()	void keyReleased()	void playNote(MidiNote note)	void stopRecording()		SourceDataLine getLine()	void close()	int getVolume()	void play()
setOctave(int Octave)	Key getBKey(int i)	void createPopupMenu(KeyAction kAct)	void changeInstrument(int)	File getNewFile()		void start()	void playNote(int, int)	void setPitch(int)	void trim()
setPitchBend(int PitchBend)	Key getWKey(int i)	File getFile();	void playBack()	void run()		void run()	void playNote(MidiNote)	int getPitch()	void save
setMute(int MUTE)	getKey(String)		void recording(boolean record, boolean clearRecords)			void stop()	void setPitchBend(int)	void setTime(long)	void createWaveForm(byte[])
getPitch()	getPitchValue(String)						boolean hasPitchBend()	long getTime()	void paint(Graphics)
getInstrument()							void changeInstrument(int)	void setInstrument(int newValue)	AudioFormat getFormat()
getMidiNote(int note)								int getInstrument()	void setFormat(AudioFormat)
void keyPressed()
void keyReleased()

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Sequence Diagrams

• Recorder

• Playback Original Sound

• Selecting Files to key

• Playback Custom Sound

• Pitch

• Trimmer

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Pre And Post Conditions

This section is a pre & post condition for classes

MainApp

void main(String args[]) pre-conditions: A keyboard interface should appear on the screen post-conditions: creates a new instance of SynthUI makes its visible

SynthUI

new Key pre-conditions: 1)All user interface should appear post-conditions: Response to the key pressed and doing appropriate action

Keyboard

new Keyboard pre-conditions: None post-conditions: A keyboard of 10 black keys and 15 white keys is created. Each key is assigned a different note or sound file to play

SynthController

new Key pre-conditions: 1)None post-conditions: Controlled the recording and playing midi sound

Key

new Key pre-conditions: 1)A valid foreground colour, background colour, note and sound file are passed to the constructor post-conditions: Response to the key pressed and playing the sound

MidiNote

new Trimmer() pre-conditions: 1)A valid time, volume, pitch, instrument, channel must be set post-conditions: None

AudioPlayer

new Player(soundFile) pre-conditions: 1)A valid sound file is passed to the constructor 2)A new thread is created and start post-conditions: The sound is played back till the end

Recorder

new Recorder() pre-conditions: 1)A record user interface should pop up 2)A file should be created 3)You can record from an output to that file 4)You can stop recording and automatically save the file post-conditions: creates a new instance of Record makes its visible It creates a file and record into it

MidiPlayer

new Trimmer() pre-conditions: 1)The synthesizer must be created and open 2)The instruments must be loaded 3)The channels must be initialized post-conditions: None

Trimmer

new Trimmer() pre-conditions: 1)A trimmer user interface should pop up 2)A file is loaded 3)The file type should be .wav, .au, or .aiff 4)The file should have correct format post-conditions: A new trimmed file is created and saved

Test Cases

he test case is a method that tests the functionality of system. The test that carries out below is to determine whether the system has met all the designing requirements.

Scenario 1:

1. Open GUI
2. Play the desired note (example Middle C)
3. Play the note above (example D)
4. Move the pitch Slider to 1
5. Play the original key again (middle C in this Case)
6. Test to see if Step 5 sounds the same as step 3
7. If so test is successful, If not failed

Changing the Pitch Test

Actions	Inputs	Results	Pass/Fail
1. Opens Program Digital Music Sampler	N/A	Check the Pitch should be at 'Normal' position, which is a default	Passed
2.Press a 'C' key using the mouse Listen to the sound and take to note of it	C	N/A	Passed
3. Slide the Pitch to -1 using mouse to slide the Pitch bar	0	At-1 position	Passed
4. Press a 'C' key again Listen to the sound and take to note of it	N/A	The sound should be different sound form step 2.	Passed
5. Now slide the Pitch to +1 using mouse to slide the Pitch bar	N/A	At +1 position	Passed
6. Press a 'C' key again Listen to the sound and take to note of it	N/A	The sound should be different sound form step 2.	Passed
8. Clicks Default Button	16383	Returns Pitch to default value - Normal	Passed
9. Clicks Exit	N/A	Program closes	Passed

Scenario 2:

1. Open GUI
2. Select record Mode Button
3. In the Recorder Window, Select record Button
4. Then click stop (after recording the sound via the microphone input)
5. Ignore trimming
6. Exit recorder window
7. Check if the file has been created, if not created test failed.

Recording Test

Actions	Inputs	Results	Pass/Fail
1. Opens Program Digital Music Sampler	Click on the "Record" button	The recording user interface is open	Passed
2. Start recording	Press the 'Record' button	The recording is started, and the button caption changed to "Stop"	Passed
3. Recording	feed sound to the microphone	the sound is recorded	Passed
4. Stop recording	Press the 'Stop' button	The recording is stop and "voice0.wav" is saved and button caption now changed to Record and ready for next recording...	Passed
5. Close the window	Click on the Close "X" button	Window closes and return to main application	Passed
6. Testing the recorded sound	Complete scenario 3 (Playing wav files Test)	The recorded sound is playing back successfully	Passed

Scenario 3:

1. Open GUI
2. Right Click on the Key (this instance middle C)
3. Select 'select sound...' option
4. Choose the desired wave file (in this case sample1.wav)
5. Test whether the "voice" is played once that Key is pressed. If so then test successful.

Playing wav files Test

Actions	Inputs	Results	Pass/Fail
1. Opens Program Digital Music Sampler	N/A	The Graphic user interface would pop up	Passed
2.Right click on the middle key "c"	N/A	Another Graphic user interface pops up with two options (use default sound, select sound...).	Passed
3. Click on "Select sound..." button	N/A	A new user interface would appear with a list of .wav files you recorded beforehand	Passed
4. Select the wav file for the middle key "c" (this case voice0.wav)	voice0.wav	Sample1.wav would be loaded onto the key "c"	Passed
5. Press the middle key "c"	voice0.wav	The voice0.wav file should be played instead of the default sound file.	Passed
6. Clicks Exit	N/A	Program exits	Passed

Scenario 4:

1. Open GUI
2. Play several "natural" keys in rapid succession
3. Listen to see if the "voices" overlap
4. If they do overlap then test successful

Rapidly playing keys Test

Actions	Inputs	Results	Pass/Fail
1. Opens Program Digital Music Sampler	N/A	The Graphic user interface would pop up	Passed
2.Press keys 'q' 'w' 'e' 'r' at the same time	q w e r	Playback of the keys pressed	Passed
3. Listens for overlapping sound	N/A	N/A	Passed
4. Clicks Exit	N/A	Program closes	Passed

Scenario 5:

1. Open GUI
2. Load the recorded sound
3. Play the sound
4. Trim the sound
5. Save the sound
6. Play back the trimmed sound
7. If so test is successful, If not failed

Trimming Test

Actions	Inputs	Results	Pass/Fail
1. Opens Program Trimmer interface	Click on the "Trim" button	The Trimming User Interface is open	Passed
2. Loading recorded sound	Click on the "Load" button	The system file dialog is open and prompt for opening a file	Passed
3. Playing back the recorded sound	Click on the "Play" button	The sound is playing back	Passed
4. Trimming the sound	Click on the left and right of the sampling graph	The trimmed off portion of the sound is highlighted red and green	Passed
5. Saving the trimmed sound	Click on the "Save" button	The system file dialog is open and prompt for saving the file	Passed
6. Playing the saved file to verify the trimming	Click on the "Play" button	The trimmed sound is playing back	Passed
7. Closing the trimming	Click on Close button	Return to main application	Passed

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Screenshots

Main GUI - A figure below is a final graphical user interface of the project, which has included the key interface - Volume, Pitch, and Octave Slide bars, Record, Trimmer, Exit, and Default buttons and Keyboard.

Recorder GUI - When the user click on Record button, a new Recorder window will pop up as below;

Trimmer GUI - Again if the user click on Trimmer button, a new window will pop up as below;

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Reference

1. Class Diagram - Wikipedia.org[1]

2. Use Case - Wikipedia.org[2]

3. Sun Java Sound API - [3]

4. Wu C. T., 2001, An Introduction to Object-Oriented Programming with Java, 2ndED, McGraw-Hill, US.

5. Larman C., 2002. Applying UML and Patterns,2ndED.,Prentice-Hall International, NJ, US.

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Instructor comments

Your usage scenarios are unusually concise... yet I can't fault them! Well done.

The CRC cards were intended to be an aid to discovering classes, I wasn't really expecting them to be part of your final deliverable.

Your use cases need names. So far they look pretty good (although I suspect you will find you need more later).

(JohnR 21st Aug 06)

Looks like you are making progress. Looking forward to seeing more. JohnR 11:05, 9 September 2006 (UTC)