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ENGI 2420Structured Programming

(Lab Tutorial 7)

Memorial University of Newfoundland

2 ENGI 2420 – Structured Programming

Lab Tutorial 7

Preferences in Eclipse

Warning message “no newline at end of file” How to enable automatic newline insertion in

Eclipse

check Window -> Preferences -> C/C++ -> Editor -> Ensure newline at end of file when saving

How to show line number in Eclipse

check Window -> Preferences -> General -> Editors -> Text Editors -> Show line numbers

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Lab Tutorial 7

Assignment-7 Purpose of this assignment

a filter to implement a fuzzbox effect on a sound (music) file or an echo effect

Structure of C++ files- assign7.h (downloadable): contains the declarations for the functions

- a7main.cpp (downloadable): main function that can be used as test code

- assign7.cpp: contains your implemented functions (only submit this one via web-submit)

- you may want to create your own test code in a separate .cpp file (do NOT submit your test code)

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Lab Tutorial 7

readSoundData int readSoundData(int snd[]) Read the sound data from cin and store it in

snd, which can be assumed to be big enough for at least MAX_SND_SIZE (500000) samples. Return the number of samples read, if successful. If the number of samples input is invalid, then return 0

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Lab Tutorial 7

Data Format

Must be strictly adhered to so that your program can interact with MMGood

The data consists of a sequence of integers each on a separate line

The first number is to be interpreted as the number of samples to follow (i.e., the size of the data), while the remaining numbers are the data

1045 -8023 78 -39 -65 -20 30 79 65

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Lab Tutorial 7

writeSoundData

void writeSoundData(int snd[], int size)

Output (to cout) the size samples in snd using the format described above

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Lab Tutorial 7

fuzzBox int fuzzBox(int snd[], int size,

int clip) Clip the size samples in snd to a maximum

amplitude (magnitude) of clip. Elements of snd whose magnitude is greater than clip should be set to clip or -clip appropriately, so as not to change the sample's sign. Return the number of samples that had their value changed.

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Lab Tutorial 7

echoBox void echoBox(int snd[], int size,

int delayTime) Add a delayed copy of the sound to the sound Example

90 -100 50 60 70and the delay time is 2, then the final value of the sample will be 90 -100 140 -40 120

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Lab Tutorial 7

Running the Program

Our main program uses a "program argument" to select the effect (fuzz or echo). 0 is for fuzz and 1 is for echo

Windows: from the (windows) command line you launch your program as follows:

C:\My Documents\courses\sp\workspace\A7> .\debug\A7 0

or C:\My Documents\courses\sp\workspace\A7> .\debug\A7 1 In Eclipse, you can use the "Run > Open Run Dialog..."

command and then edit the "program arguments" to be either "0" or "1" to select fuzzBox or echoBox respectively

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Lab Tutorial 7

Running with MMGood MMGood is a java program that will execute your program on

actual.wav files so you can hear them working Download mmgood.jar to your hard drive Download the sample .wav files: engage.wav and guitar.wav For windows

– Download mmgood.bat and put it in the same directory

– Double click on mmgood.bat For unix/linux/mac

– Download mmgood.sh to the same directory

– Make this file executable.

– Execute the mmgood.sh file

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Lab Tutorial 7

Running with MMGood

Once mmgood's main window has appeared, and you have compiled your project, you can

– Load an input .wav file

– Play the input .wav file

– Select your assignment 7 executable. (It is in the Debug subdirectory of your project directory and, in Windows, its name will end with ".exe".)

– Set the argument to be 0 or 1

– Run the executable

– Wait patiently for your program to finish

– Play the output sound