ENGI 2420 Structured Programming (Lab Tutorial 7)

1. ENGI 2420Structured Programming (Lab Tutorial 7) Memorial University of Newfoundland

2. 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

3. 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)

4. 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

5. 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 10 45 -80 23 78 -39 -65 -20 30 79 65

6. writeSoundData • void writeSoundData(int snd[], int size) • Output (to cout) the size samples in snd using the format described above

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.

8. fuzzBox • Example: • Initial value of the array. +200 +10 -190 -150 +20 • clip = 100 • Final value of the array +100 +10 -100 -100 +20

9. 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

10. 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

11. 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

12. 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

13. Running with MMGood • 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

14. Running with MMGood • Wait patiently for your program to finish • Play the output sound