MICROCOMPUTER SYSTEMS 1

SulTan BINHUMOODFinal Project Presentation

PROJECT INFO

• My project idea is based on playing sound

displaying different effects seen in everyday

experiences.

EFFECTS

CHORUSchorus effect (sometimes chorusing effect) occurs when individual sounds are roughly the same and nearly (but never exactly) the same pitch converge and are perceived as one

ECHOA time-delayed electronic reflection of a speaker's voice.

CHORUS - CODING

• for(i = 0; i < BUFLEN; i++)• {• delay = (int)((1 - (cos(6.28 * 0.4 * input / 1000))) * 20); //eq'n for delay = D/2(1-(cos(2*pi*n*f))•

• delay = input - delay; //usage of the delay in the output equation• • if (delay < 0)• {• delay = 1000 + delay; //if the value of the delay go below 0, it retakes 5000 samples• } //it basically "goes back to the start"

• buffer1[input] = (short) (pIn[i * 2]); • buffer2[input] = (short) (pIn[i * 2 + 1]);

• x = (int)(buffer1[input] + 2 * buffer1[delay] / 3); //2/3 is alpha, which is like a volume control;it controls the intensity of the effect's signal

• y = (int)(buffer2[input] + 2 * buffer1[delay] / 3); //x and y both have 16 bits stored in them•

• if(input >= 1000 - 1) //if the number of samples go beyond 5000, resets it to 0• input = 0;• else• input++;•

•

• pOut[i * 2]= (x);• pOut[i * 2 + 1]= (y); // display output in the output buffer• }• }

ECHO - CODING

• void Echo_Effect(short *pIn, short *pOut)• {• int i;• short buffer1[1000];• short buffer2[1000];• static int input = 0; • int x, y=0;

• for(i = 0; i < BUFLEN; i++)• {• buffer1[input] = (pIn[i * 2]) + (0.6 * buffer1[input]);• buffer2[input] = (pIn[i * 2 + 1]) + (0.6 * buffer2[input]);

• x = (int) (buffer1[input]);• y = (int) (buffer2[input]);•

• if(input>= 1000-1)• input = 0;• else• input++; •

• pOut[i * 2] = (x);• pOut[i * 2 + 1] = (y); // display output in the output buffer•

• }• }

RUN PROJECT

• Run the actual project and show how the effects work.

• > First select Passthrough to show the actual sound

• > Next show Chorus Effect

• > Show Echo Effect

THE END

• Any questions about the project or suggestions to improve the project?