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Listing 6 ends by scaling the gain factor by 8000 to produce a reasonable audio output level.

Compute the gain for the left and right speakers

Listing 7 examines the sign (positive or negative) of the current value of the sinusoidal function (based on the pulse frequency relative to the center frequency) and uses that information to compute gain factors that will turn one speaker on and turn the other speaker off.

Listing 7 . Compute the gain for the left and right speakers.
if(freq>= centerFreq){ leftGain = gain;rightGain = 0;//switch off the right channel }else{rightGain = gain; leftGain = 0;//switch off the left channel}//

Required audio data format

As you learned in an earlier module, given the values that we are using in the AudioFormatParameters01 object, the format requirements for monaural and stereo are shown below. (Note that in both cases, each audio value must be a signed 16-bit value decomposed into a pair of 8-bit bytes.)

Monaural, channels = 1

For mono, each successive pair of bytes in the melody array must contain one audio value. The element with the lower index must contain the most significant eightbits of the 16-bit audio value.

Stereo, channels = 2

For stereo, alternating pairs of bytes must each contain one audio value in the same byte order as for mono. One pair of bytes is routed to the left speakerand the other pair of bytes is routed to the right speaker (almost) simultaneously.

Within the four bytes, the pair with the lowest index is routed to the left speaker and the other pair is routed to the right speaker.

You learned how to use the putShort method belonging to an object of the ByteBuffer class to deposit the short data into the byte array in the earlier module titled Jbs2030-A Pure Sinusoidal Tone .

Deposit stereo audio data in the melody file

Listing 8 used the information from above to compute the current audio value of the pulse and to deposit it into two consecutive pairs of bytes in the melody array. Note that the putShort method is called twice, once for each channel. Note also that the values of leftGain and rightGain are used to scale each audio value so that it will be emitted from only one of the two stereo speakers.

Listing 8 . Deposit stereo audio data in the melody file.
byteBuffer.putShort((short)(leftGain*Math.sin(2*Math.PI*freq*time))); byteBuffer.putShort((short)(rightGain*Math.sin(2*Math.PI*freq*time)));}//end for loopreturn melody; }//end method getMelody//-------------------------------------------------------------------------// }//end class AudioGraphSinusoidal

Listing 8 returns a reference to the melody array when the for loop terminates.

Listing 8 also signals the end of the getMelody method and the end of the AudioGraphSinusoidal class.

Controlling stereo speaker output levels

This module demonstrates one way to control the output levels from the two speakers in a stereo melody. It is not necessary that one speaker be turnedcompletely off and the other speaker turned completely on as is the case here. The relativelevels of the audio outputs from the two speakers can be controlled by adjusting the relative values of the left and right gain values.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
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