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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

what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
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Brian Reply
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Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
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LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
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Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
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what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
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
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
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biomolecules are e building blocks of every organics and inorganic materials.
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research.net
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sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
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nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
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absolutely yes
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