Madhav Rao (ECE) The University of Alabama Research Professors – Dr. John. C. Lusth (CS) Madhav Rao March 30 RRA: An audio format for single-source music.

Madhav Rao March 30

Madhav Rao (ECE)

The University of Alabama

Research Professors – Dr. John. C. Lusth (CS)

RRA: An audio format for single-source music and lyrics

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Madhav Rao March 30

WAV Format RRA Format

Source: J .C. Lusth. Songlib: A library for music programming across the computer science curriculum. In American Society for engineering Education, 2007.

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RRA: Readily Readable audio

MP3 Format

Introduction to RRA format for audio

Madhav Rao March 30

RRA format for audio

Source: J. C. Lusth, http://beastie.cs.ua.edu/songlib/

RRAUDIO%%<amplitude1><amplitude2><amplitude3>…………..…………..…………...

Header

Data

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RRAUDIO! Hohner Pocket Pal Harmonica ! D# ! recorded by Becky SmithsampleRate: 44100 bitsPerSample: 24 channels: 1 samples: 44100%%!amplitude begins001-2…………..…………..…………...

Defaultchannels: 1sampleRate: 44100samples: 0bitsPerSamples: 16

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RRAUDIOchannels: 1 %%<amplitude0_channel0><amplitude1_channel0><amplitude2_channel0>…………..…………..…………...

RRAUDIOchannels: 2 %%<amplitude0_channel0><amplitude0_channel1><amplitude1_channel0><amplitude1_channel1>…………..…………..…………...

RRAUDIOchannels: 4%%<amplitude0_channel0><amplitude0_channel1><amplitude0_channel2><amplitude0_channel3><amplitude1_channel0><amplitude1_channel1><amplitude1_channel2><amplitude1_channel3>

RRA format for multiple channels: interleaved

Source: J. C. Lusth, http://beastie.cs.ua.edu/songlib/

Madhav Rao March 30

arplay tool: native audio player for RRA files

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Source: http://www.alsa-project.org/

arplay <filename>

arplay <filename1> <filename2> ….. loop

arplay <filename1> <filename2> ….. shuffle

arplay <filename1> <filename2>……

<rra-filters> <filename> | arplay

arplay <filename> scaling <XXX>

Madhav Rao March 30

Drums track developed for crozier song

Drum Bass and Floor

static voiddrumBassFloor()    {    drum(Q,bassinst,1);    drum(Q,floorinst,1);    drum(I,bassinst,1);    drum(I,bassinst,1);    drum(Q,floorinst,1);    }

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Crash drum

static voidcrashDrum ()    {     drum(I,crashinst,1); }

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Drums track developed for crozier song

Madhav Rao March 30

Drums track developed for crozier song

intmain()    {    openOutput("drum.rra",0,0);    intro();    verse1();    refrainStart();    rest(Q);    verse2();    refrain();    bridge();    refrainA();    rest(W+W);    ending();    closeOutput();    return 0;    }

Crozier drum track

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Madhav Rao March 30

Karaoke system developed in RRA

backwards(1);addComment("!lGood people of this town...");forwards(1);for (i = 0; i < 2; ++i)   drumBassFloor();

backwards(1);addComment("!lYou'd do well to gather around...");forwards(1);for (i = 0; i < 2; ++i)   drumBassFloor();

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Madhav Rao March 30

Lyrics inserted in drum track of crozier song

000!lGood people of this town...000...............104210251053!lYou’d do well to gather around...103910401072

lyrics inserted in RRA

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Madhav Rao March 30

Lyrics displayed on screen while playing the drum track

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arplay program flow

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Lyrics displayed on screen

Samples passed to sound device

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RRAUDIOSamples: <number-of-samples>%%<amplitude1><amplitude2><amplitude3>…………...!amplify 10…………..…………..…………...

RRA based filters: amplify

Amplified audio track

Original audio track

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test.rra

rraamplify test.rra

Madhav Rao March 30

RRAUDIOSamples: <number-of-samples>%%<amplitude1><amplitude2><amplitude3>…………...!drum snare pattern 8 Quarter length scaling 1.25…………..…………..…………...

RRA based processors: drum fillers

Audio track with added drum track on another channel

Original audio track: mono channel data

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test.rra

rradrum test.rra

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Pattern 1 Quarter length

Pattern 2 Quarter length

Pattern 4 Quarter length

Pattern 8 Quarter length

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Madhav Rao March 30

Pattern 8 Quarter length Pattern 8 Half length

Pattern 8 Whole length

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Madhav Rao March 30

RRAUDIOSamples: <number-of-samples>%%<amplitude1><amplitude2><amplitude3>…………...!compress 10…………..…………..…………...

RRA based filters: compression

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test.rra

rracompress test.rra

Madhav Rao March 30

RRAUDIOSamples: <number-of-samples>%%<amplitude1><amplitude2><amplitude3>…………...!crossover samples 11025 channels 0 1…………..…………..…………...

RRA based filters: crossover

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test.rra

rracrossover test.rra

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RRA based multiple filters: crossover, compress, amplify

Original audio track Crossover

Crossover-amplified-compressed

Crossover- amplified

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Madhav Rao March 30

RRA project used in CS150 in Fall 2009

Students were asked to develop code to strip the initial silence.

The project involved: loops, file-operations such as reading and writing, and functions.

Stepwise refinement method was included to complete the project.

Initial silence

Original audio track given to students

Processed audio track

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Other RRA projects to students in the future

RRA loop utility for first year programming students

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Original audio track

Looping over 10 times

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RRA add utility for first year programming students

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Audio track 1 Audio track 2

Interleaved audio in a single track

Madhav Rao March 30

RRA add utility for first year programming students

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Audio track 1 Audio track 2

Interleaved audio in a single track Interleaved audio in a single track with a flair of longer audio

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Conclusions

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A readily readable audio format for single-source music and lyrics is demonstrated.

A readily readable audio format is used in the University of Alabama to reproduce drums track of a complete song.

A native RRA player is developed (arplay).

An RRA based student project was used in CS150 curriculum in Fall 2009.

Future student projects can be easily incorporated in introductory programming curriculum.

Madhav Rao March 30

Future work

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A web based RRA interface needs to be developed with an inbuilt RRA VIEWER similar to audacity tool.

A real time multimedia tools such as forwards, rewind, slow, fast needs to be developed.

Madhav Rao March 30

Acknowledgements

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Thanks College of Engineering, UA.

Thanks Computer Science Department, UA.

Thanks Dr. Susan. L. Burkett (ECE), UA.