actionscript 3 - Remove unvanted clicks in generated sound in AS3 -

i having following problem when generating sound wave in flash. generator part :

const sampling_rate:int = 44100; const two_pi:number = 2 * math.pi; const two_pi_over_sr:number = two_pi / sampling_rate; const sample_size:int = 8192 / 4;   function generatesine(fq:number):bytearray { var bytes:bytearray = new bytearray(); var sample:number; var amp:number = 1;   (var i:int=0; i<sample_size; i++) {     sample = amp* math.sin(i  * two_pi_over_sr *   fq  );     bytes.writefloat(sample); }   bytes.position = 0; return bytes;  } 

and playback part:

function playbacksamplehandler(event:sampledataevent):void { var sample:number;  (var i:int = 0; <  sample_size && sounddata.bytesavailable; i++) {     sample = sounddata.readfloat();     event.data.writefloat(sample);     event.data.writefloat(sample); }  }     function onclickplay(e:mouseevent)  { sounddata= new bytearray();     var sound:bytearray= new bytearray();     sound=generatesine(440); sounddata.writebytes(sound,0,sound.length); sounddata.position = 0; morphedsound.addeventlistener(sampledataevent.sample_data, playbacksamplehandler); soundchannel = morphedsound.play();               } 

quick explanation: write values sine function bytearray , playback handler reads array , plays sound. write 1 8192/4 sample buffer.

problem: problem when there annoying clicks on end of sound, artifacts of sine wave being cut on value other 0. question how can avoid this?

bonus: know how can generate example 100 ms of sine wave when buffers in flash strict i.e. 2048 8192 ?

links: if helps code based on tutorial http://www.bit-101.com/blog/?p=2669 , own explorations.

you need preserve phase of sine wave occurs @ end of sample data processing. otherwise sine wave not continued smoothly , clicks speak of.

var totalsamples:int=0; function generatesine(fq:number):bytearray { var bytes:bytearray = new bytearray(); var sample:number; var amp:number = 1;   (var i:int=0; i<sample_size; i++) {     sample = amp* math.sin((i+totalsamples)  * two_pi_over_sr *   fq  );     // uses stored phase ^^^     bytes.writefloat(sample); } totalsamples+=sample_size; // preserves phase between subsequent samples  bytes.position = 0; return bytes; 

}

update: i've noticed calling generator twice in row - awful. must never call function twice if need 1 result of work.

function onclickplay(e:mouseevent) { sounddata= generatesine(440); // why using writebytes if can use assignment? sounddata.position = 0; morphedsound.addeventlistener(sampledataevent.sample_data, playbacksamplehandler); soundchannel = morphedsound.play();
}

also, make sound end full (half-)wave of sound , remove last click need, use technique:

function generatesine(fq:number,cleanfinish:boolean=false):bytearray { var bytes:bytearray = new bytearray(); var sample:number; var amp:number = 1;   (var i:int=0; i<sample_size; i++) {     sample = amp* math.sin((i+totalsamples)  * two_pi_over_sr *   fq  );     // uses stored phase ^^^     bytes.writefloat(sample);     if (cleanfinish)        if ((math.abs(sample)<(sampling_rate/fq/3))&&(i>sample_size-sampling_rate/fq)) break;      // triggers drop if sampling last wave } totalsamples+=i; // preserves phase between subsequent samples  bytes.position = 0; return bytes; 

}

call function optional boolean parameter set true receive correctly terminated wave.