SO I MEAN IT'S SOMETHING THAT YOU COULD CONCEIVABLY REPRESENT IN SOME SORT OF LOW SORT OF R YOU KNOW LOW BIT RATE REPRESENTATION I GUESS AND THEN MAYBE YOU'D NEED SOME SORT OF CORRECTION TO UM TO CORRECT MINOR PHASE DISCONTINUITIES AT SOME POINT IN TIME I ALSO PLAY WITH THAT AND FOR EXAMPLE WHAT I FOUND I WELL IN THIS CASE UH WE ARE NOT TRYING TO ENCODE THE SPEECH SIGNAL WE ARE TRYING TO ENCODE SOME CARRIER WHICH IS MUCH EASIER I WOULD SAY BECAUSE YOU CAN REALLY IM YOU CAN SEE THAT EVEN SO WHAT I WAS TRYING TO ENCODE AT THE PHASES SO I JUST FOUND THAT UH TWO BITS IS ENOUGH FOR THAT AND YOU REALLY DON'T HEAR THE DIFFERENCE SO IF YOU KEEP ALL THE SPECTRAL LINES AS THEY WERE THERE BUT YOU WERE JUST UH QUANTIZING WITH TWO BITS OR THREE BITS FOR AMPLITUDE TWO BITS FOR FOR PHASE SO IT'S OKAY THE PROBLEM IS THAT YOU HAVE TO TRANSMIT MANY OF THEM 'CAUSE THERE IS NOT JUST ONE DOMINANT COMPONENT BUT USUALLY MORE OTHERS WHICH ARE QUITE SMALL RIGHT OR WHAT YOU HAVE TO DO THEN YOU HAVE TO DECREASE THE THE THE SIZE OF NOT ONE SECOND BUT YOU HAVE TO GO DOWN BECAUSE THEN YOU CAN GET JUST VOICED PART AND UNVOICED PART YOU KNOW ONE SECOND IT'S USUALLY MIXED RIGHT SOMEHOW TOGETHER BUT YOU DON'T DO ANY VOICE UN VOICE DECISION NO YEAH THE THAT'S EVEN ADVANTAGE I THINK FOR THIS APPROACH YEAH YEAH YEAH SORTA THE MODELLING IT'S REALLY ANOTHER ISSUE LIKE YEAH YEAH YEAH YEAH YEAH YEAH AND THEN YOU HAVE TO COMBINE ALL THIS HARMONIC MODEL AND NOISE MODEL SO AGAIN YOU MAY END UP SOME BUT FOR EXAMPLE WHAT WE ALSO FOUND IS THAT IF YOU USE JUST THE HILBERT ENVELOPE THAT THAT ONE WHICH IS TRYING TO APPROXIMATE THAT ENERGY IN SOME LOW BAND LIKE AR AROUND TWO HUNDRED T UH HERTZ AND YOU TAKE A LOOK ON THE SIGNAL ON THE TRAJECTORY YOU CAN SEE THAT IT WORKS LIKE KIND OF UM VOICE DETECTOR BECAUSE UH FOR A LOW ENERGIES THERE IS USUALLY NOISE FOR HIGH ENERGIES THERE IS KIND OF A HARMONICITY SO IT WORKS PRETTY WELL FOR THAT SO WE MIGHT USE THIS ONE INFORMATION FOR THAT BUT YEAH I THINK SO YEAH MM-HMM SO THIS IS WHAT ALAN BLACK'S CODE USES BUT IT'S VERY SPEAKER DEPENDENT WH ON WHAT SORT OF BAND WIDTH YOU'D LOOK AT THIS HILBERT ENVELOPE DEPENDING ON THE PITCH DEPENDING ON THE PERSON Y YOU'LL GET A DIFFERENT AMOUNT OF SMOOTHING AND A CERTAIN SORT OF SO I MEAN YOU KNOW IF IT'S A FEMALE SPEAKER FOR INSTANCE YOU YEAH SO IT'S SORTA TRICKY YEAH YEAH YEAH THAT'S THAT'S A PROBLEM BUT ANYWAY YOU DON'T REALLY NEED HARD DECISIONS NO LIKE VOICED UNVOICED UH N NO Y YEAH BUT FROM MEMORY THAT THAT BASIC SCRIPT THAT THEY HAD WASN'T WASN'T VERY UM EFFECTIVE I MEAN MAYBE IF YOU DID SOME SORT OF INITIAL FIRST P GUESS AND THEN AND THEN CHOSE YOUR SMOOTHING FACTOR BASED ON THAT 'CAUSE IT IT YOU KNOW SELECTING AT ANY PARTICULAR POINT OF WHAT THE WHAT THE PITCH IS AT THE MAY BE INACCURATE BUT IF YOU ESTIMATED IT OVER A SECOND YOU SHOULD BE ABLE TO GET A DECENT ESTIMATE I'D I'D THINK BUT DO YOU REALLY REALLY NEED IT OR LIKE VOICED UNVOICED YEAH BUT YEAH YEAH BUT IT'S NOT REALLY YOU NEED T YOU DON'T NEED TO SPECIFY AT EACH POINT IT'S VOICED OR YEAH YEAH WELL IT'D BE NICE TO IT WOULD BE NICE TO REALLY SEE WHAT THIS WHAT YOU'RE A ACTUALLY TRYING TO RECONSTRUCT HERE WHAT WE ARE TRYING TO RECONSTR HOW DOES IT LOOK LIKE OR SURE YEAH MORE OR LESS HMM IT'S KIND OF UH NOT FREQUENCY LET'S SAY AMPLITUDE MODULATION WHEN YOU HAVE JU JUST THE CARRIER AND THAT MODULATION SIGNAL RIGHT LIKE YOUR DELAY YEAH YEAH YEAH YEAH YEAH SO THEN YEAH THEN IT'S NOT EXACTLY AMPLITUDE MODULATIONS OR IT'S IT'S IN BETWEEN MAYBE YEAH S YEAH BUT ANYWAY WHAT ALSO THE OTHER APPROACH WHICH IS POSSIBLE TO USE THE OTHER IS ONE TO KEEP THE PHASE LIKE THIS ONE LIKE TWO SPECTROGRAMS ONE THE PHASE AND ONE THE MAGNITUDE AND WELL I CAN AGAIN PLAY IT AND IT WORKS ON TWO KILO BITS PER SECOND QUITE WHAT UH NO WHAT UH HE WAS DOING HE WAS USING IT FOR SPEECH RECOGNITION WHAT I WHAT I KNOW BUT FOR SPEECH CODING NO NO NO IT WAS I DON'T KNOW FOR SPEECH CODING YOU MEAN SO HE DOESN'T REALLY CARE ABOUT THE BAND WIDTHS OR HE WANT TO HAVE THE QUALITY NO LIKE YEAH BUT EVEN ESPECIALLY THE AUDIO SERIES AND THE THAT THAT'S WHAT HE WAS TELLING LIKE YEAH AT LEAST EVEN TEN K. BIT TWENTY KILO BITS ALSO IS OKAY SO BUT HE'S UH HE'S NOT I THINK FINISHED WITH ALL THAT THING HE'S JUST TRANSMITTING ALL THE PHASE AND THEN BUT HE'S ENCODING THE ENVELOPE YEAH YEAH I THINK SO THERE ARE M MORE PAPERS WHICH ARE USING THIS APPROACH LIKE TRYING TO ENCODE THE MAGNITUDE SPECTRUM OR SPECTROGRAM UH THE PHASE OR YOU JUST UH RE CAN AGAIN THE PHASE CAN BE REPLACED BY THE NOISE WHICH IS PRETTY GOOD SO THAT'S UH THE BENEFIT UH VARIABLE APPROACH SO IF YOU REALLY DON'T HAVE A BAND WIDTH YOU JUST CAN REPLACE IT BY NOISE AND IT WORKS OF COURSE THEN IT DOESN'T SOUND AS THE ORIGINAL BECAUSE IT'S MORE WHISPERED OR WHATEVER BUT YOU CAN UNDERSTAND WELL MM AND FOR EXAMPLE UH IF YOU MENTION THIS ONE APPROACH WITH THE THAT UH TRAJECTORY OF THE PHASE OF UNWRAP PHASE RECRE UH I ALSO USE BECAUSE YOU CAN DO IT HERE WHEN YOU GET INTO UH THIS DOMAIN WHERE YOU APPLY UH OR YOU'RE TRYING TO COMPUTE UH S POWER SPECTRUM IN IN ORDER T LET'S SAY THAT THIS KIND OF TRAJECTORY IT DOESN'T IN FIT THE SAME FREQUENCY OVER TIME DOMAIN BUT HERE YOU ARE TRYING TO COMPUTE UH DOING A TO DO LINEAR PREDICTION SO WE ARE JUST DOING F. F. T. RIGHT THEN APPLYING UH POWER IN ORDER TO GET UM TO S TO POWER DOMAIN AND THEN I. F. F. T. RIGHT SO YOU GET THE AUTO CORRELATION COEFFICIENTS SO BEFORE YOU'RE APPLYING UH POWER SPECTRUM YOU CAN AGAIN GET THE YOU HAVE GOT A COMPLEX F FREQ FREQUENCY OR COMPLEX SPECTRUM YOU CAN GET THE PHASE RIGHT AND THE PHASE LOOK QUITE SIMILAR LIKE THIS SO YOU MIGHT SEE IT'S IS MORE LESS LIKE A LINE OH RIGHT BUT NORMALLY THAT'S THAT'S WHEN THE COMPONENTS ARE NOT ACTUALLY PROBABLY GONNA BE AUDIBLE ANYWAY IN VOICED SPEECH RIGHT SO YEAH YEAH IT'S IT IS VERY DIFFERENT YEAH THEN YOU ARE DOING IN DIFFERENT DOMAIN I THINK THIS IS IN FREQUENCY DOMAIN THIS IN TIME DOMAIN UM IT IS QUITE IT'S QUITE SENSIBLE TO ANY QUANTIZATION WHAT I FOUND REALLY IT LOOKS LIKE THE LINES SO YOU JUST SAY OKAY LET'S P LET'S PUT THE LINE THERE BUT IT DOESN'T WORK