OH MY GOD YEAH STILL DOESN'T FEEL NATURAL I I WISH YOU KNOW THE THE THE THE ROOM WOULD JUST DETECT WHEN AN WHEN A MEETING'S STARTED IT STARTING VOILA COOL SO YOU BETTER START IT WAS YOUR IDEA SO YEAH NO SO I THOUGHT THAT WE MIGHT S T SPEAK A LITTLE BIT ABOUT SPEECH CODING BECAUSE NOBODY IS DOING HERE SPEECH CODING AND I WOULD LIKE TO HAVE SOME MAYBE FEEDBACK BECAUSE EXCEPT ME I'VE I'VE SUPPOSED TO SOME SPEECH CODING STUFF HERE WITH HYNEK UH BUT YOU KNOW THAT LITTLE BIT AT LEAST THAT UH BASED ON SOME LET'S SAY HILBERT TRANSFORMS USING A LONGER TEMPORAL CONTEXT AND DERIVING SOME PARAMETERS WOULD BE TRANF TRANSCS TRANSMITTED TO A DECODER AND SO IT'S A LITTLE BIT DIFFERENT THAN THE STUFF WHICH PEOPLE ARE USING NOW WHICH IS LIKE A L. P. C. BASED AND BUT WE ARE AT THE BEGINNING WITH EVERYTHING MORE OR LESS SO STILL UM WE CAN'T UH D ENCODE A SPEECH BUT OF COURSE THERE IS THERE ARE MANY PROBLEMS WHICH WE STILL DIDN'T SOLVE AND THE BIGGEST ONE IS QUITE SIMILAR TO L. P. C. STUFF WHERE PEOPLE STILL DON'T KNOW HOW TO EXACTLY ENCODE A CARRIER OR THE SOURCE SIGNAL WE KNOW WHAT TO DO WITH THE ENVELOPE OR HOW TO APPROXIMATE THE ENVELOPE LET'S SAY UM WHEN YOU HAVE GOT WELL MAYBE UH IS IS THE WHITE BOARD WORKING OR OR NOT UM Y MAYBE SHOW US THE GENERAL SORT OF OUTLINE YOU KEEP W OKAY YOU CAN JUST WRITE IT ON THE PAPER YEAH OKAY I UH EVERYBODY KNOWS L. P. C. STUFF HOW IT WORKS SO I DON'T HAVE TO PRESENT ANYTHING MORES BUT IT'S UH M MORE OR LESS VERY SIMPLE WE HAVE LET'S SAY AT THE BEGINNING THERE IS SOME SPEECH SIGNAL WHAT WE ARE UH WE MIGHT SEE IT UH IN VERY SIMPLE WAY THAT WE ARE USING SOME HILBERT TRANSFORM H AT THE BEGINNING TO CREATE ANALYTIC SIGNAL THE ANALYTIC SIGNAL IS THE SIGNAL WHICH IS A COMPLEX WHICH YOU CAN CREATE FROM THE UH REAL UH UH SOME SEQUENCE AND IF YOU GET IF YOU APPLY HILBERT TRANSFORM ON THIS ON SUCH A SPEECH SIGNAL LIKE A REAL TRAJECTORY THEN YOU GET A COMPLEX SIGNAL AND IF YOU TAKE JUST THE AMPLITUDE THEN YOU GET HILBERT ENVELOPE CODE SO I WELL I I DON'T KNOW YEAH LET'S SAY UPS SO IS THIS DIFFERENT FROM THE ORIGINAL P. L. P. TWO STUFF THEN IS THAT YEAH IT'S U IT'S NOT P. L. P. AT ALL D HMM MM NO BUT MARIUS IS IT'S SIMILAR STUFF NO MARIUS IS ALSO USING LIKE HILBERT TRANSFORM AND THEN UH YOU'RE LIT I KNOW WHAT YOU MEAN WITH THE PU P. L. P. THEY ARE APPLYING P. L. P. WITH SOME ITERATION WITH THIS THIS ONE APPROACH SO THEY ARE DOING SOME SMOOTHING OF A SPECTROGRAM IN TWO WAYS ONE WAS RIGHT RIGHT BUT P. L. P. IS USING JUST THE SPECTRAL UH DIRECTION LET'S SAY YOU ARE DOING UH FOR EVERY TWENTY MILLISECOND PROCESSING ONE ONE FEATURE VECTOR HERE YOU ARE PROCESSING ONE SPECTRAL BAND FREQUENCY BAND RIGHT SO IT'S DIFFERENT DIRECTION WHICH WE ARE W USING BUT ANYWAY THIS IS VERY SIMPLE SO APPLYING THAT UH ABSOLUTE UH ABSOLUTE OPERATION YOU GET A HILBERT ENVELOPE AND OF COURSE THEN THERE IS THE PHASE SO IT'S JUST THE COMPLEX OPERATION AND THAT'S MORE OR LESS ALL WHAT WE ARE DOING SO NOW WHAT WE KNOW WHAT WE KNOW IS HOW TO APPROXIMATE THAT HILBERT ENVELOPE WE ARE AP WE ARE APPLYING THAT HILBERT UH HIM WHAT IS THE MARIUS' UH STUFF SO HE KNOWS HOW TO ENCODE UH THE HILBERT UH ENVELOPE USING LIKE L. S. F. S OR L. P. C. YOU ARE APPLYING AGAIN TO SOME LINEAR PREDICTION MODEL AFTER THAT BUT IT'S UH RIGHT IT'S IN A IT'S A LITTLE BIT DIFFERENCE IN NOT APPLIED IN THE FREQUENCY DOMAIN SO INSTEAD OF CLASSICAL L. P. C. DOMAIN WHERE YOU HAVE A SPECTRUM LET'S SAY SOMETHING LIKE THAT AND YOU ARE APPLYING SOME LINEAR PREDICTION MODEL WHICH IS TRYING TO APPROXIMATE THE SPECTRUM RIGHT SO THIS IS FREQUENCY IN OUR CASE WE ARE WE ARE TRYING TO APPROXIMATE S KIND OF INSTANTANEOUS ENERGY SO IF THIS IS A TIME AND YOU GET ONE AND ADD ONE FREQUENCY BAND YOU CAN SEE SOMETHING LIKE THIS AND WE ARE TRYING TO APPROXIMATE THAT ENVELOPE WHICH IS YEAH YEP HMM OKAY WE KNOW THAT WE CAN APPLY LINEAR PREDICTION MODEL AND IT WORKS PRETTY WELL BUT I IF YOU WANT TO REALLY CONSTRUCT THE SPEECH SIGNAL OR THE YOU NEED ALSO THE PHASE SIGNAL WHICH IS IN UH SOME SENSE QUITE SIMPLE FOR VOICED SPEECH SIGNAL SAY BUT S UH THE PHASE NO YOU AC IT'S A PHASE OR YOU CAN ENCODE IT LIKE A CARRIER SO THE CARRIER IS IF YOU KNOW UH AMPLITUDE MODULATION RIGHT YOU MAY SEE SOMETHING LIKE THERE IS ONE COSINE WHICH IS UH VERY WOULD HAVE QUITE A F RIGHT OKAY SO IT'S NOT NECESSARILY PHASE BUT IF YOU'RE USING SOME SORT OF SINUSOIDAL CODING IT'S PHASE YEAH YEAH SO THE THIS IS THE SIGNAL WHICH YOU ALSO HAVE TO SOMEHOW ENCODE OR TRANSMIT FROM A CODE OF THE DECODER IN ORDER TO RE SYNTHESIZE IT RIGHT SO THE S THE SPECTROGRAM W WHAT SORT OF CODING DO YOU GET SO FAR FOR THE NO NO NO NO F F YEAH YEAH YEAH YEP WELL IT'S UH JUST A LINEAR PREDICTION CLASSICAL WAY I MEAN OH OKAY W WELL IF YOU WANT TO SEE IT IN MORE DETAILS I MEAN IS IT IS IT UH ID DO YOU HAVE ANY SORT OF M IDEA OF WHAT SORT OF BAND WIDTHS MAIN BIT RATE WHAT IS YEAH GOOD SO WHEREAS WE ARE WHAT WE ARE NOW IS LET'S SAY SOMETHING LIKE ONE POINT TWO KILO BITS PER SECOND FOR UH THAT HILBERT ENVELOPE IS IT'S AGAIN A ROUGHLY ESTIMATED SOMEHOW BUT WE STILL KNOW THAT WE CAN GO DOWN AND RIGHT EXACTLY YEAH I DON WE ARE USING LIKE FIFTEEN BANDS RIGHT BUT THEY ARE FIRST THEY ARE INTER OH WELL INTEGRATED INTO FIFTEEN BANDS USING OH CLASSICAL WAY LIKE IN M. F. C. C. S OR IN P. L. P. YOU JUST APPLY SOME THOSE UH TRIANGULAR WINDOWS OR SOMETHING LIKE THAT IN ORDER TO TO GET A LI REALLY LIKE JUST FIFTEEN BANDS RIGHT AND EACH BAND IS THEN PROCESSED INDEPENDENTLY SO FOR ONE BAND WE MORE OR LESS HAVE W LIKE W ONE HUNDRED BITS PER SECOND FOR HILBERT ENVELOPE RIGHT RIGHT RIGHT YOU YEAH YOU CAN JUST RIGHT RIGHT RIGHT YEAH OKAY AND THAT'S WITHOUT DOING ANY SORT OF UM PREDICTION OF WHAT THE MISSING BANDS MIGHT BE RIGHT YOU JUST LEAVE THEM OUT I MEAN YOU YOU SHOU YOU COULD BE ABLE TO DO SOME SORT OF CODE MISSING DATA SORT OF BAYES STUFF YEAH THERE ARE MANY THINGS WE WOULD WOULDN'T AT ALL BUT YEAH EXACTLY BUT NOW WHAT I R REALLY TRYING TO DO IS SOMEHOW APPROXIMATE THAT UH CARRIER SIGNAL TO DO SOMETHING WITH THE CARRIER