thank you very much and a um it's you also see yeah i'm not the first author of this paper but in our case i must say for to T such that this cannot be here to date because see his family has been in by a second door to two weeks ago so he can't be here um and i'm working at the international audio lab or to recent a in which is that joint institution of um the university of a you know back and the problem of a institute for integrated circuits what's the motivation for the work i'm going to present here is that you often do in music production use a lie on mixing prerecorded material samples and um you also need to at that these samples frequently two different to musical context then the context they were recorded in so in in some cases you might need to key mode conversion this means major to minor or vice versa and they the a algorithm for four enabling this task as been presented um in previous conferences this this is called mode clock modulation vocoder um it's some what's you to put to this task but um we also found out that device special enhancements necessary in order to address special requirements for this application so i first want to um give a short overview on this model walk accuracy which performs the single pass and is in a block wise processing which is shown in in a block diagrams here it does first uh signal adaptive band-pass filtering which is aligned with spectral center centres of gravity means we first of the um if T analysis yeah a dft analysis and from the dft spectra the um centres of gravity in perceptually adjusted then uh determined in the band it's uh just it's so they are this decomposition is flexible so from these centres center frequencies um and the around centre center frequencies to construct a bandpass filters and i in the yeah done in the frequency domain and in inverse uh dft T get back for each bandpass signal a to a time domain signal and um this time domain signal bandpass signal is then and lies with and am and fm and that this this so you basically you have the carrier frequency which corresponds to the centre of gravity of this special frequency reach and a uh the F signal which gives the um instantaneous frequency offset quite um relative to this carrier of frequency and you get um get the instantaneous make me to do M P chewed in the A M component and then you can close to the signal in this modulation domain for example you can change the carrier frequencies and still maintain that uh fine temporal structure um by keeping the A M and the F it's um in the synthesis you have to combine the a if M component with the maybe mode you modified um carrier frequency you have to somehow one the different um components from button block to the next block because it's tempered blocks sets it before um or just and yeah and um you to uh and overlap it processing of the am and the F M or frequent instantaneous frequency signals in order to get continuous um parameter and then you two the synthesis and at up um all the sickness from the different bands you had decompose the signal into four so this is the basic structure of the modulation well coder but do you to the structure with the relatively long blocks in the dft analysis you still the um miss some of the um signal uh characteristics by this processing um and this is one of the parts we we address by the enhancement and this the first of these enhancement was the so-called envelope shaping i means temporal envelopes of with in the uh dft blocks might got get um lost or distorted because you um can lose the um this uh to to dispersed and you can whose face a relations between the different tone and this would could cost the temporal smearing of transients and in this case it's better to use then explicit a temporal envelope and you get access to the parameters of these um of this temporal in below but doing an lpc analysis in the frequency domain because correlation in the frequency domain corresponds to multiplication in the time domain this means with it at coefficient you get from from lpc analysis along the frequency axis you get parameters you can use for a um getting and time function you could could say at time response yeah but you can then it at the end a might apply to to get back the temporal and middle this what is done with this read looks these are the um enhancements what the envelopes um in other enhancement the enhancement which is necessary once you um start modifying spectra components is that you have to take into account that um music a sounds are not normally consisting of a fundamental into a lot of harmonics the tone and um you should keep this in mind when you modify frequencies so the overtones tones are um quasi harmonic on uh the yeah frequency scale which are you normally integer multiples of the fundamental frequency on you team integer multiples um on the other hand to musical intervals are based on a logarithmic scale and um now it's a question when you modify frequencies in which way you should modify them um or and of course we want to modify them in the the based way for for the a for what we intend to to for example for the transcription and we have to consider a this because if it's a five it if it's an over of one fundamental to frequency you which have to modified in accordance with the fundamental and not according to the musical scale the the um if it would be and uh signal toll on and that and then other um part of the of the um skater so yeah in this leads to some kind of ambiguity when you get one told in just look um look at it on its own so that's why we have to um get some addition interpretation to find out whether it's uh fundamental frequency are if it's an overtone or uh a harmonic component of uh a more complex sound structure this is just an example of um how in pulse of this key is uh can match the um how morning and um just one example of uh to pick out could be the number five which is five times the uh a fundamental frequency of one to alone could be also um and now that in which is a major it a parts am in this in this diagram that the at might of of tapes and not taking into account so so we you can have um some ambiguities between a second and also the for um harmonic which would then be just put of op tapes and so on so that's why you get kind of an be treaty with um over to ones and music scores and that's why this second enhancement at been added to model clock which is so that hmmm which is called harmonic locking so um is a set before the to estimated fundamental as have to be mapped directory and then you have to um decide for a the components if it's a um oh but then it has to be lot to the transposition of its fundamental just an the processing yeah you decide um for money told if it's um not to another frequency of bits as be transposed on it's all and by this which yeah um just on either it transposition of them G D node based mapping which is done for the fundamental frequency yeah are it um done a transpose according to the to its fundamental if it if it's locked as up apply uh indication here it's not non locked then it's is locked in to test to be looked to the fundamental frequency and its map now we come to the um listening test methodology it's a to a difficult task if you to um this kind of transcription so we uh selected me D samples which we first at in the original domain and we did me transcription to obtain um five which we could then yeah put into the test so these but it is uh transcribe um reference signal which is done by T and then uh transfer to a bay five and on the other hand hand we get the original wave file and be processed it um to to with the transcription and then we can compare the to and we have different versions three versions of of the more folk and one reference transcription system job also present yeah um there's one commercial system available which is the direct note excess in the middle line at each up by a mini and this is available since autumn when a two thousand and nine and it also allows selective editing eating of polyphonic music but it performs a multi-pass pass analysis and it doesn't automatic decomposition into notes and um a heuristic classification rule but it also can be used to perform this scheme mode clean key mode conversion and so that's why we also try to um compare our approach with this one these are the the um items we used um problem with to P a project we use some different signals and different midi files is the set before trash shown here and this B try to get some variety of more complex orchestral music and some more um solo instrument hearts so cup quite a mixture of complexity of of um content these were the results of "'em" so called mass for a test that we don't want to go too much into detail in this test we have a a um normally you hidden reference is um i don't you know to by one we have um uh so quite reference which is just uh low-pass pass filtered signal which just numb do you know to by number two and we have the more work the origin and what block the more rock um is number three what work with the harmonic locking is for and mark work with the a harmonic locking and D um envelope shaping it's five and six is the the N A you the rate um this system be compared to um but not first we want to see how um oh enhancements work in T V C um um for this one example B that um a difference between four and five this means the addition of envelope shaping what's see a for the key tar um the key top once it's a much clearer a and so somewhat preferred by the listen and um here i um we have the difference but a a difference between uh the original remote walk and that mote work with someone it locking with the which um delivered but the for a no signal we also see that uh in in most of the cases um the D N A perform better and um i can make first summer right these sides here that the harmonic locking really improve the term the the envelope shaping also improve the trends in parts but you know was rated better for five out of seven items and um the rating could cover different aspects of this sound change which but was performed here like a natural sounding artifacts on melody or car transcription errors but tampa the preservation or pages um and it is nice in many reported to trend for transposition error us um in the in eighty and uh tampa problems from what talk so we made an additional test which was the formant preference test when these main quality aspects to find out more if this is really the case for this um yet twelve expert listeners mean post technical a musical background and we had now with them the extended model talk and compared it to the N a and um we also found out in the first test that is unknown mailer T which is a a transcribed version of the original the um me D is somehow hard to um to great for for people so we did it the other way around we did the transcription with me D integral tries transcribe it back to the original um score um with a right for with our egg for for signals which are shown yeah also orchestra and some mixture and P know and now we we put this five in the in the preference test and and the outcome was quite clear in the sense is the people that reported before in that's there was a quite the uh preference for uh the melody transcription for more walk which is shown yeah what focus all that the it left side and in these are the results for a for the a transcription music transcription and he uh are the results for time of the which uh show the clear preference for for the D N A i can play an example a can play all the five to get a yeah and short versions in the all that is they are shown here first your reaching a a a a a a um i a i um a a a um a a um i think the some problems in the in the music transcriptions in it in a a a number uh a pressing this listening conditions yeah so um not example is this is the piano no used to have time i play also the um this device here uh um uh uh uh uh uh uh uh um uh uh uh uh uh uh uh um oh uh uh uh oh uh um uh uh uh uh uh um uh uh "'kay" so um just a short summary um we have down now the what work for selective trends position of pitch which is capable of real-time processing and which can put use trends ends and uh also improves the time the by how money clocking and it's um referred over the commercial system in the in terms of transposition position of the melody T but it you know a the um prefer in time proposed preservation so and in maybe in general the the both of the systems were and the range from fair to good so there's room for improvement but the already a somewhat use of yeah the system thank you we questions one question i had as willis was trained listeners was goal years or where there um um for the for the preference test it's it were a of people who were also yeah i had some music background to stressed um quite important for this uh a time to the um grading let's say but they weren't signal processors are not special to a golden yes no and you questions one harder question well would you like to do me if you had all the signal processing power and all smart you could do what would you like to do to oh problem um i think can be that they can be made a bit more complicated if you you can imagine that you have total ones which are a mixture of uh maybe harmonics and find a mentor the frequency and so on a a at different harmonics of different tones which match and the on the grid so then of course the decomposition is much more complicated and it and of course for this you would need to quite a more um up station um so i think this would be one of the ways of a a a a a a further improvement could be achieved a because the see anything else thank okay can use a microphone on your bullet point up there about a reproduction of transients improved by lpc based envelope shaping could you comment on that what that is yeah the it we use the lpc parameters and um be obtained in the frequency domain and apply this is a time envelope in the time domain this is what i showed with the with the rates blocks and uh when overview diagram thank you