DE102006048295B4 - Method and device for recording, transmission and reproduction of sound events for communication applications - Google Patents

Abstract

method for stereophonic recording, transmission and playing sound events for communication applications in the telephony, with headphones for each Participants provided and microphones are present, characterized that every ear area each participant a spatially close, but no feedback Connected combination of one earphone or one earphone and one from each one microphone, whereby the real, binaural recorded on the head of each receiving participant in their reflection, diffraction and resonance related environment in the form of corresponding stereophonic sound and sound images to every other participant about one transmit two-channel connection becomes.

Description

State of the art

The The invention is based on a method according to the preamble of Claim 1 and of a device according to the preamble of Claim 5.

On the field of remote transmission of listening events, So in particular mobile telephony, are already a variety known by proposals, the telephone connection, mainly to improve speech intelligibility, but also for a better identification of the respective conversation participant for example, to be interpreted in a somewhat stereophonic way in conference circuits or at least to simulate a kind of stereophony or after all To provide means, such as optical display devices, the one such identification by the other participants in the conversation enable.

As a prior art to be considered, from which the invention proceeds or which may be of general interest in this context, reference is made to the following publications: WO 98/42161 A2 . US Pat. No. 4,088,849 . EP 0 724 352 A2 . DE 40 41 319 A1 . EP 0 358 028 A2 . JP 022/7100 AA . DE 100 20 857 A1 . JP 06268722 AA . DE 37 37 873 C2 ,

In the WO 98/42161 A2 takes place the telephone transmission of a three-dimensional sound event in that before the participant (s) - in connection with a personal computer - two microphones are arranged at a distance from each other, wherein the distance corresponds approximately to the width of a human head. Preferably, the microphones are arranged in artificial ear shapes, as in general the whole arrangement should resemble or simulate an artificial head. To reproduce the stereophonic signals received in this manner from the respective opposite side, loudspeakers arranged on both sides and thus completing the construction are also provided at a distance from one another, furthermore a multiplicity of special filter and compression circuits which are used at certain transmission frequencies are required, for example to compensate for the double cavum conchae function that results when the signal is first picked up by a dummy head construction and then passed to the listener via the speakers.

Despite this considerable circuit complexity, the device is after this WO 98/42161 A2 most likely to be referred to as participant-neutral, because in the recording the environment of the artificial head is transmitted and a personal identification at least more difficult, is actually excluded from the conception. Here, too, the headphones, which are merely supplemental for use by the respective person receiving the transmission, do not help further, as this inevitably eliminates one of the cavum conchae functions, which again, as also mentioned there (page 9 below), an adaptation and Complication of the proposed transmission filtering functions, and insofar as the basic concept as a whole is away from the present invention. In fact, at the WO 98/42161 the attempt to introduce a personal transfer will lead to a distortion of the whole room.

In binaural recordings, especially in a free environment, not having to carry around with one of the usual art heads, is in the US Pat. No. 4,088,849 the head of the wearer itself is used for a possible recording function by externally attached to a pair of headphones worn by the receiving person - the headphones are, as usual, connected to each other via an elastic clip - artificial ear simulation forms are grown, the microphones record. The recorded signals are fed to a tape device, the headphones are used for the simultaneous control of the recorded audio events. The carrier is thus his own artificial head, with outer simulation ears. Indications of a remote transmission of signals are not recognizable.

Another way to identify participants in a telephone conference call, in which the stereophonic signal transmission is not taken into account, shows the EP 0 724 352 A2 , A digital telecommunication exchange contains a table unit with identification data of all subscribers. Whoever speaks loudest, is automatically switched through and there is a corresponding optical identification connected to the devices of the other participants, which points to the person speaking.

In another context, namely a system for video and audio communication, such as for distance learning via satellites, a randomly operated microphone switchover is also known per se. DE 40 41 319 A1 ,

In order to achieve a better speech recognition in a stereophonic remote transmission of auditory events, it is already known ( JP 02217100 AA ), to provide an additional central support microphone for voice addition, which is switched on when the voice of the speaker exceeds a predetermined threshold (see abstract).

Finally, in order to increase the quality of information of conversation participants, reference should be made to the possibility of merely simulating a stereophonic transmission ( DE 37 37 873 C2 ), in which the two a binaural signals supplied to a hearing person via headphones or earphones are additionally provided with distance information and in particular direction information on the basis of special filters (eg high passes, low passes, delay elements, all-passes and the like). This makes it possible, by appropriate adjustment of the filter, the different conference participants assign different listening directions, which can significantly improve the speech intelligibility for incoming call participants, eg in Störschallerfüllter environment. In this respect, such "stereo" telephone connections, for example for mobile call or conference participants, are aimed at simulating a "stereophonic room" from the corresponding terminals for the purpose of selectively allocating different listening directions to individual conference participants or providing stereophonic space from those at the telephone connection to simulate participating terminals with the purpose to distribute the votes of the individual Konferenzteinehmer selectively on different listening directions.

In a similar direction of the application of a stereophonic simulation, but for a mobile telecommunication unit and Microrecordplayer, the DE 100 20 857 A1 In other words, for a so-called mobile phone with MP3 player. In this naturally binaural headphones or earphones are naturally provided for the here usually high-quality stereophonic music enjoyment, furthermore at least one, preferably a plurality of microphones, which are arranged in a so-called head / auricle sounding / - Aufspanneinrichtung, namely a so-called headset. The headset is disconnected from the mobile phone unit and wirelessly connected to it. It is this wireless connection that involves a necessarily stereophonic / two-channel analog-digital as well as a digital-to-analog conversion per transmission direction (see p. 2, Z.20-30 or 39/41). Obviously, these explanations, however, only relate to the so-called wireless "Bluetooth" connection means known extensively in the case of mobile phones between the actual device and the headphones and microphone on the headset. An essential moment with such mobile telephone units with MP3 Player sees the DE 100 20 857 A1 recognizable in the combination of such MP3 mobile phones with electromagnetic shielding means to tame at biological as high field strengths biological effects / stress (Sp. 1, Z.35-46). For this purpose, it is proposed to arrange natural quartz sand or rose quartz, which in turn is again introduced into elongated copper / plastic pipes, into pipe systems layered out of iron / copper sheets, whereby the stress reactions / stress reactions of "electrosmog" are reduced with regard to the body reactions (Sp , Z. 47-54).

Because this DE 100 20 857 A1 It should be noted, moreover, that clear instructions on technical action can not always be found with the requisite desirable clarity, in that true stereophonic transmission measures are not envisaged in the telephonic transmission, unlike the aforementioned Bluetooth transmission between the device and the headset - This can be seen, for example, from the note in column 2, Z. 54-59, according to which the sound reproduction reaching voice / audio alternating signals are mixed individually binauralrichtung filtered in selectable different listening directions. In this respect, this directional filtering corresponds to the above-mentioned high-pass / low-pass and the like filters for adjusting the hearing direction accordingly DE 37 37 873 C2 , also in the sense of eligibility; With true stereophonic recordings, of course, a directional selectability of the respective sound source is excluded and not even intended.

In particular, in order to be able to receive as a subscriber via a telephone connection high-quality music products, is in the JP 06268722 AA a multiplex receiver circuit is described, which splits the input signal to be received via the telephone line into a left and right loudspeaker signal and processes it accordingly.

Finally, the EP 0 358 028 a digital time-division telecommunications switching system with a voice memory, which is used as a conference memory and extended by additional memory cells. In this case, a return loop from the output of the speech memory is placed to the input. Stereophonic considerations are not considered.

Of the Invention is based on the object in a stereophonic telephony system to realize real person-bound speaker functions, so that beside the excellent speech intelligibility also a perfect identification of each speaking person possible is.

The invention solves this problem with the characterizing features of the main claim or the first device claim and has the advantage that both first or in the case of so-called conference calls - regardless of whether these go from several participants located in a common room to one or more participants or go out from different places - all participants in the situation ver are set to conduct and receive conversations with the other participants, as if they are in the same room with them, so with all the otherwise occurring reflections and diffraction functions, which also normally occur when one with a counterpart in one certain environment leads to a conversation and what one is used to in a natural way anyway. For this reason alone, this leads to an almost astounding improvement in speech intelligibility, compared to the narrowband, practically pure voice frequency transmission that is still practiced today without the liveliness of the natural space, the manifold diffraction, resonance and reflection structures that alone on the Finally, the complex superimpositions generated by the human body, ie, upper body, shoulder, head, etc., and then finally to the two-channel, stereophonic transfer function entgleichchend the invention.

By the binaural sound detection in the ear area of each conversation participant arise so natural head-related audio images as to be transferred Stereopanorama that correspond to reality, i. every participant takes over each of his Headphones or earphones the head-related environment true in which his interlocutor currently located, including of which, in this and only in this environment impact Voice, so, as already mentioned, equipped with all the reflections, diffractions and resonances, which makes or influences this environment. The speech intelligibility is therefore excellent because it does exactly what the language-processing people do Brain regions of every human being from the beginning of speech development at all used and adapted, namely the full sound of the language in the resonance, diffraction and reflection spectrum the environment and one's own body, and not the cut-rate frequency, thin, practically dead sound previously practiced telephone voice.

For this belongs basically another phenomenon, which is that it with the means of the invention also manages to effectively eliminate noise, therefore, because these are well located by the respective, just listening participant and thereby selected a priori as not belonging to the conversation can be - even this is a special skill probably not just the human ear or brain and shows up in fact, especially in the context of such contexts liked mentioned "cocktail party effect"; despite the through the frequent Voiceover resulting noise those present are able to work almost without any problems, even at some distance to hear exactly the speaker and to focus on those they are interested in All others equal or even loud incoming audio events become conscious without Action suppressed or no longer the understanding aggravated aggravating level. Exactly this "natural" phenomenon offers the invention by the realization of the subscriber head related stereophonic space, so that in particular Also in conference calls of any kind so far natural entertainment with immediate orientation to the respective conversation partner possible is.

to Further deepening just this aspect of the invention is on it pointed out that it means the full-stereophonic transmission pefekt succeeds in leaving the participant on the other side own local Soundworld in all perceptible timbres and sound sequences like to watch a radio play to let go, whether in a New York jazz cellar, at the Carnival in Rio or on a beach with surf and gulls screaming located.

To belongs to this point of view also the possibility the one to send, the local Sound and speech events containing stereo signal more own sounds or subordinate or mix sound sequences, for example in their dynamics attenuated, the conversation is not disturbing Music, songs or whatever else on the mp3 player or ipod, you just for a conversation used, is located. The summary of such various functions such as telephone, MP3 player, calculator, game machine and the like. in a small apparatus Yes, nowadays are the general state of the art.

The Today's technical development, also and especially the fast telephone data transfer, allows a two-channel transmission easily in corresponding data packets, both wireless, e.g. to and from Net as well as in the network itself, so that under consideration may be seen in isolation Also known electronic components such as decoders, encoders, interfaces u. Like. A stereophonic telephone connection according to the Invention is always realizable.

By in the subclaims listed activities are advantageous developments and improvements in the main claim or in the first device claim stereophonic telephone connection possible.

drawing

embodiments The invention are illustrated in the drawings and in the following description explained. Show it:

1 a schematic representation of a first embodiment of the present invention in the form of a stereophonic telephone connection with two participants at different locations and

2 a second embodiment of the invention, in which a first subscriber via a stereophonic telephone connection with three other participants who are located together at another location, in the manner of a conference call in connection.

Description of the embodiments

Of the The basic idea of the present invention consists in a telephone Telephone connection, independent of whether this is now over altogether Cable or completely or even partially wirelessly, the real one Environment of each conversation participant in the form of head-related images the respective opposite side, whereby each participant at least over a stereo microphone and stereo headphone or earphone features.

1 shows what is meant. Participant Ao, whose head with 10 is headed over a stereophonic telephone call with subscriber Bo 11 connected. Each participant Ao and Bo has adjacent to his two ears or within the ears, in any case so in the ear area, each one combination 12 , each consisting of an electric sounder, usually headphones or earphones 13 and one microphone each 14 for then total stereophonic recording or playback of auditory events. The microphones 14 Therefore, they are adjacent to or possibly also within the ear areas, so that they can cooperatively stereophonically accommodate exactly the so far referred to as head-related listening images, which also form the actual acoustic environment of the participant. It is understood that in a suitable manner for echo- and feedback-free connection or arrangement of the microphones with respect to the sounder also present at this point, so ear or headphones, care must be taken so that the respective caller does not his own voice again gets retransmitted. Such, a feedback freedom assurance acoustic insulation is easy to realize for the expert.

As mentioned, the sound generator can be of any nature, eg supraaural headphones or preferably also earphones, so that it is possible to dispense with head-mounting carrier arrangements. In any case, for amplification and equalization of the signals obtained or to be heard the two microphones (ie the one stereo microphone) and the two sound generators 13 each amplifier / equalizer blocks 15a for the sounders and 15b downstream of the microphones, which are on a two-channel interface 16 work. If one grasps the combinations assigned to each participant 12 as a first module, then form the amplifier / equalizer circuits with the associated interface 16a a second assembly 17 , which in turn is wireless or wired for two-channel transmission to a downstream communication terminal 18 is switched, which in turn, in turn, wireless or wired, ensures the two-channel signal transmission to the network.

Independently of, whether external, so supraaural open or closed headphones or in-ear playback systems be used, always arise head-related, stereophonic telephony signals, in the case of earphones, where then the microphones attached or otherwise assigned are even a part of the auricle as a reflection, diffraction or resonance body yet would get what the naturalness complementary to the transmitted signals would improve.

Due to the considerable possibilities that today and probably also in the future, the ever-advancing technical development in terms of integration of components and increasing miniaturization, there is a particular advantage through the use of earphones also because in this case the miniaturized combinations 12 each of an earphone and a microphone also waive wired leads and therefore different from the representations in the drawing can be realized; with a common earphone and microphone supply battery for each combination 12 and a common ultra-short distance transmitter to the downstream assembly 17 a comfortable and comfortable fit is achieved, no wire connections dangle around the participant's head, and there are no inconveniences except for the microphone and sounder combinations that are easily plugged into each ear. In any case, the earphones, as any user of an MP3 player, such as I-pod white, particularly advantageous in the sense of so-called open headphones, so do not complete the user against his acoustic environment, but allow any desired type of communication.

In themselves, the respective, explain in the modules 12 . 17 and 18 contained circuit blocks from the specified in the drawing label for the skilled person by itself; the equalizer blocks are used to signal normalization, which may be necessary if the respective participants in the conversation use different headsets or other sounder and microphone systems or only with wireless earphones from microphone and Earphones work so as to achieve comparability with the other signals. This can also have a meaning, depending on where the microphone sits, but also because of the desired feedback freedom. Thus, the equalizers provide a compensation to finally come to a downstream standard interface.

For the sensible or desired separation of the individual modules are the interfaces 16a . 16b . 16c in accordance with high-quality two-channel training required wired or wireless, so by radio to work on the associated interface of the following module.

Basically but noted that the in the drawing made allocation and assignment of the various Modules or circuit blocks mainly a better understanding and the vividness of basic functions according to the invention, it is understood that not least because of the technical progress achieved or another purpose in assignment and training, also another summary of Circuit blocks, as well quite differently designed and interconnected signal processing circuits are realizable and can be used.

2 shows an advantageous embodiment of the invention to the effect that at least on one side a plurality of participants B, B ', B''are present, which are in this case in a common room and wherein each of the participants B, B', B '' a Headset or the combination 12 from microphone and sounder carries at each ear area, as well as the participants A, with each participant B, B ', B''is two channels connected via the network. For this purpose, each of the in 2 participating communication terminals 18 ' - Also in the area of the subscriber A other conference participants A ', A''could be present - a modification in that in the two-channel input interface 16b ' an additional recording function selection circuit 19 is provided. This has the task of automatically deciding in a first variant, which microphone pair which conversation participant on the output-side network interface 16c ' switched and thus released for transmission through the network; This can be done, for example, by detecting the dynamics of the speech signals that are generated by one of the participants B, B ', B''at a given time or which of the participants speaks at all. The recording function selection circuit then blocks the microphone signal transmission from the other participants, but of course not the sound signal transmission to the individual sounders of each other participant.

For this belongs also the possibility that of the respective person speaking outgoing speech and ambient signals on the Plant, so on electrical ways back or better the sounder the other participants in the same room complementary, so to speak supplied even if they can hear the voice signals directly through the airspace. Actually yes not exclude the existence direct listening aggravating or due to sealing completely preventing sounder Find use.

If, at any given time, the first subscriber speaking and appropriately connected is silent here of the triplet, eg subscriber B, and another subscriber, say B ", interrupts the word, then the record function selection circuit of the communication device switches 18 ' Subscriber B '' in this first variant automatically, so selbstätig on the network interface 16c ' , However, this does not mean that subscriber A at the other end of the network would then necessarily only perceive the respectively last admitted conference participant; indeed, of course, he hears, albeit according to the particular spatial conditions in a weakened form, all the other participants on the stereo microphone of participant B '', so that in this case, the full stereo panorama in the three-dimensional surround sound for participants A results, practically so as if he is in a common room with the participants B, B ', B''.

It is possible, additionally or instead of automatic switching these manually, so to arbitrary activity interpreted so that e.g. the participant wishing to speak, one Button, which is also directly in its respective access area can be arranged, actuated and so switched from the recording function selection circuit to the network becomes. Mute buttons, such as a discrete briefing be guided should, can also be arranged.

It is also advantageous to arrange in the area of the recording function circuit or else in any other suitable place a control and indicator lights, LEDs or the like. Which indicates which of the call participants the Aufnahmefunktionswahl circuit 19 on the output side network interface 16c ' has switched. Since the other circuit components of the conference circuit variant of 2 the circuit blocks of 1 need not be further discussed; It has also been refrained from re-integrating reference numerals of the circuit blocks already discussed above with their functions in the drawing.

Regarding the Signal and channel decoder or encoder in the communication terminal is still added, that the Signal decoder digital / analog conversions or vice versa carry out and bandwidth determinations (bandwidth of the signals is included) at least 3, 4 kHz / 8kHz / 16kHz), also for the lowest possible Group differences, with coherence between the channels in the coding / decoding possible is not changed, while the channel decoding and encoding suit the overall signal for the particular network makes, where at this point the stereo signals and all others Signals are already nested in a signal, so to speak. Further To take care of These channel switches are redundancy and error detection. There are the one-way running times including signal coding / decoding and transmission ideally in the range of less than 150 microsec., so that a timely, undistorted signal transmission guaranteed is.

On A further advantageous embodiment of the invention will be discussed later, which consists of an additional one Single microphone preferably in the vicinity of the mouth of each interlocutor, which either - to better understandability for example - as a kind of support microphone the stereo signal, mixed or alternatively, the stereo signal of the binaural microphone pair can also completely replace. Man returns thereby retained in the field of conventional monotelephony over binaural headphones back - could this possibility but use, if for certain reasons, possibly even of Beginning, on a stereophonic transfer of Environment information is omitted, so this is no longer important or desired held, or, e.g. in the course of a conversation, on such a mono operation on both sides wants to be switched. This can be done of course, too Bandwidth for the one to be transmitted Save signal and corresponding costs. Appropriate measures can be easily integrated into the existing software configuration supplemented by a simple switch operation from the participant side.

It understands that all in the description, the following claims and in particular in the Characteristics shown individually as well as in any Combination with each other can be essential to the invention.

Claims (11)

A method for stereophonic recording, transmission and reproduction of sound events for communication applications in telephony, wherein headphones are provided for each participant and microphones are present, characterized in that each ear area of each participant a spatially close, but feedback-free combination of each ear or headphone and is assigned in each case to a microphone, whereby the actual, binaurally recorded on the head of each receiving subscriber in their reflection, diffraction and resonance behavior related environment is transmitted in the form of corresponding stereophonic sound and sound images to each other participants over a two-channel connection , Method according to claim 1, characterized in that that in the Case of conference calls each in a same room resident interlocutor either by automatic switching, effected by its own interview process or by an arbitrary actuated Switch over selectively a pick-up selection circuit on a connecting all participants Network is switched. Method according to claim 1 or 2, characterized that at several participants in a common room in a conference call each of these, at the moment non-speaking participants at least the call signal additional to the natural acoustic room transmission over a electrical feedback loop, about in the communication device, too their binaural headphones or earphones supplied becomes. Method according to one of claims 1-3, characterized that in addition to the stereophonic environment and voice transmission as desired by every conversation participant Sound and sound sequences (musical pieces, songs) in the respective used stereophonic telephone device (cell phone with MP3 player) stored are to be transferred. Apparatus for carrying out the method according to one of claims 1, 2, 3 or 4, characterized in that for recording, transmission and reproduction for each ear area of a telephone subscriber (A, B; B ', B'') a combination ( 12 ) from each a sound generator (headphones or earphones 13 ) and one microphone each ( 14 ), with each combination ( 12 ) Sounder and microphone are arranged in close spatial relationship while avoiding echo or feedback phenomena for simultaneous binaural recording, transmission and reproduction of true stereophonic sound and sound images, including the environment and personal reflection, diffraction and resonance behavior. Apparatus according to claim 5, characterized ge indicates that, for the two-channel further processing of the binaurally obtained or received signals for each sounder and microphones separately two-channel amplifier / equalizer circuits ( 15a . 15b ), further signal and channel decoder and encoder circuits are provided. Apparatus according to claim 5 or 6, characterized in that between the individual signal processing circuits, depending on their assignment to each other two-channel interfaces ( 16a . 16b ) as well as a network interface ( 16c ), with wireless or wired transmission between the interfaces or between network interface and network. Device according to one or more of claims 5-7, characterized in that in the case of several participants in a common room a two-channel multiple interface ( 16b ) is provided, with which the individual call participants, after appropriate Eigensignalaufbereitung, are connected and that a recording function selection circuit ( 19 ) is provided for automatically or arbitrarily operable switching recorded microphone signals for forwarding to the network of one of the participants (B) to another (B ''). Device according to one of claims 5-8, characterized in that a first, the two ear-area combinations ( 12 ) from one microphone each ( 14 ) and a headset or earphone ( 13 ) comprises a second circuit group consisting of amplifier / equalizer blocks for handset or microphone ( 17 ), which is connected to a downstream communication terminal ( 18 ) via bilateral assigned two-channel interfaces ( 16a . 16b ) is connected wirelessly or wired, wherein the communication terminal ( 18 ) Signal decoders and encoders as well as channel decoders and encoders and in the case of conference circuits to an input-side multiple interface ( 16b ' ) a recording function selection circuit ( 19 ) with control and indicator display for automatically or arbitrarily actuated connection of the respective speaking subscriber to the telephone network. Device according to one or more of claims 5-9 by a circuit arrangement through which the stereophonic communication to a desired Switch time on both sides to mono mode. Device according to one or more of claims 5-10 through a third, near-mouth support microphone to the needs-based speech mixing to the transmitted stereo signal or to enable Mono operation according to claim 10.