A kind of vehicle-mounted sound mixing method and its deviceTechnical field
The present invention relates to automobile speech field, more particularly to a kind of vehicle-mounted sound mixing method and its device.
Background technology
In recent years, the software development travelled with various types of vehicles, the audio provided by in-car multimedia driver is neededAsk and gradually increase, have based on recreational multimedia audio signal, there is the prompting audio signal driven based on navigation, have based on peaceAlarm audio signal that full auxiliary drives etc..When being played to these a variety of audio requests simultaneously, because vehicle at most only hasFixed four loudspeaker output, it is general to be exported after being handled by the way of mixing, such as it is based on multimedia recreation audio, hybrid navigationPrompting or safe driving prompting mode, but similar navigation hint points out this kind of audio signal mixed to deposit in itself with safe drivingIn the big problem of noise, and only play, for a long time substantially without asking, if opening hybrid channel for a long time, make in a short timeThe multimedia recreation signal for obtaining normal high-fidelity demand originally receives the noise jamming of hybrid channel, influences the sense of hearing of driverEnjoy,.
Existing settling mode is to carry out volume processing to multichannel so that the volume of output relative comfort, such asCN201610276920.5, but this method can not eliminate the noise jamming of audio mixing passage, in the period that need not be mixed,The volume of mixed audio is reduced, the signal amplitude of multimedia audio is improved, so as to improve the signal to noise ratio of multimedia audio so that make an uproarThe relatively useful audio of sound weakens, but this mode easily causes multi-media signal distortion caused by amplitude is excessive.
Another method is by way of software controls audio mixing channel switch, when second audio request opens audio mixingIn the case of passage, it can just be opened by software, that is, in the time for ensureing the free time, the noise jamming without audio mixing passage, this sideThough case in actual applications, can increase software logic complexity, also pole has from the noise jamming for acoustically reducing audio mixing passageThe stability of system may be influenceed, this method is judged by software in addition, certain delay can be brought, this delay to mixThe time that sound passage is opened does not catch up with the time of the broadcasting of audio, often leads to audio and has finished playing, is also not turned on mixingThe situation of sound passage so that driver is merely able to the content of mixed audio the need for hearing a part or not hearing completely.If in addition, mixing voice is not from system schema itself, but by the direct introduction system of external equipment, then can notHandled by software-controlled manner.
The content of the invention
The problem to be solved in the present invention how is solved in existing vehicle-mounted audio mixing, it is impossible to done while existing and eliminating noiseDisturb, audio mixing postpones, volume is comfortable, control versatility and simple in construction.
In order to solve the above problems, the invention provides a kind of vehicle-mounted sound mixing method, comprise the following steps：
S10：Set noise floor amplitude；
S20：The mixing voice signal of input is handled；
S30：The amplitude of mixing voice signal after processing and noise floor amplitude are compared, if the width of mixing voice signalValue is less than or equal to noise floor amplitude, then skips to S50, otherwise skip to S40；
S40：Audio mixing passage is opened, the mixing voice signal after processing is mixed with multimedia source of sound, jumped to afterwardsS20；
S50：Audio mixing passage is closed, S20 is jumped to afterwards.
By setting noise floor value, the mixing voice signal of input carries out unified processing, after processing by with noiseA reference value is carried out determining whether noise, and common sound channel noise is general to be walked by process step filter above, so general lowIt is the noise signal of remaining in the mixing voice signal of noise floor value, its amplitude is respectively less than noise floor value, it is impossible to beatAudio mixing passage is opened, otherwise useful mixing voice signal can then open mixing sound passage, by this method, area is not needed not onlyWhether the source for dividing sound is the scheme of system in itself, reduces the complexity of scheme, improves reaction efficiency, additionally it is possible to in sound channelNoise handled.
Step S40 comprises the following steps：
S41：It is more than the mixing voice signal of noise floor amplitude to amplitude, carries out delay process；
S42：Audio mixing passage is opened, the mixing voice signal after processing is mixed with multimedia source of sound, jumped to afterwardsS20。
By carrying out delay process to the mixing voice signal for being prepared to enter into audio mixing passage, it ensure that useful in the signalMessage segment（It is more than the frequency range of noise floor value）Can avoid caused by signal transduction process mixing sound passage open more slowly andA part of useful information is caused not to be mixed into sound channel so that driver can not hear complete information.
S20 comprises the following steps：
S21：Processing is filtered to the mixing voice signal of input；
S22：Processing is amplified to the mixing voice signal of input.
Processing is filtered by the mixing voice signal to input, a part of noise can directly be filtered out, sound is improvedFrequency quality, a part of noise can be amplified by being also prevented from follow-up audio amplification procedure, influence follow-up amplitude com parison to judge.To defeatedThe mixing voice signal entered is amplified, and enables to useful message segment can be understood after follow-up mixing sound by driverHear.
S10 comprises the following steps：
S11：Set noise floor amplitude；
S12：Set upmixed channels.
By setting mixing sound passage, enable to related mixing sound only can be embodied in some sound channel, will not be in full carIt is interior to play, improve the ride quality of in-car passenger.
Step S40 comprises the following steps：
S42：Audio mixing passage is opened,
S43：Mixing voice signal after processing is mixed with the sound channel of selected multimedia source of sound, S20 is jumped to afterwards.
A kind of vehicle-mounted device sound mixing, including signal processing module, detection module, switch module, described signal transacting mouldBlock is connected with detection module, and described detection module is connected with switch module, and described detection module being capable of controlling switch moduleBreak-make.Each module more than by internally directly setting, can originate regardless of audio, directly to audio frequency process, improve audioDisposal ability, in addition detection module directly switch module can be controlled by testing result, it is ensured that the standard of switchTrue property, also improves the break-make speed of switch module in addition, reduces the time that delay is played so that driver faster receives correlationAudio-frequency information.
Signal processing module includes voice filtration module and voice amplification module, and described voice filtration module is put with voiceBig module connection, described voice amplification module is connected with detection module.Two modules can in advance be located to the audio of inputReason, improves the judgement precision of follow-up detection module.
Also include voice latency module, described voice latency module is arranged between detection module and switch module.ProlongSlow module can solve the problem that in detection module the time required to the information closed to switch module, switch module closing courseThis section of process, pertinent audio information advance to up to after switch module can not by and the situation that causes useful information to lose is sent outIt is raw.
The present invention has following beneficial effect：
1. it completely can clearly export mixing voice signal.By the filtering noise reduction process of early stage, and follow-up useful information sectionCarry out delay process so that mixing voice signal to be output can be mixed intactly, clearly be played out.
2. can not need in the time of hybrid navigation prompt tone or safe driving prompt tone, refuse hybrid channel completelyInterference of the noise to multimedia audio, with high fidelity play multimedia music.
3. highly versatile.The audio signal in onboard system or in external system can be handled.
4. it is simple in construction.The present invention's is simple in construction, relatively with existing complex software control method, in cost and dimensionBig advantage is built.
Brief description of the drawings
Fig. 1 is a kind of method flow diagram of vehicle-mounted sound mixing method of the present invention.
Fig. 2 is a kind of hardware schematic of vehicle-mounted sound mixing method and its device of the present invention.
Embodiment
Presently preferred embodiments of the present invention is described in detail below in conjunction with the accompanying drawings so that the present invention a little with feature moreEasily it is readily appreciated by one skilled in the art, so as to make apparent define to protection scope of the present invention.
Embodiment 1
Noise floor amplitude is set first, and a reference value can be configured by the parameter of circuit structure, can also be stored inIn corresponding information storing media.Simultaneously mixing sound passage can also be set, mixing sound passage refer to it is different it is outer put passage, it is in-carThere are 4 loudspeaker, can simply think there are 4 mixing sound passages, the mixing sound passage of setting can be 1 either several.Carrying outDuring processing, the mixing voice signal of input is handled first, the mode of processing can be handled by way of circuit,Also it can be handled also by the software algorithm in microprocessor, specifically include the filtering to signal, be amplified, frequency modulation and noise reductionEtc. process content.After completing to handle the signal of input, then by the signal after processing in real time with noise floor Amplitude RationCompared with, in the case where amplitude is more than noise floor amplitude, mixing sound passage is opened, because amplitude is relatively to compare in real time, instituteOpening and closing with passage are determined according to real-time comparative result, when the amplitude compared is less than noise floor amplitude,Mixing sound passage can be closed at once.It can be mixed into the useful information section after mixing sound passage according to mixing sound passage set in advanceSound, exports the audio of mixing under specified passage.
Embodiment 2
As depicted in figs. 1 and 2, using in-car multimedia source of sound as basic source of sound, the signal that source of sound to be mixed is sent is referred to as mixingClose voice signal.In-car includes audio processing modules and vehicle MCU module, vehicle MCU module, 4 differences of vehicle interiorThe loudspeaker of sound channel, vehicle MCU module is connected with audio processing modules, 4 different sound channels of audio processing modules and vehicle interiorLoudspeaker are connected respectively, i.e., vehicle MCU can control audio processing modules to be operated, and audio frequency control module can be defeated by outsideThe audio entered is handled, and being then sent to different sound channel loudspeaker by related control instruction carries out sounding.Also include thisVoice filtration module, voice amplification module, detection module, Postponement module and the switch module of invention, source of sound to be mixed and filterRipple module is connected, and the output end of voice filtration module is connected with the input of voice amplification module, the output of voice amplification moduleEnd is connected with detection module, and the output end of detection module is connected with Postponement module, and output end and the switch module of Postponement module connectConnect, meanwhile, detection module can be with the break-make of controlling switch module.The output end of switch module is connected with audio frequency control moduleConnect.
Source of sound to be mixed can be connected for a long time in the case of connection, i.e., can send audio letter to the present invention for a long timeNumber, but it is useful message segment entirely not to be in the audio signal that sends for a long time of source of sound, when not producing useful letter in source of soundDuring breath, its audio-frequency information sent should be 0 in theory, but be due to the effect of transmission environment and internal electronic component, usuallyMore noise can be produced.
After the connection with the present invention, source of sound to be mixed constantly sends audio to the present invention, it is desirable to is mixed, waits to mixThe audio of conjunction is filtered by voice filter in real time, and wave filter is specially bandpass filter here, described wave filter modelEnclose for 20Hz ~ 20Khz, after filtering after device, filtering voice will be amplified by speech amplifier in real time, and voice is amplifiedTo suitable amplitude size, detection module will be delivered to after amplification.Detection module is provided with noise floor amplitude, noise floor in itselfAmplitude is specially an amplitude numerical value.The audio to be mixed transmitted in real time and noise floor amplitude are compared by detection module,If amplitude is less than noise floor amplitude, not act, now, real-time voice signal remains able to, by detection module, enterEnter to time delay module, now real-time voice signal will be delayed by output, the time of delay and the actuation time of switch moduleRelevant, when the voice signal output being delayed by, because switching signal is not yet closed, signal will be unable to output；Work as amplitudeDuring more than noise floor amplitude, then controlling switch module is closed detection module so that audio to be mixed can be by openingModule is closed, enters in audio processing modules and carries out the processing of audio mixing.Because time delay module prolongs to real-time voice signalLate, the time of delay and the actuation time of switch module are identical, and the time that signal is transmitted under such environment ignores, instituteEnsure that useful information can be exported intactly.After audio signal is received by audio processing modules, i.e., according to predeterminedProgram carry out audio mixing, and export, complete overall audio mixing flow.
Embodiments of the present invention are explained in detail above in conjunction with accompanying drawing, but the present invention is not limited to above-mentioned implementationMode, can also be on the premise of present inventive concept not be departed from the knowledge that those of ordinary skill in the art possessVarious changes can be made.