CN103347114A - Bluetooth-based DTMF decoding method and system - Google Patents
Bluetooth-based DTMF decoding method and system Download PDFInfo
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- CN103347114A CN103347114A CN2013102030488A CN201310203048A CN103347114A CN 103347114 A CN103347114 A CN 103347114A CN 2013102030488 A CN2013102030488 A CN 2013102030488A CN 201310203048 A CN201310203048 A CN 201310203048A CN 103347114 A CN103347114 A CN 103347114A
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Abstract
The invention discloses a bluetooth-based dual tone multi frequency (DTMF) decoding method and system. The method comprises the following steps that: a bluetooth module of a vehicle-mounted system carries out communication with an external bluetooth and converts a received voice analog signal into pulse-code modulation (PCM) data; the bluetooth module sends the PCM data to a CPU; a drive program reads the PCM data in the CPU and stores the PCM data to an first-input first-output (FIFO) internal memory; and the PCM data are converted into a corresponding DTMF code. According to the invention, the voice analog signal is converted into the PCM data for transmission by using the bluetooth and the PCM data are converted into the DTMF code, so that the DTMF decoding is realized without an independent decoding chip and thus the cost is lowered. Meanwhile, complicated DTMF decoding can be processed; and the DTMF decoding can be carried out even though there is no sound card and no ADC pin is led out at a car.
Description
Technical field
The present invention relates to DTMF decoding technique field, relate in particular to a kind of DTMF coding/decoding method and system based on bluetooth.
Background technology
DTMF (Dual Tone Multi Frequency) is the dial mode in the telephone, has a wide range of applications in Modern Communication System, has with respect to pulse dialing method that speed is fast, error code is low, the call completing rate advantages of higher.The DTMF principle is to represent digital signal to realize a kind of coding techniques of its function with two specific single audio frequency composite signals.The frequency difference of two single audio frequency, the numeral of representative or the function that realizes are also different.Common 16 buttons wherein have 10 numerical keys 0～9 and 6 function key *, #, A, B, C, D.Owing to according to combinatorial principle, 8 kinds of different single audio signals should be arranged generally.Therefore adoptable frequency also has 8 kinds, namely is referred to as multifrequency.Because its employing is extracted 2 kinds out arbitrarily and is made up to encode from 8 kinds of frequencies, so also be referred to as the coding techniques of " getting 2 in 8 ".
Existing DTMF decoding process generally is that program Solidification is arrived chip, such as single-chip microcomputer, special chip or ARM chip, by hardware dtmf signal is carried out hard decoder.The mode of DTMF decoding can also be decoded with the ADC sampling of ARM, also can utilize sound card recording synchronous decoding, but there is following technical problem, utilize special-purpose chip to carry out hard decoder, increased product cost and manufacturing cost, be difficult for promoting, and do not have sound card at some car machines, when also not drawing the ADC pin, just can't decode.
In view of this, prior art haves much room for improvement and improves.
Summary of the invention
In view of the deficiencies in the prior art, the object of the invention is to provide a kind of DTMF coding/decoding method and system based on bluetooth, the DTMF decoding technique that is intended to solve prior art adopts decoding difficulty, the cost increase that program Solidification is brought to chip, and the problem that can't decode when not having sound card and AC pin.
Technical scheme of the present invention is as follows:
A kind of DTMF coding/decoding method based on bluetooth wherein, may further comprise the steps:
The bluetooth module of S11, onboard system and outside bluetooth communication are converted into the PCM data with the voice analog signal of the outside bluetooth that receives;
S12, described bluetooth module send to CPU with described PCM data;
S13, read the PCM data among the CPU, and it is saved in the FIFO internal memory;
S14, described PCM data are converted into corresponding DTMF sign indicating number.
Described DTMF coding/decoding method based on bluetooth wherein, also comprised before described step S11:
The bluetooth module of S10, onboard system and outside bluetooth are matched, and dialing enters talking state after pairing is finished.
Described DTMF coding/decoding method based on bluetooth wherein, also comprises after described step S14:
Dialing or digital information in S15, the detection DTMF sign indicating number are exported by output equipment.
Described DTMF coding/decoding method based on bluetooth, wherein, described step S14 specifically comprises:
S141, according to the dtmf code table of PCM data query correspondence, draw corresponding DTMF sign indicating number.
A kind of DTMF coding/decoding method based on bluetooth wherein, may further comprise the steps:
S21, the DTMF sign indicating number is converted into corresponding PCM data;
S22, described PCM data are transmitted to the bluetooth module of onboard system by CPU;
S23, described bluetooth module are converted into corresponding voice analog signal with the PCM data that receive;
S24, described voice analog signal is sent to outside bluetooth with the bluetooth module communication.
A kind of DTMF decode system based on bluetooth wherein, comprising:
Bluetooth module, the voice analog signal that is used for receiving with outside bluetooth communication is converted into the PCM data and sends to CPU; Also be used for to be converted into from the PCM data that CPU receives corresponding voice analog signal and send to outside bluetooth with its communication;
CPU is used for the PCM data of bluetooth module are transmitted to software layer; Also be used for the PCM data of software layer are transmitted to bluetooth module;
Software layer, the PCM data for reading CPU are saved to it in FIFO internal memory, more described PCM data are converted into corresponding DTMF sign indicating number; Also be used for the DTMF sign indicating number is converted into corresponding PCM data;
The FIFO internal memory is used for preserving the PCM data.
Described DTMF decode system based on bluetooth, wherein, described software layer comprises:
Driver module is for the PCM data that read CPU;
Modular converter is used for the PCM data are converted into corresponding DTMF sign indicating number, and the DTMF sign indicating number is converted into corresponding PCM data.
Described DTMF decode system based on bluetooth, wherein, described software layer also comprises:
Detection module is for detection of the dialing in the DTMF sign indicating number or digital information.
Described DTMF decode system based on bluetooth wherein, also comprises:
Output equipment is for the detection information of output detection module.
Beneficial effect:
DTMF coding/decoding method and system based on bluetooth of the present invention under Android, Linux, WinCE, Unix or Apple OS operating system, receive the voice analog signal of outside bluetooth by the bluetooth module of onboard system, and are converted into the PCM data; Bluetooth module sends to CPU with described PCM data; Read the PCM data among the CPU again, it is saved in the FIFO internal memory; At last described PCM data are converted into corresponding DTMF sign indicating number; By bluetooth voice analog signal being converted into the PCM data transmits, again the PCM data are converted into the DTMF sign indicating number, thereby realized the DTMF decoding, thereby need not independent decoding chip, reduced cost, can handle simultaneously complicated dtmf code, even do not have sound card on the car machine, also do not draw the ADC pin, also can carry out the DTMF decoding.
Description of drawings
Fig. 1 is the flow chart of DTMF coding/decoding method first embodiment based on bluetooth of the present invention.
Fig. 2 is the corresponding software flow pattern of DTMF coding/decoding method first embodiment based on bluetooth of the present invention.
Fig. 3 is the flow chart of DTMF coding/decoding method second embodiment based on bluetooth of the present invention.
Fig. 4 is the corresponding software flow pattern of DTMF coding/decoding method second embodiment based on bluetooth of the present invention.
Fig. 5 is the schematic diagram of the embodiment of the DTMF decode system based on bluetooth of the present invention.
Embodiment
The invention provides a kind of DTMF coding/decoding method and system based on bluetooth, clearer, clear and definite for making purpose of the present invention, technical scheme and effect, below the present invention is described in more detail.Should be appreciated that specific embodiment described herein only in order to explaining the present invention, and be not used in restriction the present invention.
See also Fig. 1, it is the flow chart of DTMF coding/decoding method first embodiment based on bluetooth of the present invention.As shown in the figure, described DTMF coding/decoding method based on bluetooth wherein, may further comprise the steps:
The bluetooth module of S11, onboard system and outside bluetooth communication are converted into the PCM data with the voice analog signal of the outside bluetooth that receives;
S12, described bluetooth module send to CPU with described PCM data;
S13, read the PCM data among the CPU, and it is saved in the FIFO internal memory;
S14, described PCM data are converted into corresponding DTMF sign indicating number.
Be described in detail at above-mentioned steps respectively below.
Described step S11 is according to user instruction, and bluetooth module and outside bluetooth are carried out communication, is that bluetooth module on the onboard system and outside mobile phone or other bluetooths are carried out communication during practical application, thereby carries out interactive voice.The bluetooth module of onboard system is converted into the PCM data with the voice analog signal that receives again.PCM is the abbreviation of English Pulse-code modulation, and Chinese translation is pulse code modulation.We know in actual life, the sound that people's ear is heard is analog signal, PCM is exactly a kind of technology that will become sound from analog-converted digital signal, its principle briefly is exactly to utilize a fixing frequency to analog signal sampling, the pulse that signal after the sampling differs just as a string continuous amplitude at waveform, the amplitude of these pulses is quantized by certain precision, numerical value after these quantize is exported continuously, is transmitted, is handled or is recorded in the storage medium, and all these have formed the production process of digital audio.The file format of described PCM data is the PCM sign indicating number, and the voice analog signal that bluetooth module will receive with outside bluetooth communication is converted into corresponding PCM sign indicating number, and in step S12, described bluetooth module sends to CPU with the PCM data.
Step S13 is that the driver in the software layer reads the PCM data among the ARM CPU, also the PCM data that read are sent in the FIFO internal memory and preserve, thereby convenient follow-up reading the PCM data and separate is the DTMF sign indicating number.Described FIFO(First Input First Output) saves as first-in first-out memory in.
Step S14 specifically, in software layer, can be converted into the PCM data corresponding DTMF sign indicating number by corresponding algorithm for described PCM data are converted into corresponding DTMF sign indicating number.In this patent, adopt look-up table, according to PCM data query dtmf code table, thereby draw corresponding DTMF sign indicating number, thereby realized the DTMF decoding based on bluetooth.
Further, see also Fig. 2, Fig. 2 is the corresponding software flow pattern of DTMF coding/decoding method first embodiment based on bluetooth of the present invention, as shown in the figure, also comprised before described step S11: the bluetooth module of S10, onboard system and outside bluetooth are matched, and dialing enters talking state after pairing is finished.Specifically, bluetooth module and outside mobile phone or other bluetooth are matched, and after pairing is finished, begin dialing, enter talking state.This is prior art, does not do too much explanation herein.
Further, after described step S14, also comprise: dialing or digital information in S15, the detection DTMF sign indicating number, export by output equipment.Specifically, comprise dialing and voice command information in the described DTMF sign indicating number, the PCM data are converted into after the DTMF sign indicating number, again the DTMF sign indicating number is reduced to initial data, thereby carries out follow-up processing.
When concrete the application, bluetooth module has two to the communication connection of ARM CPU: an order that is based on serial ports transmits, two are based on the voice digital signal of pcm encoder, after the PCM sign indicating number delivered to ARM, the mode that systems such as WinCE, Linux, Unix, Android, Apple OS all can drive is read, be translated into the DTMF sign indicating number, thereby realize the DTMF decoding.DTMF coding/decoding method based on bluetooth provided by the invention need not independent decoding chip, has reduced cost, can handle complicated dtmf code simultaneously, even there is not sound card also not draw the ADC pin on the car machine, also can carry out the DTMF decoding.
Above-mentioned DTMF coding/decoding method first embodiment based on bluetooth is for receiving flow process, and just the voice analog signal of outside bluetooth communication enters the DTMF decoding process of the DTMF decode system based on bluetooth of the present invention.Accordingly, the DTMF coding/decoding method based on bluetooth provided by the invention also comprises transmission flow, just the flow process that the DTMF decoding is sent to outside bluetooth based on the DTMF decode system of bluetooth of the present invention.
Further, see also Fig. 3, Fig. 3 is the flow chart of DTMF coding/decoding method second embodiment based on bluetooth of the present invention.Described first embodiment is for receiving flow process, the transmission flow of corresponding first embodiment of this second embodiment.As shown in Figure 3, described DTMF coding/decoding method based on bluetooth may further comprise the steps:
S21, the DTMF sign indicating number is converted into corresponding PCM data;
S22, described PCM data are transmitted to the bluetooth module of onboard system by CPU;
S23, described bluetooth module are converted into corresponding voice analog signal with the PCM data that receive;
S24, described voice analog signal is sent to outside bluetooth with the bluetooth module communication.
Specifically, the flow chart of described second embodiment is corresponding with the flow chart of first embodiment, in step S21, the DTMF sign indicating number that will comprise dialing or digital information is converted into corresponding PCM data, send to the bluetooth module of onboard system again by ARM CPU, through bluetooth module described PCM data are converted into corresponding voice analog signal and send to outside bluetooth then, thereby realized the transmission that DTMF decodes.See also Fig. 4, Fig. 4 is the corresponding software flow pattern of DTMF coding/decoding method second embodiment based on bluetooth of the present invention.Obviously, in this second embodiment, also comprise the bluetooth module of onboard system and the pairing of outside bluetooth, and dtmf signal is converted into the PCM data, it is corresponding flow process that PCM data among this and first embodiment are converted into the DTMF sign indicating number, and its operation principle no longer repeats too herein.
The present invention also provides a kind of DTMF decode system based on bluetooth, and as shown in Figure 5, described DTMF decode system comprises: bluetooth module 10, CPU20, software layer 30 and FIFO internal memory 40.
Specifically, described bluetooth module 10 is used for being converted into the PCM data and sending to CPU20 with the voice analog signal of outside bluetooth communication reception; Also be used for to be converted into from the PCM data that CPU20 receives corresponding voice analog signal and send to outside bluetooth with its communication.Described CPU20 is used for the PCM data of bluetooth module 10 are transmitted to software layer 30; Also be used for the PCM data of software layer 30 are transmitted to bluetooth module 10.Described software layer 30 is used for reading the PCM data of CPU20, and it is saved in the FIFO internal memory 40, more described PCM data is converted into corresponding DTMF sign indicating number; Also be used for the DTMF sign indicating number is converted into corresponding PCM data.Described FIFO internal memory 40 is used for preserving the PCM data.Described bluetooth module 10 and CPU20 are hardware layer.
Because comprise in the DTMF decoding process receiving flow process and transmission flow, then the processing of the signal in described bluetooth module 10, CPU20, software layer 30 and the FIFO internal memory 40 all is two-way.When practical application, in receiving flow process, described bluetooth module 10 will be converted into the PCM data and send to CPU20 with the voice analog signal that outside bluetooth communication receives, be transmitted to software layer 30 through described CPU20, described software layer 30 is kept at described PCM data in the FIFO internal memory 40, and be translated into corresponding DTMF sign indicating number, thereby realized the DTMF decoding.Described bluetooth module 10 has two with the communication connection of ARM CPU20: the one, for the order transmission of serial ports, the 2nd, for the voice digital signal transmission of pcm encoder, give ARM with the PCM sign indicating number, WinCE, Linux, Unix, Android, the Apple OS mode that all can drive is read like this, and realizes the DTMF decoding.
Specifically, described software layer 30 comprises: driver module, for the PCM data that read CPU; Modular converter is used for the PCM data are converted into corresponding DTMF sign indicating number, and the DTMF sign indicating number is converted into corresponding PCM data.Further, described software layer 30 also comprises: detection module, and for detection of the dialing in the DTMF sign indicating number or digital information.Described detection module detects the dialing in the DTMF sign indicating number or digital information, and exports at output equipment, and described output equipment is loudspeaker etc.
When practical application, in transmission flow, described software layer 30 is converted into corresponding PCM data with the DTMF sign indicating number, send to bluetooth module 10 by CPU20 then, described bluetooth module 10 is converted into corresponding voice analog signal with the PCM data, with outside bluetooth communication, receive in the body thereby send to other, thereby realized the DTMF decoding again.
In sum, DTMF coding/decoding method and system based on bluetooth of the present invention, under Android, Linux, WinCE, Unix or Apple OS operating system, record the voice analog signal that receives outside bluetooth by the bluetooth of onboard system, and be converted into the PCM data; Bluetooth module sends to CPU with described PCM data; Driver reads the PCM data among the CPU, and it is saved in the FIFO internal memory; Described PCM data are converted into corresponding DTMF sign indicating number; Correspondingly, the DTMF sign indicating number in the onboard system is converted into corresponding PCM data; Be transmitted to the bluetooth module of onboard system again by CPU; Described bluetooth module is converted into corresponding voice analog signal with the PCM data that receive; At last described voice analog signal is sent to the outside bluetooth with the bluetooth module communication, thereby realized the DTMF decoding of reception and transmission flow, thereby need not independent decoding chip, reduced cost, can handle simultaneously complicated dtmf code, do not have sound card not draw under the situation of ADC pin at the car machine yet, can carry out the DTMF decoding yet.
Should be understood that application of the present invention is not limited to above-mentioned giving an example, for those of ordinary skills, can be improved according to the above description or conversion that all these improvement and conversion all should belong to the protection range of claims of the present invention.
Claims (9)
1. the DTMF coding/decoding method based on bluetooth is characterized in that, may further comprise the steps:
The bluetooth module of S11, onboard system and outside bluetooth communication are converted into the PCM data with the voice analog signal of the outside bluetooth that receives;
S12, described bluetooth module send to CPU with described PCM data;
S13, read the PCM data among the CPU, and it is saved in the FIFO internal memory;
S14, described PCM data are converted into corresponding DTMF sign indicating number.
2. the DTMF coding/decoding method based on bluetooth according to claim 1 is characterized in that, also comprises before described step S11:
The bluetooth module of S10, onboard system and outside bluetooth are matched, and dialing enters talking state after pairing is finished.
3. the DTMF coding/decoding method based on bluetooth according to claim 1 is characterized in that, also comprises after described step S14:
Dialing or digital information in S15, the detection DTMF sign indicating number are exported by output equipment.
4. the DTMF coding/decoding method based on bluetooth according to claim 1 is characterized in that described step S14 specifically comprises:
S141, according to the dtmf code table of PCM data query correspondence, draw corresponding DTMF sign indicating number.
5. the DTMF coding/decoding method based on bluetooth is characterized in that, may further comprise the steps:
S21, the DTMF sign indicating number is converted into corresponding PCM data;
S22, described PCM data are transmitted to the bluetooth module of onboard system by CPU;
S23, described bluetooth module are converted into corresponding voice analog signal with the PCM data that receive;
S24, described voice analog signal is sent to outside bluetooth with the bluetooth module communication.
6. the DTMF decode system based on bluetooth is characterized in that, comprising:
Bluetooth module, the voice analog signal that is used for receiving with outside bluetooth communication is converted into the PCM data and sends to CPU; Also be used for to be converted into from the PCM data that CPU receives corresponding voice analog signal and send to outside bluetooth with its communication;
CPU is used for the PCM data of bluetooth module are transmitted to software layer; Also be used for the PCM data of software layer are transmitted to bluetooth module;
Software layer, the PCM data for reading CPU are saved to it in FIFO internal memory, more described PCM data are converted into corresponding DTMF sign indicating number; Also be used for the DTMF sign indicating number is converted into corresponding PCM data;
The FIFO internal memory is used for preserving the PCM data.
7. the DTMF decode system based on bluetooth according to claim 6 is characterized in that described software layer comprises:
Driver module is for the PCM data that read CPU;
Modular converter is used for the PCM data are converted into corresponding DTMF sign indicating number, and the DTMF sign indicating number is converted into corresponding PCM data.
8. the DTMF decode system based on bluetooth according to claim 6 is characterized in that described software layer also comprises:
Detection module is for detection of the dialing in the DTMF sign indicating number or digital information.
9. the DTMF decode system based on bluetooth according to claim 8 is characterized in that, also comprises:
Output equipment is for the detection information of output detection module.
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| CN104913788A (en) * | 2014-03-13 | 2015-09-16 | 深圳市赛格导航科技股份有限公司 | Auxiliary navigation method based on call center, system and vehicle navigation terminal |
| CN111313984A (en) * | 2020-02-19 | 2020-06-19 | 北京瑞森新谱科技股份有限公司 | Testing device and method for various audio codes of Bluetooth headset |
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