CN111246034A - Intelligent telephone signal processing method, signal processor and storage medium - Google Patents
Intelligent telephone signal processing method, signal processor and storage medium Download PDFInfo
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- CN111246034A CN111246034A CN202010035003.4A CN202010035003A CN111246034A CN 111246034 A CN111246034 A CN 111246034A CN 202010035003 A CN202010035003 A CN 202010035003A CN 111246034 A CN111246034 A CN 111246034A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M7/00—Arrangements for interconnection between switching centres
- H04M7/006—Networks other than PSTN/ISDN providing telephone service, e.g. Voice over Internet Protocol (VoIP), including next generation networks with a packet-switched transport layer
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M9/00—Arrangements for interconnection not involving centralised switching
- H04M9/08—Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic
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Abstract
The invention discloses an intelligent telephone signal processing method, a signal processor and a storage medium, wherein the intelligent telephone signal processing method comprises the following steps: acquiring an input signal of an intelligent telephone and a far-end signal received by the intelligent telephone; performing linear echo cancellation processing on the input signal to obtain a first signal; and processing the first signal according to the far-end signal, and eliminating the echo signal remained in the first signal. According to the invention, after linear echo cancellation is carried out on the input signal of the intelligent telephone, whether a residual echo signal capable of being detected exists in the signal after the initial echo cancellation is determined again according to the far-end signal, and the residual echo signal is cancelled, so that the echo cancellation in the input signal of the intelligent telephone is complete, and the normal use of the intelligent telephone is ensured.
Description
Technical Field
The present invention relates to the field of intelligent telephone communication, and in particular, to a signal processing method, a signal processor, and a storage medium for an intelligent telephone.
Background
VoIP (voice over Internet protocol) technology can transmit services such as voice, fax, video, and data on an IP network at low cost, so that it is also very common for an intelligent phone based on a VoIP system, and such an intelligent phone generally uses DTMF (dual-tone multi-frequency) signals to work.
Thus, there is still a need for improvement and development of the prior art.
Disclosure of Invention
The present invention provides a method for processing a signal of an intelligent phone, a signal processor, and a storage medium, aiming at solving the problem that an echo signal of the intelligent phone affects the normal operation of the intelligent phone when the intelligent phone is based on VoIP communication in the prior art.
In a first aspect, an embodiment of the present invention provides a method for processing a signal of an intelligent phone, where the method for processing a signal of an intelligent phone includes: acquiring an input signal of an intelligent telephone and a far-end signal received by the intelligent telephone;
performing linear echo cancellation processing on the input signal to obtain a first signal;
and processing the first signal according to the far-end signal, and eliminating the echo signal remained in the first signal.
The method for processing a signal of the smart phone, wherein the performing linear echo cancellation processing on the input signal to obtain a first signal includes:
and performing linear echo cancellation on the input signal according to the far-end signal to acquire the first signal.
The method for processing a signal of a smart phone, where the processing the first signal according to the far-end signal and the eliminating the echo signal remaining in the first signal includes:
and if the first signal comprises a signal consistent with the far-end signal, eliminating the signal consistent with the far-end signal in the first signal.
The method for processing signals of the smart phone, wherein the eliminating the signal consistent with the far-end signal in the first signal comprises:
and replacing the signal which is consistent with the far-end signal in the first signal with silence.
The method for processing a signal of a smart phone, wherein the processing the first signal according to the far-end signal, and after eliminating an echo signal remaining in the first signal, includes:
and sending a signal which is inconsistent with the far-end signal in the first signal to a far end.
The intelligent telephone signal processing method further includes:
and if the first signal does not comprise a signal consistent with the far-end signal, directly sending the first signal to a far end.
The intelligent telephone signal processing method further includes:
and if the far-end signal is not detected, directly sending the first signal to a far end.
In a second aspect, an embodiment of the present invention provides a signal processor, where the signal processor is adapted to call instructions in a storage medium to execute steps of implementing the smartphone signal processing method described in any one of the above.
In a third aspect, an embodiment of the present invention further provides a storage medium, where the storage medium stores one or more programs, and the one or more programs are executable by one or more processors to implement the steps of the smartphone signal processing method described in any one of the above.
The invention has the technical effects that: according to the intelligent telephone signal processing method provided by the invention, after linear echo cancellation is carried out on the input signal of the intelligent telephone, whether a residual echo signal exists in the signal after the initial echo cancellation is determined again according to the far-end signal, and the residual echo signal is cancelled, so that the echo cancellation in the input signal of the intelligent telephone is complete, and the normal use of the intelligent telephone is ensured.
Drawings
Fig. 1 is a flowchart of a first embodiment of a method for processing a signal of a smart phone according to the present invention;
fig. 2 is a schematic block diagram of a first embodiment of a signal processing method for a smart phone according to the present invention;
fig. 3 is a schematic diagram of a smart phone set up to communicate.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer and clearer, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Example one
Referring to fig. 1, fig. 1 is a flowchart illustrating an embodiment of a method for processing a signal of an intelligent phone according to the present invention.
The signal processing method of the intelligent phone is applied to a signal processor, and the signal processor can be arranged in the intelligent phone and can acquire an input signal of the intelligent phone and a received far-end signal. In one embodiment, the method for processing a signal of a smart phone includes the steps of:
s100, acquiring an input signal of the intelligent telephone and a far-end signal received by the intelligent telephone.
As shown in fig. 3, in a process of establishing a call, a connection with a communication platform needs to be established first, specifically, a user dials a number through the intelligent phone, the intelligent phone automatically adds an access code in front of the number dialed by the user, and reports the number to the communication platform through an ONU (Optical Network Unit), after the communication platform establishes an RTP bidirectional connection with the intelligent phone, the communication platform sends a DTMF signal (such as DTMF a, determined according to a protocol between the intelligent phone and the communication platform) in an RTP stream, after the intelligent phone receives the DTMF signal, the signal processor sends a different DTMF signal (such as DTMF B) to the communication platform through the RTP stream, and after the communication platform receives the DTMF signal, the communication platform confirms that the intelligent phone can perform a call, and then performs a subsequent call process. When the intelligent telephone receives the DTMF signal sent by the communication platform and returns another DTMF signal, the DTMF signal sent by the communication platform may generate an echo, so that the communication platform can receive both the DTMF signal that the intelligent telephone needs to return and the DTMF signal sent by the communication platform to the intelligent telephone, which causes a problem in a call flow of the intelligent telephone and a failure in establishing a call. Based on this situation, in a signal processing method of an intelligent phone according to an embodiment, an input signal of the intelligent phone and a far-end signal received by the intelligent phone are acquired, and an echo signal in the input signal is eliminated according to the input signal and the far-end signal.
Specifically, the input signal refers to the signal input to the signal processor, and the far-end signal is a signal sent to the smart phone by a far end (i.e., the communication platform) communicating with the smart phone. The input signal may only include a home signal, that is, a signal that the smart phone needs to transmit to the far end after receiving the far end signal, or may include both the home signal and an echo signal of the far end signal. The echo signal is an echo signal generated by the far-end signal received by the intelligent telephone at the local end of the intelligent telephone. The input signal and the far-end signal may be detected by a DTMF detector.
S200, linear echo cancellation processing is carried out on the input signal, and a first signal is obtained.
Specifically, as described above, the input signal may include both a local end signal and an echo signal, and after the input signal is acquired, the echo signal needs to be cancelled, so that the signal sent by the smart phone to the remote end only includes the signal that the smart phone needs to send to the remote end, and is not interfered by the echo signal.
In this embodiment, the echo cancellation processing is performed twice on the input signal, as shown in fig. 2, linear echo cancellation processing is performed on the input signal to obtain a first signal, and then the residual echo signal in the first signal is removed.
The performing linear echo cancellation processing on the input signal to obtain a first signal includes:
and performing linear echo cancellation on the input signal according to the far-end signal to acquire the first signal.
Specifically, the performing linear echo cancellation on the input signal according to the far-end signal is to obtain a filter coefficient, and perform linear echo cancellation on the input signal according to a mode of an input signal-filter coefficient — far-end signal, which is the prior art and is not described herein again.
However, since the smart phone operates using DTMF signals, the frequency mapping table of DTMF signals is as follows:
it is obvious that many signals, such as DTMF a, B, C, D, have the same high frequency and the same low frequency, but these signals with similar frequency spectrum are easy to be detected and echo cancelled, and the situation that the echo signal remains in the first signal occurs. Therefore, in this embodiment, as shown in fig. 1, the method for processing a signal of a smart phone further includes:
s300, processing the first signal according to the far-end signal, and eliminating the echo signal remained in the first signal.
In this embodiment, after the first signal is obtained, the first signal is further processed according to the far-end signal, so as to ensure that an echo signal remaining in the first signal is eliminated.
Specifically, the processing the first signal according to the far-end signal, and the canceling the echo signal remaining in the first signal includes:
and if the first signal comprises a signal consistent with the far-end signal, eliminating the signal consistent with the far-end signal in the first signal.
Specifically, as described above, the signal that the smartphone needs to send to the remote end is determined according to the signal that the remote end sends to the smartphone, and specifically, after receiving the signal that the remote end sends to the smartphone, the smartphone needs to return a different signal to the remote end, that is, the smartphone needs to send the signal that is different from the remote signal to the remote end according to the remote signal. If the first signal includes a signal consistent with the far-end signal, it is indicated that the far-end signal generates an echo, and the echo canceller does not completely cancel the echo caused by the far-end signal, at this time, a signal consistent with the far-end signal in the first signal is a residual echo signal, and a signal consistent with the far-end signal in the first signal is cancelled. For example, the far-end signal is DTMF a, and the first signal also includes DTMF a, then DTMF a in the first signal is an echo of the far-end signal, and needs to be eliminated.
Specifically, the eliminating the signal in the first signal that is consistent with the far-end signal includes:
and replacing the signal which is consistent with the far-end signal in the first signal with silence.
After processing the first signal and eliminating the echo signal remaining in the first signal, the method for processing a signal of a smart phone further includes:
s400, sending the signal which is inconsistent with the far-end signal in the first signal to a far end.
Specifically, if the first signal includes both a signal consistent with the far-end signal and a signal inconsistent with the far-end signal, after the residual echo signal is eliminated, only the signal inconsistent with the far-end signal is included in the first signal, and the signal inconsistent with the far-end signal is sent to the far-end. For example, the far-end signal is DTMF a, the first signal includes DTMF a and DTMA C, and then DTMF a in the first signal is an echo of the far-end signal, and after the echo is cancelled, DTMF C is sent out.
In one possible implementation manner, the method for processing a signal of a smart phone further includes:
s500, if the first signal does not include a signal consistent with the far-end signal, directly sending the first signal to a far end.
If the first signal does not include a signal identical to the far-end signal, it may be that no echo is generated in the far-end signal, or an echo generated in the far-end signal is completely removed by the echo canceller during initial echo cancellation, and then the first signal may be directly transmitted to a far end.
In another possible implementation manner, the smartphone does not respond to a signal sent from a remote end, but actively sends a signal to the remote end, where the smartphone signal processing method includes:
s600, if the far-end signal is not detected, the first signal is directly sent to a far end.
If the far-end signal is not detected, it is indicated that the smart phone does not respond to a signal sent by the far-end but actively sends a signal to the far-end, then, naturally, no echo caused by the far-end signal exists, that is, the input signal does not include an echo signal, but only includes a signal to be sent to the far-end, and at this time, the first signal is directly sent to the far-end.
It should be understood that, although the steps in the flowcharts of the figures in this specification are shown in order as indicated by the arrows, the steps are not necessarily performed in order as indicated by the arrows. The steps are not performed in the exact order shown and described, and may be performed in other orders, unless explicitly stated otherwise. Moreover, at least a portion of the steps in the flowchart may include multiple sub-steps or multiple stages, which are not necessarily performed at the same time, but may be performed at different times, and the order of performing the sub-steps or stages is not necessarily sequential, but may be performed alternately or alternately with other steps or at least a portion of the sub-steps or stages of other steps.
In summary, the present invention provides a signal processing method for an intelligent phone, an intelligent terminal and a storage medium, where the signal processing method for an intelligent phone determines whether a residual echo signal exists in a signal after initial echo cancellation according to a far-end signal after the initial echo cancellation is performed on an input signal of the intelligent phone, and cancels the residual echo signal, so that echo cancellation in the input signal of the intelligent phone is complete, and normal use of the intelligent phone is ensured.
It will be understood by those skilled in the art that all or part of the processes of the methods of the embodiments described above can be implemented by hardware instructions of a computer program, which can be stored in a non-volatile computer-readable storage medium, and when executed, can include the processes of the embodiments of the methods described above. Any reference to memory, storage, databases, or other media used in embodiments provided herein may include non-volatile and/or volatile memory. Non-volatile memory can include read-only memory (ROM), Programmable ROM (PROM), Electrically Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), or flash memory. Volatile memory can include Random Access Memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDRSDRAM), Enhanced SDRAM (ESDRAM), Synchronous Link DRAM (SLDRAM), Rambus Direct RAM (RDRAM), direct bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).
Example two
Based on the foregoing embodiment, the present invention further provides a signal processor, where the signal processor is adapted to call instructions in a storage medium to implement a method for processing a signal of an intelligent phone, which is specifically described in the first embodiment.
The signal processor, when executing the computer program, may perform at least the following steps:
acquiring an input signal of an intelligent telephone and a far-end signal received by the intelligent telephone;
performing linear echo cancellation processing on the input signal to obtain a first signal;
and processing the first signal according to the far-end signal, and eliminating the echo signal remained in the first signal.
Wherein the performing linear echo cancellation processing on the input signal to obtain a first signal includes:
and performing linear echo cancellation on the input signal according to the far-end signal to acquire the first signal.
Wherein the processing the first signal according to the far-end signal, and the canceling the echo signal remaining in the first signal includes:
and if the first signal comprises a signal consistent with the far-end signal, eliminating the signal consistent with the far-end signal in the first signal.
Wherein the canceling of the signal of the first signal that is coincident with the far-end signal comprises:
and replacing the signal which is consistent with the far-end signal in the first signal with silence.
Wherein the processing the first signal according to the far-end signal, and after eliminating the echo signal remaining in the first signal, comprises:
and sending a signal which is inconsistent with the far-end signal in the first signal to a far end.
And if the first signal does not comprise a signal consistent with the far-end signal, directly sending the first signal to a far end.
And if the far-end signal is not detected, directly sending the first signal to a far end.
EXAMPLE III
A third embodiment of the present invention provides a storage medium storing one or more programs, which are executable by one or more processors to implement the steps of the method for processing a signal of a smart phone according to the first embodiment.
It is to be understood that the invention is not limited to the examples described above, but that modifications and variations may be effected thereto by those of ordinary skill in the art in light of the foregoing description, and that all such modifications and variations are intended to be within the scope of the invention as defined by the appended claims.
Claims (9)
1. A method for processing a signal of a smart phone, the method comprising:
acquiring an input signal of an intelligent telephone and a far-end signal received by the intelligent telephone;
performing linear echo cancellation processing on the input signal to obtain a first signal;
and processing the first signal according to the far-end signal, and eliminating the echo signal remained in the first signal.
2. The method of claim 1, wherein the performing linear echo cancellation processing on the input signal to obtain the first signal comprises:
and performing linear echo cancellation on the input signal according to the far-end signal to acquire the first signal.
3. The method of claim 1, wherein the processing the first signal according to the far-end signal, and wherein the removing the echo signal remaining in the first signal comprises:
and if the first signal comprises a signal consistent with the far-end signal, eliminating the signal consistent with the far-end signal in the first signal.
4. The method of claim 3, wherein said canceling the signal of the first signal that is consistent with the far-end signal comprises:
and replacing the signal which is consistent with the far-end signal in the first signal with silence.
5. The method of claim 1, wherein said processing the first signal based on the far-end signal comprises, after removing an echo signal remaining in the first signal:
and sending a signal which is inconsistent with the far-end signal in the first signal to a far end.
6. The smartphone signal processing method of claim 3, further comprising:
and if the first signal does not comprise a signal consistent with the far-end signal, directly sending the first signal to a far end.
7. The smartphone signal processing method of claim 1, further comprising:
and if the far-end signal is not detected, directly sending the first signal to a far end.
8. A signal processor, characterized in that the signal processor is adapted to call instructions in a storage medium to perform a method for performing a smart phone signal processing according to any of the preceding claims 1-7.
9. A storage medium storing one or more programs, the one or more programs being executable by one or more processors to perform the steps of the smart phone signal processing method of any of claims 1-7.
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