CN112672253A - PCM data modulation method and device - Google Patents
PCM data modulation method and device Download PDFInfo
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- CN112672253A CN112672253A CN202011449339.1A CN202011449339A CN112672253A CN 112672253 A CN112672253 A CN 112672253A CN 202011449339 A CN202011449339 A CN 202011449339A CN 112672253 A CN112672253 A CN 112672253A
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Abstract
A PCM data modulation method and device, wherein the method includes the following steps, carry on the interpolation resampling to the PCM data under the mode of oversampling rate, carry on Delta-Sigma modulation to the audio frequency after interpolation resampling, arrange the 1-bit dataflow after Delta-Sigma modulation according to the high order first, fill to the bit position in I2S/PCM data register and export sequentially. Through the scheme, the 1-bit data stream is filled and output according to the I2S data format by converting PCM data into a Delta-Sigma modulation algorithm; the resampling interpolation to Delta Sigma modulation output meets the operating slot requirements for each audio frame. The I2S/PCM interface can realize the output of 1bit data bit, does not need to be externally hung with a more expensive and complicated audio Codec chip, saves the cost and has better practicability.
Description
Technical Field
The invention relates to the field of audio modulation, in particular to a modulation processing method for improving PCM data compatibility.
Background
At present, the mainstream embedded consumer products are more and more based on the Linux operating system, and the carried main control chip usually does not have the integrated audio Codec IP function, and only provides an I2S/PCM digital audio interface to be connected to an external Codec audio chip for working. Some products which are not high in audio playing tone quality requirement but sensitive to cost are externally connected with a Codec chip, so that extra material cost is brought, the PCB wiring is increased, and the difficulty of debugging the Codec chip is increased. Like the prior art: the disclosed document is a document of https:// my. oschira. net/u/4277049/blog/3638113, and the document is used for realizing oversampling on an interface of I2S on an RTOS system, and needs to forcedly improve the DATA rate and the sampling rate of hardware output, so that the requirement on the clock accuracy of a chip is higher. Another prior art, such as CN201310636558, is a solution for implementing a method and apparatus for implementing a digital speaker system based on multi-bit delta-sigma modulation, which is not utilized on linux platform and only can perform multi-bit output.
Disclosure of Invention
Therefore, a new PCM data modulation method needs to be provided, which can achieve the purpose of reducing and improving the compatibility of PCM data under the LINUX platform;
in order to achieve the above object, the inventor provides a PCM data modulation method, which includes the following steps of performing interpolation resampling on PCM data in an oversampling rate mode, performing Delta Sigma modulation on audio subjected to interpolation resampling, arranging a 1-bit data stream subjected to Delta Sigma modulation in a high-order-first mode, and sequentially filling the data stream into a bit output in an I2S/PCM data register.
Specifically, the method further comprises the steps of establishing an ALSA plug-in unit in the linux user layer, and performing interpolation resampling and Delta-Sigma modulation through the ALSA plug-in unit.
Specifically, the I2S/PCM data is in stereo format, and the PCM data bit width is 32bit or 64 bit.
A PCM data modulation device comprises a resampling module, a modulation module and a register module, wherein the resampling module is used for carrying out interpolation resampling on PCM data in an oversampling rate mode, the modulation module is used for carrying out Delta-Sigma modulation on audio after interpolation resampling, and the register module is used for arranging a 1-bit data stream after Delta-Sigma modulation according to a high-order-first mode and sequentially filling the data stream into a bit position in a data register of I2S/PCM for output.
Specifically, the system further comprises a plug-in establishing module, wherein the plug-in establishing module is used for establishing an ALSA plug-in a linux user layer, and interpolation resampling and Delta-Sigma modulation are carried out through the ALSA plug-in.
Specifically, the I2S/PCM data is in stereo format, and the PCM data bit width is 32bit or 64 bit.
Optionally, an I2S/PCM audio interface is further included, the I2S/PCM audio interface being for receiving output data of the register module.
Through the scheme, the 1-bit data stream is filled and output according to the I2S data format by converting PCM data into a Delta-Sigma modulation algorithm; the resampling interpolation to Delta Sigma modulation output meets the operating slot requirements for each audio frame. The I2S/PCM interface can realize the output of 1bit data bit, does not need to be externally hung with a more expensive and complicated audio Codec chip, saves the cost and has better practicability.
Drawings
Fig. 1 is a flowchart of a PCM data modulation method according to an embodiment of the present invention;
fig. 2 is a block diagram of a PCM data modulation apparatus according to an embodiment of the present invention.
Detailed Description
To explain technical contents, structural features, and objects and effects of the technical solutions in detail, the following detailed description is given with reference to the accompanying drawings in conjunction with the embodiments.
Referring to fig. 1, a PCM data modulation method includes a step S101 of performing interpolation resampling on PCM data in an oversampling rate mode, and operating in a higher oversampling rate mode, so that the requirement for an analog anti-aliasing filter can be more easily achieved. S102, the audio after interpolation resampling is subjected to Delta-Sigma modulation, after the Delta-Sigma modulation, noise is shaped, and the noise of a low-frequency part is pushed to a high-frequency part more intensively, so that the method has a better fidelity effect. S103, arranging the 1-bit data stream modulated by Delta-Sigma in a high-order-first mode, and sequentially filling the data stream into a bit position in a data register of I2S/PCM for output. Specifically, the I2S/PCM data is in stereo format, and the PCM data bit width is 32bit or 64 bit. In this way, 32 or 64 times oversampled output may be equivalently achieved, and the I2S/PCM drive clock may remain unchanged. In some further embodiments, the I2S/PCM data is output through an I2S/PCM audio interface, and after passing through an analog low-pass filter and an analog power amplifier, the sound can be played on a loudspeaker. After passing through the analog low-pass filter, quantization noise in most low frequency bands can be eliminated, and therefore the overall signal-to-noise ratio is improved. The scheme has the technical effects of low cost and compatibility with the chip of the Linux kernel.
In some other specific embodiments, the method further includes the step of establishing an ALSA plug-in (abbreviation of Advanced Linux Sound Architecture plug-in) on the Linux user layer, which provides support for audio and MIDI (Musical Instrument Digital Interface) on the Linux operating system, and in this embodiment, we can perform interpolation resampling and Delta-Sigma modulation through the ALSA plug-in, so that the method can be better applied to a hardware chip of the Linux kernel.
In the embodiment shown in fig. 2, a PCM data modulation apparatus is shown, which includes a resampling module 200, a modulation module 201, and a register module 202, where the resampling module is configured to perform interpolation resampling on PCM data in an oversampling rate mode, the modulation module is configured to perform Delta-Sigma modulation on interpolated and resampled audio, and the register module is configured to arrange a 1-bit data stream, which is subjected to Delta-Sigma modulation, in a high-order-first manner, and sequentially fill bit outputs into a data register of I2S/PCM.
Specifically, the system further comprises a plug-in establishing module 203, wherein the plug-in establishing module is used for establishing an ALSA plug-in the linux user layer, and performing interpolation resampling and Delta-Sigma modulation through the ALSA plug-in.
Specifically, the I2S/PCM data is in stereo format, and the PCM data bit width is 32bit or 64 bit.
Optionally, an I2S/PCM audio interface is further included, the I2S/PCM audio interface being for receiving output data of the register module.
It should be noted that, although the above embodiments have been described herein, the invention is not limited thereto. Therefore, based on the innovative concepts of the present invention, the technical solutions of the present invention can be directly or indirectly applied to other related technical fields by making changes and modifications to the embodiments described herein, or by using equivalent structures or equivalent processes performed in the content of the present specification and the attached drawings, which are included in the scope of the present invention.
Claims (7)
1. A PCM data modulation method is characterized by comprising the following steps of carrying out interpolation resampling on PCM data in an oversampling rate mode, carrying out Delta-Sigma modulation on audio subjected to interpolation resampling, arranging a 1-bit data stream subjected to Delta-Sigma modulation according to a high-order-first mode, and sequentially filling bit positions in a data register of I2S/PCM to output.
2. The PCM data modulation method according to claim 1, further comprising the step of establishing an ALSA plug-in at the linux user layer, and performing interpolation resampling and Delta-Sigma modulation through the ALSA plug-in.
3. A PCM data modulation method according to claim 1 wherein I2S/PCM data is in stereo format standard, the PCM data bit width being 32bit or 64 bit.
4. The device for modulating the PCM data is characterized by comprising a resampling module, a modulation module and a register module, wherein the resampling module is used for carrying out interpolation resampling on the PCM data in an oversampling rate mode, the modulation module is used for carrying out Delta-Sigma modulation on audio subjected to interpolation resampling, and the register module is used for arranging a 1-bit data stream subjected to Delta-Sigma modulation according to a high-order-priority mode and sequentially filling the data stream into a bit position in an I2S/PCM data register for outputting.
5. The PCM data modulation device according to claim 4, further comprising a plug-in establishing module, wherein the plug-in establishing module is used for establishing an ALSA plug-in the linux user layer, and performing interpolation resampling and Delta-Sigma modulation through the ALSA plug-in.
6. A PCM data modulation according to claim 4, wherein I2S/PCM data is in stereo format, PCM data bit width is 32bit or 64 bit.
7. A PCM data modulation according to claim 4 and further comprising an I2S/PCM audio interface, said I2S/PCM audio interface being adapted to receive the output data of the register block.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114697401A (en) * | 2022-03-14 | 2022-07-01 | 广州广哈通信股份有限公司 | Audio data transmission method |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6405092B1 (en) * | 1997-09-29 | 2002-06-11 | William Vincent Oxford | Method and apparatus for amplifying and attenuating digital audio |
| CN101640055A (en) * | 2008-07-30 | 2010-02-03 | 索尼株式会社 | Signal processing device, signal processing method, and signal level display device |
| CN103107813A (en) * | 2012-11-13 | 2013-05-15 | 长沙景嘉微电子股份有限公司 | Voice frequency digital-to-analog converter (DAC) circuit with Class-AB output |
| CN103944575A (en) * | 2014-04-21 | 2014-07-23 | 中国科学院半导体研究所 | Oversampling 64-time sigma-delta modulation circuit with effective bit being 18 |
| CN105208021A (en) * | 2015-09-14 | 2015-12-30 | 英特格灵芯片(天津)有限公司 | Data communication method and system |
| KR101619879B1 (en) * | 2014-12-22 | 2016-05-11 | 주식회사 아이리버 | Apparatus for playing dsd audio file using programmable device and method thereof |
| US20160309274A1 (en) * | 2013-12-02 | 2016-10-20 | Suzhou Sonavox Electronics Co., Ltd. | Implementation method and device of multi-bit modulation-based digital speaker system |
| CN107205206A (en) * | 2016-03-17 | 2017-09-26 | 北京卓锐微技术有限公司 | Microphone test device, system and method for testing |
| CN206962798U (en) * | 2017-06-20 | 2018-02-02 | 上海工程技术大学 | A kind of over-sampling △ ∑ digital analog converters |
| CN111901115A (en) * | 2020-07-27 | 2020-11-06 | 合肥工业大学 | SIMON algorithm encryption circuit in multi-configuration mode |
-
2020
- 2020-12-09 CN CN202011449339.1A patent/CN112672253B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6405092B1 (en) * | 1997-09-29 | 2002-06-11 | William Vincent Oxford | Method and apparatus for amplifying and attenuating digital audio |
| CN101640055A (en) * | 2008-07-30 | 2010-02-03 | 索尼株式会社 | Signal processing device, signal processing method, and signal level display device |
| CN103107813A (en) * | 2012-11-13 | 2013-05-15 | 长沙景嘉微电子股份有限公司 | Voice frequency digital-to-analog converter (DAC) circuit with Class-AB output |
| US20160309274A1 (en) * | 2013-12-02 | 2016-10-20 | Suzhou Sonavox Electronics Co., Ltd. | Implementation method and device of multi-bit modulation-based digital speaker system |
| CN103944575A (en) * | 2014-04-21 | 2014-07-23 | 中国科学院半导体研究所 | Oversampling 64-time sigma-delta modulation circuit with effective bit being 18 |
| KR101619879B1 (en) * | 2014-12-22 | 2016-05-11 | 주식회사 아이리버 | Apparatus for playing dsd audio file using programmable device and method thereof |
| CN105208021A (en) * | 2015-09-14 | 2015-12-30 | 英特格灵芯片(天津)有限公司 | Data communication method and system |
| CN107205206A (en) * | 2016-03-17 | 2017-09-26 | 北京卓锐微技术有限公司 | Microphone test device, system and method for testing |
| CN206962798U (en) * | 2017-06-20 | 2018-02-02 | 上海工程技术大学 | A kind of over-sampling △ ∑ digital analog converters |
| CN111901115A (en) * | 2020-07-27 | 2020-11-06 | 合肥工业大学 | SIMON algorithm encryption circuit in multi-configuration mode |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114697401A (en) * | 2022-03-14 | 2022-07-01 | 广州广哈通信股份有限公司 | Audio data transmission method |
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