TWI385647B - Audio data processing device and method - Google Patents

Description

Audio processing device and method

The present invention relates to audio processing, and more particularly to an audio processing apparatus and method.

Lossy compression is widely used for compression of voice, image and video material. Lossy compression exploits the inability of humans to be insensitive to certain frequency components in images or sound waves, allowing for the loss of certain information during compression, in exchange for greater compression ratios.

However, when the digital audio is damaged, the high frequency part will be missing, causing the digital audio to sound very low and the audio quality to be degraded.

In view of this, it is necessary to provide an audio processing device for complementing the missing portion of the high frequency and improving the audio quality.

In addition, an audio processing method is needed to complement the missing portion of the high frequency and improve the audio quality.

The audio processing device in the embodiment of the present invention includes a processor, an S-domain curve storage module, a multiplying S-domain curve storage module, an S-domain curve selection module, a reading module, a multiplying S-domain curve selection module, and an insertion. Point module and output module. The S-domain curve storage module is used to store various S-domain curves, which respectively correspond to the utilization rates under different operating conditions of the processor. The multiplying S-domain curve storage module is used to store various multiplying S-domain curves. The S-domain curve selection module is configured to select an appropriate S-domain curve from the S-domain curve storage module according to the current utilization rate of the processor. The reading module is used for reading audio data, and the audio data includes sampling frequency and original points. The multiplying S-domain curve selection module is configured to select the multiplying S-domain curve from the multiplying S-domain curve storage module according to the selected S-domain curve and the sampling frequency. The interpolation module is used to interpolate the original points according to the selected magnification S-domain curve. The output module is used to output the audio data after the interpolation operation.

The audio processing method in the embodiment of the present invention includes the following steps: Provide various S-domain curves, respectively corresponding to the utilization of the processor under different working conditions; provide various multi-rate S-domain curves; read fixed-length audio data, including sampling frequency and original points; determine processor utilization, And selecting the corresponding S-domain curve according to the utilization rate; selecting the multiplicative S-domain curve according to the selected S-domain curve and the sampling frequency; and interpolating the original points of the audio data according to the selected magnification S-domain curve; outputting the interpolation point The audio data after the operation.

The above and the technical effects of the invention can be easily understood from the following detailed description of the embodiments and the accompanying drawings.

Please refer to FIG. 1, which is a block diagram of an audio processing device 10 according to an embodiment of the present invention. In the present embodiment, the audio processing device 10 is configured to perform an interpolation operation on the audio data to improve the sound quality.

In the present embodiment, the audio processing device 10 includes a processor 101, an S-domain curve storage module 102, an S-domain curve selection module 103, a reading module 104, a multiplying S-domain curve storage module 105, and a magnification S-domain curve. The module 106, the multiplying S-domain curve generating module 107, the interpolating module 108, the output module 109, and the judging module 110 are selected.

The processor 101 is configured to perform various tasks of the audio processing device 10, including executing the modules 102-110 described above.

The S-domain curve storage module 102 is used to store various S-domain curves. In the present embodiment, the S-domain curve is formed by dividing the number of different points according to the percentage of frequency variation, including 64-point, 32-point, 16-point, 8-point, 4-point S-domain curves, and the like. 2(a) is an example diagram of a 4-point S-domain curve, and FIG. 2(b) is an example diagram of a 64-point S-domain curve, wherein the abscissa is a point number, The ordinate is the percentage change in frequency between points. As can be seen from Figures 2(a) and (b), the more points, the clearer the frequency change. In the present embodiment, the S-domain curves of various points correspond to the utilization suitability of the processor 101 under different operating conditions. For example, the 64-point S-domain curve corresponds to the processor 101 utilization rate in the 1-20% interval, and the 4-point S-domain curve pair The utilization rate of the processor 101 should be in the range of 80-100%. In this way, the processor 101 can be reasonably utilized to improve the efficiency of audio processing.

The S-domain curve selection module 103 selects a corresponding S-domain curve from the S-domain curve storage module 102 according to the current utilization rate of the processor 101. The corresponding rule may be preset. For example, when the processor 101 utilization rate is in the interval of 1-20%, the 64-point S-domain curve is selected, or when the processor utilization is in the interval of 80-100%, 4 points are selected. S domain curve.

The reading module 104 is configured to read a fixed length of audio data. In this embodiment, the audio data includes a sampling frequency and an original number of points.

The sampling frequency is the number of samples per second. The higher the sampling frequency, the higher the frequency of the sound wave that can be described, and the more realistic and natural the restored sound is. The sampling frequency generally includes 11.025KHz, 22.05KHz, 44.1KHz, etc., wherein 44.1KHz is the theoretical CD sound quality limit. Referring to the audio data example diagram of FIG. 3, as shown in FIG. 3(a), it is a piece of audio data with a sampling frequency of 11.025 kHz. As shown in FIG. 3(b), for the fixed length audio data read by the reading module 104, in the present embodiment, the sampling frequency of the audio data is 11.025 KHz, and the original number of points at a fixed length is 4 points. .

The multiplying S-domain curve storage module 105 stores various multiplying S-domain curves. Referring to FIG. 4, an exemplary diagram of a 4-point magnification S-domain curve in the present embodiment is shown.

The multiplying S-domain curve selection module 106 determines whether there is a multiplying S-domain curve corresponding to the current sampling frequency and the current S-domain curve in the multiplicative S-domain curve storage module 105.

The multiplying S-domain curve generating module 107 is configured to generate a corresponding multiplying S-domain curve when the multiplying S-domain curve selecting module 106 determines that there is no corresponding multiplying S-domain curve. In the present embodiment, the magnification S-domain curve generation module 107 performs a magnification expansion point number on the S-domain curve according to the ratio of the standard sampling frequency to the current sampling frequency to generate a corresponding magnification S-domain curve. For example, the audio data of Figure 3(b) has a sampling frequency of 11.025 kHz. For the preset standard sampling frequency of 44.1KHz, it is necessary to expand into 4 identical points in the original length range for each point in Fig. 2(a), and generate a 4-point multiplication S-domain curve as shown in Fig. 4. Example diagram.

The puncturing module 108 interpolates the original points of the audio data read by the reading module 104 according to the multiplying S-domain curve. In the present embodiment, the audio data of the audio data of FIG. 3(b) is subjected to the interpolation operation according to the 4-point magnification S-domain curve of FIG. 4, and FIG. 3(c) is referred to. In the present embodiment, the interpolation module 108 performs a linear interpolation operation on the original number of points according to the selected magnification S-domain curve. In the present invention, the audio processing device 10 adds the high frequency signal to the original audio data by the interpolation operation of the interpolation module 108, thereby improving the sound quality of the low rate audio.

As shown in Fig. 3(c), the number of points inserted between i and i+1 is 16-1 = 15 points in Fig. 4.

The frequency of each point inserted is (the frequency of the i+1 point - the frequency of the i point) * the percentage of the corresponding j point of the rate S domain curve.

The output module 109 outputs the audio data after the interpolation operation of the interpolation module 108 for subsequent decoding.

The determining module 110 is configured to determine whether there is still audio information to be processed, and when there is audio information to be processed, the reading module 104 is notified to continue reading the audio data.

In the present invention, the audio processing device 10 adds a high frequency signal to the original frequency spectrum by interpolation, thereby improving the sound quality of the low bit rate audio.

Referring to FIG. 5, a flow chart of an embodiment of an audio processing method according to the present invention is shown. In the present embodiment, the audio processing method is implemented by the audio processing device 10 shown in FIG.

In step S201, the S-domain curve storage module 102 provides various S-domain curves, which respectively correspond to the utilization rates of the processor 101 under different operating conditions. In the present embodiment, the S-domain curve is formed by dividing the number of different points according to the percentage change of the frequency, and the S-domain curve of different points corresponds to the utilization rate of the processor 101 under different working conditions.

In step S202, the multiplying S-domain curve storage module 105 provides various multiplying S-domain curves.

In step S203, the reading module 104 reads a fixed length of audio material. In this embodiment, the audio data includes a sampling frequency and an original number of points. Referring to the audio data example diagram of FIG. 3(b), in the present embodiment, the sampling frequency of the audio data is 11.025 KHz, and the original number of points at a fixed length is 4 points.

In step S204, the S-domain curve selection module 103 determines the utilization rate of the processor 101, and selects the S-domain curve in the S-domain curve storage module 102 according to the utilization rate of the processor 101. In the present embodiment, different S-domain curves can be flexibly selected. When the utilization rate of the processor 101 is high, a lower number of points is selected, which can avoid a greater burden on the processor 101. When the utilization rate of the processor 101 is low, a higher number of points can be used, which can be reasonably utilized. The resources of the processor 101. For example, if the utilization rate of the processor 101 is 87%, a 4-point S-domain curve is selected, see Figure 2(a).

In step S205, the magnification S-domain curve selection module 106 reads the sampling frequency of the audio material. The sampling frequency as shown in Fig. 3(a) is 11.025 kHz.

In step S206, the magnification S-domain curve selection module 106 determines whether there is a magnification S-domain curve corresponding to the current sampling frequency and the current S-domain curve in the magnification S-domain curve storage module 105.

If not, step S207 is executed, and the multiplying S-domain curve generating module 107 generates a multiplying S-domain curve corresponding to the current sampling frequency and the current S-domain curve. For example, the audio data of Figure 3(b) has a sampling frequency of 11.025 kHz. If the interpolation point is a preset standard sampling frequency of 44.1 kHz, it needs to be expanded to 4 in the original length range for each point in Figure 2(a). The same point, an example diagram of the 4-point multiplication S-domain curve of Fig. 4 is generated.

If the multiplicative S-domain curve exists or has been generated, step S208 is executed, and the interpolation module 108 performs the interpolation operation on the original point number of the audio data in the reading module 104 according to the magnification S-domain curve. Referring to FIG. 3(c), the interpolation module 108 performs linear interpolation on the original points according to the magnification S-domain curve. Count. In the present invention, the audio processing device 10 adds a high frequency signal to the original audio data by interpolation to improve the sound quality of the low bit rate audio.

As shown in Fig. 3(c), the number of points inserted between i and i+1 is 16-1 = 15 points in Fig. 4. The frequency of each point inserted is (the frequency of the i+1 point - the frequency of the i point) * the percentage of the corresponding j point of the rate S domain curve.

In step S209, the output module 109 outputs the audio data after the interpolation operation to perform subsequent decoding processing.

In step S210, the determination module 110 determines whether there is still audio information to be processed. If yes, the process returns to step S203 to notify the reading module 104 to continue reading. If not, it ends.

Referring to FIG. 6, there is shown a comparison of the effects of the audio data processed by the audio processing in FIG. 3(b) and the audio data processed by the audio processing in FIG. 3(c). Fig. 6(a) and Fig. 6(b) show the decibel map of the audio data without audio processing and audio processing, respectively, and it can be seen that the size of the sound does not change significantly. Figure 6(c) is a frequency diagram of audio data without audio processing, analyzed by short time fourier transform (STFT), whose frequency is distributed between 0-5KHz, and the sound is very low, Figure 6 ( d) is the frequency map of the audio data after audio processing, the frequency is distributed between 0-15KHz, the high frequency above 5KHz is complemented, the sound is more real and natural.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. The above description is only the preferred embodiment of the present invention, and equivalent modifications or variations made by those skilled in the art will be included in the following claims.

10‧‧‧Operation processing device

101‧‧‧ processor

102‧‧‧S domain curve storage module

103‧‧‧S domain curve selection module

104‧‧‧Reading module

105‧‧‧Rated S-domain curve storage module

106‧‧‧Rated S-domain curve selection module

107‧‧‧Rated S-domain curve generation module

108‧‧‧Plug module

109‧‧‧Output module

110‧‧‧Judgement module

1 is a block diagram of an audio processing device according to an embodiment of the present invention.

2 is a diagram showing an example of an S-domain curve in an embodiment of the present invention.

FIG. 3 is a diagram showing an example of audio data in an embodiment of the present invention.

4 is a diagram showing an example of a magnification S-domain curve in an embodiment of the present invention.

FIG. 5 is a flowchart of an audio processing method according to an embodiment of the present invention.

6 is an unprocessed audio data and processing in an embodiment of the present invention; A comparison of the effects of the subsequent audio data.

10‧‧‧Operation processing device

101‧‧‧ processor

102‧‧‧S domain curve storage module

103‧‧‧S domain curve selection module

104‧‧‧Reading module

105‧‧‧Rated S-domain curve storage module

106‧‧‧Rated S-domain curve selection module

107‧‧‧Rated S-domain curve generation module

108‧‧‧Plug module

109‧‧‧Output module

110‧‧‧Judgement module

Claims (12)

An audio processing device having a processor, the audio processing device comprising: an S-domain curve storage module for storing various S-domain curves, the S-domain curves respectively corresponding to utilization rates of the processor under different working conditions; The S-domain curve storage module is configured to store various multi-rate S-domain curves; the S-domain curve selection module is configured to select an appropriate S-domain curve from the S-domain curve storage module according to the current utilization rate of the processor; a module for reading audio data, the audio data comprising a sampling frequency and an original point; a magnification S-domain curve selection module, configured to store a mode from the multiplicative S-domain curve according to the selected S-domain curve and the sampling frequency The multiplier S-domain curve is selected in the group; the interpolation module is used for interpolating the original point according to the selected multiplying S-domain curve; and the output module is configured to output the audio data after the interpolation operation. The audio processing device of claim 1, wherein the S-domain curve is arranged by a percentage of different points according to a frequency change. The audio processing device of claim 2, wherein the utilization rate of the processor under different operating conditions corresponds to an S-domain curve of different points. The audio processing device according to claim 1, further comprising a multiplying S-domain curve generating module, configured to use the multiplying S-domain curve selecting module When the corresponding multiplicative S-domain curve is not selected from the multiplying S-domain curve storage module, a corresponding multiplying S-domain curve is generated and provided to the multiplicative S-domain curve storage module for storage. The audio processing device of claim 4, wherein the multiplying S-domain curve generating module generates the multiplicative S-domain curve according to the selected S-domain curve and the sampling frequency. The audio processing device of claim 1, further comprising a determining module, configured to determine whether there is still audio information to be processed, and when present, notify the reading module to continue reading the audio data. The audio processing device according to claim 1, wherein the interpolation module performs a linear interpolation operation on the original point number according to the magnification S-domain curve. An audio processing method is applied to an audio processing device having a processor, the audio processing method comprising: providing various S-domain curves, respectively corresponding to utilization rates of the processor under different working conditions; providing various multi-rate S-domain curves; Taking a fixed length of audio data, the audio data includes a sampling frequency and a number of original points; determining the utilization rate of the processor, and selecting a corresponding S-domain curve according to the utilization; selecting according to the selected S-domain curve and the sampling frequency Magnification S domain curve; Interpolating the original number of points according to the selected multiplying S-domain curve; and outputting the audio data after the interpolation operation. The audio processing method of claim 8, wherein the step of selecting a multiplying S-domain curve according to the selected S-domain curve and the sampling frequency comprises: determining whether there is a corresponding multiplying S-domain curve; if present, Select the corresponding magnification S-domain curve; or if not, generate a corresponding magnification S-domain curve and store it. The audio processing method according to claim 8, wherein the interpolation operation is a linear interpolation of the original points according to the multiplication S-domain curve. The audio processing method of claim 8, further comprising: determining whether there is still audio information to be processed; if yes, continuing to read the audio data; or if not, ending the audio processing. The audio processing method according to claim 8, wherein the S-domain curve is arranged by a percentage of different points according to a frequency change.