JP2022167336A - System and method for high-resolution audio in digital audio processing unit - Google Patents

Abstract

To provide a digital audio processing system and a method for efficiently processing high-resolution audio.SOLUTION: A digital audio processing system 200 executes processing of: dividing a high-resolution audio input signal 202 into an upper sideband signal and a lower sideband signal, applying an advanced audio processing function 208 to the lower sideband signal, simultaneously processing the upper sideband signal in parallel with the lower sideband signal, and applying a high-pass filter 210 to the upper sideband signal; adding volume control 212 to the upper sideband signal to match an audio level of the lower sideband signal; adding delay compensation 214 to the upper sideband signal to match timing of the lower sideband signal; adding phase compensation 216 to the upper sideband signal to match a phase of the lower sideband signal; and mixing 220 the processed upper sideband signal and the processed lower sideband signal to generate high-resolution audio output.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to systems and methods for efficient processing of high resolution audio in digital audio processing units.

Music lovers typically receive music delivered in digital form, such as compressed audio files or compact disc (CD) audio, but music delivered in digital form compares to its analog form or live performances. may degrade the quality of the music. Digital audio formats are based on sampling rate conversion (SRC) used when converting analog music files or live performances to digital format. Audiophiles are music lovers who prefer pure audio and are usually unsatisfied with the quality of compressed audio files or CD audio. High resolution audio is considered to be of superior sound quality and is preferred by audiophiles who expect to hear audio in its purest form. However, high resolution audio requires sampling frequencies that operate well above the typical SRC for compression and compact disc audio formats. A higher SRC for high-resolution audio means significantly more memory and processing power for storing, playing, and streaming audio files compared to the storage and processing power required for compressed and CD audio files. Requires processing power.

Currently, the supply of high resolution audio content is limited. However, this is changing due to the growing demand for high quality audio not only from audiophiles in the consumer goods industry, but also from other industries such as automotive, military and security providers to name a few. As a result of this demand, high resolution audio is becoming increasingly available. However, even when available, its implementation is hampered by the fact that existing audio algorithms do not support higher SRCs for advanced audio processing functions as well as the above file sizes. For existing DSP amplifiers, audio signals above 48 kHz are down-sampled, reducing their sampling rate to make digital audio signals smaller. Unfortunately, this has the effect of removing high resolution content from the audio signal. To overcome this and meet the audiophile demand for pure audio, a possible solution is to implement more memory and processing power to accommodate high resolution audio signals. However, at least double the processing speed (MIPS) is required, adding significant cost and complexity to existing systems.

What is needed is a system and method for processing high resolution audio in an efficient and cost effective digital audio processing unit.

A method and system are for processing high resolution audio in a digital audio processing unit. In one or more embodiments, methods and systems divide a high-resolution audio input signal into upper and lower sideband signals and apply advanced audio processing functions to the lower sideband signals. and simultaneously processing the upper sideband signal in parallel with the lower sideband signal. Simultaneously processing the upper sideband signal includes: applying a high pass filter to the upper sideband signal; adding a volume control to the upper sideband signal to match the audio level of the lower sideband signal; adding delay compensation to the upper sideband signal to match the timing of the lower sideband signal; adding phase compensation to the upper sideband signal to match the phase of the lower sideband signal; Further comprising mixing the processed upper sideband signal and the processed lower sideband signal to produce a high resolution audio output.

In one or more embodiments, methods and systems include playing a high resolution audio output signal on one or more speakers. In one or more embodiments, the methods and systems include applying a highpass filter to the upperband signal. The high pass filter has a cutoff frequency at 24 kHz.
The present invention provides, for example, the following items.
(Item 1)
A method of processing high resolution audio in a digital audio processing unit, comprising:
splitting a high resolution audio input signal into an upper sideband signal and a lower sideband signal;
applying advanced audio processing functions to the lower sideband signal;
concurrently processing said upper sideband signal in parallel with said lower sideband signal, said concurrently processing said upper sideband signal comprising:
applying a high pass filter to the upper sideband signal;
adding a volume control to the upper sideband signal to match the audio level of the lower sideband signal;
adding delay compensation to the upper sideband signal to match the timing of the lower sideband signal;
adding phase compensation to the upper sideband signal to match the phase of the lower sideband signal;
the processing further comprising
mixing the processed upper sideband signal and the processed lower sideband signal to produce a high resolution audio output;
10. The method as executed by a processor having computer-executable instructions for performing the steps of:
(Item 2)
The method of any preceding item, further comprising playing the high resolution audio output signal on one or more speakers.
(Item 3)
A method according to any one of the preceding items, wherein said step of applying said highpass filter to said upperband signal further comprises a filter having a cutoff frequency at 24 kHz.
(Item 4)
A digital audio processing unit that produces a high resolution audio signal to be played on one or more loudspeakers in an audio system having multiple advanced audio processing capabilities, comprising:
The system includes:
a processor;
a splitter for splitting the high resolution audio signal into an upper sideband signal and a lower sideband signal;
a highpass filter applied to the upperband signal;
a mixer;
including
the processor processes the lower sideband signal for the plurality of advanced audio processing functions including volume control, delay compensation, and phase compensation;
simultaneously processing said upper sideband signal in parallel with said lower sideband signal, said upper sideband signal being a volume control matching said volume control, said delay compensation and said phase compensation of said lower sideband signal. , processed only to add delay compensation, and phase compensation,
The digital audio processing unit, wherein the mixer mixes the upper sideband signal and the lower sideband signal after the processing to produce the high resolution audio signal to be played on one or more loudspeakers.
(Item 5)
Any one of the preceding items, wherein the lower sideband signal is downsampled to a 48 kHz signal before the processing and upsampled to 96 kHz after the processing before it is mixed with the upper sideband signal. The system described in .
(summary)
A system and method divides a high-resolution audio input signal into an upper sideband signal and a lower sideband signal, applies advanced audio processing functions to the lower sideband signal, and converts the upper sideband signal to a lower sideband signal. It is for parallel and simultaneous processing with the signal. Simultaneously processing the upper sideband signal includes: applying a high pass filter to the upper sideband signal; adding a volume control to the upper sideband signal to match the audio level of the lower sideband signal; adding delay compensation to the upper sideband signal to match the timing of the lower sideband signal; adding phase compensation to the upper sideband signal to match the phase of the lower sideband signal; Further comprising mixing the processed upper sideband signal and the processed lower sideband signal to produce a high resolution audio output.

1 is a block diagram of a known digital audio processing system with advanced audio processing capabilities; FIG. 1 is a block diagram of a digital audio processing system with advanced audio features and the ability to process high resolution audio simultaneously; FIG. 1 is a flow chart of a system for processing high resolution audio without compromising advanced audio features.

Elements and steps in the figures are illustrated for simplicity and clarity and have not necessarily been presented according to any order. For example, steps that may be performed simultaneously or in a different order are shown in the figures to help improve understanding of the embodiments of the present disclosure.

Although various aspects of the disclosure are described with reference to FIGS. 1-3, the disclosure is not limited to such embodiments and additional modifications, applications, and embodiments may depart from the disclosure. may be implemented without In the figures, like reference numbers are used to denote identical components. Those skilled in the art will recognize that the various components and method steps described herein may be changed without departing from the scope of the disclosure.

FIG. 1 is a block diagram of a known digital audio processing system 100 that supports audio processing up to 48 kHz and how it handles processing of high resolution audio. Digital audio processing system 100 may include one or more digital signal processing (DSP) units that provide audio mixing functions to mix various input and output signals and send them to specific outputs. These outputs may include, but are not limited to, additional signal processors, amplifiers, and loudspeakers. The DSP unit functions to modify effects, physical modeling, and bass management for surround systems that utilize audio processing systems. The DSP unit controls audio equalization (EQ) using gain(s) and filter(s) to provide equalization. Advanced audio processing functions are also accomplished by the DSP unit. For example, surround processing uses operating parameters to provide audio output for a selected audio mode. Audio output streams from one or more DSP units are reproduced on loudspeakers to produce three-dimensional sound. The DSP unit uses multiple parameters to process the sound signal and apply algorithms to extract the audio stream from the music source. Using hardware, software, or both, the DSP unit directs the audio stream to the appropriate speaker positions depending on the listening environment. The DSP unit can also produce stereo, mono, and virtual venue outputs. In another embodiment, the DSP unit may embed spectral and spatial qualities into the audio signal.

In the example shown in FIG. 1, the main audio input 102 is split into two channels at 104 and downsampled from 96 kHz to 48 kHz at 106 for SRC at 48 kHz for advanced audio processing functions. The processed audio is then multiplexed into x-channels, upsampled from 48 kHz back to 96 kHz at 114, and output to respective speakers at 118 (not shown). In addition to advanced features in audio processing systems such as surround sound and virtual venues, it is desirable to include high resolution audio as well. However, as discussed above, SRC at 48 kHz effectively removes high resolution portions of the audio signal when the audio input is downsampled, or requires significantly more memory and processing power. . Both are undesirable consequences of using known systems and methods to process high resolution audio.

FIG. 2 is a block diagram of a digital audio processing system 200 that supports both advanced audio features and high resolution audio signals. The main audio input 202 contains 96 kHz high resolution audio. Again, the main audio input 202 is split between two channels 204 . In the first channel, the signal is downsampled and an SRC up to 48 kHz is applied. In the second channel, the signal passes through a high pass filter 210 that passes only signals above 24 kHz, including high resolution audio.

For the first channel, only signals up to 48 kHz are processed for all audio processing blocks, including advanced audio processing functions, as described in FIG. This allows audio signals to be processed according to advanced audio features such as equalization, tone control, surround sound and virtual venues.

For the second channel, signals above 24 kHz are processed simultaneously and in parallel with the first channel. This signal passes through a high pass filter 210 and undergoes basic audio processing. The signal is subject to volume/mute user control at 212 to ensure that the audio level for high resolution audio matches the 48 kHz audio signal processed on the first channel. A delay compensation 214 is introduced for the second channel to match the timing of the high resolution audio with the 48 kHz audio signal processed on the first channel. Phase compensation 216 is introduced for the second channel to match the phase of the high resolution audio with the 48 kHz audio signal processed on the first channel.

Audio on the first channel is upsampled from 48 kHz to 96 kHz. At 220, the audio from the first channel is mixed with the high resolution audio signal from the second channel. At 222, the completed audio signal is output to associated speakers (not shown) within the audio system.

In one or more embodiments shown in FIG. 2, high resolution audio is distributed over two channels to accommodate two frequency bands. The first band or lower sideband is 0-24 kHz and the second band or upper sideband is for frequencies >24 kHz. The lower sideband signal is downsampled to 48 kHz for advanced audio signal processing such as surround sound. At the same time, the upperband signal undergoes basic signal processing for volume, delay, phase correction and is mixed with a 48 kHz upsampled signal at the output. Appropriate tuning may be applied to ensure that any phase and volume level differences between the lower sideband and upper sideband signals are mitigated at the audio output 222 .

The listener experience is provided by performing complex processing of the lower sideband signal with advanced audio processing capabilities. This is to ensure that only basic processing on the upper sideband signal is performed simultaneously in parallel with the lower sideband signal, keeping MIPS processing low without sacrificing advanced audio processing capabilities. , high resolution can be achieved even with much higher audio. At the output stage, by mixing the upper and lower sidebands, the full high-resolution bandwidth remains intact for output audio without compromising advanced audio processing capabilities on the finished audio signal. is ensured.

FIG. 3 is a flow diagram of one or more methods 300 for processing high resolution audio in a digital audio processing unit. At step 302, a digital audio processing unit receives a main audio input signal containing high resolution audio. At 304, the main audio input is split between the two channels. A first channel is used to process the lower sideband and a second channel is used to process the upper sideband. The upper sideband contains the high resolution components of the audio input signal. At 306, the lower sideband signal is sampled with an SRC up to 48 kHz containing signal content up to 24 kHz.

At step 308, the lower sideband signal undergoes advanced audio signal processing for functions including, but not limited to surround sound, tone control, virtual venues, and the like. At step 310, the upper sideband signal simultaneously undergoes basic audio signal processing to match the volume, delay and phase corrections of the lower sideband signal. This ensures that the upper and lower sideband signals are matched when mixing the signals. At step 312, the lower sideband signal is upsampled from 48 kHz to 96 kHz. At step 314, the upper and lower sideband signals are mixed. Then, at step 316, the audio signals are output to respective speakers (not shown).

In the foregoing specification, the disclosure has been described with reference to specific exemplary embodiments. The specification and drawings are illustrative rather than restrictive, and modifications are intended to be included within the scope of this disclosure. Accordingly, the scope of the present disclosure should be determined by the claims and their legal equivalents, rather than merely by the examples given.

For example, the steps recited in any claimed method or process may be performed in any order and are not limited to the specific order presented in the claims. In addition, the components and/or elements recited in any device claim may be assembled or otherwise configured to be operable in a variety of permutations and thus the patent It is not limited to any particular configuration recited in the claims. Any of the methods or processes described may involve one or more devices such as processors or controllers, memories (including non-transitory ones), sensors, network interfaces, antennas, switches, actuators, etc., to name but a few. It can be done by executing instructions with a device.

While benefits, advantages, and solutions to problems have been described above with respect to the embodiments, any benefit, advantage, solution to a problem, or any particular advantage, advantage or any element that may lead to a solution or make it more apparent should be construed as an important, required, or essential feature or component of any or all claims. does not become

the terms "comprise", "comprises", "comprising", "having", "including", "includes", or Variations of any of them are such that a process, method, article, composition, or apparatus containing a listing of elements not only includes those elements that are listed, but also includes other elements, or other elements specific to such processes, methods, articles, compositions, or devices are intended to refer to non-exclusive inclusion. In addition to those not specifically described, other combinations and/or modifications of the above-described structures, arrangements, uses, proportions, elements, materials, or components used in the practice of the present disclosure may be used in accordance with its general principles. may be varied without departing from or otherwise specifically adapted to particular environments, manufacturing specifications, design parameters, or other operating requirements.

Claims (5)

A method of processing high resolution audio in a digital audio processing unit, comprising:
splitting a high resolution audio input signal into an upper sideband signal and a lower sideband signal;
applying advanced audio processing functions to the lower sideband signal;
concurrently processing said upper sideband signal in parallel with said lower sideband signal, said concurrently processing said upper sideband signal comprising:
applying a high pass filter to the upper sideband signal;
adding a volume control to the upper sideband signal to match the audio level of the lower sideband signal;
adding delay compensation to the upper sideband signal to match the timing of the lower sideband signal;
adding phase compensation to the upper sideband signal to match the phase of the lower sideband signal;
the processing further comprising
mixing the processed upper sideband signal and the processed lower sideband signal to produce a high resolution audio output;
10. The method as executed by a processor having computer-executable instructions for performing the steps of: 2. The method of claim 1, further comprising playing the high resolution audio output signal on one or more speakers. 2. The method of claim 1, wherein said step of applying said highpass filter to said upperband signal further comprises a filter having a cutoff frequency at 24 kHz. A digital audio processing unit that produces a high resolution audio signal to be played on one or more loudspeakers in an audio system having multiple advanced audio processing capabilities, comprising:
The system includes:
a processor;
a splitter for splitting the high resolution audio signal into an upper sideband signal and a lower sideband signal;
a highpass filter applied to the upperband signal;
a mixer;
including
the processor processes the lower sideband signal for the plurality of advanced audio processing functions including volume control, delay compensation, and phase compensation;
simultaneously processing said upper sideband signal in parallel with said lower sideband signal, said upper sideband signal being a volume control matching said volume control, said delay compensation and said phase compensation of said lower sideband signal. , processed only to add delay compensation, and phase compensation,
The digital audio processing unit, wherein the mixer mixes the upper sideband signal and the lower sideband signal after the processing to produce the high resolution audio signal to be played on one or more loudspeakers. 5. The system of claim 4, wherein the lower sideband signal is downsampled to a 48 kHz signal before the processing and upsampled to 96 kHz after the processing before it is mixed with the upper sideband signal. .

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