Design method of visual piano key rhythm lamp

Abstract

The invention discloses a design method of a visual piano key rhythm lamp, which comprises the following steps of: performing mask processing on high and low frequency bands at two poles of music audio to complete frequency screening; identifying the center frequency of the music, and increasing the weight ratio of a center frequency band by using a band-pass filter; carrying out nonlinear change on the frequency according to the Mel scale on the basis of the characteristics of a human ear sensory sensitive area; and according to the obtained frequency information, setting the time duration of gradually lightening and gradually extinguishing the LEDs, and executing the action of gradually lightening and gradually extinguishing the piano key type LEDs. According to the method, the frequency characteristics of the music audio are deeply analyzed and processed, so that the interactive experience between the audio and the vision can be effectively improved; and according to the processed frequency information, the gradually-on and gradually-off time of the LED is configured, and the piano-key-type visual feedback action is executed, so that the expressive force of the audio is improved, the immersion and participation sense of the user are enhanced through the visual effect, and a brand new dimension is brought to the experience of passengers.

Description

Technical Field

[0001] The present invention belongs to the technical field of automotive lighting, and particularly relates to a design method for a visual piano key rhythm lamp. Background Art

[0002] With the development of the automotive industry and the increasing demand for personalization among consumers, the lighting effects of traditional unlocking and locking vehicle lights and fixed lighting methods can no longer meet people's requirements for aesthetics and interest. Some music rhythm atmosphere lights are gradually equipped on some high-end vehicles. The characteristics of this kind of music rhythm light are customizable, personalized, and diverse, which can meet the usage needs of many high-end users.

[0003] However, the traditional piano key rhythm lamp is based on the instantaneous frequency obtained from music sampling, and a fixed mapping relationship between the lamp beads and the frequency is formulated through software. When the music plays, the LEDs corresponding to the frequency are directly lit, resulting in a rigid rhythm effect for some music and presenting an uncoordinated visual and auditory feeling to users.

[0004] Therefore, there is an urgent need for a design method for a visual piano key rhythm lamp, in which the frequency intervals extracted from each piece of music will be diverse and personalized, and the frequency is more in line with the sensitivity of the human ear. At the same time, the gradually brightening and dimming effect of the lamp beads is updated adaptively to achieve rich rhythm and layering as the music progresses. Summary of the Invention

[0005] The purpose of the present invention is to provide a design method for a visual piano key rhythm lamp to solve the problems raised in the above background art. A design method for a visual piano key rhythm lamp provided by the present invention has the characteristics of adaptively updating the gradually brightening and dimming effect of the lamp beads to achieve rich rhythm and layering as the music progresses.

[0006] To achieve the above purpose, the present invention provides the following technical solutions: A design method for a visual piano key rhythm lamp, including the following steps:

[0007] S1. Mask the two poles of the high and low frequency bands of the music audio to complete frequency screening;

[0008] S2. Identify the center frequency of the music and use a band-pass filter to increase the weight ratio of the center frequency band;

[0009] S3. Based on the characteristics of the human ear's sensitive area, perform non-linear transformation on the frequency according to the Mel scale;

[0010] S4. According to the obtained frequency information, set the time length for the LED to gradually brighten and dim, and perform the action of the piano key-style LED to gradually brighten and dim.

[0011] In the present invention, further, in step S1, the method for audio frequency screening and processing is as follows: receive the in-vehicle music signal through an audio transceiver, read the audio information, sample the music, use the fast Fourier transform to convert the music from a time-domain signal to a frequency-domain signal, set a masking function, set the masking value within the selected frequency range to 1, and set the masking value outside the range to 0.

[0012] In the present invention, further, the selected frequency range is 27HZ - 4186HZ.

[0013] In the present invention, further, in step S1, the method for masking processing is as follows: multiply the masking function by the frequency-domain signal obtained by the fast Fourier transform to output a new frequency-domain signal.

[0014] In the present invention, further, in step S2, the method for using a band-pass filter to enhance the weight ratio of the central frequency band is as follows: identify the audio center frequency, define the frequency corresponding to the maximum amplitude in the spectrum as the center frequency, based on the center frequency, set the bandwidth of the central frequency band, call the band-pass filter, pass the original audio signal through the band-pass filter to enhance the signal in the central frequency band, and output a new frequency signal.

[0015] In the present invention, further, in step S3, the method for converting to Mel frequency is as follows: according to the Mel scale, convert the filtered signal through the Mel scale conversion to output the Mel frequency of the current music.

[0016] In the present invention, further, in step S4, the method for performing the key-style LED fade-in and fade-out is as follows: define a set of software logic in the vehicle lamp electronic driver, and evenly map the Mel frequency range output in step S3 in proportion to the LED lamp beads, so that each lamp bead corresponds to a Mel frequency range.

[0017] In the present invention, further, according to the characteristics that the high frequency changes gradually faster and the low frequency changes gradually slower, define the LED fade-in time and fade-out time for each interval in the vehicle lamp electronic driver software; when the vehicle lamp electronic driver receives the enabling signal of a certain LED, perform the corresponding LED fade-in and fade-out action.

[0018] In the present invention, further, the fade-in and fade-out time for each interval LED is 0.1 second - 3 seconds.

[0019] In the present invention, further, the fade-in and fade-out time for the high frequency interval LED is 0.1 - 0.5 seconds, the fade-in and fade-out time for the medium frequency interval LED is 0.5 - 2 seconds, and the fade-in and fade-out time for the low frequency interval LED is 2 - 3 seconds.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] 1. The present invention can effectively enhance the interactive experience between audio and vision by deeply analyzing and processing the frequency characteristics of music audio.

[0022] 2. The present invention can screen out key frequency components by performing mask processing on high and low frequency bands.

[0023] 3. The present invention can enhance the weight of the central frequency band and thus highlight the main features of music by identifying the central frequency of music and applying a band-pass filter.

[0024] 4. Based on the sensitivity of the human ear to frequency, the present invention uses the Mel scale for non-linear frequency variation, which can better adapt to the auditory characteristics of the human ear.

[0025] 5. According to the processed frequency information, the present invention configures the fade-in and fade-out time of the LED, performs a visual feedback action in the form of a piano key, not only enhances the expressiveness of the audio, but also enhances the user's immersion and participation through the visual effect, bringing a new dimension to the passenger experience.

[0026] 6. The present invention enables the LED to adopt an adaptive fade-in and fade-out mechanism, making the change of the light more linear and gentle, and not causing discomfort such as glare to the user. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the method flow of the present invention.

[0028] Figure 2 It is a schematic diagram of the frequency band clipping of the present invention.

[0029] Figure 3 It is an effect diagram of the filtered signal of the present invention.

[0030] Figure 4 It is a Mel scale diagram of the present invention.

[0031] Figure 5 It is a schematic diagram of the audio processing flow of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0033] Embodiment 1

[0034] Please refer to Figures 1 - 5, the present invention provides the following technical solution: A design method for a visual piano key rhythm light, comprising the following steps:

[0035] S1. Receive the vehicle body end music signal through an audio transceiver, read the audio information, and it is necessary to ensure that the set sampling rate is greater than twice the highest frequency, that is, satisfy the Nyquist sampling theorem, so as to realize the distortion-free restoration of the analog signal;

[0036] Use the Fast Fourier Transform (FFT) to convert the audio time-domain signal into a frequency-domain signal. The N points of the frequency-domain signal represent the amplitude and phase information at specific frequencies;

[0037] As shown in the Figure 2 specification appendix, among various musical instruments in nature, the piano can provide the highest frequency. Therefore, only the frequency range of 27HZ - 4186HZ is extracted from the collected music;

[0038] In the frequency domain, create a mask. The length of the mask is the same as the length of the FFT result. The values of the mask are set as follows: the mask values corresponding to the frequencies in the range of 27Hz to 4186Hz are set to 1; the mask values corresponding to the frequencies below 27Hz and above 4186Hz are set to 0;

[0039] Apply the created mask to the FFT result. By multiplying point by point, apply the mask to the frequency-domain signal to remove the unnecessary frequency components and retain the remaining frequency-domain signal characteristics;

[0040] S2. The frequency-domain signal characteristics include information such as the center frequency etc. Usually, the frequency corresponding to the maximum amplitude value in the signal is used as the center frequency. Design a band-pass filter, and determine the bandwidth near the center frequency according to the identified center frequency , that is, the frequency band range that needs to be enhanced. For example , since it is filtering for music, the bandwidth range can be set larger, otherwise some rare and unique timbre audio will be weakened;

[0041] The Butterworth band-pass filter can be used as an option to implement the band-pass filter. The band-pass filter allows signals within a specific frequency range to pass through, while Butterworth provides a smooth frequency response characteristic. A smooth frequency response means that there are no obvious spikes or fluctuations at the edges and in the middle of the passband, which helps to avoid introducing unnecessary distortion into the signal. As shown in the Figure 3 specification appendix, after the original signal passes through a band-pass filter BW=(300HZ - 1200HZ), the amplitude within its frequency band is enhanced, and the outside of the frequency band is weakened;

[0042] S3. As shown in the Figure 4The corresponding relationship between the Mel frequency and the natural frequency is as follows. The natural frequency range of 27HZ - 4186HZ will be converted into the following range after non-linear Mel transformation:

[0043]

[0044] ;

[0045] The filtered signal is converted through the Mel scale, which maps the enhanced frequencies in step S2 to the human ear sensitivity;

[0046] S4. Define a set of software logic in the headlight electronic driver. According to the Mel frequency range output in step S3, it is evenly mapped to the LED lamp beads in proportion, so that each lamp bead corresponds to a Mel frequency range;

[0047] According to the characteristics that the high frequency changes gradually faster and the low frequency changes gradually slower, define the LED gradual brightening time and the gradual dimming time for each interval in the headlight electronic driver software; when the headlight electronic driver receives the enabling signal of a certain LED, execute the corresponding LED gradual brightening and dimming actions;

[0048] The LED gradual brightening and dimming time for each interval is 0.1 second - 3 seconds. Specifically, the LED gradual brightening and dimming time for the high frequency interval is 0.1 - 0.5 seconds, the LED gradual brightening and dimming time for the medium frequency interval is 0.5 - 2 seconds, and the LED gradual brightening and dimming time for the low frequency interval is 2 - 3 seconds.

[0049] The time allocation table for LED gradual brightening and dimming is as follows:

[0050]

[0051] Example 2

[0052] Specifically, the band-pass filter needs to set the bandwidth , the center frequency , the gain coefficient , where

[0053] Bandwidth : It represents the frequency range allowed by the filter for the signal to pass through, and the signals within the range will be enhanced; around the center frequency , select the upper and lower boundaries, ; that is, the bandwidth ;

[0054] The transfer function of the band-pass filter can be expressed as:

[0055] ;

[0056] Among them, Denoted as the quality factor, it describes the gain or attenuation of a certain point frequency and the influence range on nearby frequencies. A high value represents a more precise selection of the filtering frequency band;

[0057] Multiply the Fourier transform result of the input signal by the transfer function of the band-pass filter to obtain the Fourier transform of the output signal, which is the music frequency-domain signal obtained after filtering:

[0058] .

[0059] In summary, through in-depth analysis and processing of the frequency characteristics of music audio, the present invention can effectively enhance the interactive experience between audio and vision; by performing masking processing on high and low frequency bands, the present invention can screen out key frequency components; by identifying the center frequency of music and applying a band-pass filter, the present invention can enhance the weight of the center frequency band, thereby highlighting the main features of music; based on the sensitivity of the human ear to frequencies, the present invention uses the Mel scale for non-linear frequency variation, which can better adapt to the auditory characteristics of the human ear; according to the processed frequency information, the present invention configures the fade-in and fade-out time of the LED and performs a key-like visual feedback action, which not only enhances the expressiveness of the audio, but also enhances the user's immersion and participation through visual effects, bringing a new dimension to the passenger experience.

[0060] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A design method for a visualized piano key rhythm light, characterized in that: The following steps are involved: S1. Mask the high and low frequency bands of the music audio to complete the frequency screening; S2, identify the center frequency of the music, and use a bandpass filter to increase the weight of the center frequency segment; S3, based on the characteristics of the sensitive area of ​​the human ear, the frequency is nonlinearly changed according to the Mel scale; S4. According to the obtained frequency information, the length of time for the LED to gradually light up and fade out is set, and the action of gradually lighting up and fading out the LED in a piano-key style is performed.

2. The design method of a visualized piano key rhythm lamp according to claim 1, characterized in that: In step S1, the method for audio frequency screening and processing is: receiving the music signal from the vehicle body through the audio transceiver, reading the audio information, sampling the music, using fast Fourier transform to convert the music from a time domain signal to a frequency domain signal, setting a mask function, setting the mask value within the selected frequency range to 1, and setting the mask value outside the range to 0.

3. The design method of a visualized piano key rhythm lamp according to claim 2, characterized in that: The selected frequency range is 27HZ-4186HZ.

4. The method for designing a visualized piano key rhythm lamp according to claim 2, characterized in that: In step S1, the mask processing method is: multiplying the mask function with the frequency domain signal obtained by fast Fourier transform to output a new frequency domain signal.

5. The design method of a visualized piano key rhythm lamp according to claim 1, characterized in that: In step S2, the method of using a bandpass filter to enhance the weight ratio of the center frequency band is as follows: identifying the center frequency of the audio, defining the frequency corresponding to the maximum amplitude in the spectrum as the center frequency, setting the bandwidth of the center frequency band based on the center frequency, calling the bandpass filter, passing the original audio signal through the bandpass filter, enhancing the signal of the center frequency band, and outputting a new frequency signal.

6. The method for designing a visualized piano key rhythm lamp according to claim 1, characterized in that: In the step S3, the method for converting the Mel frequency is: according to the Mel scale, the signal after filtering is converted to the Mel scale, and the Mel frequency of the current music is output.

7. The method for designing a visualized piano key rhythm lamp according to claim 6, characterized in that: In step S4, the method for executing the piano-key-like LED gradually turning on and off is: defining a set of software logic in the electronic driver of the vehicle light, and uniformly mapping the Mel frequency interval output in step S3 to the LED lamp beads in equal proportion, so that each lamp bead corresponds to a Mel frequency interval.

8. The method for designing a visualized piano key rhythm lamp according to claim 7, characterized in that: According to the characteristics of fast gradual change at high frequency and slow gradual change at low frequency, the LED gradual light-on time and gradual light-off time of each interval are defined in the electronic driver software of the headlight; When the electronic driver of the car light receives an LED enable signal, it executes the corresponding LED gradually turning on and off.

9. The method for designing a visualized piano key rhythm lamp according to claim 8, characterized in that: The time for the LED to gradually light up and fade out in each interval is 0.1 seconds to 3 seconds.

10. The method for designing a visualized piano key rhythm lamp according to claim 9, characterized in that: The time for the LED to gradually light up and fade out in the high-frequency range is 0.1-0.5 seconds, the time for the LED to gradually light up and fade out in the medium-frequency range is 0.5-2 seconds, and the time for the LED to gradually light up and fade out in the low-frequency range is 2-3 seconds.

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