Photographing apparatus circuit, shutter frequency adjustment method for photographing apparatus, and photographing apparatus

Abstract

The application discloses a kind of photographic equipment circuit, shutter frequency adjustment method and photographic equipment of photographic equipment, it is related to photoelectric technology field, photographic equipment circuit includes control circuit, light signal acquisition circuit, direct current separation circuit and amplification circuit, by above-mentioned setting, light signal in ambient light is collected and is converted into first electric signal, after direct current separation circuit and amplification circuit, by control circuit determine first frequency, when first frequency is in preset frequency range, control circuit automatically adjusts the shutter frequency of photographic equipment to the first frequency or its frequency multiplication;When first frequency is not in preset frequency range, shutter frequency is not adjusted.The technical scheme provided by the application can improve the picture flicker problem caused by the shutter frequency of photographic equipment and light source frequency out of synchronization, automatically identify power line frequency to eliminate power frequency flicker, while reducing cost.

Description

Technical Field

[0001] This invention relates to the field of optoelectronic technology, and in particular to a photographic equipment circuit, a method for adjusting the shutter frequency of a photographic equipment, and a photographic equipment. Background Technology

[0002] Currently, live streaming cameras and conferencing cameras commonly face the problem of light source flicker. When the camera shutter frequency is out of sync with the periodic changes in AC power, bright and dark stripes or flickering phenomena appear in the captured image, affecting video quality. Existing technologies mainly use manual management, zero-crossing detection, and phase difference methods to solve this problem. However, manual management requires different software versions for different regions, which cannot be unified and requires repeated manual adjustments when used across regions, resulting in poor management costs and user experience. Zero-crossing detection is sensitive to noise and requires multiple consecutive cycles to obtain stable results, resulting in a slow response speed. The phase difference method suffers a significant decrease in accuracy under signal distortion or noise interference. Summary of the Invention

[0003] The main objective of this invention is to propose a photographic equipment circuit and photographic equipment, which aims to improve the problem of image flicker caused by the asynchronous shutter frequency and light source frequency of the photographic equipment, automatically identify the power line frequency to eliminate power frequency flicker, and at the same time reduce costs.

[0004] To achieve the above objectives, the present invention provides a photographic device circuit comprising: Control circuit; An optical signal acquisition circuit, wherein the optical signal acquisition circuit acquires optical signals in ambient light and converts the optical signals into a first electrical signal; A DC blocking circuit, wherein the input terminal of the DC blocking circuit is connected to the output terminal of the optical signal acquisition circuit; An amplifier circuit, wherein the input terminal of the amplifier circuit is connected to the output terminal of the DC blocking circuit, and the output terminal of the amplifier circuit is connected to the control circuit; the amplifier circuit is used to convert the first electrical signal into a second electrical signal. The control circuit is used to determine a first frequency of the optical signal based on the second electrical signal; When the first frequency is within a preset frequency range, the control circuit controls the shutter frequency of the photographic device to be adjusted to the first frequency or a multiple of the first frequency. When the first frequency is not within the preset frequency range, the shutter frequency of the photographic equipment will not be adjusted.

[0005] In one embodiment, the optical signal acquisition circuit includes a first resistor and a photoelectric converter; The first end of the first resistor is connected to the power supply terminal, the second end of the first resistor is connected to the first end of the photoelectric converter, and the second end of the photoelectric converter is grounded. The photoelectric converter is used to convert the optical signal into an electrical signal.

[0006] In one embodiment, the DC blocking circuit includes a first capacitor; The first terminal of the first capacitor is connected to the second terminal of the first resistor and the first terminal of the photoelectric converter, respectively, and the second terminal of the first capacitor is connected to the amplifier circuit.

[0007] In one embodiment, the amplification circuit includes a second resistor, a third resistor, a fourth resistor, and an amplification transistor; The first end of the second resistor is connected to the power supply terminal, the second end of the second resistor and the first end of the third resistor are respectively connected to the output terminal of the DC blocking circuit, the second end of the third resistor is grounded, the first end of the fourth resistor is connected to the power supply terminal, and the second end of the fourth resistor is connected to the first end of the amplifying transistor. The input terminal of the amplifying transistor is connected to the output terminal of the DC blocking circuit, and the second terminal of the amplifying transistor is grounded.

[0008] In one embodiment, the first frequency is 100Hz or 120Hz.

[0009] The present invention also proposes a method for adjusting the shutter frequency of a photographic device, the method comprising: Acquire optical signals from ambient light and convert the optical signals into a first electrical signal; The first electrical signal is subjected to DC blocking to obtain a DC-blocked electrical signal; The DC-blocked electrical signal is amplified to obtain a second electrical signal, and the first frequency of the optical signal is determined based on the second electrical signal. Determine whether the first frequency is within a preset frequency range; When the first frequency is within the preset frequency range, the shutter frequency of the photographic device is controlled to be adjusted to the first frequency or a multiple of the first frequency; When the first frequency is not within the preset frequency range, the shutter frequency of the camera is not adjusted.

[0010] In one embodiment, determining the first frequency of the optical signal based on the second electrical signal includes: The second electrical signal is converted from analog to digital to obtain a digital signal; Perform a Fourier transform on the digital signal to convert the time-domain signal into a frequency-domain signal, and extract the peak frequency in the frequency domain as the first frequency.

[0011] In one embodiment, the method further includes: Before determining that the first frequency is within the preset frequency range, the first frequency is detected multiple times; When the results of the multiple tests meet the judgment criteria, the shutter frequency of the photographic device is adjusted.

[0012] In one embodiment, the condition for satisfying the determination is that at least three of the five detections detect the first frequency within the same preset frequency range.

[0013] The present invention also proposes a photographic device including the photographic device circuitry as described in any of the preceding claims; or, the photographic device includes a control device for storing and executing the shutter frequency adjustment method as described in any of the preceding claims.

[0014] The technical solution of this invention includes a control circuit, a light signal acquisition circuit, a DC blocking circuit, and an amplification circuit. The light signal acquisition circuit acquires light signals from ambient light and converts the light signals into a first electrical signal. The input terminal of the DC blocking circuit is connected to the output terminal of the light signal acquisition circuit. The input terminal of the amplification circuit is connected to the output terminal of the DC blocking circuit, and the output terminal of the amplification circuit is connected to the control circuit. The amplification circuit is used to convert the first electrical signal into a second electrical signal. The control circuit is used to determine a first frequency of the light signal based on the second electrical signal. When the first frequency is within a preset frequency range, the control circuit controls the shutter frequency of the photographic device to adjust to the first frequency or a multiple of the first frequency. When the first frequency is not within the preset frequency range, the shutter frequency of the photographic device is not adjusted.

[0015] Thus, through the above settings, the light signal in the ambient light is collected and converted into a first electrical signal. After passing through a DC blocking circuit and an amplification circuit, the control circuit determines the first frequency. When the first frequency is within the preset frequency range, the control circuit automatically adjusts the shutter frequency of the photographic equipment to the first frequency or its multiples, thereby effectively improving the image flicker caused by the asynchronous frequency of the shutter and the light source, and realizing automatic adaptation of the power line frequency in different regions. When the first frequency is not within the preset frequency range, the shutter frequency is not adjusted. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 This is a structural block diagram of an embodiment of the photographic device circuit provided by the present invention; Figure 2A circuit diagram of another embodiment of the photographic device circuit provided by the present invention; Figure 3 A flowchart of yet another embodiment of the photographic device circuit provided by the present invention; Figure 4 A flowchart of an embodiment of the shutter frequency adjustment method for photographic equipment provided by the present invention; Figure 5 A flowchart of yet another embodiment of the shutter frequency adjustment method for photographic equipment provided by the present invention.

[0018] Explanation of icon numbers: 100. Circuitry of photographic equipment; 10. Control circuit; 20. Optical signal acquisition circuit; 30. DC blocking circuit; 40. Amplification circuit.

[0019] R1, first resistor; PT1, photoelectric converter; C1, first capacitor; R2, second resistor; R3, third resistor; R4, fourth resistor; Q1, amplifying transistor.

[0020] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not 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 effort are within the scope of protection of the present invention.

[0022] Currently, live streaming cameras and conferencing cameras commonly face the problem of light source flicker. When the camera shutter frequency is out of sync with the periodic changes in AC power, bright and dark stripes or flickering phenomena appear in the captured image, affecting video quality. Existing technologies mainly use manual management, zero-crossing detection, and phase difference methods to solve this problem. However, manual management requires different software versions for different regions, which cannot be unified and requires repeated manual adjustments when used across regions, resulting in poor management costs and user experience. Zero-crossing detection is sensitive to noise and requires multiple consecutive cycles to obtain stable results, resulting in a slow response speed. The phase difference method suffers a significant decrease in accuracy under signal distortion or noise interference.

[0023] When a camera uses a rolling shutter to photograph AC-powered lights, the fundamental reason for the appearance of bright and dark stripes or flickering in the image is that the shutter frequency is not matched with the periodic changes in the light's brightness. Taking a common fluorescent lamp as an example, the periodic changes in AC power cause the light's brightness to alternate between bright and dark at a certain frequency. If the camera uses a rolling shutter with line-by-line exposure, the exposure start times for each line of the image sensor are not the same, but are staggered from top to bottom. When the shutter frequency is not an integer multiple of the light flicker period, the proportion of bright and dark phases covered by each row of pixels will differ—some rows encounter longer bright periods during exposure, while others encounter more dark periods. The accumulated light in each row is therefore uneven, ultimately appearing as horizontal stripes or overall flickering in the image. Conversely, if the shutter frequency is an integer multiple of the light flicker period, each row can completely cover an integer number of bright and dark cycles, and the total amount of light received by each row tends to be consistent, resulting in a uniform and stable image. Therefore, as long as the shutter speed cannot be synchronized with the periodic changes in the light, stripes will occur, thus degrading video quality.

[0024] To address this issue, the present invention proposes a photographic equipment circuit designed to improve the problem of image flicker caused by the asynchronous shutter frequency and light source frequency of the photographic equipment. This circuit automatically identifies the power line frequency to eliminate power frequency flicker while reducing costs.

[0025] Please see Figure 1 and Figure 2 In one embodiment of the present invention, the photographic device circuit 100 includes: Control circuit 10; The optical signal acquisition circuit 20 acquires the optical signal in the ambient light and converts the optical signal into a first electrical signal. DC blocking circuit 30, the input terminal of DC blocking circuit 30 is connected to the output terminal of optical signal acquisition circuit; Amplifier circuit 40, the input terminal of amplifier circuit 40 is connected to the output terminal of DC blocking circuit 30, and the output terminal of amplifier circuit 40 is connected to control circuit 10; amplifier circuit 40 is used to convert the first electrical signal into a second electrical signal; Control circuit 10 is used to determine the first frequency of the optical signal based on the second electrical signal; When the first frequency is within a preset frequency range, the control circuit 10 controls the shutter frequency of the photographic device to be adjusted to the first frequency or a multiple of the first frequency. When the first frequency is not within the preset frequency range, the shutter frequency of the photographic equipment will not be adjusted.

[0026] In this embodiment, a photographic equipment circuit is provided. This circuit can be built into photographic equipment such as live streaming cameras, conference cameras, or digital video cameras with video shooting functions. It is used to automatically detect the ambient light flicker frequency and adjust the shutter speed accordingly, thereby eliminating the bright and dark stripes or flickering phenomenon on the screen caused by the flicker of AC light sources.

[0027] Optionally, the photographic equipment circuit mainly includes: a light signal acquisition circuit 20, a DC blocking circuit 30, an amplification circuit 40, and a control circuit 10. The light signal acquisition circuit 20 is used to acquire light signals from ambient light and convert them into a first electrical signal. The input terminal of the DC blocking circuit 30 is connected to the output terminal of the light signal acquisition circuit 20, and it is used to filter out the DC component in the first electrical signal. The input terminal of the amplification circuit 40 is connected to the output terminal of the DC blocking circuit 30, and it is used to amplify the DC-blocked signal into a second electrical signal. The output terminal of the amplification circuit 40 is connected to the control circuit 10. The control circuit 10 determines a first frequency of the light signal based on the second electrical signal, and decides whether to adjust the shutter frequency of the photographic equipment based on whether the first frequency is within a preset frequency range. Specifically, when the first frequency is within the preset frequency range, the control circuit 10 controls the shutter frequency of the photographic equipment to adjust to the first frequency or an integer multiple of the first frequency; when the first frequency is not within the preset frequency range, the control circuit 10 does not adjust the shutter frequency and maintains the original state.

[0028] Optionally, the optical signal acquisition circuit 20 includes a first resistor R1 and a photoelectric converter PT1, which can be a photodiode, a photosensitive diode, or a phototransistor. The first terminal of the first resistor R1 is connected to the power supply terminal VCC (e.g., a +3.3V or +5V DC power supply), and the second terminal of the first resistor R1 is connected to the first terminal of the photoelectric converter PT1, which is grounded. When ambient light shines on the photoelectric converter PT1, a weak photocurrent proportional to the light intensity is generated inside the photoelectric converter PT1. This photocurrent flows through the first resistor R1, forming a voltage signal, i.e., a first electrical signal, at the second terminal of the first resistor R1 that varies with the light intensity. The first electrical signal contains both the constant background component of the ambient light (DC component) and the fluctuating component caused by the flicker of the light source (AC component).

[0029] Optionally, the DC blocking circuit 30 is preferably implemented using a first capacitor C1 to filter out the DC component in a simple and low-cost manner. The first terminal of the first capacitor C1 is connected to the second terminal of the first resistor R1 and the first terminal of the photoelectric converter PT1, respectively. The second terminal of the first capacitor C1 serves as the output terminal of the DC blocking circuit 30 and is connected to the amplifier circuit 40. Since the first capacitor C1 has an open-circuit characteristic for DC signals, the DC component in the first electrical signal is blocked; while for AC components, the first capacitor C1 presents a low impedance, allowing AC signals reflecting changes in ambient light and darkness to pass smoothly, thus obtaining the DC-blocked electrical signal. The DC-blocked electrical signal mainly characterizes the flicker waveform of the light source. For example, under a 50Hz AC-driven fluorescent lamp, the signal appears as a sine wave of approximately 100Hz; under a 60Hz AC-driven fluorescent lamp, it appears as a sine wave of approximately 120Hz.

[0030] Optionally, the amplifier circuit 40 employs a common-emitter transistor amplification structure. Specifically, the amplifier circuit 40 includes a second resistor R2, a third resistor R3, a fourth resistor R4, and an amplifying transistor Q1, which can be an NPN transistor. The first terminal of the second resistor R2 is connected to the power supply terminal VCC, and the second terminals of both the second and third resistors R3 are connected to the output terminal of the DC blocking circuit 30, i.e., the second terminal of the first capacitor C1. The second terminal of the third resistor R3 is grounded. The first terminal of the fourth resistor R4 is connected to the power supply terminal VCC, and the second terminal of the fourth resistor R4 is connected to the collector (first terminal) of the transistor. The base (input terminal) of the transistor is connected to the output terminal of the DC blocking circuit 30, and the emitter (second terminal) of the transistor is grounded. By appropriately selecting the ratio of the second resistor R2 and the third resistor R3, the DC bias point of the amplifier circuit 40 can be set. The fourth resistor R4 acts as a load resistor, converting changes in the transistor's collector current into voltage changes. The common-emitter amplifier circuit 40 can amplify an AC signal with an amplitude of only millivolts after DC blocking to the volt level (e.g., 0-3.3V), and output a second electrical signal to meet the input requirements of the analog-to-digital conversion interface of the subsequent control circuit 10.

[0031] Optionally, the control circuit 10 can be a microcontroller (MCU), a digital signal processor (DSP), or other chip integrating an analog-to-digital converter (ADC) and an arithmetic unit. After receiving the second electrical signal, the control circuit 10 first converts it into a digital signal using its internal ADC; then, it performs a Fast Fourier Transform (FFT) on the digital signal to transform the time-domain waveform to the frequency domain, extracting the frequency component with the largest amplitude in the spectrum as the first frequency of the optical signal. The internal memory of the control circuit 10 stores preset frequency ranges, for example, a first preset range of 99.5Hz to 100.5Hz and a second preset range of 119.5Hz to 120.5Hz. If the extracted first frequency falls within the range of 99.5Hz to 100.5Hz, the control circuit 10 determines that the current ambient light flicker frequency is 100Hz (corresponding to a 50Hz AC mains power), and then sends a control signal to the shutter drive module of the photographic equipment to adjust the shutter frequency to match the 50Hz frequency. If the first frequency falls within the range of 119.5Hz to 120.5Hz, it is determined to be 120Hz (corresponding to a 60Hz AC mains power), and the shutter frequency is adjusted to match the 60Hz frequency. If the first frequency is not within any of the above preset ranges (e.g., less than 80Hz or greater than 140Hz), the control circuit 10 does not send an adjustment signal, and the shutter remains at its original setting.

[0032] In one example, the first frequency is 100Hz or 120Hz. For instance, a user is traveling from China (50Hz power grid) to the United States (60Hz power grid) on a business trip with a live-streaming camera. Upon arrival in the US, they start a live stream under the hotel's indoor lighting, which is driven by 60Hz AC power, resulting in an actual flicker frequency of 120Hz. Previously, when the camera was used in China, its shutter frequency was automatically adjusted to match the 50Hz frequency. Because the flicker period at 120Hz is shorter, the camera's progressive exposure is out of sync with the phase of the lighting, causing the live stream to display stripes and periodic flickering, affecting the viewing experience. If the camera incorporates the photographic equipment circuit 100 of this invention, it will detect the ambient light flicker frequency upon power-on, collect and analyze the signal through the light signal acquisition circuit 20, identify the flicker frequency as 120Hz, and automatically determine that the local power line frequency is 60Hz. The camera's shutter frequency will then automatically adjust to match the 60Hz frequency, eliminating the stripes and flickering without manual intervention. It is evident that the frequency of the power line directly determines the flicker frequency of the lamp (a 2:1 relationship), and the flicker frequency of the lamp, in turn, determines the shutter parameters that the camera needs to match. This invention deduces the power line frequency by detecting the flicker frequency of the light, thereby automatically eliminating flicker in any region and ensuring video quality.

[0033] The technical solution of the present invention includes a control circuit 10, a light signal acquisition circuit 20, a DC blocking circuit 30, and an amplification circuit 40. The light signal acquisition circuit 20 acquires light signals from ambient light and converts the light signals into a first electrical signal. The input terminal of the DC blocking circuit 30 is connected to the output terminal of the light signal acquisition circuit 20. The input terminal of the amplification circuit 40 is connected to the output terminal of the DC blocking circuit 30, and the output terminal of the amplification circuit 40 is connected to the control circuit 10. The amplification circuit 40 is used to convert the first electrical signal into a second electrical signal. The control circuit 10 is used to determine a first frequency of the light signal based on the second electrical signal. When the first frequency is within a preset frequency range, the control circuit 10 controls the shutter frequency of the photographic device to adjust to the first frequency or a multiple of the first frequency. When the first frequency is not within the preset frequency range, the shutter frequency of the photographic device is not adjusted.

[0034] Thus, through the above settings, the light signal in the ambient light is collected and converted into a first electrical signal. After passing through the DC blocking circuit 30 and the amplification circuit 40, the first frequency is determined by the control circuit 10. When the first frequency is within the preset frequency range, the control circuit 10 automatically adjusts the shutter frequency of the photographic equipment to the first frequency or its multiples, thereby effectively improving the image flicker caused by the asynchronous frequency of the shutter and the light source, and realizing automatic adaptation of the power line frequency in different regions. When the first frequency is not within the preset frequency range, the shutter frequency is not adjusted.

[0035] like Figure 3 and Figure 4 As shown, the present invention also proposes a method for adjusting the shutter frequency of a photographic device, the method comprising: Step S100: Collect the light signal in the ambient light and convert the light signal into a first electrical signal; Step S200: Perform DC blocking processing on the first electrical signal to obtain the DC-blocked electrical signal; Step S300: Amplify the DC-blocked electrical signal to obtain a second electrical signal, and determine the first frequency of the optical signal based on the second electrical signal; Step S400: Determine whether the first frequency is within the preset frequency range; Step S410: When the first frequency is within the preset frequency range, control the shutter frequency of the camera to be adjusted to the first frequency or a multiple of the first frequency. Step S420: When the first frequency is not within the preset frequency range, the shutter frequency of the camera is not adjusted.

[0036] This embodiment provides a method for adjusting the shutter frequency of a photographic device, which can automatically eliminate bright and dark stripes or flickering in the image caused by the flickering of AC light sources. The photographic device collects light signals from ambient light through a built-in photoelectric converter PT1 and converts the light signals into a first electrical signal. Since ambient light often contains a constant background light component, the first electrical signal will contain a DC component. This DC component does not reflect the flickering information of the light source and may interfere with subsequent processing. Therefore, the first electrical signal needs to be DC blocked. Specifically, the DC component can be filtered out by connecting a DC blocking capacitor in series, retaining only the AC component, thus obtaining a DC-blocked electrical signal. The amplitude of the DC-blocked electrical signal is usually small and difficult to use directly by analog-to-digital conversion or frequency analysis circuits, so it needs to be further amplified. The amplification circuit in the photographic device circuit (e.g., a common-emitter amplifier circuit composed of transistors and resistors, or a non-inverting amplifier circuit composed of operational amplifiers) amplifies the DC-blocked electrical signal and outputs a second electrical signal. Subsequently, the first frequency of the light signal is determined based on the second electrical signal.

[0037] Optionally, a preferred implementation involves first performing analog-to-digital conversion on the second electrical signal to obtain a digital signal, then performing a Fast Fourier Transform on the digital signal to convert the time-domain signal into a frequency-domain signal, and extracting the peak frequency in the frequency domain as the first frequency. This first frequency is the actual flicker frequency of the ambient light source; for example, under a 50Hz AC-driven fluorescent lamp, the first frequency is approximately 100Hz; under a 60Hz AC-driven fluorescent lamp, the first frequency is approximately 120Hz. After obtaining the first frequency, the control circuit 10 of the photographic equipment determines whether the first frequency falls within a pre-stored preset frequency range. This preset frequency range can be set according to the power grid standards of major regions worldwide; for example, the first preset range is set to 99.5Hz–100.5Hz (corresponding to a 50Hz power grid), and the second preset range is set to 119.5Hz–120.5Hz (corresponding to a 60Hz power grid). If the first frequency falls within any of the above preset ranges, the control circuit controls the shutter frequency of the photographic equipment to adjust to the first frequency or an integer multiple of the first frequency. For example, when the first frequency is 100.2Hz, the shutter frequency can be adjusted to match 50Hz, thereby ensuring that the exposure time of each line of the image sensor covers an integer number of flicker cycles, eliminating stripes. If the first frequency is not within any preset range, for example, if the detection value deviates significantly (such as 80Hz or 140Hz), it is determined that the current ambient light may come from a non-AC driven light source (such as natural light or DC LED light) or that the detection is interfered with. In this case, the control circuit will not make any adjustment to the shutter frequency to avoid incorrect adaptation that could lead to image quality degradation.

[0038] like Figure 3 and Figure 5 As shown, in one embodiment, the method further includes: Step S500: Before determining that the first frequency is within the preset frequency range, the first frequency is detected multiple times; Step S600: When the multiple detection results meet the judgment conditions, adjust the shutter frequency of the photography device.

[0039] Optionally, in order to further improve the reliability of frequency recognition and avoid incorrect adjustment of shutter frequency due to single misjudgment caused by instantaneous noise, brief obstruction or occasional interference, this embodiment adds multiple detection and condition judgment steps before determining whether the first frequency is within the preset frequency range.

[0040] Specifically, after the photographic equipment completes the light signal acquisition, DC blocking, amplification, and frequency extraction operations to obtain the first frequency, it does not immediately compare the first frequency with a preset frequency range to decide whether to adjust the shutter speed. Instead, it temporarily stores the detection result in the memory. Subsequently, the photographic equipment repeats the above-mentioned complete detection process at multiple different time points to obtain multiple detection values ​​of the first frequency. The time interval between two adjacent detections can be set according to actual needs, such as performing a detection every 0.2 seconds, 0.5 seconds, or 1 second, to balance detection speed and anti-interference capability. After completing a preset number of detections, the control circuit 10 judges the multiple detection results obtained to check whether they meet the preset judgment conditions.

[0041] In this embodiment, the determination condition is as follows: in a total of 5 detections, at least 3 of the detected first frequencies fall within the same preset frequency range (for example, all within the range of 99.5Hz to 100.5Hz, or all within the range of 119.5Hz to 120.5Hz). Once this condition is met, the control circuit 10 determines that the current ambient light flicker frequency is stable and reliable, and performs a shutter frequency adjustment operation; if this condition is not met (for example, only 2 or fewer of the 5 detections fall within the same preset range, or the detection results are scattered in different ranges), no adjustment is made this time, the photographic device maintains the original shutter frequency setting, and the multiple detection process restarts in the next detection cycle.

[0042] For example, in five detections, the measured values ​​are 100.1Hz, 99.9Hz, 100.2Hz, 120.1Hz, and 100.0Hz. Four of these values ​​fall within the 99.5Hz to 100.5Hz range (100.1, 99.9, 100.2, 100.0), meeting the threshold of three occurrences. Therefore, the judgment condition is met, and the control circuit adjusts the shutter frequency of the photographic equipment to match 50Hz. Conversely, if the five detection values ​​are 100.1Hz, 99.9Hz, 120.2Hz, 120.0Hz, and 85.0Hz, then two values ​​fall within the 100Hz range, and two fall within the 120Hz range, neither meeting the three-times threshold. Therefore, the judgment condition is not met, and the shutter frequency is not adjusted. Through the above-mentioned multiple detection and condition judgment mechanism, accidental errors caused by factors such as brief hand obstruction, sudden flickering of other nearby light sources, or instantaneous circuit noise can be effectively eliminated, significantly improving the robustness and accuracy of frequency recognition and shutter adjustment.

[0043] Alternatively, the control device can be implemented using a main controller, such as a System On Chip (SOC), Microcontroller Unit (MCU), Digital Signal Processor (DSP), or Field Programmable Gate Array (FPGA).

[0044] The present invention also proposes a photographic device, which includes any of the photographic device circuits 100 described above; or the photographic device includes a control device for storing and executing shutter frequency adjustment as described above. The specific structure of the photographic device circuit 100 is as described in the above embodiments. It is worth noting that since the photographic device includes the photographic device circuit 100 and the control device for executing the shutter frequency adjustment method, the photographic device of the present invention also includes all the embodiments of the photographic device circuit 100 and the shutter frequency adjustment method described above, as well as the effects of each embodiment, which will not be repeated here.

[0045] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention specification and drawings under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A photographic equipment circuit, characterized in that, The photographic equipment circuitry includes: Control circuit; An optical signal acquisition circuit, wherein the optical signal acquisition circuit acquires optical signals in ambient light and converts the optical signals into a first electrical signal; A DC blocking circuit, wherein the input terminal of the DC blocking circuit is connected to the output terminal of the optical signal acquisition circuit; An amplifier circuit, wherein the input terminal of the amplifier circuit is connected to the output terminal of the DC blocking circuit, and the output terminal of the amplifier circuit is connected to the control circuit; the amplifier circuit is used to convert the first electrical signal into a second electrical signal. The control circuit is used to determine a first frequency of the optical signal based on the second electrical signal; When the first frequency is within a preset frequency range, the control circuit controls the shutter frequency of the photographic device to be adjusted to the first frequency or a multiple of the first frequency. When the first frequency is not within the preset frequency range, the shutter frequency of the photographic equipment will not be adjusted.

2. The photographic equipment circuit as described in claim 1, characterized in that, The optical signal acquisition circuit includes a first resistor and a photoelectric converter; The first end of the first resistor is connected to the power supply terminal, the second end of the first resistor is connected to the first end of the photoelectric converter, and the second end of the photoelectric converter is grounded. The photoelectric converter is used to convert the optical signal into an electrical signal.

3. The photographic equipment circuit as described in claim 2, characterized in that, The DC blocking circuit includes a first capacitor; The first terminal of the first capacitor is connected to the second terminal of the first resistor and the first terminal of the photoelectric converter, respectively, and the second terminal of the first capacitor is connected to the amplifier circuit.

4. The photographic equipment circuit as described in claim 1, characterized in that, The amplifier circuit includes a second resistor, a third resistor, a fourth resistor, and an amplifying transistor; The first end of the second resistor is connected to the power supply terminal, the second end of the second resistor and the first end of the third resistor are respectively connected to the output terminal of the DC blocking circuit, the second end of the third resistor is grounded, the first end of the fourth resistor is connected to the power supply terminal, and the second end of the fourth resistor is connected to the first end of the amplifying transistor. The input terminal of the amplifying transistor is connected to the output terminal of the DC blocking circuit, and the second terminal of the amplifying transistor is grounded.

5. The photographic equipment circuit as described in claim 1, characterized in that, The first frequency is 100Hz or 120Hz.

6. A method for adjusting the shutter frequency of a photographic device, characterized in that, The method includes: Acquire optical signals from ambient light and convert the optical signals into a first electrical signal; The first electrical signal is subjected to DC blocking to obtain a DC-blocked electrical signal; The DC-blocked electrical signal is amplified to obtain a second electrical signal, and the first frequency of the optical signal is determined based on the second electrical signal. Determine whether the first frequency is within a preset frequency range; When the first frequency is within the preset frequency range, the shutter frequency of the photographic device is controlled to be adjusted to the first frequency or a multiple of the first frequency; When the first frequency is not within the preset frequency range, the shutter frequency of the camera is not adjusted.

7. The shutter frequency adjustment method for a photographic device as described in claim 6, characterized in that, Determining the first frequency of the optical signal based on the second electrical signal includes: The second electrical signal is converted from analog to digital to obtain a digital signal; Perform a Fourier transform on the digital signal to convert the time-domain signal into a frequency-domain signal, and extract the peak frequency in the frequency domain as the first frequency.

8. The shutter frequency adjustment method for a photographic device as described in claim 6, characterized in that, The method further includes: Before determining that the first frequency is within the preset frequency range, the first frequency is detected multiple times; When the results of the multiple tests meet the judgment criteria, the shutter frequency of the photographic device is adjusted.

9. The shutter frequency adjustment method for a photographic device as described in claim 8, characterized in that, The condition for satisfying the judgment is that the first frequency detected in at least 3 out of 5 detections is within the same preset frequency range.

10. A photographic device, characterized in that, The photographic equipment includes: The photographic device circuit as described in any one of claims 1 to 5; Alternatively, the photographic device includes a control unit for storing and executing the shutter frequency adjustment method as described in any one of claims 6 to 9.

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