CN103581663B - The method of testing of circuit board and system - Google Patents

Abstract

The method of testing of circuit board and a system, described circuit board is suitable for carrying out demodulation process to the TV signal received, to obtain audio output signal and video output signals; Described method of testing comprises: send scheduled television signal to described circuit board, described scheduled television signal is obtained by predetermined image signal and predetermined audio signal madulation; Described predetermined audio signal is utilized to test the audio output signal that described circuit board exports; Described predetermined image signal is utilized to test the video output signals that described circuit board exports.Technical scheme of the present invention achieves the test of automation, improves testing efficiency and test coverage, reduces testing cost.

Description

Circuit board testing method and system

technical field

The invention relates to the technical field of testing, in particular to a circuit board testing method and system.

Background technique

With the advancement of technology, more and more electronic products have the function of playing analog TV or digital TV. For example: mobile phones, MP4, car equipment, handheld devices, palmtop computers, etc. Electronic products watch TV programs through their built-in TV chips, such as digital TV chips or analog TV chips. Generally speaking, TV chips and other chips (control chips, processors) of electronic products will be integrated on one circuit board. Taking mobile phones as an example, digital TV chips and baseband chips of mobile phones are usually integrated on one circuit board. Digital TV The chip realizes the demodulation of the TV signal, and sends the demodulated signal to the baseband chip for subsequent processing, such as: the baseband chip decodes the demodulated TV signal, etc.

When electronic products are mass-produced, the function or performance of electronic products will be tested at the production site to verify whether the electronic products produced meet the expected quality requirements. At the same time, problems in the production process and product functions and performance can be found. Defects, such as whether the chip is soldered or invalid. Circuit boards with integrated TV chips are no exception and need to be tested as well.

In the prior art, the circuit board integrated with the TV chip is usually tested in the following two ways:

The first method: connect the TV signal generator to the circuit board under test through RF cables or wirelessly, and use the computer to read the correlation in the TV chip (analog TV chip or digital TV chip) through the main control chip of the circuit board under test. The data in the register is used to detect whether the TV chip is normal in terms of receiving TV signal strength and demodulating TV signal. In order to judge whether the TV function of the circuit board under test is normal. By testing the circuit board in this way, both the performance and the function of the circuit board can be tested, and the test of the radio frequency performance of the TV chip is relatively accurate, and the entire test process can be automatically completed under the control of the computer. However, the high price of the TV signal generator leads to high test cost, and this test method cannot accurately determine whether the connection between the TV chip and the main control chip is correct when transmitting image data signals.

The second method is to test manually. Specifically, the circuit board under test receives the TV signal sent by the TV station through manual operation such as button operation, so that the circuit board under test enters the "TV broadcast" state, and the image is observed by human eyes , The way the human ear listens to the sound manually judges whether the TV function of the circuit board is normal. Although this way of testing saves the cost of configuring the TV signal generator, when using manual testing, on the one hand, the test coverage and test efficiency are low, and the test results are inaccurate; As the number increases, testers also need to increase accordingly, which will also lead to an increase in testing costs to a certain extent.

Therefore, for the circuit board integrated with the TV chip, how to provide a test method with low test cost, high test efficiency and high coverage has become one of the problems to be solved urgently.

For other related technologies related to TV chips, please refer to the US patent application with the publication number US2009190656A1 and the invention name is Television Functionality on a Chip.

Contents of the invention

The problem solved by the invention is to provide a method and system for testing circuit boards with high test efficiency and test coverage and low test cost.

In order to solve the above problems, the present invention provides a method for testing a circuit board, which is suitable for demodulating a received television signal to obtain an audio output signal and a video output signal; the test method includes: Sending a predetermined TV signal to the circuit board, the predetermined TV signal is modulated by a predetermined image signal and a predetermined audio signal; using the predetermined audio signal to test the audio output signal output by the circuit board; using the predetermined image The signal tests the video output signal output by the circuit board.

Optionally, using the predetermined audio signal to test the audio output signal output by the circuit board includes: transforming the audio output signal from the time domain to the frequency domain; The energy of the effective signal and the energy of the noise signal in the audio output signal; calculate the energy ratio of the effective signal and the noise signal to obtain the signal-to-noise ratio of the audio output signal; compare the signal-to-noise ratio with the preset signal Noise Ratio Threshold.

Optionally, using the predetermined image signal to test the video output signal output by the circuit board includes: using pixel parameters of the predetermined image signal to test the video output signal.

Optionally, the testing the video output signal by using the pixel parameters of the predetermined image signal includes: determining based on the pixel parameters of a frame of image in the video output signal and the corresponding pixel parameters in the predetermined image signal An error parameter; comparing the error parameter with a preset error threshold.

Optionally, using the predetermined image signal to test the video output signal output by the circuit board includes: using a characteristic parameter of the predetermined image signal to test the video output signal.

Optionally, the testing of the video output signal by using the characteristic parameters of the predetermined image signal includes: using an image recognition algorithm to identify text and/or graphics of a frame of image in the video signal; matching the recognized text and/or graphics correspond to text and/or graphics in the predetermined image signal.

In order to solve the above problems, the present invention also provides a test system for a circuit board, the circuit board is suitable for demodulating the received TV signal to obtain an audio output signal and a video output signal; the test system includes : a sending unit, used to send a predetermined TV signal to the circuit board, the predetermined TV signal is obtained by modulation of a predetermined image signal and a predetermined audio signal; an audio test unit, used to output the predetermined audio signal to the circuit board The audio output signal is tested; the video test unit is used to use the predetermined image signal to test the video output signal output by the circuit board.

Compared with the prior art, the technical solution of the present invention has the following advantages:

The circuit board receives a predetermined TV signal modulated by a predetermined image signal and a predetermined audio signal, and then uses the predetermined audio signal, that is, a known audio signal, to test the audio output signal output by the circuit board after demodulating and processing the predetermined circuit signal and using the predetermined video signal, that is, a known video signal, to test the video output signal output by the circuit board after demodulating and processing the predetermined circuit signal, so as to realize the test of the audio and video function of the circuit board. Because there is no need to generate TV signals through TV signal generators, the cost of testing is greatly reduced. Moreover, since it is not necessary to judge whether the function of the circuit board is normal through a manual method, automated testing is realized, and testing efficiency and testing coverage are also improved.

When using the predetermined image signal to test the video output signal output by the circuit board, the circuit board can be tested by comparing the parameter error between the video image and the predetermined image, and the circuit board can be tested by matching the characteristics of the video image and the predetermined image Test, improve the flexibility of the test.

Description of drawings

Fig. 1 is the schematic flow chart of the testing method of the circuit board of the embodiment of the present invention;

Fig. 2 is the structural representation of the test system of the circuit board of the embodiment of the present invention;

3 is a schematic flow diagram of a circuit board testing method according to Embodiment 1 of the present invention;

4 is a schematic structural diagram of a circuit board testing system according to Embodiment 1 of the present invention;

5 is a schematic flow chart of a circuit board testing method according to Embodiment 2 of the present invention;

FIG. 6 is a schematic structural diagram of a circuit board testing system according to Embodiment 2 of the present invention.

Detailed ways

In order to make the above objects, features and advantages of the present invention more comprehensible, specific implementations of the present invention will be described in detail below in conjunction with the accompanying drawings.

In the following description, specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention can be implemented in many other ways than those described here, and those skilled in the art can make similar extensions without departing from the connotation of the present invention. Accordingly, the present invention is not limited to the specific embodiments disclosed below.

As described in the background art, when using the existing test method to test the circuit board integrated with the TV chip, the test cost is high, and the test efficiency and test coverage are low. Therefore, the inventor considers whether it is possible not to use a TV signal generator to generate a predetermined TV signal to reduce the test cost, and to use the predetermined TV signal to test the output TV signal of the circuit board under test, and then realize the automatic test. Improve test efficiency and test coverage.

Please refer to FIG. 1 , a schematic flow chart of a test method for a circuit board according to an embodiment of the present invention. In this embodiment, the circuit board is suitable for demodulating a received TV signal to obtain an audio output signal and a video output signal. ; The testing method of described circuit board comprises:

Step S11: sending a predetermined TV signal to the circuit board, the predetermined TV signal is modulated by a predetermined image signal and a predetermined audio signal;

Step S12: Using the predetermined audio signal to test the audio output signal output by the circuit board;

Step S13: Using the predetermined image signal to test the video output signal output by the circuit board.

In this embodiment, the predetermined image signal has known parameter information, such as the pixel value, chrominance value, brightness value, etc. of a pixel point in the image; the predetermined audio signal has known parameter information, such as the frequency of the signal , energy (strength), etc. The predetermined image signal and predetermined audio signal can be generated by VCD, DVD, computer and other electronic equipment. The predetermined audio signal may be a single-tone audio signal, or a dual-tone multi-frequency signal; the predetermined image signal may be a static image signal, or a dynamic image signal. The predetermined image signal and predetermined audio signal are modulated by a television signal transmitting device, such as a television signal transmitter, to obtain a predetermined television signal and sent to the circuit board to be tested.

Corresponding to the circuit board testing method in the embodiment of the present invention, the embodiment of the present invention also provides a circuit board testing system, the circuit board is suitable for demodulating the received TV signal to obtain the audio output signal and Video output signal; please refer to the structural representation of the test system of the circuit board of the embodiment of the present invention shown in Fig. 2, the test system of the circuit board includes:

A sending unit 11, configured to send a predetermined TV signal to the circuit board 10, the predetermined TV signal being modulated by a predetermined image signal and a predetermined audio signal;

An audio testing unit 12, configured to use the predetermined audio signal to test the audio output signal output by the circuit board 10;

The video test unit 13 is configured to use the predetermined image signal to test the video output signal output by the circuit board 10 .

In this embodiment, the circuit board 10 may be set in a mobile terminal, and may also be set in an MP4, a vehicle-mounted device, a handheld device, a palmtop computer, and the like. The sending unit 11 and the circuit board 10 send and receive TV signals through an antenna, and the circuit board 10 communicates with the audio test unit 12 and the video test unit 13 in a wireless or wired manner. The sending unit 11 may include: an audio and video signal source and a TV signal sending device, the audio and video signal source may be DVD, VCD, etc., and the TV signal sending device may be a TV signal transmitter. After receiving the predetermined TV signal sent by the sending unit 11 , the circuit board 10 performs processing such as demodulation and decoding on it to output an audio output signal and a video output signal. The audio test unit 12 tests the audio output signal output by the circuit board 10 , and the video test unit 13 tests the video output signal output by the circuit board 10 . The audio testing unit 12 and the video testing unit 13 can be integrated in a computer.

In order to better illustrate the technical solution of the present invention, the circuit board testing method and testing system of the technical solution of the present invention will be described in detail below through specific examples. In the following embodiments, a mobile terminal with a TV function is taken as an example (the circuit board is disposed in the mobile terminal), and specifically, the circuit board is integrated with a TV chip and a main control chip as an example for corresponding description.

Embodiment one

Please refer to FIG. 3 , a schematic flow chart of a circuit board testing method according to Embodiment 1 of the present invention, wherein, step S121 to step S124 correspond to step S12 in FIG. 1 , and are used to test the audio processing function of the circuit board; step S131a to step S132a It corresponds to step S13 in FIG. 1 and is used to test the video processing function of the circuit board. The test of the audio processing function and the test of the video processing function can be carried out simultaneously.

First, step S111 is executed to send a predetermined TV signal to the circuit board, and the predetermined TV signal is modulated by a predetermined image signal and a predetermined audio signal; in this embodiment, the predetermined image signal can be generated by an audio and video signal source, such as a DVD and a predetermined audio signal, and sent to the circuit board under test after being modulated by a TV signal sending device, such as a TV signal transmitter. In order to reduce the complexity of the test, in this embodiment, the predetermined audio signal is a monophonic audio signal, and the predetermined image signal is a static image signal.

The circuit board to be tested receives the predetermined TV signal, and the TV chip integrated on it demodulates the predetermined TV signal, and then the main control chip performs subsequent processing to separate the audio output signal and the video output signal. The main control chip includes a baseband chip.

Step S121 is executed to transform the audio output signal output by the circuit board from the time domain to the frequency domain. In this embodiment, if the audio signal output by the circuit board to be tested is an analog audio signal, the step S121 further includes: converting the analog audio signal output by the circuit board to be tested into a digital audio signal, such as using an analog-to-digital converter (ADC, Analog-to-Digital Converter) to digitize the analog audio signal, and the audio signal converted from the time domain to the frequency domain is a digital audio signal. Digitize the analog signal so that the subsequent test automation can be realized by digital signal processing.

To transform the audio output signal from the time domain to the frequency domain, the digital audio signal can be multiplied by a window function in the time domain first, and then the windowed digital audio can be converted to The signal is transformed into the frequency domain to obtain frequency domain information, and according to the method of signal processing, the spectral sidelobe of the signal can be reduced as much as possible.

Next, step S122 is executed to obtain the energy of the effective signal and the energy of the noise signal in the audio output signal based on the frequency of the predetermined audio signal. Since the frequency of the predetermined audio signal is known, in the spectrogram of the digital audio signal, the energy of the signal within the frequency main lobe range of the predetermined audio signal is taken as the energy of the effective signal, and the energy of the predetermined audio signal is taken as The energy of the signal outside the frequency range is the energy of the noise signal.

Next, step S123 is executed to calculate the energy ratio of the effective signal and the noise signal, so as to obtain the signal-to-noise ratio of the audio output signal. The signal-to-noise ratio is obtained by dividing the energy of the effective signal by the energy of the noise signal.

Next, step S124 is executed to compare the SNR with a preset SNR threshold. Generally speaking, if the function of the circuit board to be tested is normal, the signal-to-noise ratio of the audio output signal of the circuit board should be relatively high, for example greater than a preset signal-to-noise ratio threshold. In practical applications, the preset signal-to-noise ratio threshold can be set according to the actual application requirements. The higher the requirement for audio quality, the larger the signal-to-noise ratio threshold can be set. By comparing the calculated signal-to-noise ratio with the Ratio thresholds to detect the audio processing capabilities of the board under test. In this embodiment, the signal-to-noise ratio threshold is 10 dB, and when the signal-to-noise ratio of the audio output signal output by the circuit board to be tested is greater than or equal to 10 dB, it can be considered that the audio processing function of the circuit board to be tested is normal.

Execute step S131a: determine the error parameter based on the pixel parameters of a frame of image in the video output signal output by the circuit board and the corresponding pixel parameters in the predetermined image signal; then step S132a: compare the error parameter with the preset error Threshold to detect the video processing capabilities of the board under test. Wherein, a frame of image in the video output signal can be any frame of image in the video output signal, a frame of video image is captured by the computer from the video stream (video output signal), and the pixel parameters of the frame of image are compared with the corresponding The error parameters can be obtained by comparing the pixel parameters of the predetermined image.

The pixel parameters include: at least one of the pixel value of the pixel point, the integral value of the pixel row, and the integral value of the pixel column. Correspondingly, the error parameters include: the maximum absolute error of the pixel value, the mean square error of the pixel value, At least one of the maximum absolute error of the row integral value, the mean square error of the row integral value, the maximum absolute error of the column integral value, and the mean square error of the column integral value; correspondingly, the error threshold includes: the maximum absolute error threshold of the pixel value, the pixel value At least one of a value mean square error threshold, a row integral value maximum absolute error threshold, a row integral value mean square error threshold, a column integral value maximum absolute error threshold, and a column integral value mean square error threshold.

Wherein, the maximum absolute error of the pixel value is the maximum value of the absolute error between the pixel value of a pixel of a frame of image in the video signal and the pixel value of a corresponding pixel in the predetermined image signal.

The pixel value mean square error is an average value of squares of differences between pixel values of a frame of image in the video signal and pixel values of corresponding pixel points in the predetermined image signal.

The integral value of the pixel row is the integral value of pixel values of a row of pixel points in one frame of image in the video signal.

The maximum absolute error of the row integral value is the maximum value of the absolute error between the integral value of the pixel row of one frame image in the video signal and the integral value of the corresponding pixel row in the predetermined image signal.

The mean square error of the line integral value is the average value of the square of the difference between the line integral value of the pixel line of a frame image in the video signal and the integral value of the corresponding pixel line in the predetermined image signal.

The integral value of the pixel column is the integral value of the pixel values of a column of pixel points in one frame of image in the video signal.

The maximum absolute error of the column integral value is the maximum value of the absolute error between the integral value of the pixel column of one frame image in the video signal and the integral value of the corresponding pixel column in the predetermined image signal.

The mean square error of the column integral value is an average value of squares of differences between the column integral value of a pixel column of a frame image in the video signal and the integral value of a corresponding pixel column in the predetermined image signal.

Specifically, if the pixel parameter includes a pixel value of a pixel point, the error parameter includes at least one of a maximum absolute error of a pixel value and a mean square error of a pixel value. For example, the pixel values of each pixel in a frame of image in the video output signal are respectively: p ₁ , p ₂ , p ₃ , ..., p _n , and the pixel values of corresponding pixel points in the predetermined image are respectively: p ₁₀ , p ₂₀ , p ₃₀ ,..., p _n0 , n is the total number of pixels in a frame of image, then when the absolute error of all pixels: |p ₁ –p ₁₀ |, |p ₂ –p ₂₀ |, |p ₃ –p ₃₀ |, ..., |p _n –p _n0 | is smaller than the pixel value maximum absolute error threshold T1; or, when the pixel value mean square error: [(p ₁ –p ₁₀ ) ² + When (p ₂ –p ₂₀ ) ² +(p ₃ –p ₃₀ ) ² +…+(p _n –p _n0 ) ² ]/n is less than the pixel value mean square error threshold T2, the video processing of the circuit board under test can be determined functioning normally. Alternatively, when the maximum absolute error of the pixel value is less than the maximum absolute error threshold T1 and the mean square error of the pixel value is less than the mean square error threshold T2, it is determined that the video processing function of the circuit board under test is normal. Wherein, the pixel value maximum absolute error threshold and pixel value mean square error threshold are determined by actual application and detection requirements, for example, the value range of T1 may be 5-30, and the value range of T2 may be 10-100.

If the pixel parameter includes the integral value of the pixel row, the error parameter includes at least one of the maximum absolute error of the row integral value and the mean square error of the row integral value. For example, the integral values of pixels in each row of a frame of image in the video output signal are: I ₁ , I ₂ , I ₃ , ..., I _j , and the integral values of corresponding pixel rows in the predetermined image are: I ₁₀ , I ₂₀ , I ₃₀ ,..., I _j0 , j is the number of lines of a frame of image, then when the absolute error of all pixel lines: |I ₁ –I ₁₀ |, |I ₂ –I ₂₀ |, |I ₃ –I ₃₀ |, ..., |I _j –I _j0 | is smaller than the maximum absolute error threshold T3 of the row integral value; or, when the row integral value mean square error: [(I ₁ –I ₁₀ ) ² +(I ₂ –I When ₂₀ ) ² +(I ₃ -I ₃₀ ) ² +...+(I _j -I _j0 ) ² ]/j is less than the line integral value mean square error threshold T4, it can be determined that the video processing function of the circuit board under test is normal. Alternatively, when the maximum absolute error of the line integral value is less than the maximum absolute error threshold of the line integral value T3 and the mean square error of the line integral value is less than the line integral value mean square error threshold T4, it is determined that the video processing function of the circuit board to be tested is normal. Wherein, the maximum error threshold of the row integral value and the mean square error threshold of the row integral value are determined by actual application and detection requirements, for example, the value range of T3 can be 5*M~30*M, and the value range of T4 can be It is 10*M~100*M, where M is the total number of pixels in a row.

If the pixel parameter includes the integral value of the pixel column, the error parameter includes at least one of the maximum absolute error of the column integral value and the mean square error of the column integral value. For example, the integral values of pixels in each column of a frame of image in the video output signal are: K ₁ , K ₂ , K ₃ , ..., K _m , and the integral values of the corresponding pixel columns in the predetermined image are: K ₁₀ , K ₂₀ , K ₃₀ ,..., K _m0 , m is the number of columns of a frame of image, then when the absolute error of all pixel columns: |K ₁ –K ₁₀ |, |K ₂ –K ₂₀ |, |K ₃ –K ₃₀ |, ..., |K _m –K _m0 |The maximum value is less than the maximum absolute error threshold T5 of the column integral value; or, when the mean square error of the column integral value: [(K ₁ –I ₁₀ ) ² +(K ₂ When –K ₂₀ ) ² +(K ₃ –K ₃₀ ) ² +…+(K _m –K _m0 ) ² ]/m is less than the column integral value mean square error threshold T6, it can be determined that the video processing function of the circuit board under test is normal . Alternatively, when the maximum absolute error of the column integral value is less than the maximum absolute error threshold of the column integral value T5 and the mean square error of the column integral value is less than the threshold T6 of the column integral value mean square error, it is determined that the video processing function of the circuit board to be tested is normal. Wherein, the maximum absolute error threshold of the column integral value and the mean square error threshold of the column integral value are determined by actual application and detection requirements, for example, the value range of T5 can be 5*J~30*J, and the value range of T6 It can be 10*J~100*J, where J is the total number of pixels in a column.

Test the audio output signal output by the circuit board to be tested through steps S121-S124, and test the video output signal output by the circuit board to be tested in steps S131a-S132a, which can test whether the TV chip and the main control chip on the circuit board to be tested are invalid. 1. Whether there is any false welding in the welding of the main control chip, whether there is a problem in the connection between the TV chip and the main control chip, that is, the test of the circuit board integrated with the TV chip is realized.

Corresponding to the above-mentioned circuit board testing method, the structure of the circuit board testing system in this embodiment is shown in FIG. 4 , including: a sending unit 11 , an audio testing unit 12 , and a video testing unit 13 . The sending unit 11 , the audio testing unit 12 and the video testing unit 13 are all connected to the circuit board 10 .

Wherein, the sending unit 11 includes:

Audio and video signal source 110, used to generate a predetermined image signal and a predetermined audio signal;

The television signal sending device 111 is connected to the audio and video signal source 110 and used for modulating the predetermined image signal and predetermined audio signal to obtain a predetermined television signal and sending it to the circuit board 10 .

In this embodiment, the audio and video signal source 110 may be DVD, VCD, etc., and the TV signal sending device 111 may be a TV signal transmitter.

Described audio test unit 12 comprises:

A conversion unit 121, configured to convert the audio output signal from the time domain to the frequency domain;

An acquisition unit 122, connected to the conversion unit 121, configured to acquire the energy of the effective signal and the energy of the noise signal in the audio output signal based on the frequency of the predetermined audio signal;

a calculation unit 123, configured to calculate the energy ratio of the effective signal and the noise signal acquired by the acquisition unit 122, so as to obtain the signal-to-noise ratio of the audio output signal;

The first comparison unit 124 is configured to compare the signal-to-noise ratio calculated by the calculation unit 123 with a preset signal-to-noise ratio threshold.

In this embodiment, if the audio signal output by the circuit board is an analog audio signal, the audio test unit 12 further includes: an analog-to-digital conversion unit (not shown in the figure), which is used to digitize the analog audio signal to obtain A digital audio signal; the conversion unit is used to transform the digital audio signal from the time domain to the frequency domain. The conversion unit transforms the digital audio signal into a frequency domain using FFT.

In this embodiment, the video testing unit 13 uses the pixel parameters of the predetermined image signal to test the video output signal output by the circuit board. Specifically, the video test unit 13 includes:

An error determination unit 131a, configured to determine an error parameter based on a pixel parameter of a frame of image in the video output signal and a corresponding pixel parameter in the predetermined image signal;

The second comparison unit 132a is configured to compare the error parameter with a preset error threshold.

Optionally, the pixel parameter includes: a pixel value of a pixel point; the error parameter includes: a maximum absolute error of a pixel value; the error threshold includes: a maximum absolute error threshold of a pixel value; the maximum absolute error of a pixel value is The maximum value of the absolute error between the pixel value of a pixel point of a frame of image in the video signal and the pixel value of a corresponding pixel point in the predetermined image signal.

Optionally, the pixel parameter includes: pixel value of the pixel point; the error parameter includes: pixel value mean square error; the error threshold includes: pixel value mean square error threshold; the pixel value mean square is determined by the error The average value of the square of the difference between the pixel value of a frame of image in the video signal and the pixel value of the corresponding pixel in the predetermined image signal.

Optionally, the pixel parameters include: the integral value of the pixel row; the error parameters include: the maximum absolute error of the row integral value; the error threshold includes: the maximum absolute error threshold of the row integral value; the integral value of the pixel row is the integral value of the pixel value of a row of pixels in one frame of image in the video signal; the maximum absolute error of the row integral value is the integral value of the pixel row in one frame of image in the video signal and the predetermined image signal The maximum value of the absolute error of the integral value of the corresponding pixel row.

Optionally, the pixel parameters include: the integral value of the pixel row; the error parameter includes: the mean square error of the row integral value; the error threshold includes: the mean square error threshold of the row integral value; the integral value of the pixel row is the integral value of the pixel value of a row of pixels in a frame of image in the video signal; the mean square error of the row integral value is the integral value of the pixel row in a frame of image in the video signal and The average of the squares of the differences of the integral values of the corresponding pixel rows.

Optionally, the pixel parameters include: the integral value of the pixel column; the error parameter includes: the maximum absolute error of the column integral value; the error threshold includes: the maximum absolute error threshold of the column integral value; the integral value of the pixel column is the integral value of the pixel value of a column of pixel points of a frame image in the video signal; the maximum absolute error of the column integral value is the integral value of the pixel column of a frame image in the video signal and the predetermined image signal The maximum value of the absolute error of the integral value of the corresponding pixel column.

Optionally, the pixel parameters include: the integral value of the pixel column; the error parameter includes: the mean square error of the column integral value; the error threshold includes: the mean square error threshold of the column integral value; the integral value of the pixel column is the integral value of the pixel value of a column of pixel points of a frame image in the video signal; the mean square error of the column integral value is the integral value of the pixel column of a frame image in the video signal and the predetermined image signal The average of the squares of the differences of the integral values of the corresponding pixel columns.

The working process of the circuit board testing system of this embodiment will be briefly described below with reference to FIG. 4 . In this embodiment, the audio and video signal source 110 of the sending unit 11 generates a predetermined image signal and a predetermined audio signal, and the television signal sending device 111 transmits the predetermined television signal obtained by modulating the predetermined image signal and the predetermined audio signal to the circuit board 10 . After the circuit board 10 to be tested receives a predetermined TV signal, it performs corresponding processing to obtain an audio output signal and a video output signal. The audio test unit 12 obtains the signal-to-noise ratio of the audio output signal based on the frequency of the predetermined audio signal, and judges whether the signal-to-noise ratio is greater than a preset signal-to-noise ratio threshold, and if the signal-to-noise ratio is greater than the signal-to-noise ratio threshold, then the The audio signal processing test of the circuit board passed. The video test unit 13 captures a frame of video image in the video output signal output by the circuit board, determines the error parameter based on the pixel parameter of the video image and the corresponding pixel parameter of the predetermined image, and judges whether the error parameter is less than a preset error threshold , if the error parameter is smaller than the error threshold, the video signal processing test of the circuit board to be tested passes.

Embodiment two

In this embodiment, the test of the audio output signal output by the circuit board is the same as that in the first embodiment, but the test of the video output signal output by the circuit board is different from the first embodiment. In this embodiment, using the predetermined image signal to test the video output signal output by the circuit board includes using the characteristic parameter of the predetermined image signal to test the video output signal output by the circuit board. In addition, it should be noted that in other embodiments, the first and second embodiments can also be combined, and the video output signal is tested by using the pixel parameters and characteristic parameters of the predetermined image signal, so as to test the video processing function of the circuit board.

Please refer to the schematic flow chart of the circuit board testing method according to the second embodiment of the present invention shown in FIG. 5, the circuit board testing method includes:

Step S111: sending a predetermined TV signal to the circuit board, the predetermined TV signal is modulated by a predetermined image signal and a predetermined audio signal;

Step S121: transforming the audio output signal output by the circuit board from the time domain to the frequency domain;

Step S122: Obtain the energy of the effective signal and the energy of the noise signal in the audio output signal based on the frequency of the predetermined audio signal;

Step S123: Calculate the energy ratio of the effective signal and the noise signal to obtain the signal-to-noise ratio of the audio output signal;

Step S124: comparing the SNR with a preset SNR threshold;

Step S131b: Using an image recognition algorithm to identify the text and/or graphics of a frame of image in the video output signal;

Step S132b: matching the recognized text and/or graphics with the corresponding text and/or graphics in the predetermined image signal.

In this embodiment, step S121 to step S124 correspond to step S12 shown in FIG. 1 , and step S131b to step S132b correspond to step S13 shown in FIG. 1 . Step S131b to step S132b will be described in detail below.

Step S131b is executed, using an image recognition algorithm to identify text and/or graphics of a frame of image in the video output signal. For the text in a frame of images, before the text is recognized, it is first necessary to extract the text area, specifically to perform text detection and text segmentation. In this embodiment, an existing edge-based detection algorithm, Texture-based detection algorithms, region-based detection algorithms, etc. are used to detect text, and the existing threshold method, statistical model-based method, unsupervised clustering method, etc. are used to segment the detected text, and then optical characters are used. Recognition (OCR, Optical Character Recognition) technology recognizes the text in the extracted text area.

For the graphics in a frame of image, the existing template matching algorithm, Bayesian classification algorithm, graphics detection algorithm based on Huffman transform, etc. can be used to identify the graphics in the image.

In actual implementation, it is possible to recognize text in a frame of images, or recognize graphics in a frame of images, or recognize both text in a frame of images and graphics in a frame of images.

Execute step S132b, matching the recognized text and/or graphics with the corresponding text and/or graphics in the predetermined image signal, that is, judging that the recognized text and/or graphics and the corresponding text and/or graphics in the predetermined image Does the graph match. Specifically, the existing technology, such as grayscale matching, feature matching, etc., can be used to match the text and graphics identified in step S131b with the corresponding text and graphics in the predetermined image signal, so as to determine the Whether the text and graphics of a frame of image match the text and graphics of the corresponding frame of image in the predetermined image signal. If they match (match), the video processing function of the circuit board under test is normal.

Correspondingly, the structure of the circuit board testing system of this embodiment is shown in FIG. 6 , including: a sending unit 11 , an audio testing unit 12 , and a video testing unit 13 ′. The sending unit 11 , the audio testing unit 12 , and the video testing unit 13 ′ are all connected to the circuit board 10 .

Wherein, the sending unit 11 and the audio testing unit 12 are similar to those in the first embodiment, and for details, please refer to the description in the first embodiment, which will not be repeated here.

In this embodiment, the video test unit 13' uses the characteristic parameters of the predetermined image signal to test the video output signal output by the circuit board. The video test unit 13' includes: a recognition unit 131b, configured to use an image recognition algorithm to recognize the text and/or graphics of a frame of image in the video output signal; a matching unit 132b, used to match the recognized text and/or The graphics correspond to text and/or graphics in the predetermined image signal.

The working process of the circuit board testing system of this embodiment will be briefly described below with reference to FIG. 6 . In this embodiment, the audio and video signal source 110 of the sending unit 11 generates a predetermined image signal and a predetermined audio signal, and the television signal sending device 111 transmits the predetermined television signal obtained by modulating the predetermined image signal and the predetermined audio signal to the circuit board 10 . After the circuit board 10 to be tested receives a predetermined TV signal, it performs corresponding processing to obtain an audio output signal and a video output signal. The audio test unit 12 obtains the signal-to-noise ratio of the audio output signal based on the frequency of the predetermined audio signal, and judges whether the signal-to-noise ratio is greater than a preset signal-to-noise ratio threshold, and if the signal-to-noise ratio is greater than the signal-to-noise ratio threshold, then the The audio processing test of the board passed. The video test unit 13' captures a frame of video image in the video output signal output by the circuit board, matches the text in the video image with the specific text in the predetermined image, and matches the graphics in the video image with the specific text in the predetermined image. Graphics matching, that is, judging whether the video image contains specific text or graphics in the predetermined image, and if so, the video processing test of the circuit board to be tested has passed.

To sum up, the circuit board testing method and testing system provided by the embodiments of the present invention realize the automated testing of the circuit board, improve the test efficiency and test coverage of the circuit board test and have high flexibility, and reduce the test cost. At the same time, it also reduces the difficulty of implementing the test system of the circuit board.

Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention, and any person skilled in the art can use the methods disclosed above and technical content to analyze the present invention without departing from the spirit and scope of the present invention. Possible changes and modifications are made in the technical solution. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention, which do not depart from the content of the technical solution of the present invention, all belong to the technical solution of the present invention. protected range.

Claims (26)

1. A method for testing a circuit board, characterized in that, the circuit board comprises a TV chip, the TV chip can realize the demodulation of the TV signal, and the circuit board is suitable for demodulating the TV signal received processing, to obtain audio output signals and video output signals; the test method can test the function or performance of the circuit board, and the test of the function or performance of the circuit board includes: detecting the TV chip when receiving TV signal strength, solution Whether it is normal to adjust the function of the telecommunication signal, the test method includes: Sending a predetermined television signal, the predetermined television signal is modulated by a predetermined image signal and a predetermined audio signal, the predetermined image signal is a static image signal, and the predetermined audio signal is a monophonic audio signal; The predetermined TV signal is received by a circuit board, and the circuit board demodulates the received TV signal; After the circuit board demodulates the received TV signal, it outputs an audio output signal and a video output signal; Using the predetermined audio signal to test the audio output signal output by the circuit board; The video output signal output by the circuit board is tested by using the predetermined image signal. 2. The testing method of circuit board as claimed in claim 1, is characterized in that, described utilizing described predetermined audio signal to test the audio output signal that described circuit board outputs comprises: transforming the audio output signal from the time domain to the frequency domain; acquiring the energy of a valid signal and the energy of a noise signal in the audio output signal based on the frequency of the predetermined audio signal; calculating the energy ratio of the effective signal and the noise signal to obtain the signal-to-noise ratio of the audio output signal; Comparing the SNR with a preset SNR threshold. 3. The testing method of circuit board as claimed in claim 2, is characterized in that, the audio output signal of described circuit board output is an analog audio signal, and described utilizing described predetermined audio signal to the audio output of described circuit board output Signal testing further includes digitizing the analog audio signal prior to transforming the audio output signal from the time domain to the frequency domain. 4. The method for testing a circuit board according to claim 1, wherein said testing the video output signal output by said circuit board using said predetermined image signal comprises: utilizing pixel parameters of said predetermined image signal The video output signal is tested. 5. The testing method of circuit board as claimed in claim 4, is characterized in that, described utilizing the pixel parameter of described predetermined image signal to test described video output signal comprises: determining an error parameter based on a pixel parameter of a frame of image in the video output signal and a corresponding pixel parameter in the predetermined image signal; The error parameter is compared with a preset error threshold. 6. The testing method of circuit board as claimed in claim 5, is characterized in that, described pixel parameter comprises: the pixel value of pixel point; Described error parameter comprises: pixel value maximum absolute error; Described error threshold comprises: pixel Value Maximum Absolute Error Threshold; The maximum absolute error of the pixel value is the maximum value of the absolute error between the pixel value of a pixel of a frame of image in the video signal and the pixel value of a corresponding pixel in the predetermined image signal. 7. The testing method of circuit board as claimed in claim 5, is characterized in that, described pixel parameter comprises: the pixel value of pixel point; Described error parameter comprises: pixel value mean square error; Described error threshold comprises: pixel value Value Mean Squared Error Threshold; The pixel value mean square error is an average value of squares of differences between pixel values of a frame of image in the video signal and pixel values of corresponding pixel points in the predetermined image signal. 8. The testing method of circuit board as claimed in claim 5, is characterized in that, described pixel parameter comprises: the integral value of pixel line; Described error parameter comprises: line integral value maximum absolute error; Described error threshold comprises: The maximum absolute error threshold of the row integral value; The integral value of the pixel row is the integral value of the pixel value of a row of pixel points in a frame of image in the video signal; The maximum absolute error of the row integral value is the maximum value of the absolute error between the integral value of the pixel row of one frame image in the video signal and the integral value of the corresponding pixel row in the predetermined image signal. 9. The testing method of circuit board as claimed in claim 5, is characterized in that, described pixel parameter comprises: the integral value of pixel line; Described error parameter comprises: row integral value mean square error; Described error threshold comprises: Row integral value mean square error threshold; The integral value of the pixel row is the integral value of the pixel value of a row of pixel points in a frame of image in the video signal; The mean square error of the row integral value is the average value of the square of the difference between the integral value of the pixel row of a frame of image in the video signal and the integral value of the corresponding pixel row in the predetermined image signal. 10. The testing method of circuit board as claimed in claim 5, is characterized in that, described pixel parameter comprises: the integral value of pixel column; Described error parameter comprises: column integral value maximum absolute error; Described error threshold comprises: Column integral value maximum absolute error threshold; The integral value of the pixel column is the integral value of the pixel value of a column of pixel points of a frame image in the video signal; The maximum absolute error of the column integral value is the maximum value of the absolute error between the integral value of the pixel column of one frame image in the video signal and the integral value of the corresponding pixel column in the predetermined image signal. 11. The testing method of circuit board as claimed in claim 5, is characterized in that, described pixel parameter comprises: the integral value of pixel column; Described error parameter comprises: column integral value mean square error; Described error threshold comprises: Column integral value mean square error threshold; The integral value of the pixel column is the integral value of the pixel value of a column of pixel points of a frame image in the video signal; The mean square error of the column integral value is an average value of the square of the difference between the integral value of the pixel column of one frame image in the video signal and the integral value of the corresponding pixel column in the predetermined image signal. 12. The method for testing a circuit board according to claim 1, wherein the testing of the video output signal output by the circuit board using the predetermined image signal comprises: using the characteristic parameters of the predetermined image signal The video output signal is tested. 13. The testing method of circuit board as claimed in claim 12, is characterized in that, described utilizing the feature parameter of described predetermined image signal to test described video output signal comprises: Using an image recognition algorithm to recognize the text and/or graphics of a frame of image in the video output signal; matching the recognized text and/or graphics with the corresponding text and/or graphics in the predetermined image signal. 14. A test system for a circuit board, characterized in that the circuit board includes a TV chip, the TV chip can demodulate TV signals, and the circuit board is suitable for demodulating received TV signals processing to obtain audio output signals and video output signals; the test system can test the function or performance of the circuit board, and the test of the function or performance of the circuit board includes: detecting the TV chip when receiving TV signal strength, solving Whether it is normal to adjust the function of the telecommunication signal, the test system includes: a sending unit, configured to send a predetermined television signal, the predetermined television signal being modulated by a predetermined image signal and a predetermined audio signal; The predetermined TV signal is received by a circuit board, and the circuit board demodulates the received TV signal; After the circuit board demodulates the received TV signal, it outputs an audio output signal and a video output signal; an audio test unit, configured to use the predetermined audio signal to test the audio output signal output by the circuit board; A video test unit, configured to use the predetermined image signal to test the video output signal output by the circuit board. 15. The testing system of circuit board as claimed in claim 14, is characterized in that, described audio frequency testing unit comprises: a conversion unit, configured to transform the audio output signal from the time domain to the frequency domain; an acquisition unit, configured to acquire the energy of an effective signal and the energy of a noise signal in the audio output signal based on the frequency of the predetermined audio signal; a calculation unit, configured to calculate the energy ratio of the effective signal and the noise signal, so as to obtain the signal-to-noise ratio of the audio output signal; A first comparing unit, configured to compare the signal-to-noise ratio with a preset signal-to-noise ratio threshold. 16. The testing system of circuit board as claimed in claim 15, is characterized in that, the audio output signal of described circuit board output is analog audio signal, and described audio frequency test unit also comprises: an analog-to-digital conversion unit for digitizing the analog audio signal to obtain a digital audio signal; The converting unit is configured to convert the digital audio signal from the time domain to the frequency domain. 17. The circuit board testing system according to claim 14, wherein the video testing unit uses pixel parameters of the predetermined image signal to test the video output signal. 18. The testing system of circuit board as claimed in claim 17, is characterized in that, described video testing unit comprises: An error determination unit, configured to determine an error parameter based on a pixel parameter of a frame of image in the video output signal and a corresponding pixel parameter in the predetermined image signal; The second comparison unit is used to compare the error parameter with a preset error threshold. 19. The test system of circuit board as claimed in claim 18, it is characterized in that, described pixel parameter comprises: the pixel value of pixel point; Described error parameter comprises: pixel value maximum absolute error; Described error threshold comprises: pixel Value Maximum Absolute Error Threshold; The maximum absolute error of the pixel value is the maximum value of the absolute error between the pixel value of a pixel of a frame of image in the video signal and the pixel value of a corresponding pixel in the predetermined image signal. 20. The test system of circuit board as claimed in claim 18, is characterized in that, described pixel parameter comprises: the pixel value of pixel point; Described error parameter comprises: pixel value mean square error; Described error threshold comprises: pixel value Value Mean Squared Error Threshold; The pixel value mean square error is an average value of squares of differences between pixel values of a frame of image in the video signal and pixel values of corresponding pixel points in the predetermined image signal. 21. The test system of circuit board as claimed in claim 18, it is characterized in that, described pixel parameter comprises: the integral value of pixel line; Described error parameter comprises: line integral value maximum absolute error; Described error threshold comprises: The maximum absolute error threshold of the row integral value; The integral value of the pixel row is the integral value of the pixel value of a row of pixel points in a frame of image in the video signal; The maximum absolute error of the row integral value is the maximum value of the absolute error between the integral value of the pixel row of one frame image in the video signal and the integral value of the corresponding pixel row in the predetermined image signal. 22. The test system of circuit board as claimed in claim 18, it is characterized in that, described pixel parameter comprises: the integral value of pixel line; Described error parameter comprises: line integral value mean square error; Described error threshold comprises: Row integral value mean square error threshold; The integral value of the pixel row is the integral value of the pixel value of a row of pixel points in a frame of image in the video signal; The mean square error of the row integral value is the average value of the square of the difference between the integral value of the pixel row of a frame of image in the video signal and the integral value of the corresponding pixel row in the predetermined image signal. 23. The testing system of circuit board as claimed in claim 18, is characterized in that, described pixel parameter comprises: the integral value of pixel column; Described error parameter comprises: column integral value maximum absolute error; Described error threshold comprises: Column integral value maximum absolute error threshold; The integral value of the pixel column is the integral value of the pixel value of a column of pixel points of a frame image in the video signal; The maximum absolute error of the column integral value is the maximum value of the absolute error between the integral value of the pixel column of one frame image in the video signal and the integral value of the corresponding pixel column in the predetermined image signal. 24. The test system of circuit board as claimed in claim 18, it is characterized in that, described pixel parameter comprises: the integral value of pixel column; Described error parameter comprises: column integral value mean square error; Described error threshold comprises: Column integral value mean square error threshold; The integral value of the pixel column is the integral value of the pixel value of a column of pixel points of a frame image in the video signal; The mean square error of the column integral value is an average value of the square of the difference between the integral value of the pixel column of one frame image in the video signal and the integral value of the corresponding pixel column in the predetermined image signal. 25. The circuit board testing system according to claim 14, wherein the video testing unit uses the characteristic parameters of the predetermined image signal to test the video output signal. 26. The testing system of circuit board as claimed in claim 25, is characterized in that, described video testing unit comprises: A recognition unit, configured to use an image recognition algorithm to recognize text and/or graphics of a frame of image in the video output signal; A matching unit, configured to match the recognized text and/or graphics with corresponding text and/or graphics in the predetermined image signal.